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Pyrrosia annamensis comb. nov (Polypodiaceae) from Southeast Asia and lectotypification of Cyclophorus rhomboidalis
No full textA new combination, Pyrrosia annamensis (Christ) Li Bing Zhang, X. M. Zhou & C.W. Chen, for a Southeast Asian species formerly treated in Niphobolus is made. We also lectotypify Cyclophorus rhomboidalis Bonaparte
TAXONOMIC REVISION OF THE FERN GENUS CTENITIS (DRYOPTERIDACEAE) FROM AFRICA AND THE WESTERN INDIAN OCEAN
No full textA taxonomic revision of Ctenitis (C. Chr.) C. Chr. (Dryopteridaceae) from Africa and the Western Indian Ocean was carried out. Forty species are recognized, of which 12 are described as new, eight are transferred to Ctenitis from other genera, and one is elevated from variety to species and transferred from Aspidium Sw. to Ctenitis. These 21 nomenclatural novelties include C. analamazaotrensis (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. brevipetiolulata Li Bing Zhang & Yi F. Duan (sp. nov.), C. bullescens Rouhan, Li Bing Zhang & Yi F. Duan (sp. nov.), C. cerea Li Bing Zhang & Yi F. Duan (sp. nov.), C. comorensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. crinigera (C. Chr.) Hennequin & Rouhan (comb. nov.), C. decaryana (C. Chr.) Hennequin & Rouhan (comb. nov.), C dentata Li Bing Zhang & Yi F. Duan (sp. nov.), C. fibrillosa (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. hispida (Kuhn) Li Bing Zhang & Yi F. Duan (comb. & stat. nov.), C. jouyana (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. longivillosa Li Bing Zhang & Yi F. Duan (sp. nov.), C. marginalisora Li Bing Zhang & Yi F. Duan (sp. nov.), C mayottensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. multilobata Li Bing Zhang, Yi F. Duan & Rouhan (sp. nov.), C. reunionensis Hennequin, Li Bing Zhang & Yi F. Duan (sp. nov.), C. sieberiana (Kaulf.) Hennequin & Rouhan (comb. nov.), C sparsa Li Bing Zhang & Yi F. Duan (sp. nov.), C. spekei (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. subcrenulata (Baker) Li Bing Zhang, Rouhan & Yi F. Duan (comb. nov.), and C tardieu-blotiae Li Bing Zhang & Yi F. Duan (sp. nov.). A key to these species is provided; all species are described and illustrated; and information on their distribution and habitats is given. Twenty-three relevant species reported in the literature are excluded from the flora, and their taxonomy, distribution, and nomenclature are discussed. Seventeen related names are lectotypified or neotypified including Aspidium cirrhosum Schumach., A. crinitum (Poir.) Wall. var. hispida Kuhn, A. cyclochlamys Fee, A. nitidum Bory ex Willd., A. pauciflorum Kaulf., A. sulcatum Kaulf. ex Bory, C. anjenabensis Tardieu, Dryopteris blepharochlamys C. Chr., Gymnogramma subsimilis Hook., Nephrodium crinitum (Poir.) Desv. var. maritimum Cordem, N.. magnum Baker, N. spekei Baker, N. welwitschii Baker, Phegopteris biformis Mett. ex Kuhn, P. bivestita Mett., Polypodium baronii Baker, and P. efulense Baker; type information of related 262 names is also given
Seasonal variations in the soil amino acid pool and flux following the conversion of a natural forest to a pine plantation on the eastern Tibetan Plateau, China
No full textAlthough the importance of amino acids to plant nitrogen (N) nutrition in most terrestrial ecosystems is being increasingly recognized, the availability and seasonal variations of soil amino acids in subalpine coniferous forests are poorly understood. Few studies have investigated the differences in the soil amino acid pool and the cycling between forest types caused by land-use changes. In this study, we quantified the concentrations and fluxes of soil amino acids in a dragon spruce plantation and an adjacent natural forest (NF) on the eastern Tibetan Plateau, China. Soil samples from organic and mineral soil horizons were collected in May, July, September, and December of 2015 and March of 2016. The pools and fluxes of soil amino acids in the plantation converted from NF decreased significantly during the growing season and increased during the non-growing season. Meanwhile, greater