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Maximilian Weigend - One of the best experts on this subject based on the ideXlab platform.
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the geometry of gender hyper diversification of sexual systems in Urtica l Urticaceae
Cladistics, 2018Co-Authors: Bernadette Grosseveldmann, Maximilian WeigendAbstract:Urtica L. (Urticaceae) is generally reported as a genus of monoecious and dioecious taxa. However, the gender information found in the literature does not at all reflect the actual diversity of gender patterns in Urtica. Dioecy appears to be truly absent from Urtica, but otherwise there has been a major diversification in the geometry of gender and no comparable patterns exist in other plant groups. Thus, we here define technical terms for all unique architectural types of monoecy found in Urtica and closely related genera and reconstruct the ancestral gender states in a Bayesian framework. Our studies are based on a near-comprehensive sampling, including 61 of the 63 Urtica species recognized. We report polygamy, two types of gynodioecy and five different architectural types of monoecy. A total of 15 switches appear to have taken place within the genus. Although gender characteristics have diversified strongly, they are relatively conserved within clades. Monoecy is the predominant sexual system within Urtica and specifically basiandrous monoecy (i.e. basal inflorescence branches of each individual male only, apical branches female) is the most widespread type, reported for 11 different clades. In particular, it characterizes the basally branching pilulifera-clade and the sister genus Zhengyia, and may thus represent the plesiomorphic condition for Urtica. Gender distribution and gross morphology appear to evolve largely independently from each other and gender distribution is largely independent of growth habit. However, polygamous taxa are most common amongst rhizomatous perennials (one-third of the taxa).
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The geometry of gender: hyper‐diversification of sexual systems in Urtica L. (Urticaceae)
Cladistics, 2017Co-Authors: Bernadette Grosse-veldmann, Maximilian WeigendAbstract:Urtica L. (Urticaceae) is generally reported as a genus of monoecious and dioecious taxa. However, the gender information found in the literature does not at all reflect the actual diversity of gender patterns in Urtica. Dioecy appears to be truly absent from Urtica, but otherwise there has been a major diversification in the geometry of gender and no comparable patterns exist in other plant groups. Thus, we here define technical terms for all unique architectural types of monoecy found in Urtica and closely related genera and reconstruct the ancestral gender states in a Bayesian framework. Our studies are based on a near-comprehensive sampling, including 61 of the 63 Urtica species recognized. We report polygamy, two types of gynodioecy and five different architectural types of monoecy. A total of 15 switches appear to have taken place within the genus. Although gender characteristics have diversified strongly, they are relatively conserved within clades. Monoecy is the predominant sexual system within Urtica and specifically basiandrous monoecy (i.e. basal inflorescence branches of each individual male only, apical branches female) is the most widespread type, reported for 11 different clades. In particular, it characterizes the basally branching pilulifera-clade and the sister genus Zhengyia, and may thus represent the plesiomorphic condition for Urtica. Gender distribution and gross morphology appear to evolve largely independently from each other and gender distribution is largely independent of growth habit. However, polygamous taxa are most common amongst rhizomatous perennials (one-third of the taxa).
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Weeding the nettles IV: A redefinition of Urtica incisa and allies in New Zealand and Australia, including the segregation of two new species Urtica sykesii and U. perconfusa
Phytotaxa, 2016Co-Authors: Bernadette Grosse-veldmann, Barry J. Conn, Maximilian WeigendAbstract:Taxon differentiation in Urtica from Australia and New Zealand initially appears to be uncomplicated, with taxa being easy to distinguish. However, a revision of the type material, more recent collections and a comparison of Australian and New Zealand material shows that three of the names are misapplied. Urtica gracilis (as U. dioica subsp. gracilis, North America) has been reported as introduced to New Zealand, but molecular data retrieve the corresponding specimens with the other NZ-species and we argue that they belong to the polygamous Australian species Urtica incisa. A critical revision of the protologues and type collections reveals that the names Urtica incisa , originally described from mainland Australia, and U. incisa var. linearifolia from Tasmania, have been misapplied to New Zealand taxa. Both New Zealand “ Urtica linearifolia ” and “ U. incisa ” represent unnamed taxa and are here formally described as Urtica perconfusa and Urtica sykesii , respectively. Urtica perconfusa corresponds to what is erroneously known as U. linearifolia. Urtica sykesii is an overlooked species, erroneously interpreted as U. incisa in New Zealand. It may be differentiated from U. incisa Poir. by its smaller, deltoid leaf lamina with a truncate to subcordate base (versus truncate to cuneate), fewer leaf teeth (9–12 on each side rather than 14–20 in U. incisa ) and smaller plant size (20–60 cm rather than 60–200 cm in U. incisa ). We found evidence for the presence of true introduced U. dioica subsp. dioica in New Zealand, but not for U. gracilis . Rather, New Zealand specimens assigned to the putatively introduced northern hemisphere U . gracilis belong to U. incisa as described from Australia. Typifications for the species treated here are provided, including an updated key to the Australian and New Zealand taxa. There are thus six native species of Urtica in New Zealand, four of them endemic, and two also indigenous in Australia.
