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Herbs
Kinds of Herbs Terms modified by Herbs Selected AbstractsEffects of earthquake and cyclone sequencing on landsliding and fluvial sediment transfer in a mountain catchmentEARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2008Guan-Wei Lin Abstract Patterns and rates of landsliding and fluvial sediment transfer in mountain catchments are determined by the strength and location of rain storms and earthquakes, and by the sequence in which they occur. To explore this notion, landslides caused by three tropical cyclones and a very large earthquake have been mapped in the Chenyoulan catchment in the Taiwan Central Range, where water and sediment discharges and rock strengths are well known. Prior to the MW 7·6 Chi-Chi earthquake in 1999, storm-driven landslide rates were modest. Landslides occurred primarily low within the landscape in shallow slopes, reworking older colluvial material. The Chi-Chi earthquake caused wide-spread landsliding in the steepest bedrock slopes high within the catchment due to topographic focusing of incoming seismic waves. After the earthquake landslide rates remained elevated, landslide patterns closely tracking the distribution of coseismic landslides. These patterns have not been strongly affected by rock strength. Sediment loads of the Chenyoulan River have been limited by supply from hillslopes. Prior to the Chi-Chi earthquake, the erosion budget was dominated by one exceptionally large flood, with anomalously high sediment concentrations, caused by typhoon Herb in 1996. Sediment concentrations were much higher than normal in intermediate size floods during the first 5 years after the earthquake, giving high sediment yields. In 2005, sediment concentrations had decreased to values prevalent before 1999. The hillslope response to the Chi-Chi earthquake has been much stronger than the five-fold increase of fluvial sediment loads and concentrations, but since the earthquake, hillslope sediment sources have become increasingly disconnected from the channel system, with 90 per cent of landslides not reaching into channels. Downslope advection of landslide debris associated with the Chi-Chi earthquake is driven by the impact of tropical cyclones, but occurs on a time-scale longer than this study. Copyright © 2008 John Wiley & Sons, Ltd. [source] Herbal medicine and epilepsy: Proconvulsive effects and interactions with antiepileptic drugsEPILEPSIA, Issue 3 2008Noah Samuels Summary The use of complementary and alternative medicine is on the rise, including among patients with epilepsy. Herbal medicine, one of the most popular forms of CAM, is considered to be both safe and effective by most consumers. Yet many herbs may increase the risk for seizures, through intrinsic proconvulsant properties or contamination by heavy metals, as well as via effects on the cytochrome P450 enzymes and P-glycoproteins, altering antiepileptic drug (AED) disposition. Herb,drug interactions may be difficult to predict, especially since the quality and quantity of active ingredients are often unknown. Since most patients do not inform their physicians that they are taking herbal medicines, health care professionals must initiate a dialogue in order to prevent complications with the combined regimen. At the same time, further research is required regarding the effect of herbs on seizure activity and interactions with AED treatment. [source] Herb,drug interactions: Review and assessment of report reliabilityBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 5 2001Adriane Fugh-Berman Aims, The aim of this systematic review was to assess the published clinical evidence on interactions between herbal and conventional drugs. Methods, Four electronic databases were searched for case reports, case series or clinical trials of such interactions. The data were extracted and validated using a scoring system for interaction probability. Results, One hundred and eight cases of suspected interactions were found. 68.5% were classified as ,unable to be evaluated', 13% as ,well-documented' and 18.5% as ,possible' interactions. Warfarin was the most common drug (18 cases) and St John's wort the most common herb (54 cases) involved. Conclusion, Herb,drug interactions undoubtedly do occur and may put individuals at risk. However our present knowledge is incomplete and more research is urgently needed. [source] Cosmeceuticals Containing Herbs: Fact, Fiction, and FutureDERMATOLOGIC SURGERY, Issue 2005Carl Thornfeldt MD Background. Modern medicine is rooted in ethnobotanical traditions using indigenous flora to treat symptoms of human diseases or to improve specific aspects of the body condition. Herbal medicine is now used by over half of the American population. Yet the American medical community generally lacks knowledge of the function, metabolism, interaction, adverse reactions, and preparation of herbal products. Objective. Because over 60 botanicals are marketed in cosmeceutical formulations, dermatologists need to obtain working knowledge of the major botanicals. The preparation, traditional uses, mechanisms of action, human clinical data, adverse reactions, and interactions all impact herbal efficacy and are discussed below. Method. English-language medical journal and symposium searches. Results. The most important botanicals pertaining to dermatologic uses, such as cosmeceuticals, include teas, soy, pomegranate, date, grape seed, Pycnogenol, horse chestnut, German chamomile, curcumin, comfrey, allantoin, and aloe. All are documented to treat dermatologic conditions. Only green and black tea, soy, pomegranate, and date have published clinical trials for the treatment of parameters of extrinsic aging. Conclusions. Preparation of botanical-based cosmeceuticals is complex. Very few of these products are supported by evidence-based science. CARL THORNFELDT, MD, FAAD, HAS INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Use of Alternative Therapies by Patients Undergoing Surgery for Nonmelanoma Skin CancerDERMATOLOGIC SURGERY, Issue 6 2002Scott M. Dinehart MD background. The use of alternative therapies is becoming increasingly