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Plants Used (plant + used)
Selected AbstractsPyrrolizidine Alkaloid Containing Plants Used in Mongolian Traditional Medicine: Lappula myosotis Moench.CHEMINFORM, Issue 8 2006Helmut Wiedenfeld Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF. [source] In-vitro Antioxidant and In-vivo Photoprotective Effect of Three Lyophilized Extracts of Sedum telephium L. LeavesJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2000FRANCESCO BONINA Sedum telephium L. is a medicinal plant used in antiquity to cure many types of inflammatory skin diseases. The leaves (without the external cuticle), are used to promote healing and reduce skin inflammation and pain, and contain various components. We found two major components: flavonol glycosides and polysaccharides, with molecular weight between 13 000 and 13 500 Da. We evaluated the in-vitro antioxidant and in-vivo skin photoprotective effects of three lyophilized extracts obtained from the juice of S. telephium L. leaves: a total lyophilized juice, a lyophilized flavonolic fraction, and a lyophilized polysaccharidic fraction. Two in-vitro models were used: the bleaching of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical, and the protective effect against UV-induced peroxidation on phosphatidylcholine multilamellar vesicles, as model membranes. The antioxidant/radical scavenging activity of each lyophilized extract was also assessed in-vivo by determining their ability to reduce UVB-induced skin erythema (monitored by reflectance spectrophotometry) in healthy human volunteers. The findings of the in-vitro experiments clearly demonstrated that, unlike the lyophilized polysaccharidic fraction, the lyophilized flavonolic fraction and total lyophilized juice possess strong antioxidant/free radical scavenging properties, which are likely due to phenolic compounds. Consistent with these findings, gel formulations of both the total lyophilized juice and, to a greater degree, the lyophilized flavonolic fraction appeared to possess a strong protective effect against UV-induced skin erythema in-vivo, whereas the lyophilized polysaccharidic fraction was completely ineffective. The in-vitro and in-vivo results suggest that, both the total lyophilized juice and, in particular, the lyophilized flavonolic fraction, but not the lyophilized polysaccharidic fraction of S. telephium L. leaves, have photoprotective effects against UVB-induced skin damage. [source] Azorellane diterpenoids from Laretia acaulis inhibit nuclear factor-kappa B activityPHYTOTHERAPY RESEARCH, Issue 11 2007Jorge Borquez Abstract Transcription factor NF- ,B plays a key role in the inducible expression of genes mediating proinflammatory effects, and is thus an important target for the development of antiinflammatory drugs. Laretia acaulis (Cav.) Gill et Hook (Apiaceae) is a medicinal plant used in the high Andes mountains for different ailments such as diabetes, inflammation and for general pain. In addition to the known azorellanol (2) and 7-deacetylazorellanol (4), 13-epiazorellanol (1) was also isolated from the aerial part of this plant. Its structure was based on spectroscopic comparison with azorellanol (2) and by chemical characterization. While compounds 2 and 4 showed potent anti-NF- ,B activity by targeting the activity of the I,B, kinase, compound 1 was completely inactive highlighting the importance of position 13 in the biological activities of this class of tetracyclic diterpenoids. Copyright © 2007 John Wiley & Sons, Ltd. [source] Additional antiprotozoal constituents from Cuphea pinetorum, a plant used in Mayan traditional medicine to treat diarrhoeaPHYTOTHERAPY RESEARCH, Issue 8 2005Fernando Calzada Abstract In addition to kaempferol and quercetin already found in the roots from Cuphea pinetorum, bioassay-guided fractionation of the crude extract of the aerial part of this species gave four flavonoid glycosides, quercetin-3- O - , -rhamnopyranoside, luteolin-7- O - , - d -glucopyranoside, apigenin-7- O - , - l -rhamnopyranoside and apigenin-7- O - , - d -glucopyranoside, as well as squalen and , -sitosterol. In vitro antiamoebic and antigiardial activities of isolated compounds indicated that kaempferol is the principal antiprotozoal agent in C. pinetorum. Based on finding this antiprotozoal inhibitor, flavonoids were studied in order