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In this study, thirty-four samples of Laggera crispata (Vahl) Hepper & J. R. I. Wood from five main production areas in Yunnan Province, were collected for experimentation. UPLC- PDA was used to generate fingerprints and the common peaks were analysed through R and SIMCA-P. L. crispata from different origins can be distinguished by OPLS-DA and PCA. The VIP values were compared, and 8 characteristic components with great differences were obtained. It was confirmed that the two characteristic components were chrysosplenetin and artemisetin, and the quantitative analysis was performed with these two compounds from L. crispata samples with different origins. Based on the variance analysis results, the most significant difference in the content of chrysosplendin and artemisin was in Lancang and Honghe and Lancang and Simao, respectively. The chrysosplenetin can be used as an important indicator for quality control and to trace the origin of L. crispata.
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Apparent negative crack growth is often encountered when performing elastic-plastic fracture toughness tests with the Elastic Compliance single-specimen technique. It consists of a decrease of specimen compliance (reduction of crack size) during the early portion of the test, before the attainment of maximum force and the onset of ductile crack extension. This phenomenon was recognized and discussed inside the fracture mechanics community since the mid-1980s, but widespread consensus was never achieved on its root causes and on the best approach to account for it in the analysis of an elastic-plastic fracture toughness test. It has been shown that both experimental (test setup) and material behavior aspects can be invoked to explain the decrease of elastic compliance that translates into decreasing crack size in the early loading stage. The current edition of ASTM E1820, Standard Test Method for Measurement of Fracture Toughness, does not offer provisions to handle this phenomenon, and users are left free to treat the issue as they see fit. In this study, several articles published in the last 40 years were reviewed, and different proposed methods were applied on 15 selected tests performed on specimens of different geometries and thicknesses. Comparisons between original crack sizes, ductile crack extensions, and critical toughness values are presented, and recommendations are provided for revising ASTM E1820 with due consideration of the occurrence of apparent negative crack growth.
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Nine undescribed sesquiterpenoids, along with ten known compounds, were isolated from the ethyl acetate extract of Mansonia gagei heartwood. Their structures were determined by spectroscopic data analysis (FTIR, 1D, 2D NMR, and HRESIMS), and their absolute configurations were established by ECD calculation. The isolated compounds were evaluated for their inhibitory effect against α-glucosidase from yeast. The results showed that mansonone U, mansonialactam, heliclactone and mansonone S exhibited exceptionally potent activities when compared to the positive control, acarbose, with IC50 values of 12.38 ± 0.71, 0.20 ± 0.05, 13.12 ± 2.85, and 12.05 ± 1.91 µM, respectively. Among them, mansonialactam possessed the most potent inhibitory activity against yeast α-glucosidase, and it showed an uncompetitive inhibition mode.
Assuntos
Malvaceae , Sesquiterpenos , alfa-Glucosidases , Saccharomyces cerevisiae , Espectroscopia de Ressonância Magnética , Malvaceae/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura MolecularRESUMO
Six undescribed prenylated chalcones gagones A-F were isolated from the acetone fraction of Mansonia gagei heartwood. Their structures were unambiguously established based on spectroscopic analysis (HRESIMS, 1D and 2D NMR), as well as comparison to literature data. Their absolute configurations were elucidated using DP4 and electronic circular dichroism calculations. Isolated compounds were evaluated for their inhibitory activity against α-glucosidase and DPPH assay. All of the tested compounds exhibited better activity than that of acarbose (IC50 93.6 ± 0.5 µM). Among them, gagone D exhibited the highest α-glucosidase inhibitory with the IC50 value of 3.6 ± 0.4 µM. For antioxidant activity, gagones A-C, and E showed more active than that of ascorbic acid (IC50 30.2 ± 0.5 µM) with the IC50 values of 13.2 ± 0.7, 20.1 ± 0.4, 19.3 ± 0.5 and 12.8 ± 0.2 µM, respectively.
