Relevant bibliographies by topics / Huperzine

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Academic literature on the topic 'Huperzine'

Author: Grafiati
Published: 4 June 2021
Last updated: 11 February 2022

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Journal articles on the topic "Huperzine"

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Xu, Maonian, Starri Heidmarsson, Margret Thorsteinsdottir, Pawel Wasowicz, Hang Sun, Tao Deng, Sesselja Omarsdottir, and Elin Olafsdottir. "Infraspecific Variation of Huperzine A and B in Icelandic Huperzia selago Complex." Planta Medica 85, no. 02 (October 5, 2018): 160–68. http://dx.doi.org/10.1055/a-0752-0295.

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AbstractThe alkaloids huperzine A and huperzine B were originally isolated from the Chinese club moss Huperzia serrata. They are known inhibitors of acetylcholinesterase, and especially huperzine A shows pharmaceutical potential for the treatment of Alzheimerʼs disease. Its supply heavily relies on natural plant sources belonging to the genus Huperzia, which shows considerable interspecific huperzine A variations. Furthermore, taxonomic controversy remains in this genus, particularly in the Huperzia selago group. With focus on Icelandic H. selago taxa, we aimed to explore the relatedness of Huperzia species using multi-locus phylogenetic analysis, and to investigate correlations between huperzine A contents, morphotypes, and genotypes. Phylogenetic analysis was performed with five chloroplastic loci (the intergenic spacer between the photosystem II protein D1 gene and the tRNA-His gene, maturase K, ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit, tRNA-Leu, and the intergenic spacer region between tRNA-Leu and tRNA-Phe). Huperzine A and huperzine B contents were determined using an HPLC-UV method. The phylogenetic analysis suggests that previously proposed Huperzia appressa and Huperzia arctica should not be considered species, but rather subspecies of H. selago. Three genotypes of Icelandic H. selago were identified and presented in a haplotype networking diagram. A significantly (p < 0.05) higher amount of huperzine A was found in H. selago genotype 3 (264 – 679 µg/g) than genotype 1 (20 – 180 µg/g), where the former shows a typical green and reflexed “selago” morphotype. The huperzine A content in genotype 3 is comparable to Chinese H. serrata and a good alternative huperzine A source. Genotype 2 contains multiple morphotypes with a broad huperzine A content (113 – 599 µg/g). The content of huperzine B in Icelandic taxa (6 – 13 µg/g) is much lower than that in Chinese H. serrata (79 – 207 µg/g).
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Ngọc, Vũ Thị, Phạm Thị Hạnh, Lê Thị Lan Anh, Nguyễn Tiến Đạt, and Lê Thị Bích Thủy. "Qualification and quantification of huperzine a from Huperia serrata in Da Lat, Lam Dong province." Vietnam Journal of Biotechnology 14, no. 3 (September 30, 2016): 473–78. http://dx.doi.org/10.15625/1811-4989/14/3/9861.

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Huperzine A, an alkaloid, was originally isolated from Huperzia serrata. This compound potentially enhances the memory in animal, hence, it has been approved as a drug for the clinical treatment of Alzheimer’s disease, a major disease affecting the elderly population throughout the world. Because Huperzine A is an acetylcholinesterase inhibitor, the presentation of Huperzine A in brain inhibited acetylcholinesterase activity, thus, leading to the increase in concentration of acetylcoline. In Vietnam, H. serrata distributed in Sapa (Lao Cai) and Da Lat (Lam Dong), this species provide valuable pharmaceutical materials to the treatment for Alzheimer’s diseases. In this research, we evaluated the availability of Huperzine A in Huperzia serrata, which was collected from Da Lat (Lam Dong) in two seasons: Spring and Autunm. Thin layer chromatography (TLC) method was used to preliminary qualitative analysis. High performance liquid chromatography (HPLC) method were used for determining Huperzine A content in samples. In the result, Huperzine A is almost existed in leaves of Da Lat Huperzia serrata and equivalent levels of Chinese Huperzia serrata. The Content of Huperzine A was different between two collection samples in Spring and Autumn, by analyze HPLC data, the samples was harvested in Autumn contents 92.5 µg.g-1dry sample and the spring is 75.4 µg.g-1 dry sample. Therefore, the content of Huperzine A in Huperzia serrata’s leaves sample is harvested in the fall compared with samples collected in the spring is higher 17.1 µg.g-1dry samples.
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Patočka, Jiří. "Huperzine A - An Interesting Anticholinesterase Compound from the Chinese Herbal Medicine." Acta Medica (Hradec Kralove, Czech Republic) 41, no. 4 (1998): 155–57. http://dx.doi.org/10.14712/18059694.2019.181.