pools and fluxes of soil amino acids were observed in the organic horizon than in the mineral soil horizon in both forest types. Our results indicate that distinct nutrient economies were likely formed in the plantation compared with the NF because the quality of the input litter decreased in the plantation. In addition, the importance of soil amino acids in the subalpine coniferous forest ecosystem was evaluated based on published literature. The ratios of amino acids to dissolved inorganic N (DIN) in the soils from the two studied forests were generally much lower than the range of ratios reported for other ecosystems. However, the relative high amino acid: DIN ratio in the plantations during the non-growing season suggests that the plants in the plantation may have the potential to modify their strategies for acquiring N due to the changed relative dominance between the DIN and amino acids in the soils. (C) 2016 Elsevier Ltd. All rights reserved
川西亚高山针叶林云杉和冷杉生长季和非生长季叶片碳氮磷化学计量特征
No full text以川西亚高山针叶林主要优势树种粗枝云杉(Picea asperata)和岷江冷杉(Abies faxoniana)为研究对象,通过比较叶片碳(C)、氮(N)、磷(P)浓度及其化学计量比在生长季(8月)和非生长季(1月)的特征,分析其变化规律并对碳氮磷进行相关性分析.结果显示,云杉和冷杉叶片C、N、P浓度及其计量比均受到采样季节的显著影响,云杉和冷杉叶片C浓度均表现为生长季显著高于非生长季,生长季云杉N浓度显著低于非生长季,生长季云杉和冷杉P浓度均显著低于非生长季.C:N、C:P以及N:P均表现为生长季显著高于非生长季.生长季云杉和冷杉叶C:N:P质量比分别为407:13:1、447:14:1,非生长季C:N:P质量比分别为274:11:1、235:9:1.仅C浓度存在显著的树种间差异,表现为非生长季云杉叶片C浓度显著低于冷杉.两树种叶C、N、P浓度相关性分析结果表明云杉和冷杉叶片C浓度与N浓度、P浓度呈显著负相关,N浓度和P浓度呈显著正相关.本研究表明云杉和冷杉叶中C、N、P化学计量特征主要受生长季节影响,但若要全面了解川西亚高山针叶林C、N、P化学计量特征,还需长期研究并与林下土壤C、N、P化学计量比结合起来讨论分析
高山草地长花马先蒿的性状和生物量分配对坡向的适应
No full text长花马先蒿(Pedicularis longiflora)是一种传统药用植物,广泛分布在高山草地及溪流旁等处.为了更好地开发、利用和保护该药用植物,从植物性状和生物量分配着手,探讨其对环境变化的适应性,首先测定不同坡向基本环境因子,然后对比不同坡向长花马先蒿的叶片性状、叶片数目、株高及其之间的相关性和权衡关系,其次从生物量分配的角度探究该植物对不同坡向的适应对策,进而阐述该植物性状及生物量指标与环境因子的回归关系,最后从功能性状到个体生物量进行尺度上推.结果表明,长花马先蒿主要通过调整比叶面积适应不同的坡向生境,西南坡植株的比叶面积为(175.272±6.597)cm2/g,比东南坡植株大.长花马先蒿成对器官生物量之间均为等速生长关系(α=1),给定茎生物量时,西南坡植株的叶生物量相对更大,形成更有利于光合作用的适应对策,而东南坡植株更多地投入到繁殖器官,使种群得以更好延续,其生物量分配受等速生长关系的限制,同时在环境因子的影响下,存在着"最优分配".温度和群落内竞争是影响该植物性状和生物量分配的主要因素,从药用植物资源保育的角度考虑,长花马先蒿人工繁育过程需要适宜的生长温度,并减少群落内的物种竞争.因此,在环境因子的作用下长花马先蒿的性状和生物量分配存在一定的权衡和适应,这可为该药用资源的开发和利用提供支撑
pH and glutathione dual-triggered supramolecular assemblies as synergistic and controlled drug release carriers
No full textA pH and glutathione (GSH) dual bio-relevant triggered supramolecular system is constructed through the non-covalent host-guest interactions between the adamantane (ADA) on camptothecin (CPT) and beta-cyclodextrin (beta-CD) on the side chain of the backbone of hyaluronic acid (HA). The obtained non-covalent supramolecular beta-CD-g-OX-HA/ADA-CPT complex could further self-assemble into a stable uniform sphere micellar structure with constant drug loading content in the extracellular environment but is cleaved in the cytosol of the cancer cells due to the acidic environment and the presence of a high concentration of GSH, resulting in a synergistic-fast pH and GSH triggered drug releasing behavior. The cytotoxicity of the supramolecular beta-CD-g-OX-HA/ADA-CPT micelles was investigated using Hep G2 cancer cells by MTT assays, which displayed that supramolecular beta-CD-g-OX-HA/ADA-CPT micelles had exhibited enhanced cellular proliferation inhibition against Hep G2 cancer cells compared to the free CPT, while the beta-CD-g-OX-HA had good cell compatibility. In vivo studies of the beta-CD-g-OX-HA/ADA-CPT micelles showed a higher in vivo efficacy without side effects and also confirmed the compatibility of the beta-CD-g-OX-HA. It is anticipated that this supramolecular complex will give the possibility to fabricate new types of bio-relevant triggered nanocarriers for cancer therapy
Loss of Tmem30a leads to photoreceptor degeneration