common and may result in unwanted side effects and drug interactions. objective. To determine the frequency of alternative medicine use by patients undergoing Mohs surgery for nonmelanoma skin cancer. methods. A written survey concerning use of alternative therapies was given to patients undergoing Mohs surgery for nonmelanoma skin cancer. A follow-up telephone survey was used to clarify positive responses. results. Thirty-six of 192 (18.8%) patients with nonmelanoma skin cancer reported using some type of alternative therapy. Almost all patients were using these therapies for conditions unrelated to their nonmelanoma skin cancer. Herbs and botanicals were the most common type of alternative therapy utilized. conclusion. Physicians performing Mohs surgery should be aware that a significant number of their patients use alternative therapies. Since most patients do not readily volunteer information about alternative medicine usage, specific steps should be taken to obtain this information. [source] Nutraceuticals: The Complete Encyclopedia of Supplements, Herbs, Vitamins, and Healing FoodsFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 4 2001E Ernst [source] Herbs, Botanicals and TeasFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 4 2000E Ernst [source] Interaction of Drugs and Chinese Herbs: Pharmacokinetic Changes of Tolbutamide and Diazepam Caused by Extract of Angelica dahuricaJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2000KAZUHISA ISHIHARA The inhibitory effects of Angelica dahurica root extract on rat liver microsomal cytochrome P450 and drug-drug interactions were studied. The 2,- and 16,-hydroxylase activity of testosterone were most strongly inhibited, with 17.2% and 28.5% of their activity remaining, respectively, after oral administration of A. dahurica extract at a 1 g kg,1 dose. 6,-Hydroxylase activity was also inhibited, with 70% of its activity remaining, under the same conditions. In addition, treatment with the extract inhibited the metabolism of tolbutamide, nifedipine and bufuralol. These results showed that the extract inhibited the various isoforms of cytochrome P450 such as CYP2C, CYP3A and CYP2D1. The A. dahurica extract delayed elimination of tolbutamide after intravenous administration at a 10 mg kg,1 dose to rats. Thus, the extract altered the liver intrinsic clearance. It had little effect, however, on the pharmacokinetic parameters of diazepam after intravenous administration at 10 mg kg,1. Since diazepam showed high clearance, it underwent hepatic blood flow rate-limited metabolism. Therefore, the change of intrinsic clearance had little effect on hepatic clearance. However, the Cmax value after oral administration of diazepam with extract treatment was four times that with non-treatment. It was suggested that the first-pass effect was changed markedly by the extract. High-dose (1 g kg,1), but not low dose (0.3 g kg,1), administration of A. dahurica extract increased significantly the duration of rotarod disruption following intravenous administration of diazepam at 5 mg kg,1. It was concluded that administration of A. dahurica extract has the potential to interfere with the metabolism, by liver cytochrome P450, of other drugs. [source] Healing Herbs and Dangerous Doctors: "Fruit Fever" and Community Conflicts with Biomedical Care in Northeast ThailandMEDICAL ANTHROPOLOGY QUARTERLY, Issue 4 2007Jen PylypaArticle first published online: 8 JAN 200 In Northeast Thailand, khai mak mai (fruit fever) is a local, ethnomedical category of illness identified by community members as untreatable by biomedical health providers. The illness is believed to be incompatible with several substances that may induce death, including fruit as well as two forms of medication associated with biomedical care: injections and intravenous solution. Consequently, fevers suspected of being khai mak mai are treated by herbalists while biomedical health services are avoided and feared. In this article, I examine local perceptions and treatment of khai mak mai. I also explore the context and consequences of concerns about the inadequacy of biomedical care, as well as the social meanings associated with the illness and the political-economic context that shapes both the meanings of, and everyday responses to, fevers suspected of being khai mak mai. [source] Needles, Herbs, Gods, and Ghosts: China, Healing, and the West to 1848 by Linda L. BarnesAMERICAN ETHNOLOGIST, Issue 4 2009C. PIERCE SALGUERO No abstract is available for this article. [source] Tyler's Herbs of Choice the therapeutic use of phytomedicinals, Dennis V.C. Awang, Publisher: CRC Press, Taylor & Francis Group, Florida USA, 3rd edn, 2009, ISBN 978-0-7890-2809-9PHYTOTHERAPY RESEARCH, Issue 9 2010Eileen Smith No abstract is available for this article. [source] Diabetes and complementary therapies: mapping the evidencePRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 7 2007K Pilkington MSc, MRPharmS Senior Research Fellow Abstract Complementary therapies are widely used by people with diabetes for the condition itself, for diabetes-related complications or for non-diabetes related problems. The aim of this review is to summarise the current research evidence on complementary therapies in the management of diabetes and resulting complications. The review draws primarily on systematic reviews conducted as part of the CAMEOL project (www.rccm.org.uk/cameol), included in the Cochrane Library or on the National Library for Health Complementary and Alternative Medicine Specialist Library (www.library.nhs.uk/cam). Searches were also carried out for studies published subsequently or on other therapies to provide an indication of overall research activity. Systematic reviews were found or conducted on a range of herbs, dietary supplements, massage, acupuncture, homoeopathy, hypnotherapy, meditation, reflexology and yoga. Individual studies were located on several other therapies. Studies addressed metabolic control, general well-being and complications. Herbs and dietary supplements continue to be the main focus of research activity. Acupuncture trials are also numerous but almost exclusively