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Huperzine A, alkaloid from the Chinese herbal medicine Qian Ceng Ta, which is prepared from the moss Huperzia serrata, has been used in China for centuries to treat fever and inflammation. Huperzine A is a strong inhibitor of cholinesterases with high selectivity to acetylcholinesterase and in China is developed as therapeutic against Alzheimer's disease. May be that huperzine A will be better than other centrally active anticholinesterases in treating this neurodegenerative disorder. Huperzine A appears to have additional pharmacological properties that make it an attractive candidate therapy for clinical trials.
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Ho, Raimana, Niloufar Marsousi, Philippe Eugster, Jean-Pierre Bianchini, and Phila Raharivelomanana. "Detection by UPLC/ESI-TOF-MS of Alkaloids in Three Lycopodiaceae Species from French Polynesia and Their Anticholinesterase Activity." Natural Product Communications 4, no. 10 (October 2009): 1934578X0900401. http://dx.doi.org/10.1177/1934578x0900401007.

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Three Lycopodiaceae species from French Polynesia, Lycopodium venustulum C. Gaudichaud, Lycopodiella cernua (C. Linnaeus) R. E. Pichi Sermolli and Lycopodium henryanum E. D. Brown were investigated for their alkaloidal composition by UHPLC/ESI-TOF-MS. Ten alkaloids were identified, with lycopodine and lycodoline being the main constituents in the three species. The acetylcholinesterase-inhibitory activities of the three species are probably due to the occurrence of huperzine A, huperzine B, huperzine E, huperzinine and lycopodine.
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Nguyen, Ngoc Chuong, Dinh Vinh, Duc Tuan Nguyen, Huynh Van Thi Nguyen, Cong Luan Tran, and Manh Hung Tran. "Development of a Capillary Electrophoretic Method for the Determination of Huperzine A Concentration in Vietnamese Huperzia serrata." Natural Product Communications 16, no. 9 (September 2021): 1934578X2110332. http://dx.doi.org/10.1177/1934578x211033225.

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Huperzine A, isolated from Huperzia serrata, is a potent, specific, and reversible inhibitor of acetylcholinesterase with high efficiency and low toxicity. To evaluate the presence of huperzine A in Vietnamese H serrata, a reliable capillary zone electrophoresis method was developed. The analytical conditions were established using 80 mM ammonium acetate buffer, pH 6.0, hydrodynamic injection at 50 mbar for 5 s, applied voltage of 20 kV, temperature at 25 °C, uncoated fused-silica capillary, 56 cm (50 cm effective length) × 70 µm inner diameter, and ultraviolet detection at 310 nm. The recovery rates ranged from 98.05% to 100.64%, with a relative standard deviation <2%. Good linear regression was observed in the concentration range of 1 to 500 µg/mL, with a correlation coefficient of 0.9994. The limit of detection and limit of quantification were 0.33 and 1.0 µg/mL, respectively. These results demonstrate that this method is simple, selective, and suitable for performing quality control for huperzine A derived from Vietnamese H serrata.
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Ma, Xiaoqiang, Changheng Tan, Dayuan Zhu, David R. Gang, and Peigen Xiao. "Huperzine A from Huperzia species—An ethnopharmacolgical review." Journal of Ethnopharmacology 113, no. 1 (August 2007): 15–34. http://dx.doi.org/10.1016/j.jep.2007.05.030.