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Weeding the Nettles II: A delimitation of "Urtica dioica L." (Urticaceae) based on morphological and molecular data, including a rehabilitation of Urtica gracilis Ait.
Phytotaxa, 2014Co-Authors: Tilo Henning, Alexander Monro, Bernadette Grosse-veldmann, Dietmar Quandt, Maximilian WeigendAbstract:The taxonomy of subcosmopolitan Urtica dioica L. s.l. is problematic. Recent floras recognize Urtica dioica as a subcosmopolitan species ranging throughout the entire holarctic region and also South Africa and New Zealand. Numerous infraspecific taxa have been proposed, especially in western Eurasia. There is only weak character differentiation, with floral and fruit morphology largely uniform, details of leaf morphology and indumentum are therefore primarily used for species delimitation, together with some characters of gender distribution and growth habit. The present study addresses the enigmatic relationships of the infraspecific taxa in Urtica dioica with a special emphasis on the monoecious, American representatives of Urtica dioica s.l. The study is based on extensive field and herbarium studies, molecular data and the experimental cultivation of all relevant forms. Infraspecific taxa currently assigned to U. dioica are retrieved mainly on two separate clades, one comprising the predominantly polygamous western Eurasian and African taxa (all subspecies and varieties sampled), the other comprising the monoecious American taxa. Monoecious American representatives of “ Urtica dioica” and closely allied taxa ( U. aquatica, U. mollis ) are retrieved as a monophyletic group sister to a clade with East Asian and Australasian species, this clade is then retrieved as sister to the western and central Eurasian and African taxa of U. dioica . We therefore advocate the removal of the American representatives of this group from Urtica dioica and their placement as infraspecific taxa under Urtica gracilis . The following new names are consequently proposed: Urtica gracilis subsp. gracilis (for Urtica dioica subsp. gracilis ), Urtica gracilis subsp. holosericea, comb. nov . (for Urtica dioica subsp. holosericea ), Urtica gracilis subsp. aquatica , comb . & stat. nov . (for Urtica aquatica ), Urtica gracilis subsp. mollis , comb . & stat. nov . (for Urtica mollis ). Additionally, we describe a new subspecies from Peru under the name Urtica gracilis subsp. incaica . The literature report of Urtica gracilis ( dioica subsp. gracilis ) as an introduced weed in New Zealand is shown to be erroneous – the corresponding specimens belong to Australian Urtica incisa . Based on gross morphology close affinities have been proposed between a range of Australasian, Asian, North American and European infraspecific taxa, all of these can be shown to be erroneous.