conducted in China using traditional approaches. For most other therapies, research evidence is limited by extent or quality. Overall, limited data from well-designed randomised controlled trials are available and results are difficult to translate into clinical practice. Based on promising findings, several herbs, dietary supplements, exercise or body-based therapies and acupuncture require further investigation. For most therapies, well-designed robust studies replicating small preliminary studies are required to support those involved in diabetes care in providing evidence-based advice on the safe and effective use of complementary therapies. Copyright © 2007 John Wiley & Sons. [source] The response of riparian vegetation to flood-maintained habitat heterogeneity,AUSTRAL ECOLOGY, Issue 5 2007BONNIE C. WINTLE Abstract Riparian environments are subject to the scouring and depositional effects of floods. Riparian vegetation and substrates are scoured during high flows, while litter and sediment is deposited downstream. In the Prosser and Little Swanport River catchments in south-east Tasmania, vascular plant species were surveyed in large riparian relevés. Within these relevés, 1 × 1 m subplots were placed in both flood-scoured and depositional environments. Species composition was compared between these three datasets, to investigate the importance of floods in determining species richness and species composition of riparian vegetation. Species richness and diversity were highest in areas experiencing flood scour. Herbs appear particularly reliant on the creation of gaps for colonization, and some major riparian shrub species may also require disturbance to maintain their abundance. The depositional environment tended to favour shrubs and graminoids. Given that differences in species composition are related to flood-induced features of the riparian environment, the regulation of these rivers might reduce the diversity of the riparian vegetation downstream of dams. [source] Response of the soil seed-bank of Cumberland Plain Woodland to heatingAUSTRAL ECOLOGY, Issue 1 2003SARAH J. HILL Abstract Soil was investigated in a Cumberland Plain Woodland community to determine the presence of a soil seed-bank and whether species richness and abundance of plants germinating from it were affected by heating such as that experienced in a fire. Soil samples were taken from the Holsworthy Military Area, in the south-eastern region of the Sydney Basin, New South Wales, Australia, and one of four treatments was applied; soil was heated to 80°C, 40°C, unheated or unheated with litter not removed. Sixty-eight species, representing 26 families including 11 exotic and 57 native species germinated from the soil. Herbs and grasses dominated and were in similar proportions to those surveyed in the above-ground vegetation, suggesting that the soil seed-bank reflected the current structure of the vegetation, although species composition differed. Species responded differently to heating. The seeds of some species germinated when heated at a higher temperature (80°C), particularly those from the family Fabaceae, whereas other species were more common in unheated or lightly heated samples (40°C). This suggests that fire is likely to change the species composition of the above-ground vegetation and indicates that management must ensure that species that do not germinate when heated are maintained, as well as those species that germinate following heating. A large proportion of soil seed-bank species showed low germination rates in the trials, and 112 above-ground species did not germinate in the soil samples. We do not understand whether species of these two sets do not produce a soil-stored seed-bank or whether the seed-bank has been depleted by past practices at Holsworthy. Further research is needed. [source] Anthropogenic and climatic impacts on surface pollen assemblages along a precipitation gradient in north-eastern ChinaGLOBAL ECOLOGY, Issue 5 2010Yun Zhang ABSTRACT Aim, To understand the scenarios of ,anthropogenic biomes' that integrate human and ecological systems, we need to explore the impacts of climate and human disturbance on vegetation in the past and present. Interactions among surface pollen, modern vegetation and human activities along climate and land-use gradients are tested to evaluate the natural and anthropogenic forces shaping the modern vegetation, and hence to aid the reconstruction of vegetation and climate in the past. This in turn will help with future predictions. Location, The North-east China Transect (NECT) in north-eastern China. Methods, We analysed 33 surface pollen samples and 213 quadrats across four vegetation zones along the moisture/land-use gradients of the NECT. Detrended correspondence analysis (DCA) and redundancy analysis (RDA) of 52 pollen taxa and three environmental variables were used to distinguish anthropogenic and climatic factors that affect surface pollen assemblages along the NECT. Results, The 33 surface samples are divided into four pollen zones (forest, meadow steppe, typical steppe and desert steppe) corresponding to major vegetation types in the NECT. Variations in pollen ratios of fern/herb (F/H), Artemisia/Chenopodiaceae (A/C) and arboreal pollen/non-arboreal pollen (AP/NAP) represent the vegetation and precipitation gradient along the NECT. DCA and RDA analyses suggest that surface pollen assemblages are significantly influenced by the precipitation gradient. Changes in the abundance of Chenopodiaceae pollen are related to both human activities and precipitation. Main conclusions, Surface pollen assemblages, fossil pollen records, archaeological evidence and historical documents in northern China show that a large increase of Chenopodiaceae pollen indicates human-caused vegetation degradation in sandy habitats. The A/C ratio is a good indicator of climatic aridity, but should be used in conjunction with multiple proxies of human activities and climate change in the pollen-based reconstruction of anthropogenic biomes. [source] Interactions between non-native plant species and the floristic composition of common habitatsJOURNAL OF ECOLOGY, Issue 6 2006L. C. MASKELL Summary 1We investigated the role of non-native species (neophytes) in common British plant communities using botanical data from two stratified random surveys carried out in 1990 and 1998. 