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Zhang, Yanqing, Junbo Xie, Wen-Qian Chen, Tian-Yan Zhou, and Wei Lu. "Development of a Sensitive High-Performance Liquid Chromatographic Method with Simple Extraction for Simultaneous Determination of Huperzine A and Huperzine B in the Species Containing Lycopodium Alkaloids." Journal of AOAC INTERNATIONAL 92, no. 4 (July 1, 2009): 1060–63. http://dx.doi.org/10.1093/jaoac/92.4.1060.

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Abstract A sensitive HPLC method with simple extraction was developed for simultaneous determination of huperzine A (HupA) and huperzine B (HupB) in Huperzia serrata, H. crispata, H. miyoshiana, and Lycopodiastrum casuarinoides. In order to avoid conventional multiple-step and time-consuming sample preparation methods, direct reflux extraction with alkaline chloroform was adopted. The quantitative determination was conducted by reversed-phase HPLC with a photodiode array detector set at 308 nm. Separation was performed on a Luna C18 column (250 4.6 mm id, 5 m) with methanol0.2 aqueous acetic acid (18 + 82, v/v) mobile phase. The method was validated for accuracy, reproducibility, precision, and limits of detection and quantification. Quantification of the two active compounds in the samples was performed by this newly developed method, and the content of HupA and HupB varied substantially among four different species. The satisfactory results indicated that the developed method can readily be utilized for quality control of the species of Huperziaceae and Lycopodiaceae containing the two compounds.
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Szypuła, Wojciech J., Beata Wileńska, Aleksandra Misicka, and Agnieszka Pietrosiuk. "Huperzine A and Huperzine B Production by Prothallus Cultures of Huperzia selago (L.) Bernh. ex Schrank et Mart." Molecules 25, no. 14 (July 17, 2020): 3262. http://dx.doi.org/10.3390/molecules25143262.

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This is the first report of an efficient and effective procedure to optimize the biosynthesis of huperzine A (HupA) and huperzine B (HupB) in vitro from Huperzia selago gametophytes. Axenic tissue cultures were established using spores collected from the sporophytes growing in the wild. The prothalia were obtained after 7–18 months. Approximately 90 up to 100% of the gametophytes were viable and grew rapidly after each transfer on to a fresh medium every 3 months. The best biomass growth index for prothallus calculated on a fresh (FW) and dry weight (DW) basis, at 24 weeks of culture, was 2500% (FW) and 2200% (DW), respectively. The huperzine A content in the gametophytes was very high and ranged from 0.74 mg/g to 4.73 mg/g DW. The highest yield HupA biosynthesis at >4 mg/g DW was observed on W/S medium without growth regulators at 8 to 24 weeks of culture. The highest HupB content ranged from 0.10 mg/g to 0.52 mg/g DW and was obtained on the same medium. The results demonstrate the superiority of H. selago gametophyte cultures, with the level of HupA biosynthesis approximately 42% higher compared to sporophyte cultures and 35-fold higher than when the alkaloid was isolated from H. serrata, its current source for the pharmaceutical industry. Moreover, the biosynthesis of HupB was several-fold more efficient than in H. selago sporophytes growing in the wild. HPLC-HR-MS analyses of the extracts identified eight new alkaloids previously unreported in H. selago: deacetylfawcettine, fawcettimine, 16-hydroxyhuperzine B, deacetyllycoclavine, annopodine, lycopecurine, des-N-methylfastigiatine and flabelline.
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Tan, Chang-Heng, Shan-Hao Jiang, and Da-Yuan Zhu. "Huperzine P, a novel Lycopodium alkaloid from Huperzia serrata." Tetrahedron Letters 41, no. 30 (July 2000): 5733–36. http://dx.doi.org/10.1016/s0040-4039(00)00893-5.

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&NA;. "Huperzine A." Drugs in R & D 5, no. 1 (2004): 44–45. http://dx.doi.org/10.2165/00126839-200405010-00009.

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Dissertations / Theses on the topic "Huperzine"

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Caprio, Vittorio. "A convergent approach to huperzine A." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389646.