to elucidate structure-activity relationships. These data suggest that kaempferol may play an important role in antidiarrhoeal activity of C. pinetorum. Copyright © 2005 John Wiley & Sons, Ltd. [source] Phytochemistry and preliminary biological evaluation of Cyathostemma argenteum, a malaysian plant used traditionally for the treatment of breast cancerPHYTOTHERAPY RESEARCH, Issue 7 2004i Khamis Abstract Bioassay guided fractionation of the roots of Cyathostemma argenteum using the brine shrimp resulted in the isolation of two uncommon ,avanones, 2,5-dihydroxy-7-methoxy,avanone 1 and 2,5-dihydroxy-6,7-dimethoxy,avanone 2 while the stem bark yielded the related compounds 5-hydroxy-7-methoxy,avone 3 and 5-hydroxy-6,7-dimethoxy,avone 4. The alkaloids liriodenine 5 and discretamine 6 as well as benzyl benzoate 7 were isolated from the roots and 6 was also isolated from the stembark. In cytotoxicity tests using four human breast cancer cell lines, 1 and 2 were weakly toxic to MCF-7 cells (IC50 = 19.6 and 19.0 µm, respectively) but showed little activity against MCF-7 cells resistant to doxorubicin or against two oestrogen receptor-de,cient cell lines. Compound 5, but not 6 and 7, was moderately cytotoxic against all four cell lines. These results are discussed in the context of the traditional use of C. argenteum in the treatment of breast cancer. Copyright © 2004 John Wiley & Sons, Ltd. [source] Antioxidant properties of extracts from Alchornea laxiflora (Benth) Pax and HoffmanPHYTOTHERAPY RESEARCH, Issue 7 2003E. Olatunde Farombi Abstract The antioxidant activities of the leaf and root extracts of Alchornea laxiflora, a plant used locally for the preservation of food items in Nigeria, were evaluated using the ferric thiocyanate method, horseradish peroxidase catalysed oxidation of 2,2 azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), , -carotene linoleate model system and Fe2+/ascorbate/H2O2 -induced rat liver microsomal lipid peroxidation. The crude hexane root (HR), methanol root (MR), methanol leaf (ML) and hexane leaf (HL) extracts from A. laxiflora were tested for antioxidant activities. Antioxidant activity decreased in the following order: HR (76.4%), MR (63%), ML (40%) and HL (38%) at a concentration of 0.05% v/v. The antioxidant activity of HR compared to that of butylated hydroxyanisole (BHA) (80%), a standard antioxidant. The total antioxidant activity (TAA) of the crude extracts suggests that activity is highest in the HR compared with the others. The TAA value was estimated to be 8.0 measured as mm of vitamin C equivalent. Six column chromatographic fractions (FI,FVI) from HR showed antioxidant activity to varying extents in the , -carotene model system in the order of FII > FI > FVI > FIII > FIV > FV. FII exhibited the highest antioxidant activity in all model systems utilized, it recorded a higher antioxidant activity than BHA and quercetin in the , -carotene linoleate and Fe2+/ascorbate/H2O2. TLC analysis of fraction II revealed the presence of terpenoid compounds (radiant green coloration with 2,4 dinitrophenylhydrazine). Our results suggest that A. laxiflora contains potent natural antioxidants and may therefore be relevant in the preservation of lipid food products, which are prone to oxidation and rancidity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Osteobiographic analysis of skeleton I, Sítio Toca dos Coqueiros, Serra da Capivara National Park, Brazil, 11,060 BP: First resultsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2002Andrea Lessa Abstract This paper presents an osteobiographic analysis of a single skeleton found in a small rock shelter known as Toca dos Coqueiros, Piauí, Brazil. This find is of interest because of an exceptionally old radiocarbon date associated with it. The date (11,060 BP) was obtained from charcoal associated directly with the skeleton. This is an interesting find because of the rarity of osteobiographic studies of skeletons of such antiquity. Despite the existence of two projectile points in association with the burial, the morphological and molecular analyses of the skeleton demonstrated that this was a female. She was about 35,45 years of age at death. The skeleton exhibited acute and chronic bone lesions. Oral pathology was also observed, including an interproximal dental groove, probably caused by the therapeutic use of a cactus