No full textPhosphatidylserine (PS) is asymmetrically distributed between the outer and inner leaflets of the plasma membrane in eukaryotic cells. PS asymmetry on the plasma membrane depends on the activities of P4-ATPases, and disruption of PS distribution can lead to various disease conditions. Folding and transporting of P4-ATPases to their cellular destination requires the beta subunit TMEM30A proteins. However, the in vivo functions of Tmem30a remain unknown. To this end, we generated retinal-specific Tmem30a-knockout mice to investigate its roles in vivo for the first time. Our data demonstrated that loss of Tmem30a in mouse cone cells leads to mislocalization of cone opsin, loss of photopic electroretinogram (ERG) responses and loss of cone cells. Mechanistically, Tmem30a-mutant mouse embryonic fibroblasts (MEFs) exhibited diminished PS flippase activity and increased exposure of PS on the cell surface. The broad loss of Tmem30a in adult mice led to a reduced scotopic photoresponse, mislocalization of ATP8A2 to the inner segment and cell body, and increased apoptosis in the retina. Our data demonstrated novel essential roles of Tmem30a in the retina
Flavonoid glycosides isolated from Epimedium brevicornum and their estrogen biosynthesis-promoting effects
No full textEpimedium brevicornum Maxim has a long history of use in the treatment of estrogen deficiency-related diseases. However, the chemical constituents and mechanism of action of this medicinal plant are not fully understood. In the present study, we isolated four new isoprenylated flavonoid glycosides, as well as 16 known flavonoids (13 isoprenylated flavonoids), from this plant. The chemical structures of the new flavonoid glycosides were elucidated by extensive spectroscopic analysis. The new compounds 1-4 were potent promoters of estrogen biosynthesis in human ovarian granulosa-like KGN cells. ZW1, an isoprenylated flavonoid analogue and a specific inhibitor of phosphodiesterase 5 (PDE5), was synthesized and used to explore the mechanism of the isoprenylated analogues on estrogen biosynthesis. ZW1 treatment increased estrogen production by upregulation of aromatase mRNA and protein expression. ZW1 increased the phosphorylation of cAMP response element-binding protein (CREB). Further study showed that the inhibition of PDE5 by ZW1 increased estrogen biosynthesis partly through suppression of phosphodiesterase 3 (PDE3). Our results suggested that the isoprenylated flavonoids from E. brevicornum may produce beneficial health effects through the promotion of estrogen biosynthesis. PDE5 warrants further investigation as a new therapeutic target for estrogen biosynthesis in the prevention and treatment of estrogen-deficiency related diseases
Pharmaceutical Intermediate-Modified Gold Nanoparticles: Against Multidrug-Resistant Bacteria and Wound-Healing Application via an Electrospun Scaffold
No full textRemedying a multidrug-resistant (MDR) bacteria wound infection is a major challenge due to the inability of conventional antibiotics to treat such infections against MDR bacteria. Thus, developing wound dressings for wound care, particularly against MDR bacteria, is in huge demand. Here, we present a strategy in designing wound dressings: we use a small molecule (6-aminopenicillanic acid, APA)-coated gold nanoparticles (AuNPs) to inhibit MDR bacteria. We dope the AuNPs into electrospun fibers of poly(epsilon-caprolactone) (PCL)/gelatin to yield materials that guard against wound infection by MDR bacteria. We systematically evaluate the bactericidal activity of the AuNPs and wound-healing capability via the electrospun scaffold. APA-modified AuNPs (Au_APA) exhibit remarkable antibacterial activity even when confronted with MDR bacteria. Meanwhile, Au_APA has outstanding biocompatibility. Moreover, an in vivo bacteria-infected wound-healing experiment indicates that it has a striking ability to remedy a MDR bacteria wound infection. This wound scaffold can assist the wound care for bacterial infections
Chemical Constituents of the Aerial Parts of Schnabelia oligophylla
No full textA new triterpenoid derivative, 2,3-seco-bauer-8-en-2,3-dioic acid (1), a new natural product, 3 alpha-hydroxyolean-13(18)-en-24-oic acid (2), along with 19 known compounds (3-21), were isolated from the methanol extract of the aerial parts of Schnabelia oligophylla. The chemical structures were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy and comparison with previously reported data