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Lucey, Cathal Daniel. "Synthesis of Huperzine A and analogues." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485064.

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Huperzine A is a natural product, originally isolated from the Chinese club moss Huperzia serrata, which is currently undergoing clinical trials in the U.S. and has already been approved in China for the treatment of Alzheimer's disease (AD). This sesquiterpene alkaloid of the Lycopodium family is an eXGellent selective and reversible inhibitor of acetylcholinesterase (AChE), which is an established target in the palliative treatment of AD. Huperzine A has been the target of several syntheses and a number of analogues have also been prepared. However, all of the synthetic approaches to date have been essentially linear and thus not ideal for analogue preparation. This thesis describes the completed development of the first formal convergent synthesis of (±)-huperzine A, starting from commercially available cyclohex-2-enone and aminopicoline. A key step in the synthesis is an intramolecular Heck cyclisation, which gives the core tricycle of the natural product Optimisation of the intramolecular Heck reaction allowed for it to be carried out on a multi-gram scale and in 72% yield. Once completed, th~ converg~nt synthesis could now be used in the preparation ofnovel huperzine A analogues, which would be tested for AChE inhibitory activity and also for broad range CNS activity. Initial analogue work described in this thesis has proved promising, with a nitrogen atom having been successfully incorporated into the tricyclic core at two different positions via Beckmann rearrangements. This thesis also describes the resolution of a key intermedi~te in the newly-developed racemic synthesis, thus allowing for the synthesis of enantiomerically-pure huperzine A or related analogues.
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Kelly, S. A. "A convergent approach to huperzine A and analogues." Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403166.

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Foricher, Yann. "A convergent synthesis of the skeleton of huperzine A and analogues." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342106.

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Booth, Susan E. "New synthetic methods in an approach to huperzine A and B." Thesis, University of Leicester, 1992. http://hdl.handle.net/2381/34022.

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The aim of the research was to develop a flexible, stereocontrolled route to huperzine A and B and other lycopodium alkaloids. One of the main objectives was to investigate whether intramolecular radical cyclisation reactions on to carbon-nitrogen double bonds might provide a new method for the synthesis of key intermediates in the total synthesis. To this end the intramolecular cyclisation reactions of vinyl and aryl radicals on to oxime ethers have been explored and these reactions have been used to prepare a number of useful bicyclic and tricyclic carbocyclic compounds and related heterocyclic compounds in good yields. This represents essentially new synthetic methodology as prior to this work there was only one reported example of the use of an oxime ether as a radical trap. The best reagent for these reactions utilising vinyl and aryl halide precursors was found to be tributyltin hydride. Preliminary attempts to carry out tandem radical cyclisation reactions incorporating oxime ethers have not, so far, been successful on the model systems investigated. This new synthetic strategy has been used to carry out one-carbon ring expansions of five-membered cyclic oxime ethers similar to those reported recently for carbonyl compounds. However, attempts to extend this ring expansion to the two-carbon system resulted only in cyclisation to give a bicyclic compound, rather than ring expansion. Attempts to cleave the N-O bonds of some of the hydroxylamines resulting from these cyclisation reactions proved to be unsuccessful using SmI2, Zn and acetic acid or aluminium amalgam. Attempted cleavage of the N-O alkyl bond of a hydroxylamine group adjacent to an aromatic ring using lithium aluminium hydride resulted in a novel ring expansion reaction, which may occur by an unusual electron transfer process to give radical intermediates.
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SAMKAOUI, ABDESSAMAD. "Etude chimique et pharmacologique de la galanthamine et de l'huperzine a dans le traitement de la maladie d'alzheimer." Strasbourg 1, 1995. http://www.theses.fr/1995STR15005.

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Oluwafemi, A. J., O. Okanla, P. Camps, D. Muñoz-Torrero, Z. B. Mackey, P. K. Chiang, Scott Seville, and Colin W. Wright. "Evaluation of cryptolepine and huperzine derivatives as lead compounds towards new agents for the treatment of human African Trypanosomiasis." Natural Products Inc, 2009. http://hdl.handle.net/10454/4534.

