3,239 research outputs found

    Flowers in Australia: phytochemical studies on the Illawarra flame tree and Alstonville

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    The first reported phytochemical studies on two species of flowers in Australia enabled the identification of six secondary metabolites from Illawarra flame tree flower (Brachychiton acerifolius) and seven secondary metabolites from the flowers of the Alstonville (Tibouchina lepidota). Pelargonidin 3-(6-coumarylglucoside)-5-(6-acetylglucoside) was found to be responsible for the red colour of B. acerifolius, whereas malvidin 3-(coumarylglucoside)-5-(acetylxyloside) was responsible for the purple colour of (T. lepidota) flowers. (2S)-4,5-Dihydroxyflavanone 7-O-β-d-glucuronide methyl ester was isolated for the first time from B. acerifolius, and its absolute configuration was determined by circular dichroism spectroscopy. Some of the traditional uses of B. acerifolius could also be correlated with the known activity of the isolated metabolites

    Revealing indigenous Indonesian traditional medicine: anti-infective agents

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    Indonesia is rich in medicinal plants which the population has used traditionally from generation to generation for curing diseases. Our interest in the treatment of infectious diseases has lead to the investigation of traditional Indonesian treatments. In this review, we present a comprehensive review of ethnopharmacologically directed screening in Indonesian medicinal plants to search for new anti-viral, antimalarial, anti-bacterial and anti-fungal agents. Some potent drug leads have been isolated from Indonesian medicinal plants. Further research is still required for the lead development as well as the search for new bioactive compounds from the enormous medicinal plant resources

    Vascular epiphytic medicinal plants as sources of therapeutic agents: their ethnopharmacological uses, chemical composition, and biological activities

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    This is an extensive review on epiphytic plants that have been used traditionally as medicines. It provides information on 185 epiphytes and their traditional medicinal uses, regions where Indigenous people use the plants, parts of the plants used as medicines and their preparation, and their reported phytochemical properties and pharmacological properties aligned with their traditional uses. These epiphytic medicinal plants are able to produce a range of secondary metabolites, including alkaloids, and a total of 842 phytochemicals have been identified to date. As many as 71 epiphytic medicinal plants were studied for their biological activities, showing promising pharmacological activities, including as anti-inflammatory, antimicrobial, and anticancer agents. There are several species that were not investigated for their activities and are worthy of exploration. These epipythes have the potential to furnish drug lead compounds, especially for treating cancers, and thus warrant indepth investigations

    Forum: The eusociality continuum

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    Eusocial societies are traditionally characterized by a reproductive division of labor, an overlap of generations, and cooperative care of the breeders' young. Eusociality was once thought to occur only in termites, ants, and some bee and wasp species, but striking evolutionary convergences have recently become apparent between the societies of these insects and those of cooperatively breeding birds and mammals. These parallels have blurred distinctions between cooperative breeding and eusociality, leading to calls for either drastically restricting or expanding usage of these terms. We favor the latter approach. Cooperative breeding and eusociality are not discrete phenomena, but rather form a continuum of fundamentally similar social systems whose main differences lie in the distribution of lifetime reproductive success among group members. Therefore we propose to array vertebrate and invertebrate cooperative breeders along a common axis, representing a standardized measure of reproductive variance, and to drop such (loaded) terms as "primitive” and "advanced” eusociality. The terminology we propose unites all occurrences of alloparental helping of kin under a single theoretical umbrella (e.g., Hamilton's rule). Thus, cooperatively breeding vertebrates can be regarded as eusocial, just as eusocial invertebrates are cooperative breeders. We believe this integrated approach will foster potentially revealing cross-taxon comparisons, which are essential to understanding social evolution in birds, mammals, and insect

    Anti-infective and anti-cancer properties of the Annona species: their ethnomedicinal uses, alkaloid diversity, and pharmacological activities

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    Annona species have been a valuable source of anti-infective and anticancer agents. However, only limited evaluations of their alkaloids have been carried out. This review collates and evaluates the biological data from extracts and purified isolates for their anti-infective and anti-cancer activities. An isoquinoline backbone is a major structural alkaloid moiety of the Annona genus, and more than 83 alkaloids have been isolated from this genus alone. Crude extracts of Annona genus are reported with moderate activities against Plasmodium falciparum showing larvicidal activities. However, no pure compounds from the Annona genus were tested against the parasite. The methanol extract of Annona muricata showed apparent antimicrobial activities. The isolated alkaloids from this genus including liriodenine, anonaine, asimilobine showed sensitivity against Staphylococcus epidermidis. Other alkaloids such as (+)-Xylopine and isocoreximine indicated significant anti-cancer activity against A549 and K-562 cell lines, respectively. This review revealed that the alkaloids from Annona genus are rich in structural diversity and pharmacological activities. Further exploration of this genus and their alkaloids has potential for developing novel anti-infective and anticancer drugs