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Chalconas , Malvaceae , Chalconas/farmacologia , Estrutura Molecular , alfa-Glucosidases , Espectroscopia de Ressonância Magnética , Malvaceae/químicaRESUMO
After the discovery of insulin at the University of Toronto in 1921-22, Frederick Banting and Charles Best downplayed the contributions of physiology professor John James Rickard Macleod, the director of the laboratory where the discovery was made. Banting and Best, their allies, and to a lesser extent the university promoted a "fairy tale" version in which the two young investigators made the discovery on their own, creating the so-called "Banting and Best myth." Over the next 60 years, the myth prevailed and Macleod's reputation became increasingly tarnished, with both Banting and Best actively maligning their former mentor. While the publication of Michael Bliss' The Discovery of Insulin in 1982 placed Macleod's reputation on the road to recovery, there are still many lingering issues that have been raised, and Macleod remains misunderstood, misinterpreted, and maligned. This paper, using primary and secondary historical sources, addresses topics that have been repetitively raised by Macleod's detractors over the past century.
Résumé. Après la découverte de l'insuline à l'Université de Toronto en 19211922, Frederick Banting et Charles Best ont minimisé les contributions du professeur de physiologie John James Rickard Macleod, directeur du laboratoire où la découverte a été faite. En compagnie de leurs alliés et dans une certaine mesure de l'Université, Banting et Best ont propagé un conte de fée dans lequel les deux jeunes chercheurs auraient fait cette découverte par eux-mêmes, donnant ainsi naissance au « mythe Banting et Best ¼. Au cours des 60 années suivantes, ce mythe a prévalu et la réputation de Macleod a été ternie, Banting et Best s'employant à calomnier leur ancien mentor. Si la publication de The Discovery of Insulin (1982) par Michael Bliss a quelque peu rétabli la réputation de Macleod, celui-ci est encore largement incompris, mal interprété et dénigré. En s'appuyant sur des sources historiques premières et secondaires, cet article aborde les enjeux qui ont été soulevés de manière répétée par les détracteurs de Macleod au cours du XXe siècle.
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Insulina , História do Século XX , Humanos , Insulina/história , CanadáRESUMO
An introduction to the special issue of the Canadian Journal of Health History/Revue canadienne d'histoire de la santé on J.J.R. Macleod, a co-discoverer of insulin.
Résumé. Introduction au numéro spécial du Canadian Journal of Health History/Revue canadienne d'histoire de la santé sur J.J.R. Macleod, codécouvreur de l'insuline.
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Insulina , Canadá , Humanos , História do Século XXRESUMO
On 7 November 1923, when J.J.R. Macleod announced that he would split his half of the Nobel Prize with J.B. Collip, following F.G. Banting splitting his half of the prize with C.H. Best, a reporter asked Macleod to assess his share in the discovery of insulin. "Oh, I was only the impresario - the managing director," he replied. Whether Macleod deserved the recognition with Banting of the Nobel Committee for the discovery of insulin, it is certainly clear that the discovery, and especially its efficient development into a remarkably effective diabetes treatment, would not have happened without Macleod's knowledge and laboratory research experience. Nor would it have happened without his leadership and, especially, without his acumen as the managing director, or impresario, of the insulin enterprise.
Résumé. Le 7 novembre 1923, lorsque J.J.R. Macleod annonça qu'il allait partager sa part du Prix Nobel avec J.B. Collip imitant ainsi F.G. Banting, qui avait partagé la sienne avec C.H. Best , un journaliste demanda à Macleod d'évaluer sa contribution à la découverte de l'insuline. « Oh, je n'étais que l'impresario, le directeur général ¼, répondit-il. Que Macleod mérite ou non la récompense que le Comité du prix Nobel lui décerna conjointement avec Banting, il est certain que la découverte de l'insuline, qui déboucha sur un traitement remarquablement efficace du diabète, n'aurait pas eu lieu sans les connaissances et l'expérience de Macleod en matière de recherche en laboratoire. Elle n'aurait pas non plus eu lieu sans son leadership et, surtout, sans sa perspicacité en tant que directeur général ou impresario.