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no
The alkaloid cryptolepine (1) and eight synthetic analogues (2-8) were assessed for in vitro activities against Trypanosoma brucei. Four of the analogues were found to be highly potent with IC50 values of less than 3 nM and three of these were assessed against T. brucei brucei infection in rats. The most effective compound was 2,7-dibromocryptolepine (7); a single oral dose of 20 mg/Kg suppressed parasitaemia and increased the mean survival time to 13.6 days compared with 8.4 days for untreated controls. In addition, four huperzine derivatives (9-12) were shown to have in vitro antitrypanosomal activities with IC50 values from 303-377 nM.
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Gissi, Danilo Soares. "Phylogeny of Phlegmariurus (Lycopodiaceae) focusing on Brazilian endemic species." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-18052017-150806/.

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Phlegmariurus is the most abundant genus of Lycopodiaceae in Brazil with 40 species, 24 of which are endemic, occurring mainly in the Atlantic Rainforest and Rocky Fields (“Campos Rupestres”) in the Espinhaço range. Some phylogeny works with the group had already been carried out, but not including a representative sample of the Brazilian species. Thus, we performed a molecular phylogeny of Phlegmariurus species endemic in Brazil using three molecular markers of cpDNA. Phlegmariurus showed to be monophyletic, including two clades, one Neotropical and another Paleotropical. All the Brazilian species sampled appeared in the Neotropical clade. The endemic species appeared in several clades alongside Andean species. Epiphytism and the microphylls differentiation were optimized at the obtained clade and they appeared several times in the evolutionary history of the group
Phlegmariurus é o gênero mais abundante de Lycopodiaceae no Brasil com 40 espécies, sendo 24 destas endêmicas, ocorrendo principalmente na Mata Atlântica e Campos Rupestres da Cadeia do Espinhaço. Alguns trabalhos de filogenia com o grupo já haviam sido realizados, contudo sem incluir uma amostragem representativa das espécies brasileiras. Dessa forma, realizamos a filogenia molecular das espécies de Phlegmariurus endêmicas do Brasil utilizando três marcadores moleculares de cpDNA. Phlegmariurus se mostrou monofilético, incluindo dois clados, um Neotropical e outro Paleotropical. Todas as espécies brasileiras amostradas apareceram no clado neotropical. As espécies endêmicas apareceram em vários clados em meio as espécies andinas. O epifitismo e a diferenciação dos microfilos foram otimizados nos clados obtidos e indicaram que essas características surgiram várias vezes na história evolutiva do grupo
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Kessler, Eduardo. "Esporófito de Huperzia mandiocana (Raddi) Trevisan (Lycopodiaceae)." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/92913.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pos-Graduação em Biologia Vegetal, Florianópolis, 2009.
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Lycopodiaceae inclui quatro gêneros, Huperzia distingüe-se dos outros três gêneros por apresentar, entre outras características, caules ramificados isotomicamente e esporofilos semelhantes às folhas vegetativas. Huperzia mandiocana é uma epífita ocorrente nas florestas dos Estados da Bahia, Minas Gerais, São Paulo, Rio de Janeiro, Paraná, Santa Catarina, Rio Grande do Sul, bem como no Paraguai e Norte da Argentina, em altitudes entre 200-1000 m, com as menores altitudes na parte Sul da área de ocorrência junto ao domínio da Mata Atlântica. Na literatura não há registro sobre aspectos morfoanatômicos do esporófito (caule, raiz, esporofilo e esporângio) de H. mandiocana, assim este é o objetivo do presente estudo, incluindo também dados sobre ontogênese. Esporófitos de H. mandiocana foram coletados no Morro do Caçador (Florianópolis, Santa Catarina, Brasil), entre as coordenadas 753991 - 6959613 e 754450 - 6959380 UTM (Lat. 27º 27`30" e Long. 