2We found that from 16 851 plots surveyed in 1998 there were 123 non-native species found mostly in arable, tall grass/herb and fertile grassland habitats. Invasive non-native species, e.g. Fallopia japonica, Impatiens glandulifera and Rhododendron ponticum, were uncommon in this survey. 3Between 1990 and 1998 the total number of non-native species increased but the mean number of species per sample plot decreased. The mean cover of non-natives increased from 1.2% to 1.9%. 4There were positive spatial and temporal relationships between non-native and native species diversity. However, there was a weak negative relationship between changes in non-native cover and native diversity. 5The species composition and ecological traits of communities containing non-natives were very different from those that did not contain them. 6In the British countryside non-native species were mainly found in habitats with anthropogenic associations, high fertility, high number of ruderal species and high diversity. There is also an indication that successional shifts where competitive invasive species dominate involve non-native species. 7National-scale changes in plant community composition are likely to be closely correlated with external land-use impacts. Changes such as eutrophication, nitrogen deposition and increased fertility in infertile habitats are likely to benefit both native and non-native invasive species; however, currently these trends benefit native species much more often than non-natives. 8Non-native species are known to have significant effects on native species at local scales in many countries; however, at the landscape scale in Great Britain they are best considered as symptoms of disturbance and land-use change rather than a direct threat to biodiversity. [source] Impact of Forest Fragmentation on Understory Plant Species Richness in AmazoniaCONSERVATION BIOLOGY, Issue 2 2003Julieta Benítez-Malvido In Central Amazonia, 9 to 19 years after fragmentation, we recorded species richness and net seedling recruitment rate in forest fragments of 1, 10, and 100 ha and in continuous forest. In 1991 all seedlings 5,100 cm tall within permanent 1-m2 plots in fragments and continuous forest were counted and grouped into tree, liana, palm, and herb life-form classes. In 1993 we manually removed all seedlings that were <1 m tall from the permanent plots. Six years and 5 months later ( 1999 ), all new seedlings recruited into the plots were counted, grouped into different life forms, and classified into distinct morphospecies. The species richness of recruited tree, liana, herb, and palm seedlings was lower in forest fragments than in continuous forest, with the 1-ha fragment having the poorest species richness. The total number of recruited individuals was 40% less than that previously present for all life forms, except lianas. Liana recruitment was 7% to 500% higher than the original abundance in the forest fragments and continuous forest. In general, species similarity was higher among fragments than between fragments and continuous forest, with the 1-ha fragment being less similar. Species rank/abundance curves showed that continuous forest species in all life forms tended to disappear in forest fragments, whereas common species in forest fragments were absent from continuous forest. Overall, our results suggest that the life-form composition and structure of the regenerative plant pool in fragments were shifting toward a species-poor seedling community. Losses of understory species diversity, but especially of tree seedlings, threaten the maintenance of rainforest biodiversity and compromise future forest regeneration. Resumen: La fragmentación de las selvas tropicales afecta severamente a a los árboles de gran porte, sin embargo, su efecto sobre otros estadíos y formas de vida de las plantas es poco conocido. En la Amazonia central, de 9 a 19 años después de la fragmentación, se registró la riqueza de especies y la tasa neta de reclutamiento de plántulas en fragmentos de selva de 1, 10, y 100 ha y en selva contínua. En 1991, todas las plántulas de 5,100 cm de altura dentro de cuadrantes permanentes de 1-m2 en los fragmentos y en la selva contínua, fueron contadas y agrupadas en diferentes formas de vida: árboles, lianas, palmas y hierbas. En 1993 se removieron manualmente todas las plántulas <1 m de altura dentro de los cuadrantes. Seis años y cinco meses más tarde (1999) se contaron todas las plántulas reclutadas dentro de los cuadrantes, se agruparon en diferentes formas de vida v se clasificaron en morfoespecies distintivas. La riqueza de especies de plántulas reclutadas en todas las formas de vida fue menor en los fragmentos que en la selva contínua, con el fragmento de 1 ha presentando la menor riqueza de especies. El número total de individuos reclutados fue 40% menor que los previamente presentes para todas las formas de vida, excepto lianas. El reclutamiento de lianas fué de 7 a 500% mayor que la abundancia original en los fragmentos y en la selva contínua. En general la similitud de especies fué mayor entre fragmentos que entre fragmentos y selva contínua, con el fragmento de 1-ha siendo el menos similar. Las curvas de rango/abundancia de especies, mostraron que las especies de selva contínua en todas las formas de vida tendieron a desaparecer de los fragmentos, mientras que las especies comunes en los fragmentos estuvieron ausentes en la selva contínua. En general, nuestros resultados sugieren que la composición de formas de vida y la estructura del banco regenerativo en fragmentos tienden a convertirse en una comunidad de plántulas pobre en especies. La pérdida de diversidad de especies del sotobosque, pero especialmente de plántulas de árboles, amenaza el mantenimiento de la biodiversidad y pone en peligro la regeneración futura de la selva. [source] Impacts of a woody invader vary in different vegetation communitiesDIVERSITY AND DISTRIBUTIONS, Issue 5 