thorn. This could be one of the oldest cases of an analgesic plant used in the prehistoric Americas. Am J Phys Anthropol 118:99,110, 2002. © 2002 Wiley-Liss, Inc. [source] The effect of Phyllanthus niruri on urinary inhibitors of calcium oxalate crystallization and other factors associated with renal stone formationBJU INTERNATIONAL, Issue 9 2002A.M. Freitas Objective,To evaluate the effect of an aqueous extract of Phyllanthus niruri (Pn), a plant used in folk medicine to treat lithiasis, on the urinary excretion of endogenous inhibitors of lithogenesis, citrate, magnesium and glycosaminoglycans (GAGs). Materials and methods,The effect of chronic (42 days) administration of Pn (1.25 mg/mL/day, orally) was evaluated in a rat model of urolithiasis induced by the introduction of a calcium oxalate (CaOx) seed into the bladder of adult male Wistar rats. The animals were divided into four groups: a sham control (16 rats); a control+Pn (six); CaOx+water instead of Pn (14); and CaOx+Pn (22). Plasma and urine were collected after 42 days of treatment for biochemical analysis and the determination of urinary excretion of citrate, magnesium and GAGs. The animals were then killed and the calculi analysed. Results,The creatinine clearance or urinary and plasma concentrations of Na+, K+, Ca2+, oxalate, phosphate and uric acid were unaffected by Pn or the induction of lithiasis. Treatment with Pn strongly inhibited the growth of the matrix calculus and reduced the number of stone satellites compared with the group receiving water. The calculi were eliminated or dissolved in some treated animals (three of 22). The urinary excretion of citrate and magnesium was unaffected by Pn treatment. However, the mean (sd) urinary concentration of GAGs was significantly lower in rats treated with CaOx+Pn, at 5.64 (0.86) mg/g creatinine, than when treated with CaOx + water, at 11.78 (2.21) mg/g creatinine. In contrast, the content of GAGs in the calculi was higher in the CaOx + Pn rats, at 48.0 (10.4) g/g calculus, than in the CaOx + water group, at 16.6 (9.6) g/g calculus. Conclusion,These results show that Pn has an inhibitory effect on crystal growth, which is independent of changes in the urinary excretion of citrate and Mg, but might be related to the higher incorporation of GAGs into the calculi. [source] Plant preference in relation to life history traits in the zoophytophagous predator Dicyphus hesperusENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2004Juan Antonio Sanchez Abstract Dicyphus hesperus Knight (Heteroptera: Miridae) is an omnivorous predator used to control pests of greenhouse vegetables. Plant preferences and life history traits were studied using nine plant species: Lycopersicon esculentum Mill. (Solanaceae), Capsicum annuum L. (Solanaceae), Verbascum thapsus L. (Scrophulariaceae), Nepeta cataria L. (Lamiaceae), Stachys albotomentosa (Lamiaceae), Nicotiana tabacum L. (Solanaceae), Vicia sativa L. (Fabaceae), Zea mays L. (Gramineae), and Chrysanthemum coronarium L. (Asteraceae). Plants were selected from among potential target crops, natural hosts, plants used for mass rearing, and plants on which D. hesperus has not been reported. Plant preference was measured by multi-choice host plant selection and oviposition assays. Development and reproduction were measured on each of the plant species on both a plant diet alone and on a plant diet supplemented with Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs. Dicyphus hesperus females and nymphs expressed a preference for some plants over others. Plant preference ranged from low preference plants, such as Z. mays, V. sativa, C. coronarium, and C. annuum, to high preference plants such as V. thapsus, N. tabacum, and S. albotomentosa. When E. kuehniella eggs were supplied, there were few differences in the development time and fecundity of D. hesperus among plants, with the exception of corn and broad bean, where fecundity was lower. On a plant diet alone, nymphs were able to complete their development on V. thapsus, C. annuum, and N. cataria. However, mortality and development time were much lower on V. thapsus than on C. annuum and N. cataria. On most of the plant species D. hesperus did not lay any eggs when fed on a plant diet alone. On V. thapsus, females laid a few eggs and lived longer than when fed on prey. Dicyphus hesperus females tended to prefer