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Insulina , Prêmio Nobel , Insulina/história , História do Século XX , Humanos , Canadá , Diabetes Mellitus/história , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/terapiaRESUMO
This work presents the development of a J-integral estimation procedure for deep and shallow cracked bend specimens based upon plastic ηpl factors for a butt weld made in an S690 QL high strength low alloyed steel. Experimental procedures include the characterization of average material properties by tensile testing and evaluation of base and weld metal resistance to stable tearing by fracture testing of square SE(B) specimens containing a weld centerline notch. J-integral has been estimated from plastic work using a single specimen approach and the normalization data reduction technique. A comprehensive parametric finite element study has been conducted to calibrate plastic factor ηpl and geometry factor λ for various fixture and weld configurations, while a corresponding plastic factor γpl was computed on the basis of the former two. The modified ηpl and γpl factors were then incorporated in the J computation procedure given by the ASTM E1820 standard, for evaluation of the plastic component of J and its corresponding correction due to crack growth, respectively. Two kinds of J-R curves were computed on the basis of modified and standard ηpl and γpl factors, where the latter are given by ASTM E1820. A comparison of produced J-R curves for the base material revealed that variations in specimen fixtures can lead to ≈10% overestimation of computed fracture toughness JIc. Furthermore, a comparison of J-R curves for overmatched single-material idealized welds revealed that the application of standard ηpl and γpl factors can lead to the overestimation of computed fracture toughness JIc by more than 10%. Similar observations are made for undermatched single material idealized welds, where fracture toughness JIc is overestimated by ≈5%.
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The history of modern psychiatry in China began at the end of the nineteenth century, as a result of the work of missionaries. Soochow was one of the first cities to establish a hospital for the treatment of mental patients, but historians knew little about it. It provided a valuable service from 1898 to 1937. In the 1930s, there were 200 beds in the psychiatry and neurology section, making it the most influential psychiatric hospital in East China. After Soochow was occupied by the Japanese army in 1937, the hospital was destroyed and shut down.
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Hospitais Psiquiátricos/história , Missionários/história , Psiquiatria/história , China , Feminino , História do Século XIX , História do Século XX , Humanos , Masculino , Unidade Hospitalar de Psiquiatria/história , Sífilis/tratamento farmacológico , Sífilis/história , Estados UnidosRESUMO
At the turn of the 18th and 19th centuries, when pharmacy was established as a modern scientific discipline, pharmacists played an important role in spreading the latest discoveries in the field of chemistry, being virtually the only established representatives of the field. The article focuses on a mutually enriching dialogue between the prominent personality of the time - the poet, writer and statesman, as well as the scientist - Johann Wolfgang von Goethe and the major representatives of the pharmacy of that time, especially J. R. Spielmann, W. H. Buchholz, J. F. Göttling, and J. W. Döbereiner. Goethe, who has been deeply interested in chemistry all over his life, has found his teachers of chemistry and co-workers in this field among the pharmacists and, in return, has provided them with an extraordinary support for the realization of their scientific and professional interests. This cooperation is illustrated by the solution of the mysterious method of poisoning described in the ancient literature, on which the poet collaborated with J. W. Döbereiner. Attention is also paid to the reflection of pharmacy in Goethe's work (Hermann und Dorothea, Faust). The poet's numerous stays in Bohemia, where he spent more than three years of his life, naturally brought him into contact with a number of pharmacists of the Czech Kingdom.
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História da Farmácia , Farmacêuticos , Alemanha , História do Século XVIII , História do Século XIX , HumanosRESUMO
Synapses are essential units for the flow of information in the brain. Over the last 70 years, synapses have been widely studied in multiple animal models including worms, fruit flies, and rodents. In comparison, the study of human synapses has evolved significantly slower, mainly because of technical limitations. However, three novel methods allowing the analysis of molecular, morphological, and functional properties of human synapses may expand our knowledge of the human brain. Here, we briefly describe these methods, and evaluate how the information provided by each unique approach may contribute to the functional and anatomical analysis of the synaptic component of human brain circuitries. In particular, using tissue from cryopreserved human brains, synaptic plasticity can be studied in isolated synaptosomes by fluorescence analysis of single-synapse long-term potentiation (FASS-LTP), and subpopulations of synapses can be thoroughly assessed in the ribbons of brain tissue by array tomography (AT). Currently, it is also possible to quantify synaptic density in the living human brain by positron emission tomography (PET), using a novel synaptic radio-ligand. Overall, data provided by FASS-LTP, AT, and PET may significantly contribute to the global understanding of synaptic structure and function in both healthy and diseased human brains, thus directly impacting translational research.