2008T. J. Mason Abstract The impact of an exotic species in natural systems may be dependent not only on invader attributes but also on characteristics of the invaded community. We examined impacts of the invader bitou bush, Chrysanthemoides monilifera ssp. rotundata, in fore and hind dune communities of coastal New South Wales, Australia. We compared invader impacts on vegetation structure, richness of both native and exotic growth forms and community variability in fore and hind dunes. We found that impacts of bitou invasion were context specific: in fore dune shrublands, functionally distinct graminoid, herb and climber rather than shrub growth forms had significantly reduced species richness following bitou invasion. However, in forested hind dunes, the functionally similar native shrub growth form had significantly reduced species richness following bitou invasion. Density of vegetation structure increased at the shrub level in both fore and hind dune invaded communities compared with non-invaded communities. Fore dune ground-level vegetation density declined at invaded sites compared with non-invaded sites, reflecting significant reductions in herb and graminoid species richness. Hind dune canopy-level vegetation density was reduced at invaded compared with non-invaded sites. Bitou bush invasion also affected fore dune community variability with significant increases in variability of species abundances observed in invaded compared with non-invaded sites. In contrast, variability among all hind dune sites was similar. The results suggest that effects of bitou bush invasion are mediated by the vegetation community. When bitou bush becomes abundant, community structure and functioning may be compromised. [source] Antagonistic effects of seed dispersal and herbivory on plant migrationECOLOGY LETTERS, Issue 3 2006Mark Vellend Abstract The two factors that determine plant migration rates , seed dispersal and population growth , are generally treated independently, despite the fact that many animals simultaneously enhance plant migration rate via seed dispersal, and decrease it via negative effects of herbivory on population growth. Using extensive empirical data, we modelled the antagonistic effects of seed dispersal and herbivory by white-tailed deer on potential migration rates of Trillium grandiflorum, a forest herb in eastern North America. This novel antagonistic interaction is illustrated by maximum migration rates occurring at intermediate, but low herbivory (< 15%). Assuming herbivory < 20% and favourable conditions for population growth during post-glacial migration, seed dispersal by deer can explain rates of migration achieved in the past, in contrast to previous models of forest herb migration. However, relatively unfavourable conditions for population growth and increasingly intense herbivory by deer may compromise plant migration in the face of present and future climate change. [source] Understanding herb and dietary supplement use in patients with epilepsyEPILEPSIA, Issue 8 2009Kitti Kaiboriboon Summary Objective:, To determine the prevalence of herb and dietary supplement use and to provide a comprehensive analysis of factors influencing the use of these products in patients with epilepsy. Methods:, We performed a cross-sectional study using self-administered questionnaires in a selected group of patients who were receiving care at a tertiary epilepsy center. Logistic regression was used to measure the association between the demographic variables and herb and dietary supplement use. In addition, we performed a MEDLINE search for each of the herb and dietary products used by our patients to determine the effect of these products on seizures and on their potential for interactions with other drugs metabolized by the liver. Results:, One hundred eighty-seven patients completed the survey. Fifty-six percent of this group of patients with epilepsy used herbs and dietary supplements at the time of the survey. A considerable portion (71%) of these patients reported the use of these products to their physician, and most of them relied on their physicians as the primary source of information. Most of the patients used dietary supplement for health promotion rather than to specifically benefit their epilepsy condition. Approximately one-third of patients used herb or dietary supplements that had the potential to increase seizures (16%) or to interact with hepatically metabolized drugs (19%). The most powerful independent predictors of herb and dietary supplement use were partial epilepsy [odds ratio (OR) 3.36; 95% confidence interval (CI) 1.27,8.88] and Caucasian race (OR 3.55; 95% CI 1.11,11.34). Conclusion:, Patients with epilepsy commonly used dietary supplements along with their antiepileptic medications. The majority of these patients used herb and dietary supplements for health promotion rather than because of dissatisfaction with conventional treatment. It is important that physicians involved in the care of patients with epilepsy routinely inquire about the use of dietary supplements and that they make use of reliable resources to assess the safety of these products with regard to modification of seizure risk and the potential for interactions with antiepileptic drugs. [source] Antimelanogenesis effect of Tunisian herb Thymelaea hirsuta extract on B16 murine melanoma cellsEXPERIMENTAL DERMATOLOGY, Issue 12 2007Mitsuko Kawano Abstract:, Skin pigmentation is the result of melanogenesis that occurs in melanocytes and/or melanoma cells. Although melanogenesis is necessary for the prevention of DNA damage and cancer caused by UV irradiation, excessive accumulation of melanin can also cause melanoma. Thus, we focused on the antimelanogenesis effect of an extract from Thymelaea hirsuta, a Tunisian herb. Murine melanoma B16 cells were treated with T. hirsuta extract, and then cell viability and synthesized melanin content were measured. We found that the T. hirsuta extract decreased the synthesized melanin content in B16 cells without cytotoxicity. Tyrosinase is a key enzyme of melanogenesis and extracellular signal-regulated kinase (ERK)-1/2 phosphorylation is known