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phytochemical phylogenetic and anti inflammatory evaluation of 43 Urtica accessions stinging nettle based on uplc q tof ms metabolomic profiles
Phytochemistry, 2013Co-Authors: Mohamed A Farag, Maximilian Weigend, Federico Luebert, Grischa Brokamp, Ludger A WessjohannAbstract:Several species of the genus Urtica (especially Urtica dioica, Urticaceae), are used medicinally to treat a variety of ailments. To better understand the chemical diversity of the genus and to compare different accessions and different taxa of Urtica, 63 leaf samples representing a broad geographical, taxonomical and morphological diversity were evaluated under controlled conditions. A molecular phylogeny for all taxa investigated was prepared to compare phytochemical similarity with phylogenetic relatedness. Metabolites were analyzed via UPLC-PDA-MS and multivariate data analyses. In total, 43 metabolites were identified, with phenolic compounds and hydroxy fatty acids as the dominant substance groups. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) provides a first structured chemotaxonomy of the genus. The molecular data present a highly resolved phylogeny with well-supported clades and subclades. U. dioica is retrieved as both para- and polyphyletic. European members of the U. dioica group and the North American subspecies share a rather similar metabolite profile and were largely retrieved as one, nearly exclusive cluster by metabolite data. This latter cluster also includes - remotely related - Urtica urens, which is pharmaceutically used in the same way as U. dioica. However, most highly supported phylogenetic clades were not retrieved in the metabolite cluster analyses. Overall, metabolite profiles indicate considerable phytochemical diversity in the genus, which largely falls into a group characterized by high contents of hydroxy fatty acids (e.g., most Andean-American taxa) and another group characterized by high contents of phenolic acids (especially the U. dioica-clade). Anti-inflammatory in vitro COX1 enzyme inhibition assays suggest that bioactivity may be predicted by gross metabolic profiling in Urtica.
Mukerrem Kaya - One of the best experts on this subject based on the ideXlab platform.
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effect of usage Urtica dioica l on microbiological properties of sucuk a turkish dry fermented sausage
Food Control, 2004Co-Authors: Muhammet Irfan Aksu, Mukerrem KayaAbstract:Abstract The effect of dried-ground Urtica dioica L. on microbiological characteristics of Turkish dry-fermented sausage (sucuk) were investigated. Dried-ground Urtica dioica L. was added to sucuk batters by the rate of 0%, 1%, 3% and 5%, and microbiological analysis were made on the 0, 3, 7, 10 and 14 days of ripening period. According to the results, both the level of Urtica dioica L. and ripening time had a significant effects on the total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus, yeast-mould and Enterobacteriaceae counts (p
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Effect of usage Urtica dioica L. on microbiological properties of sucuk, a Turkish dry-fermented sausage
Food Control, 2004Co-Authors: Muhammet Irfan Aksu, Mukerrem KayaAbstract:Abstract The effect of dried-ground Urtica dioica L. on microbiological characteristics of Turkish dry-fermented sausage (sucuk) were investigated. Dried-ground Urtica dioica L. was added to sucuk batters by the rate of 0%, 1%, 3% and 5%, and microbiological analysis were made on the 0, 3, 7, 10 and 14 days of ripening period. According to the results, both the level of Urtica dioica L. and ripening time had a significant effects on the total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus , yeast-mould and Enterobacteriaceae counts ( p Urtica dioica L. had a significant effects on the counts of total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus , yeast-mould and Enterobacteriaceae ( p Enterobacteriaceae count were also found to be under the detectable level ( Urtica dioica L.
Muhammet Irfan Aksu - One of the best experts on this subject based on the ideXlab platform.
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effect of usage Urtica dioica l on microbiological properties of sucuk a turkish dry fermented sausage
Food Control, 2004Co-Authors: Muhammet Irfan Aksu, Mukerrem KayaAbstract:Abstract The effect of dried-ground Urtica dioica L. on microbiological characteristics of Turkish dry-fermented sausage (sucuk) were investigated. Dried-ground Urtica dioica L. was added to sucuk batters by the rate of 0%, 1%, 3% and 5%, and microbiological analysis were made on the 0, 3, 7, 10 and 14 days of ripening period. According to the results, both the level of Urtica dioica L. and ripening time had a significant effects on the total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus, yeast-mould and Enterobacteriaceae counts (p
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Effect of usage Urtica dioica L. on microbiological properties of sucuk, a Turkish dry-fermented sausage
Food Control, 2004Co-Authors: Muhammet Irfan Aksu, Mukerrem KayaAbstract:Abstract The effect of dried-ground Urtica dioica L. on microbiological characteristics of Turkish dry-fermented sausage (sucuk) were investigated. Dried-ground Urtica dioica L. was added to sucuk batters by the rate of 0%, 1%, 3% and 5%, and microbiological analysis were made on the 0, 3, 7, 10 and 14 days of ripening period. According to the results, both the level of Urtica dioica L. and ripening time had a significant effects on the total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus , yeast-mould and Enterobacteriaceae counts ( p Urtica dioica L. had a significant effects on the counts of total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus , yeast-mould and Enterobacteriaceae ( p Enterobacteriaceae count were also found to be under the detectable level ( Urtica dioica L.