    Fullerene van der waals Oligomers as electron traps

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    Density functional theory calculations indicate that van der Waals fullerene dimers and larger oligomers can form interstitial electron traps in which the electrons are even more strongly bound than in isolated fullerene radical anions. The fullerenes behave like super atoms , and the interstitial electron traps represent one-electron intermolecular σ-bonds. Spectroelectrochemical measurements on a bis-fullerene-substituted peptide provide experimental support. The proposed deep electron traps are relevant for all organic electronics applications in which non-covalently linked fullerenes in van der Waals contact with one another serve as n-type semiconductors

    HPV Vaccine Coverage Among Adolescent Males in Ohio: Results of a Longitudinal Study

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    Background: Human papillomavirus (HPV) vaccine has been recommended for males in the United States since 2011, yet little is known about vaccine coverage among adolescent males in Ohio. Our longitudinal study examined HPV vaccine coverage among adolescent males in Ohio and identified predictors of vaccination.Methods: The Buckeye Teen Health Study recruited adolescent males aged 11 to 16 years and their parents from 1 urban county and 9 rural counties in Ohio. We report longitudinal vaccination data on 1126 adolescent males, with baseline data from 2015-2016 and follow-up data from 2017-2018. We used multivariable Poisson regression to identify predictors of HPV vaccine initiation that occurred between baseline and follow-up.Results: At baseline, 42.4% of parents reported their sons had initiated the HPV vaccine series. Among parents whose sons were unvaccinated at baseline, 36.3% indicated initiation at follow-up. Initiation at follow-up was more com-mon among sons who had received influenza vaccine (RR = 1.54, 95% CI = 1.08-2.18) or whose parents indicated lack of a recent visit to a doctor as the main reason for not yet vaccinating at baseline (RR = 1.41, 95% CI = 1.02-1.95). Initiation was less common among sons whose parents had an associate degree or some college education (RR = 0.28, 95% CI = 0.46-0.99). Main reasons for not vaccinating changed from baseline to follow-up among parents of unvaccinated sons.Conclusion: Although HPV vaccine initiation increased over time, many adolescent males in Ohio remain unvac-cinated. Findings can help guide future strategies for increasing HPV vaccine coverage among this population

    A convenient and efficient synthesis of (S)-lysine and (S)-arginine homologues via olefin cross-metathesis

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    A convenient five step synthesis of (S)-homolysine, incorporating a key olefin cross-metathesis step in the chain extension methodology, has been developed, together with a six step related synthesis of a new homologue of arginine, (S)-bishomoarginine

    SkyMapper Filter Set: Design and Fabrication of Large Scale Optical Filters

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    The SkyMapper Southern Sky Survey will be conducted from Siding Spring Observatory with u, v, g, r, i and z filters that comprise glued glass combination filters of dimension 309x309x15 mm. In this paper we discuss the rationale for our bandpasses and physical characteristics of the filter set. The u, v, g and z filters are entirely glass filters which provide highly uniform band passes across the complete filter aperture. The i filter uses glass with a short-wave pass coating, and the r filter is a complete dielectric filter. We describe the process by which the filters were constructed, including the processes used to obtain uniform dielectric coatings and optimized narrow band anti-reflection coatings, as well as the technique of gluing the large glass pieces together after coating using UV transparent epoxy cement. The measured passbands including extinction and CCD QE are presented.Comment: 9 pages, 2 tables, 7 figure

    Experimental realization of a nonlinear acoustic lens with a tunable focus

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    We realize a nonlinear acoustic lens composed of a two-dimensional array of sphere chains interfaced with water. The chains are able to support solitary waves which, when interfaced with a linear medium, transmit compact pulses with minimal oscillations. When focused, the lens is able to produce compact pressure pulses of high amplitude, the “sound bullets.” We demonstrate that the focal point can be controlled via pre-compression of the individual chains, as this changes the wave speed within them. The experimental results agree well both spatially and temporally with analytical predictions over a range of focus locations
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