Search

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pesquisa Veterinaria Brasileira is the property of Colegio Brasileiro de Patologia Animal - CBPA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Echiteae (Apocynaceae) comprises about 200 species divided among 19 genera, 16 of which are restricted to the Neotropics, the other 3 to the Paleotropics. There are two large genera, Prestonia and Parsonsia, in the Neotropics and Paleotropics, respectively, whereas three-fourths of the genera contain only one to four species. In this study DNA of 82 species was extracted and amplified for four molecular markers: three plastid (trnL intron + trnL-trnF intergenic spacer, rpl16 intron, matK + 5'/ 3' trnK intron) and the nuclear ribosomal region ITS. The ingroup comprised 70 species from 17 genera in the tribe, and included representatives of all subtribes; the outgroup included 5 species each from the two putatively most closely related tribes, Odontadenieae and Mesechiteae, as well as 2 rooting species. Phylogenetic analyses were conducted using Bayesian inference and maximum likelihood approaches. Echiteae and four of its subtribes (Echitinae, Parsonsiinae, Peltastinae, Prestoniinae) as currently circumscribed were shown to be non-monophyletic. The fifth subtribe, Pentalinoninae, though monophyletic, does not belong to Echiteae; it was resolved as sister to a clade of Odontadenieae, where it fits better, since in both the characteristic secondary compounds are cardenolides. Prestonia and Temnadenia were resolved as polyphyletic, with P. riedelii grouped with Rhodocalyx and T. ornata nested within Prestonia. Fernaldia is nested within Echites and Peltastes is nested in Macropharynx. Fourteen genera are maintained. The new subtribe Laubertiinae is proposed, as are the combinations resulting from the merging of Fernaldia and Peltastes and the transfer of P. riedelii and T. ornata to Rhodocalyx and Prestonia, respectively. In the ancestors of Echiteae, we hypothesize that an evolutionary shift took place in which steroidal alkaloids and/or cardenolides, characteristic for apocynoids, were replaced by parsonsine-type pyrrolizidine alkaloids as the predominant defense compounds. [ABSTRACT FROM AUTHOR]

Endogenous cardenolides are digoxin-like substances and ouabain-like substances that have been implicated in the pathogenesis of hypertension and mood disorders in clinical and pre-clinical studies. Regulatory signals for endogenous cardenolides are still unknown. These endogenous compounds are believed to be produced by the adrenal gland in the periphery and the hypothalamus in the central nervous system, and constitute part of an hormonal axis that may regulate the catalytic activity of the α subunit of Na(+)/K(+)-ATPase. A review of literature suggests that there is great overlap in physiological environments that are associated with either elevations or reductions in the levels of atrial natriuretic peptide (ANP) and endogenous cardenolides. This suggests that these two factors may share a common regulatory signal or perhaps that ANP may be involved in the regulation of endogenous cardenolides. [ABSTRACT FROM AUTHOR]

The article focuses on study regarding cytotoxicity exhibited by the human renal adenocarcinoma and hepatocellular carcinoma cell lines. Topics discussed include results showing carcinoma-specific cytotoxicity exhibited by cardenolide glycosides towards hepatocellular carcinoma cells, presence of cytotoxicity due to upregulation of cyclin-dependent kinase inhibitor p21 and anticancer effects of cardiac glycosides exerted against several types of cancers.

Monarch butterflies are one of the best studied non-pest lepidopterans, serving as a model for migration, chemical ecology, and insect conservation. Despite the intensity with which the larvae and adults have been studied, the cryptic pupal stage is often difficult to study in the wild. It is perhaps due to this difficulty that researchers have largely overlooked monarchs' interactions with a pupal parasitoid, Pteromalus cassotis. Using field experiments in the northern U.S. and observational data from wild collected pupae in the southern U.S., we report occurrences of this host-parasitoid interaction at sites Minnesota, Georgia, Oklahoma, Texas, and Wisconsin. At sites in Minnesota, rates of parasitism of experimentally placed monarch were highly variable, ranging from 60% in 2010 to 0% in 2013 and 2014. Observations of wild-collected pupae suggest that rates of parasitism may near 100% at some sites in the southern U.S. The number of wasps emerging from a single host ranged from 1-425 (mean = 71). Later dissections of hosts revealed that, in some cases, dead parasitoids remained inside the host as larvae, pupae, and/or adults. Within a host, wasp sex ratios were typically female biased (median = 91% female), as is common in gregarious parasitic hymenopterans. Infected monarch pupae at a site in Oklahoma produced more wasps per host, more male-biased sex ratios, and had higher survival than hosts from other sites. We discuss the possibility that P. cassotis is a specialist on monarchs and perhaps closely related species, based on monarchs' sequestered cardenolides, published host records, and evidence for correlated population dynamics of this host and parasitoid. [ABSTRACT FROM AUTHOR]

The article presents a study on the phytochemical examination of the flowering plant Digitalis purpurea's seeds which resulted in the isolation of 15 cardenolide glycosides including three new compounds showing cytotoxicity against leukemia cells and human liver cancer cells. It mentions that the structure of glycosides was determined by nuclear magnetic resonance (NMR) spectroscopy. It reveals that the cytotoxic activity of cardenolide glycosides was reduced by addition of a hydroxy group.

Abstract: Two new strophanthidol cardenolides, toxicarioside N (1) and toxicarioside O (2), together with three known ones, were isolated from the seeds of Antiaris toxicaria. The structures of the new compounds were identified as strophanthidol-3-O-β-d-glucopyranosyl-(1→4)-6-deoxy-β-d-allopyranoside (1) and strophanthidol-3-O-β-d-glucopyranoside (2), respectively. The cytotoxic test showed that compounds 1 and 2 exhibited significant cytotoxicity against SMMC-7721 and K562. [Copyright &y& Elsevier]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Three new metabolites, 5-hydroxy-3,7-dimethoxyflavone-4′-O-β-glucopyranoside (1), 2β,19-epoxy-3β,14β-dihydroxy-19-methoxy-5α-card-20(22)-enolide (4) and β-anhydroepidigitoxigenin-3β-O-glucopyranoside (5), along with two known compounds, uzarigenine (2) and β-anhydroepidigitoxigenin (3), were isolated from Calotropis procera (Asclepiadaceae). The structure elucidation was accomplished mainly by nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric methods. To examine putative antimicrobial or cytotoxic activities, various bioassays were performed. Uzarigenine (2) demonstrated moderate cytotoxicity. [ABSTRACT FROM AUTHOR]

The article comments on an article about the use of digoxin in the treatment of chronic heart failure. The authors of the article recommended that digoxin should be used only in patients who are persistently symptomatic after they are stabilized by the current standard of care. Digoxin was withdrawn among patients with class IV heart failure and with a significant reduction in renal function in the Digitalis Investigation Group trial.