to be related to melanogenesis inhibition. To clarify its mechanism, we also determined ERK1/2 phosphorylation and tyrosinase expression level. ERK1/2 was immediately phosphorylated in cells just after treatment with the extract. The tyrosinase expression was inhibited after 24 h of stimulation with the extract. The T. hirsuta extract was fractionated, and we found that one fraction considerably decreased the melanin synthesis in B16 cells and that this fraction contains daphnanes as the main component. This indicates that our findings might be attributable to daphnanes. [source] Glechoma hederacea (Lamiaceae) in North America: invasion history and current distribution,FEDDES REPERTORIUM, Issue 1-2 2004M. Scholler Glechoma hederacea L. (Ground-ivy, Lamiaceae), a perennial mat-forming herb, is native to the temperate regions of Eurasia and was introduced elsewhere (South East Asia, New Zealand and North America). Based on data obtained from herbaria, literature, online and other data bases and field studies, we documented the invasion history and current distribution of this plant in North America. At present, the plant is recorded from all but two continental states of the USA and all southern provinces of Canada. There are two main ranges: the larger one covers mainly the eastern part of the U.S.A. and a smaller one stretches along the West Coast. While published records of Glechoma hederacea date from 1814, the oldest specimen is from 1829. During the 19th century the species spread westwards at a rate of approximately 30 km/year. The spread and present range of G. hederacea can only be explained by climatic factors (degree of oceanicity) and considering human activity. Especially long distance propagation of vegetative parts of the plants and the change of the environment that accompanies human settlements may have had a major influence on these processes. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Glechoma hederacea L. (Lamiaceae) in Nordamerika: Invasionsgeschichte und derzeitige Verbreitung Glechoma hederacea (Gewöhnlicher Gundermann; Lamiaceae), eine im temperaten Eurasien beheimatete ausdauernde krautige Pflanze konnte sich als Neophyt in Südostasien, Neuseeland und Nordamerika etablieren. Basierend auf Daten aus der Literatur und Datenbanken, Belegdaten aus Herbarien und Felduntersuchungen werden die Ausbreitungsgeschichte der Art in Nordamerika und ihr gegenwärtiges Areal dokumentiert. Gegenwärtig ist die Art aus allen kanadischen Provinzen und mit Ausnahme von zwei Bundesstaaten auch von allen kontinentalen Bundesstaaten der USA dokumentiert. Es gibt zwei Hauptareale: ein großes, welches einen Großteil der östlichen USA einnimmt und ein kleineres an der Westküste. Der älteste Nachweis von 1814 von Glechoma hederacea stammt aus der Literatur, der älteste Beleg von 1829. Im Laufe des 19. Jahrhunderts breitete sich die Art mit einer Geschwindigkeit von etwa 30 km/Jahr nach Westen aus. Ausbreitungsgeschwindigkeit und das gegenwärtige Areal können nur mit Hilfe klimatischer (Ozeanität) und anthropogener Faktoren erklärt werden. Der Mensch trägt vor allem zur Verbreitung vegetativer Pflanzenteile bei und schafft in Siedlungen günstige Wachstumsbedingungen. [source] Composition and antimicrobial activity of the volatile oil of Artemisia kopetdaghensis Krasch., M.Pop.FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2006& Linecz ex Poljak from Iran Abstract Artemisia kopetdaghensis Krasch., M.Pop. & Linecz ex Poljak (Asteraceae) is a common perennial herb growing wild in north-eastern parts of Iran. The essential oil of A. kopetdaghensis was isolated by hydrodistillation in 2.14% (v/w) yield. The chemical composition of the essential oil was examined by GC and GC,MS. Thirty-three compounds were identified, representing 86.8% of the total oil. The major constituents were methyleugenol (24.4%), geranial (13.6%), davanone (11.1%), camphor (9.8%) and neral (7.4%). Minimum inhibitory concentration was determined, using the agar dilution method, against eight bacteria and two fungal strains. The essential oil showed a moderate antimicrobial activity. Copyright © 2006 John Wiley & Sons, Ltd. [source] Variation in essential oil composition of rose-scented geranium (Pelargonium sp.) distilled by different distillation techniques,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Kiran G. D. Babu Abstract The rose-scented geranium (Pelargonium sp.) cultivar ,Kelkar', grown in the agroclimatic conditions of the western Himalayas, was processed by various hydrodistillation methods, which revealed that water distillation of the herb gave a higher oil yield (0.16,0.22%) than the water,steam distillation (0.09,0.12%) and steam distillation methods (0.06,0.18%). The samples were analysed by GC and GC,MS to study and compare the essential oil compositions which revealed that the oil distilled by the water,steam distillation method contained a higher content of monoterpene hydrocarbons (1.7%), followed by steam distillation without cohobation and without recycling (1.5%). A higher content of sesquiterpene hydrocarbons (4.4%) was found in cumulative oil followed by ,direct oil' (4.2%) obtained by steam distillation with cohobation and without recycling of hydrosol, followed by the water,steam distillation method (3.4%). ,Decanted oil', recovered from redistilling the hydrosol obtained by steam distillation with cohobation and without recycling, contained maximum monoterpene cyclic ethers (1.1%) and carbonyl content (9.9%), closely followed by water,steam distillation method (1.1% and 7.2%, respectively). Steam distillation without cohobation and without recycling of hydrosol yielded essential oil with a higher percentage of esters (21.1%), followed by ,direct oil' (16.6%). Lower ester content (5.3%) was noticed in ,decanted oil', followed by oil distilled by steam distillation with cohobation and with recycling (11.8%) and oil distilled in a Clevenger apparatus by the water distillation method (12.2%), whereas maximum total alcohols were found in the ,decanted oil' (75.1%), followed by oil from the Clevenger apparatus (72.8%) and steam distillation with cohobation and with