host plants on which nymph survival without prey was greatest. [source] Antibacterial activity of plant extracts from northwestern ArgentinaJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007J.R. Soberón Abstract Aims:, To determine the antibacterial and cytotoxic activities of aqueous and ethanolic extracts of northwestern Argentinian plants used in folk medicine. To compare the mentioned activities with those of five commercial antibiotics. To identify the compounds responsible for the antibacterial activity. Methods and Results:, Plant extracts were prepared according to traditional uses in northwestern Argentina. Antibacterial activity was assayed by agar dilution in Petri dishes and broth dilution in 96-well plates. Lethal dose 50 (LD50) was determined by the Artemia salina assay. Phytochemical analysis was performed by sample adsorption on silica gel, thin-layer chromatography (TLC), bioautography and UV-visible spectra. The results showed that Tripodanthus acutifolius aqueous extracts have lower minimal inhibitory concentrations (MIC) (502 and 506 ,g of extracted material (EM) per ml for infusion and decoction, respectively) than cefotaxim MIC (640 ,g ml,1) against Acinetobacterfreundii (303). These data were lower than their LD50. Tripodanthus acutifolius tincture showed lower MIC (110 ,g of EM per ml) and minimal bactericidal concentration (MBC) (220 ,g of EM per ml) than cefotaxim (MIC and MBC of 320 ,g ml,1) for Pseudomonasaeruginosa. This extract also showed a MIC/MBC of 110/220 ,g of EM per ml, lower than oxacillin (MIC/MBC of 160/220 ,g ml,1) for Staphylococcus aureus (ATCC 25923). The cytotoxicity of all extracts were compared with that of commercial antibiotics. Rutin (3,3,,4,,5,7-pentahydroxyflavone 3- , -rhamnosilglucoside), iso -quercitrin (3,3,,4,,5,7-pentahydroxyflavone 3- , -glucoside) and a terpene would be partially responsible for the antibacterial activity of T. acutifolius infusion. Conclusions:,Tripodanthus acutifolius extracts had the ability to inhibit bacterial growth. The antibacterial activity differs with the applied extractive method, and it could be partially attributed to glycoflavonoids. This paper contributes to the knowledge of antibacterial capacity of plants from northwestern Argentina. Significance and Impact of the Study:, These antibacterial activities support further studies to discover new chemical structures that can contribute to alleviate or cure some illnesses. [source] Antimalarial compounds isolated from plants used in traditional medicineJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2009Joanne Bero Abstract Objectives This review covers the compounds with antiplasmodial activity isolated from plants published from 2005 to the end of 2008, organized according to their phytochemical classes. Details are given for substances with IC50 values , 11 ,M. Key findings Malaria is a major parasitic disease in many tropical and subtropical regions and is responsible for more than 1 million deaths each year in Africa. The rapid spread of resistance encourages the search for new active compounds. Nature and particularly plants used in traditional medicine are a potential source of new antimalarial drugs as they contain molecules with a great variety of structures and pharmacological activities. Summary A large number of antimalarial compounds with a wide variety of structures have been isolated from plants and can play a role in the development of new antimalarial drugs. Ethnopharmacological approaches appear to be a promising way to find plant metabolites that could be used as templates for designing new derivatives with improved properties. [source] Activity against drug resistant-tuberculosis strains of plants used in Mexican traditional medicine to treat tuberculosis and other respiratory diseasesPHYTOTHERAPY RESEARCH, Issue 1 2008María del Rayo Camacho-Corona Abstract Tuberculosis (TB) kills about 3 million people per year worldwide. Furthermore, TB is an infectious disease associated with HIV patients, and there is a rise in multidrug-resistant TB (MDR-TB) cases around the world. There is a need for new anti-TB agents. The study evaluated the antimycobacterial activity of nine plants used in Mexican traditional medicine to treat tuberculosis and other respiratory diseases. Nasturtium officinale showed the best activity (MIC = 100 µg/mL) against the