48º25`30"), sendo utilizadas caule, raiz, esporofilos e esporângios em distintas fases de desenvolvimento. O esporófito é ereto e fixa-se ao tronco do forófito por raízes adventícias. O ápice caulinar é formado por túnica e corpo que originam tecidos constituintes dos esporofilos e esporângios. A túnica forma o tecido de revestimento destas duas estruturas, mas também origina tecidos clorofilados dos esporofilos e todos os tecidos esporangiais. O corpo origina o tecido provascular e o meristema fundamental, que formam os tecidos vasculares do caule e esporofilos, o córtex caulinar e o parênquima perivascular do esporofilo respectivamente. As raízes têm origem no periciclo caulinar e seguem, no sentido basípeto, através do córtex paralelamente ao estelo, emergem em tufos na base caulinar. Estas raízes, além da absorção, servem para sustentar o caule ereto, pois são constituídas por abundante tecido esclerenquimático. A espécie é isofila, há apenas um tipo de folha (esporofilo), na base da qual está o esporângio; a folha é microfila tem uma só nervura e não ramificadas. O esporofilo é hipoestomático, com estômatos anomocíticos; a epiderme é uniestratificada, com cutícula espessa. O mesofilo é constituído por clorênquima, com células lobadas, e parênquima aclorofilado. O esporângio origina-se da túnica e quando maduro é reniforme, constituído por epiderme, com paredes espessadas, endotécio, tapete e um único lóculo contendo esporos triletes e de superfície ornamentada.
Lycopodiaceae includes four genera, Huperzia distinguishes itself from the other three genera, among other features, because stems is branched and isotonic sporophyll (with axillary sporangia) similar to vegetative leaves. Huperzia mandiocana is an epiphyte occurring in the forests from Bahia, Minas Gerais, Sao Paulo, Rio de Janeiro, Parana, Santa Catarina, Rio Grande do Sul States, as well as in Paraguay and northern Argentina. It is located at altitudes between 200-1000 m, with the lowest altitudes in the southern area of occurrence along the Atlantic Forest domain. There are no published records on anatomical features of H. mandiocana sporophyte (stem, root, leaf and sporangium), so this is the purpose of this study, including also data on ontogeny. Huperzia mandiocana sporophytes were collected at the "Morro do Caçador" (Florianópolis, Santa Catarina, Brazil), between coordinates 753,991 to 6,959,613 and 754,450 to 6,959,380 UTM (Lat. 27 º 27 '30 "and Long. 48 º 25' 30") and the shoot, root, sporophyll and sporangia in various development stages were analysed. The sporophyte is straight and it is fixed upon the trunk of the host tree by adventitious roots. The shoot apex consists of tunica and corpus, originating tissues of sporophyll and sporangium. The tunica forms the outermost tissue of these two structures, but also creates chlorophyllous tissues of sporophyll and all sporangia tissues. The corpus originates provascular and ground meristem, which form the vascular tissues of stem and sporophyll, the stem cortical parenchyma and perivascular parenchyma. The roots are originated from pericycle in the stem and they followed in the basipetal direction through the cortex parallelly to the stele and they emerge in tufts at the base stem. Besides to absorption, these roots also to sustain the stem erect, they are composed of abundant sclerenchyma. The species is homophily, only one type of leaf (sporophyll) and sporangium is on its basis; sporophyll have only one rib, without branches. The sporophyll is hypostomatic and stomata anomocytic, the epidermis is uniseriate and the cuticle is thick. The mesophyll is consisted of lobed chlorenchyma cells and ground parenchyma. The mature sporangium arises from tunica and kidney-shaped, it´s constituted of epidermis, with thick walls, endotecium, tapetum and only one locule that containing trilete spores and ornamented surface.
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Lunardi, Paula Santana. "Perfil da ativação dos astrócitos em diferentes modelos biológicos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/101643.