recycling (69.1%). A lower alcohol content was found in the ,direct oil' (55.2%) closely followed by ,cumulative oil' (55.8%). The variation in total alcohol and ester contents in geranium oil samples, distilled by using different processing techniques on pilot scale distillation, is mainly due to hydrolysis of some volatile constituents. This was further supported by acid values of the oils, along with other physicochemical properties, such as speci,c gravity, optical rotation, refractive index, solubility in alcohol, ester value with cold and hot methods, estimation of ester content as geranyl formate and geranyl tiglate, ester number after acetylation, and ester number after formylation with aceto-formic acid and formic acid. Methods have been standardized and proposed for distillations of speci,c quality, e.g. ester-rich and alcohol-rich geranium oils, to meet different requirements of the industry. Copyright © 2004 John Wiley & Sons, Ltd. [source] Chemical composition variability of the essential oil of Conyza canadensis Cronq.FLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2003Anna Lis Abstract The essential oils from different botanical parts (herb, leaves, ,owers, stems, roots) of Conyza canadensis Cronq. were analysed at various ontogenesis phases. R -(+)-limonene and trans - , -bergamotene were the main constituents of the herb, leaf and ,ower oil at all phases of vegetation. The early ,owering phases are the best time for harvesting C. canadensis herb, because the oil yield is the highest (0.7,0.8%) and its chemical composition is constant (limonene 80,81%, trans - , -bergamotene 6,8%). Limonene was the dominating compound of the oils of European origin (French, Italian, Spanish, Belgian, Bulgarian and Lithuanian). Copyright © 2003 John Wiley & Sons, Ltd. [source] Environmentally induced variation in floral traits affects the mating system in Datura wrightiiFUNCTIONAL ECOLOGY, Issue 1 2002E. Elle Summary 1If pollination is unpredictable, selection may favour the production of selfed seeds in the absence of pollen vectors, even in plant species with obvious adaptations for outcrossing. Pollination may be less predictable for plants growing in certain environments if environmental factors affect the floral phenotype. Through effects on flower morphology and the floral display, the environment may affect the outcrossing rate. 2We manipulated two environmental factors, water availability and exposure to insect herbivores, in a common-garden experiment using a perennial herb, Datura wrightii. We measured herkogamy (the separation of anthers and stigmas within flowers), total flower length, and flower number, and used a single-gene trichome dimorphism as a marker to determine per-plant outcrossing rates. 3The large amount of variation in herkogamy was affected by trichome type, irrigation and herbivory. In addition, watered plants had longer corollas, and plants attacked by herbivores had fewer open flowers. Thus environmental factors affect floral phenotype. 4However, irrigation and herbivory did not directly affect outcrossing rate. There were indirect effects of these treatments on outcrossing because plants with increased herkogamy and fewer open flowers had higher outcrossing rates. 5, A greenhouse experiment showed that autonomous selfing is more likely when herkogamy is reduced, and can occur both as the flower opens and when the corolla is shed. 6, These experiments are among the first to show that within-population variation in the mating system can be due to environmentally induced variation in floral traits. [source] Inflorescence characteristics, seed composition, and allometric relationships predicting seed yields in the biomass crop Cynara cardunculusGCB BIOENERGY, Issue 3 2010S. V. ARCHONTOULIS Abstract Cynara (Cynara cardunculus) is a perennial C3 herb that has its potential as bioenergy crop. This paper aims (a) to derive empirical relationships to predict cynara seed yield per head and per unit area, avoiding laborious extraction of seeds from the complex structure of its inflorescences; (b) to determine the head-weight distribution per unit area, the seed composition and the oil profile of cynara seeds; and (c) to estimate the range of cynara biomass, seed and oil yield in representative parts of Greece. We analyzed 16 field experiments, varying in crop age and environmental conditions in Greece. Seed yield per head (SYhead) can be accurately predicted as a linear function of dry head weight (Hw): SYhead=0.429·Hw,2.9 (r2=0.96; n=617). Based on this relationship, we developed a simple two-parameter equation to predict seed yield per unit area (SY): SY=HN·(0.429·,,2.9), where , is the mean head weight (g head,1) and HN is the total number of heads per unit area, respectively. The models were tested against current and published data (n=180 for head-level; n=35 for unit area-level models), and proved to be valid under diverse management and environmental conditions. Attainable cynara seed yields ranged from 190 to 480 g m,2 yr,1, on dry soils and on aquic soils (shallow ground water level). This variation in seed yield was sufficiently explained by the analyses of head-weight distribution per unit area (small, medium and large heads) and variability of seed/head weight ratio at head level. Seed oil concentration (average: 23%) and crude protein concentration (average: 18.7%) were rather invariant across different seed sizes (range: 26,56 mg seed,1) and growing environments. [source] Endemic species and ecosystem sensitivity to climate change in NamibiaGLOBAL CHANGE BIOLOGY, Issue 5 2006WILFRIED THUILLER Abstract We present a first assessment of the potential impacts of anthropogenic climate change on the endemic flora of Namibia, and on its vegetation structure and function, for a projected climate in ,2050 and ,2080. We used both niche-based models (NBM) to evaluate the sensitivity of 159 endemic species to climate change (of an original 1020 plant species modeled) and a dynamic global vegetation model (DGVM) to assess the impacts of climate change on vegetation structure and ecosystem functioning. Endemic species modeled by NBM are moderately