sensitive Mycobacterium tuberculosis. The following plants were active also but at 200 µg/mL: Citrus sinensis, Citrus aurantifolia, Foeniculum vulgare, Larrea tridentata, Musa acuminata and Olea europaea. Contrary to the above data, activity against drug-resistant variants of M. tuberculosis was more evident, e.g. N. officinale was the most potent (MIC , 100 µg/mL) against the four mono-resistant variants tested; F. vulgare and O. europaea were active against all the resistant variants (MICs , 100 µg/mL). The most susceptible variant was the isoniazid resistant, being inhibited by C. aurantifolia, C. sinensis and O. europaea (MIC = 25 µg/mL). These data point to the importance of biological testing of extracts against drug-resistant M. tuberculosis isolates, and the bioguided assay of these extracts for the identification of lead compounds against MDR-TB isolates. Copyright © 2007 John Wiley & Sons, Ltd. [source] In vitro Leishmanicidal activity of naturally occurring chalconesPHYTOTHERAPY RESEARCH, Issue 2 2001Oliver Kayser Abstract A variety of chalcones have been shown to exhibit activity against Leishmania parasites. In contrast to synthetic or semisynthetic chalcones, only a few plant-derived compounds have been investigated. To provide a scientific rational for the antiprotozoal potency of plants used in ethnomedicine and containing chalcones, and in the search for new antiprotozoal drugs, we have carried out a primary screening for in vitro leishmanicidal activity of 20 chalcones isolated from plants. The compounds were tested against extracellular promastigotes of Leishmania donovani, L. infantum, L. enrietii and L. major, and against intracellular amastigote L. donovani residing within murine macrophages. Against the extracellular Leishmania (L. donovani), most compounds were active with EC50 values between 0.07 and 2.01,µg/mL. Some of these chalcones, 2,,4,-dihydroxy-4-methoxychalcone, 2,-hydroxy-3,4-dimethoxychalcone and 2-hydroxy-4,4,-dimethoxychalcone also significantly inhibited the intracellular survival of L. donovani parasites with EC50 values between 0.39 and 0.41,µg/mL. When tested against murine bone marrow-derived macrophages as a mammalian host cell control, all compounds with antileishmanial activities also proved to be cytotoxic to varying extents (EC50 0.19,2.06,µg/mL). Correlations between molecular structures and antileishmanial activity are discussed in detail. Specific compounds are illustrated with emphasis on their mode of action and potential for the development of selective antiprotozoal agents. Copyright © 2001 John Wiley & Sons, Ltd. [source] Density-Induced Plant Size Reduction and Size Inequalities in Ethylene-Sensing and Ethylene-Insensitive TobaccoPLANT BIOLOGY, Issue 2 2004R. Pierik Abstract: Plant competition for light is a commonly occurring phenomenon in natural and agricultural vegetations. It is typically size-asymmetric, meaning that slightly larger individuals receive a disproportionate share of the light, leaving a limited amount of light for the initially smaller individuals. As a result, size inequalities of such stands increase with competition intensity. A plant's ability to respond morphologically to the presence of neighbour plants with enhanced shoot elongation, the so-called shade avoidance response, acts against the development of size inequalities. This has been shown experimentally with transgenic plants that cannot sense neighbours and, therefore, show no shade avoidance responses. Stands of such transgenic plants showed a much stronger development of size inequalities at high plant densities than did wild type (WT) stands. However, the transgenic plants used in these experiments displayed severely hampered growth rates and virtually no response to neighbours. In order to more precisely study the impact of this phenotypic plasticity on size inequality development, experiments required plants that have normal growth rates and reduced, but not absent, shade avoidance responses. We made use of an ethylene-insensitive, transgenic tobacco genotype (Tetr) that has wild type growth rates and moderately reduced shade avoidance responses to neighbours. Here, we show that the development of size inequalities in monocultures of these plants is not affected unambiguously different from wild type monocultures. Plots of Tetr plants developed higher inequalities