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Apesar de representarem cerca de 50% de todas as células do encéfalo humano, as células da glia foram negligenciadas pela Doutrina do Neurônio, no início do século XX, por não serem excitáveis e por não se comunicarem como os neurônios. Durante um longo período, os estudos sobre os astrócitos se restringiam a suas funções de suporte do SNC. Atualmente se sabe que os astrócitos expressam receptores para uma variedade de neurotransmissores, como por exemplo, receptores colinérgicos nicotínicos, sugerindo possíveis mecanismos de resposta aos sinais enviados pela atividade neuronal, de modo variável e dinâmico, espontaneamente ou dependente da atividade neuronal e ativado pela alteração dos níveis intracelulares de Ca2+. Entretanto, os mecanismos específicos que explicam como essas células podem ser ativadas e qual sua contribuição para funcionamento do SNC ainda não estão totalmente esclarecidos. A secreção da proteína trófica S100B pelo astrócito pode ser um exemplo de comunicação celular, bem como também marcador biológico para diversas doenças. O nosso grupo já mostrou o envolvimento de diversos sistemas neuronais na modulação da secreção da proteína S100B. Um outro exemplo de comunicação é a liberação de gliotransmissores e a influência aguda astrocítica na transmissão sináptica. O objetivo dessa tese foi investigar se ativação do sistema colinérgico modula a secreção da proteína S100B em culturas primárias de astrócitos. Ainda, investigamos o uso da optogenética para o estudo da gliotransmissão em fatias de hipocampo. As culturas foram tratadas com inibidores da acetilcolinesterase (huperzina-A e tacrina), agonistas (acetiltiocolina, nicotina e carbacol) e antagonistas (mecamilamina e escopolamina) colinérgicos incubados durante 1 e 24 h. Os estudos em optogenética partiram primeiramente da caracterização do sistema cre/lox através da análise da expressão das proteínas de interesse, seletiva para astrócitos, por imunohistoquímica. Os resultados do primeiro estudo mostraram que a huperzina-A aumentou a secreção de S100B em culturas primárias de astrócitos, assim como o tratamento com nicotina; no segundo, discutiu-se as limitações metodológicas quanto a especificidade das proteínas e alteração da fisiologia dos astrócitos. Os resultados obtidos nessa tese ressaltam para a importância do conhecimento da fisiologia do astrócito, contribuindo para o entendimento de um possível mecanismo de ativação colinérgico dos astrócitos em promover secreção de S100B. Também é preciso ressaltar a relevância de novas metodologias que ajudam a descrever melhor o papel dos astrócitos na atividade sináptica.
Although about half of the brain cells are glial cells, the Neuron Doctrine has neglected them, at the beginning of 20th century, because they were not excitable and also, they were unable to communicate as neurons. For a long time, the studies about astrocytes functions were limited to trophic and metabolic support to neurons by which providing for the homeostasis of the nervous system. A variety of studies have been shown the expression of different neurotransmitters receptors in astrocytes, for instance, nicotinic receptors, suggesting the possibility of astrocytic response to neuronal activity. This response is variable and dynamic and mostly can be activated by changes at the intracellular calcium levels. However, the specific mechanisms of astrocytic Ca2+ excitability and how this process could contribute to CNS functioning are still unclear. The S100B secretion could be an example of cellular communication, as well as biomarker for diverse diseases. S100B is calcium binding protein, produced and secreted mainly by astrocytes. Our group has already demonstrated the relevance of various neuronal systems mediating the S100B secretion. Another astrocytic form of communication could be the release of gliotransmitters and the acute influence at synaptic transmission. The aim of this thesis was to investigate whether cholinergic system activation could modulate S100B secretion in primary astrocytes cultures. Moreover, we investigated the optogenetic properties as a tool for gliotransmission studies in hippocampal slices. The astrocytes cultures were treated with acetylcolinesterase inhibitors (huperzine-A and tacrine), agonists (acetylthiocholine, nicotine and carbachol) and antagonists (mecamylamine and scopolamine) for 1 and 24h. The optogenetic studies were conducted, firstly, from the cre/lox characterization of protein expression, selectively for astrocytes, by immunohistochemistry. The first study results showed that huperzine-A increased S100B secretion, as well as nicotine; in the second study, we have discussed the main methodological limitations concerning the protein specificity and astrocytes physiology changes. These results raise the importance of astrocytes functions investigations, especially S100B secretion, contributing for the first time to the understanding of astrocytes excitability likely trough nicotinic system activation. In addition, it is worthy to note that new methodologies are relevant and can help us in a better description of astrocytes role during synaptic activity and brain functioning.
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Books on the topic "Huperzine"

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Bagchi, Debasis, Jean Barilla, and Bagchi D. Huperzine A: Boost Your Brain Power. McGraw-Hill, 1999.