Haleh Akhavanniaki - One of the best experts on this subject based on the ideXlab platform.
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antioxidant and apoptotic effects of an aqueous extract of Urtica dioica on the mcf 7 human breast cancer cell line
Asian Pacific Journal of Cancer Prevention, 2013Co-Authors: Sadegh Fattahi, Zeinab Abedian, Amrollah Mostafazadeh, Roghayeh Pourbagher, Ebrahim Zabihi, A. Mokhtari Ardekani, Haleh AkhavanniakiAbstract:Breast cancer is the most prevalent cancer and one of the leading causes of death among women in the world. Plants and herbs may play an important role in complementary or alternative treatment. The aim of this study was to evaluate the antioxidant and anti-proliferative potential of Urtica dioica. The anti oxidant activity of an aqueous extract of Urtica dioica leaf was measured by MTT assay and the FRAP method while its anti-proliferative activity on the human breast cancer cell line (MCF-7) and fibroblasts isolated from foreskin tissue was evaluated using MTT assay. Mechanisms leading to apoptosis were also investigated at the molecular level by measuring the amount of anti and pro-apoptotic proteins and at the cellular level by studying DNA fragmentation and annexin V staining by flow cytometry. The aqueous extract of Urtica dioica showed antioxidant effects with a correlation coefficient of r 2 =0.997. Dose-dependent and anti-proliferative effects of the extract were observed only on MCF-7 cells after 72 hrs with an IC 50 value of 2 mg/ml. This anti proliferative activity was associated with an increase of apoptosis as demonstrated by DNA fragmentation, the appearance of apoptotic cells in flow cytometry analysis and an increase of the amount of calpain 1, calpastatin, caspase 3, caspase 9, Bax and Bcl-2, all proteins involved in the apoptotic pathway. This is the first time such in vitro antiproliferative effect of aqueous extract of Urtica dioica leaf has been described for a breast cancer cell line. Our findings warrant further research on Urtica dioica as a potential chemotherapeutic agent for breast cancer.
Olov Sterner - One of the best experts on this subject based on the ideXlab platform.
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Antioxidant and anti-inflammatory effects of Urtica pilulifera extracts in type2 diabetic rats
Journal of ethnopharmacology, 2012Co-Authors: Dina M. Abo-elmatty, Soha S. Essawy, Jihan M. Badr, Olov SternerAbstract:Ethnopharmacological relevance: "Urtica pilulifera has been traditionally used in Egyptian system as an herbal remedy to be a diuretic, antiasthmatic, anti-inflammatory, hypoglycemic, hemostatic, antidandruff and astringent" Aim of the study: To evaluate the potential effects of ethyl acetate (EA), chloroform (CHLOR) and hexane (HEXA) extracts of Urtica piluliferaas oral anti-diabetic agents as well as to evaluate their possible antioxidant and anti-inflammatory effects in type2 diabetic rat model. Material and methods: Type2 diabetes was induced by a high fat diet and low dose streptozotocin (STZ). Diabetic adult male albino rats were allocated into groups and treated according to the following schedule; Pioglitazone HCL (PIO), EA, CHLOR and HEXA extracts of Urtica piluilifera at two doses of 250 and 500 mg/ kg were used. In addition, a normal control group and a diabetic control one were used for comparison. Blood glucose, insulin resistance, antioxidant enzymes, 8-hydroxy-2-deoxyguanosine (8-OHdG) as well as C-reactive protein and tumor necrosis factor-a levels were evaluated. Results: EA and CHLOR extracts of Urtica pilulifera exhibited a significant hypoglycemia associated with antioxidant and anti-inflammatory effects in diabetic rats; however, HEXA extract showed no beneficial effect. These activities are responsible, at least partly, for improvements that have been seen in hyperglycemia and insulin resistance of diabetic rats. Conclusion: Our results encourage the traditional use of Urtica pilulifera extract as an antioxidant and anti-inflammatory agent as an additional therapy of diabetes. (C) 2012 Elsevier Ireland Ltd. All rights reserved. (Less)