for stem length than did WT, but monocultures of the two genotypes had identical CV (Coefficient of Variance) values for shoot biomass that increased with plant density. Therefore, even though reduced shade avoidance capacities led to the expected higher size inequalities for stem length, this does not necessarily lead to increased size inequalities for shoot biomass. [source] Metallomics and chemical speciation: towards a better understanding of metal-induced stress in plantsANNALS OF APPLIED BIOLOGY, Issue 3 2009M.A.Z. Arruda Abstract Most metal ions are toxic to plants, even at low concentrations, despite the fact that some are essential for growth and play key roles in metabolism. The majority of metals induce the formation of reactive oxygen species, which require the synthesis of additional antoxidant compounds and enzymes for their removal. New techniques that have greatly improved the identification, localisation and quantification of metals within plant tissues have led to the science of metallomics. This advancement in knowledge should eventually allow the characterisation of plants used in the process of phytoremediation of soils contaminated with toxic metals. [source] Short-term clinical effects of commercially available gel containing Acacia arabica: a randomized controlled clinical trialAUSTRALIAN DENTAL JOURNAL, Issue 1 2010AR Pradeep Abstract Background:, Certain plants used in folk medicine serve as a source of therapeutic agent by having antimicrobial and other multi-potential effects. This prospective, randomized, placebo and positively controlled clinical trial was designed to evaluate the short-term clinical effects of a commercially available gel containing Acacia arabica in the reduction of plaque and gingival inflammation in subjects with gingivitis. Methods:, Ninety subjects diagnosed with chronic generalized gingivitis were selected and randomly divided into three groups: Group I , placebo gel, Group II , gumtone gel and Group III , 1% chlorhexidine gel. Clinical evaluation was undertaken using the gingival index of Loe and Silness and the plaque index at baseline, 2 weeks, 4 weeks and 6 weeks. A subjective evaluation was undertaken by questionnaire. Results:, Gumtone gel showed significant clinical improvement in gingival and plaque index scores as compared to a placebo gel. This improvement was comparable to 1% chlorhexidine gel. Unlike chlorhexidine gel, gumtone gel was not associated with any discolouration of teeth or unpleasant taste. Conclusions:, Gumtone gel may be a useful herbal formulation for chemical plaque control agent and improvement in plaque and gingival status. [source] Gußasphalt-Dichtsysteme in Anlagen zum Lagern, Abfüllen und Umschlagen wassergefährdender Stoffe , Neue allgemeine bauaufsichtliche ZulassungenBAUTECHNIK, Issue 8 2004Ullrich Kluge Dipl.-Ing. Anlagen, Anlagenteile und technische Schutzvorkehrungen für Anlagen zum Umgang mit wassergefährdenden Stoffen müssen Anforderungen aus verschiedenen Rechtsbereichen wie z. B. Wasserrecht, Baurecht, Arbeitsschutzrecht usw. erfüllen. Das Deutsche Institut für Bautechnik (DIBt) erteilt allgemeine bauaufsichtliche Zulassungen für Abdichtungsmittel zur Verwendung in Dichtkonstruktionen in Anlagen zum Lagern, Abfüllen und Umschlagen wassergefährdender Stoffe (LAU-Anlagen). Die Anforderungen an die Materialien und die Prüfverfahren für deren Nachweis sind in den Zulassungsgrundsätzen bzw. Prüfprogrammen des DIBt niedergelegt. Durch das DIBt wurden neue allgemeine bauaufsichtliche Zulassungen für Gußasphalt-Dichtsysteme in LAU-Anlagen erteilt. Flouting asphalt in sealing systems for plants used for the containment, handling and filling substances hazardous to water, new technical approvals. Sealing systems in plants, parts of them and technical protection devises for the dealing with substances hazardous to water have to satisfy certain requirements as laid down in the different fiends of national public law, for example law relating to water, building regulations, law on protection of work, etc. The Deutsche Institut für Bautechnik (DIBt) granted technical approvals in the field of sealing systems for plants used for the containment, handling and filling substances hazardous to water. The requirements of materials and for the tests for their properties of them are laid down in the principles or test programs for