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Huperzine A: What You Need to Know. Avery, 1999.

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Book chapters on the topic "Huperzine"

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Lian, Wen-Wen, Ai-Lin Liu, and Guan-Hua Du. "Huperzine A." In Natural Small Molecule Drugs from Plants, 271–75. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-8022-7_45.

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Hanin, Israel, Xi Can Tang, and Alan P. Kozikowski. "Clinical and Preclinical Studies with Huperzine." In Cholinergic Basis for Alzheimer Therapy, 305–13. Boston, MA: Birkhäuser Boston, 1991. http://dx.doi.org/10.1007/978-1-4899-6738-1_32.

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Tang, Xi Can, Zhi Qi Xiong, Bo Chu Qian, Zhi Fang Zhou, and Ci Lu Zhang. "Cognition Improvement by Oral Huperzine A: A Novel Acetylcholinesterase Inhibitor." In Alzheimer Disease, 113–19. Boston, MA: Birkhäuser Boston, 1994. http://dx.doi.org/10.1007/978-1-4615-8149-9_20.

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Bhatnagar, Somika, Yuan Qing Deborah Hong, Guang Yuan Wang, and Yan Hong. "In Vivo and In Vitro Studies on Huperzine A Producing Ferns." In Biotechnology and Sustainable Agriculture 2006 and Beyond, 397–98. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-6635-1_63.

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Han, Yifan, and Xican Tang. "Preclinical and Clinical Progress with Huperzine A: A Novel Acetylcholinesterase Inhibitor." In Alzheimer Disease, 245–50. Boston, MA: Birkhäuser Boston, 1997. http://dx.doi.org/10.1007/978-1-4612-4116-4_36.

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Saxena, Ashima, Alan P. Kozikowski, Shaomeng Wang, Giuseppe Campiani, Qingjie Ding, and B. P. Doctor. "Characterization of C-10 Substituted Analogues of Huperzine A as Inhibitors of Cholinesterases." In Advances in Behavioral Biology, 601–5. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5337-3_85.

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Orhan, Ilkay Erdogan, and F. Sezer Senol. "Alkaloids and Inhibitory Effects Against Enzymes Linked to Neurodegenerative Diseases (Physostigmine, Galanthamine, Huperzine, etc.)." In Natural Products, 1525–39. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-22144-6_23.

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Ved, H. S., J. M. Best, J. R. Dave, and B. P. Doctor. "Comparative Inhibition of Acetylcholinesterase by Tacrine, Physostigmine and Huperzine in the Adult Rat Brain." In Enzymes of the Cholinesterase Family, 477–78. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4899-1051-6_102.

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Silman, Israel, Michal Harel, Mia Raves, and Joel L. Sussman. "Crystallographic Studies on Complexes of Acetylcholinesterase with the Natural Cholinesterase Inhibitors Fasciculin and Huperzine A." In Advances in Behavioral Biology, 523–30. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5337-3_75.

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Zhu, Da-Yuan, Chang-Heng Tan, and Yi-Ming Li. "The Overview of Studies on Huperzine A: A Natural Drug for the Treatment of Alzheimer's Disease." In Medicinal Chemistry of Bioactive Natural Products, 143–82. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2006. http://dx.doi.org/10.1002/0471739340.ch4.

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Reports on the topic "Huperzine"

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Myers, Todd M., Wei Sun, Ashima Saxena, Bhupendra P. Doctor, Andrew J. Bonvillain, and Matthew G. Clark. Huperzine A: Behavioral and Pharmacological Evaluation in Rhesus Monkeys. Fort Belvoir, VA: Defense Technical Information Center, June 2008. http://dx.doi.org/10.21236/ada501469.

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