170,087 research outputs found
Les offrandes votives dans une perspective italienne
No full textBergonzi Giovanna, Piana Agostinetti Paola. Les offrandes votives dans une perspective italienne. In: Etudes Celtiques, vol. 28, 1991. Actes du IXe Congrès international d’études celtiques Première partie. Les Celtes au IIIe siècle avant J.-C. p. 465
The process of consensus building
No full textEvery day a large number of surgical procedures are carried out on an increasingly aging population. There is little evidence on how drugs and techniques used in the perioperative setting can affect mortality. Furthermore, due to the complexity and magnitude of the problem, this evidence is generally not readily available to physicians. Thus, the need for a Consensus Conference about perioperative medicine, debating only high-quality evidence from randomized controlled trials (RCTs), is evident
Donne del Piceno dall'età del ferro all'Orientalizzante.
No full textL'abbigliamento e il corredo delle sepolture femminili del Piceno permettono di formulare ipotesi sul ruolo sociale delle donne durante l'età del ferro e l'orientalizzante, quando si individuano personaggi femminili sepolti con un corredo complesso, che le distingue dal resto della popolazione. Nell’età arcaica, nel VI sec. a. C., la sepoltura più imponente finora conosciuta, tale da suggerire la possibilità che la signora ivi sepolta avesse svolto un ruolo politico eminente, è proprio quella di una dama sepolta a Numana (AN) con un corredo ricchissimo e resti di carri
A Validated Method for the Quality Control of Andrographis paniculata Preparations
No full textAndrographis paniculata is a herbal drug of Asian traditional medicine largely employed for the treatment of several diseases. Recently, it has been introduced in Europe for the prophylactic and symptomatic treatment of common cold and as an ingredient of dietary supplements. The active principles are diterpenes with andrographolide as the main representative. In the present study, an analytical protocol was developed for the determination of the main constituents in the herb and preparations of A. paniculata. Three different extraction protocols (methanol extraction using a modified Soxhlet procedure, maceration under ultrasonication, and decoction) were tested. Ultrasonication achieved the highest content of analytes. HPLC conditions were optimized in terms of solvent mixtures, time course, and temperature. A reversed phase C18 column eluted with a gradient system consisting of acetonitrile and acidified water and including an isocratic step at 30°C was used. The HPLC method was validated for linearity, limits of quantitation and detection, repeatability, precision, and accuracy. The overall method was validated for precision and accuracy over at least three different concentration levels. Relative standard deviation was less than 1.13%, whereas recovery was between 95.50% and 97.19%. The method also proved to be suitable for the determination of a large number of commercial samples and was proposed to the European Pharmacopoeia for the quality control of Andrographidis herba
Effects of Salvia miltiorrhiza on CNS Neuronal Injury and Degeneration: A Plausible Complementary Role of Tanshinones and Depsides
No full textSalvia miltiorrhiza is a very important herbal drug of traditional Chinese medicine. Bioactive constituents are represented by two main groups of secondary metabolites, the lipophilic diterpenic quinones known as tanshinones and the hydrophilic depsides known as salvianolic acids. S. miltiorrhiza extracts and single constituents have been shown to have positive effects in central nervous system neuronal injury and degeneration in several animal models by various biological mechanisms. Both tanshinones and depsides protect against β-amyloid-induced toxicity, but their mechanisms are complementary due to their different structure, the lipophilic tanshinones and the hydrophilic depsides. A number of anti-inflammatory mechanisms is also reported for both tanshinones and depsides. Common mechanisms are the effects on cytokines, inducible nitric oxide synthase, and glial fibrillary acidic protein. In addition, depsides are inhibitors of nitric oxide and cyclooxygenase-2, while tanshinones inhibit hypoxia-inducible factor-1α and nuclear factor kappa β. Both constituents can also modulate the protection of the central nervous system from oxidative stress with different but complementary mechanisms: tanshinones can enhance the activities of superoxide dismutase and glutathione peroxidase, while depsides can decrease reactive oxygen species. Furthermore, neuronal death underlies the symptoms of many human neurological disorders, including Alzheimer's, Parkinson's, and Huntington's diseases, stroke, and amyotrophic lateral sclerosis. Both classes of constituents can enhance the antiapoptotic B-cell leukemia protein-2 family members and decrease the translocation of cytochrome c, and, in addition, depsides decrease caspase-3 and intracellular Ca2+. Again, both classes of constituents have an activity on vascular endothelial growth factor but it is opposite, whereas tanshinones are inhibitors of acetylcholinesterase. Besides the extensive studies reporting on the biological mechanisms of depsides and tanshinones, pharmacokinetics studies are still very limited and not conclusive, especially for brain distribution. Further research is warranted to address the mechanisms of the multitarget actions of S. miltiorrhiza constituents and to translate this knowledge into clinical practice
The acetonation of methyl 5-C-methoxy-beta-D-galactopyranoside with 2,2-dimethoxypropane
No full textThe acetonation of methyl 5-C-methoxy-beta-beta-d-galactopyranoside (1a), masked bis-glycoside form
of L-arabino-hexos-5-ulose, with a large excess of 2,2-dimethoxypropane and catalytic amounts of
p-toluenesulfonic acid gives a mixture of five acetonides. The most abundant isolated product was
the mixed acetal methyl 6-O-(1-methoxy-1-methylethyl)-3,4-O-isopropylidene-5-C-methoxy-beta-d-
galactopyranoside (44% yield)
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