sensitive to projected climate change. Fewer than 5% are predicted to experience complete range loss by 2080, although more than 47% of the species are expected to be vulnerable (range reduction >30%) by 2080 if they are assumed unable to migrate. Disaggregation of results by life-form showed distinct patterns. Endemic species of perennial herb, geophyte and tree life-formsare predicted to be negatively impacted in Namibia, whereas annual herb and succulent endemic species remain relatively stable by 2050 and 2080. Endemic annual herb species are even predicted to extend their range north-eastward into the tree and shrub savanna with migration, and tolerance of novel substrates. The current protected area network is predicted to meet its mandate by protecting most of the current endemicity in Namibia into the future. Vegetation simulated by DGVM is projected to experience a reduction in cover, net primary productivity and leaf area index throughout much of the country by 2050, with important implications for the faunal component of Namibia's ecosystems, and the agricultural sector. The plant functional type (PFT) composition of the major biomes may be substantially affected by climate change and rising atmospheric CO2, currently widespread deciduous broad leaved trees and C4 PFTs decline, with the C4 PFT particularly negatively affected by rising atmospheric CO2 impacts by ,2080 and deciduous broad leaved trees more likely directly impacted by drying and warming. The C3 PFT may increase in prominence in the northwestern quadrant of the country by ,2080 as CO2 concentrations increase. These results suggest that substantial changes in species diversity, vegetation structure and ecosystem functioning can be expected in Namibia with anticipated climate change, although endemic plant richness may persist in the topographically diverse central escarpment region. [source] Genetic variation in Sanguisorba minor after 6 years in situ selection under elevated CO2GLOBAL CHANGE BIOLOGY, Issue 8 2004Silvia Wieneke Abstract Genetic variation within plant species in their response to elevated CO2 could be important for long-term changes in plant community composition because it allows for selection of responsive genotypes. Six years of in situ CO2 enrichment in a temperate grassland offered a unique opportunity to investigate such microevolutionary changes in a common herb of that plant community, Sanguisorba minor. Plants were grown from seeds collected at the end of a 6-year treatment in either ambient or elevated CO2. The resulting seedlings were grown under ambient or elevated CO2 and with or without interspecific competition by Bromus erectus in the greenhouse for two seasons. The effect of competition was included because we expected selection under elevated CO2 to favour increased competitive ability. Elevated CO2 in the greenhouse and competition both caused a significant reduction of the total dry mass in S. minor, by 12% and 40%, respectively, with no interaction between CO2 and competition. Genetic variation in all traits was substantial. Seed families responded differently to competition, but the family × greenhouse CO2 interaction was rather weak. There was no main effect of the field CO2 treatment on any parameter analysed in the greenhouse. However, the field CO2 treatment did significantly interact with the greenhouse CO2 treatment for the cumulative number of leaves, suggesting microevolutionary change in this plant trait. Families from ambient field CO2 produced fewer leaves under elevated greenhouse CO2, whereas families from elevated field CO2 retained constant number of leaves in either greenhouse CO2 treatment. Since this resulted in increased litter production of the families from elevated field CO2 under elevated greenhouse CO2, the microevolutionary response should, in turn, affect ecosystem functions through dry matter recycling. [source] Global trends in senesced-leaf nitrogen and phosphorusGLOBAL ECOLOGY, Issue 5 2009Zhiyou Yuan ABSTRACT Aim, Senesced-leaf litter plays an important role in the functioning of terrestrial ecosystems. While green-leaf nutrients have been reported to be affected by climatic factors at the global scale, the global patterns of senesced-leaf nutrients are not well understood. Location, Global. Methods, Here, bringing together a global dataset of senesced-leaf N and P spanning 1253 observations and 638 plant species at 365 sites and of associated mean climatic indices, we describe the world-wide trends in senesced-leaf N and P and their stoichiometric ratios. Results, Concentration of senesced-leaf N was highest in tropical forests, intermediate in boreal, temperate, and mediterranean forests and grasslands, and lowest in tundra, whereas P concentration was highest in grasslands, lowest in tropical forests and intermediate in other ecosystems. Tropical forests had the highest N : P and C : P ratios in senesced leaves. When all data were pooled, N concentration significantly increased, but senesced-leaf P concentration decreased with increasing mean annual temperature (MAT) and mean annual precipitation (MAP). The N : P and C : P ratios also increased with MAT and MAP, but C : N ratios decreased. Plant functional type (PFT), i.e. life-form (grass, herb, shrub or tree), phylogeny (angiosperm versus gymnosperm) and leaf habit (deciduous versus evergreen), affected senesced-leaf N, P, N : P, C : N and C : P with a ranking of senesced-leaf N from high to low: forbs , shrubs , trees > grasses, while the ranking of P was forbs , shrubs , trees < grasses. The climatic trends of senesced-leaf N and P and their stoichiometric ratios were similar between PFTs. Main conclusions, Globally, senesced-leaf N and P concentrations differed among ecosystem types, from tropical forest to tundra. Differences were significantly related to global climate variables such as MAT and MAP and also related to plant functional types. These results at the global scale suggest that nutrient feedback to soil through leaf senescence depends on both the climatic conditions and the plant composition of an ecosystem. [source] | |||||||||||||||||||||||||||||||||||||||||||