technical approvals by DIBt. The Deutsche Institut für Bautechnik (DIBt) granted new technical approvals for sealing systems made of flouting asphalt for plants used for the containment, handling and filling substances hazardous to water. [source] The evolution of sex pheromones in an ecologically diverse genus of fliesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2009MATTHEW R. E. SYMONDS In theory, pheromones important in specific mate recognition should evolve via large shifts in composition (saltational changes) at speciation events. However, where other mechanisms exist to ensure reproductive isolation, no such selection for rapid divergence is expected. In Bactrocera fruit flies (Diptera: Tephritidae), males produce volatile chemicals to attract females for mating. Bactrocera species exhibit great ecological diversity, with a wide range of geographical locations and host plants used. They also have other mechanisms, including temporal and behavioural differences, which ensure reproductive isolation. Therefore, we predicted that their sex pheromones would not exhibit rapid divergence at speciation events. In the present study, we tested this idea by combining data on male sex pheromone composition for 19 species of Bactrocera with a phylogeny constructed from DNA sequence data. Analyses of the combined data revealed positive correlations between pheromone differences and nucleotide divergence between species, and between the number of pheromone changes along the phylogeny and the branch lengths associated with these changes. These results suggest a gradual rather than saltational mode of evolution. However, remarkable differences in sex pheromones composition exist, even between closely-related species. It appears therefore that the mode of evolution of sex pheromones in Bactrocera is best described by rapid saltational changes associated with speciation, followed by gradual divergence thereafter. Furthermore, species that do not overlap ecologically are just as different pheromonally as species that do. Thus, large changes in pheromone composition appear to be achieved, even in cases where other mechanisms to ensure reproductive isolation exist. We suggest that these differences are closely associated with rapid changes in host plant use, which is a characteristic feature of Bactrocera speciation. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 594,603. [source] A high throughput drug screen based on fluorescence resonance energy transfer (FRET) for anticancer activity of compounds from herbal medicineBRITISH JOURNAL OF PHARMACOLOGY, Issue 3 2007H Tian Background and purpose: We report the development of a very efficient cell-based high throughput screening (HTS) method, which utilizes a novel bio-sensor that selectively detects apoptosis based on the fluorescence resonance energy transfer (FRET) technique. Experimental approach: We generated a stable HeLa cell line expressing a FRET-based bio-sensor protein. When cells undergo apoptosis, they activate a protease called ,caspase-3'. Activation of this enzyme will cleave our sensor protein and cause its fluorescence emission to shift from a wavelength of 535 nm (green) to 486 nm (blue). A decrease in the green/blue emission ratio thus gives a direct indication of apoptosis. The sensor cells are grown in 96-well plates. After addition of different chemical compounds to each well, a fluorescence profile can be measured at various time-points using a fluorescent plate reader. Compounds that can trigger apoptosis are potential candidates as anti-cancer drugs. Key results: This novel cell-based HTS method is highly effective in identifying anti-cancer compounds. It was very sensitive in detecting apoptosis induced by various known anti-cancer drugs. Further, this system detects apoptosis, but not necrosis, and is thus more useful than the conventional cell viability assays, such as those using MTT. Finally, we used this system to screen compounds, isolated from two plants used in Chinese medicine, and identified several effective compounds for inducing apoptosis. Conclusions and Implications: This FRET-based HTS method is a powerful tool for identifying anti-cancer compounds and can serve as a highly efficient platform for drug discovery. British Journal of Pharmacology (2007) 150, 321,334. doi:10.1038/sj.bjp.0706988 [source] | ||||||||||||||||