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The Direct Current Electrical Potential Difference (DCEPD) technique has been used for many years in fatigue and fracture testing for monitoring crack propagation in metallic materials. The principle of DCEPD methods is that when a constant current flows through a cracked specimen, the voltage change measured across the crack plane can be analytically related, empirically related, or both, to the change in crack size. In fatigue testing, performed within the limits of Linear Elastic Fracture Mechanics, crack propagation is the sole source of potential change. In ductile fracture testing, additional contributions from specimen dimension changes and crack-tip plastic deformation (blunting) have to be accounted for and distinguished from the DCEPD increase caused by crack growth. The ASTM E08.07.09 Task Group, formed in 2013 and chaired by the author, has been developing an annex for ASTM E1820, Standard Test Method for Measurement of Fracture Toughness, which focuses on the use of DCEPD measurements for the prediction of crack size and crack extension in ductile fracture toughness tests. This article presents the analysis of an analytical round-robin, in which 8 participants analyzed 24 existing fracture toughness data sets using two different approaches, based on the analysis of the displacement versus DCEPD and force versus DCEPD, respectively. The comparison between these two approaches and the implications for the ASTM E1820 annex being developed are the focus of this article.
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Objective: To study the chemical constituents from the roots of Schefflera octophylla. Methods: The constituents were isolated and purified by repeated column chromatography on silica, Sephadex LH-20 gel, and HPLC. Their structures were elucidated by spectral analysis. Results: Eleven compounds were isolated and identified as 2α,3β,23α-trihydroxy-urs-12-ene-28-oic acid-28-O-β-D-glucopyranoside (1), 3α-hydroxy-urs-12-ene-23,28-dioic acid 28-O-α-L-rhamnopyranosy1 (1→4)-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside (2), asiaticoside (3), decanol (4), octadecanol (5), lignoceric acid (6), octacosanoic acid (7), hexadecanoic acid (8), isovanillin (9), vanillin (10), and 2-hydroxy-4-(octyloxy) benzophenone (11). Conclusion: Compound 1 is isolated from the plants of Schefflera J. R. G. Forst. for the first time and compounds 4-11 are obtained from this plant for the first time.
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BACKGROUND: The peptide mastoparan 7 (MST7) stimulated ATP release in human erythrocytes. We explored intra- and extracellular processes governing the time-dependent accumulation of extracellular ATP (i.e., ATPe kinetics). METHODS: Human erythrocytes were treated with MST7 in the presence or absence of two blockers of pannexin 1. ATPe concentration was monitored by luciferin-luciferase based real-time luminometry. RESULTS: Exposure of human erythrocytes to MST7 led to an acute increase in [ATPe], followed by a slower increase phase. ATPe kinetics reflected a strong activation of ATP efflux and a low rate of ATPe hydrolysis by ectoATPase activity. Enhancement of [ATPe] by MST7 required adhesion of erythrocytes to poly-D-lysin-coated coverslips, and correlated with a 31% increase of cAMP and 10% cell swelling. However, when MST7 was dissolved in a hyperosmotic medium to block cell swelling, ATPe accumulation was inhibited by 49%. Erythrocytes pre-exposure to 10µM of either carbenoxolone or probenecid, two blockers of pannexin 1, exhibited a partial reduction of ATP efflux. Erythrocytes from pannexin 1 knockout mice exhibited similar ATPe kinetics as those of wild type mice erythrocytes exposed to pannexin 1 blockers. CONCLUSIONS: MST7 induced release of ATP required either cell adhesion or strong activation of cAMP synthesis. Part of this release required cell swelling. Kinetic analysis and a data driven model suggested that ATP efflux is mediated by two ATP conduits displaying different kinetics, with one conduit being fully blocked by pannexin 1 blockers. GENERAL SIGNIFICANCE: Kinetic analysis of extracellular ATP accumulation from human erythrocytes and potential effects on microcirculation.
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Trifosfato de Adenosina/metabolismo , Eritrócitos/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Cães , Eritrócitos/metabolismo , Humanos , Hidrólise , Peptídeos e Proteínas de Sinalização Intercelular , Cinética , Camundongos , Camundongos Knockout , Transdução de SinaisRESUMO
Objective: To study the chemical constituents from the roots of Breynia fruticosa. Methods: The compounds were isolated by comprehensive column chromatography, and the structures were elucidated by spectral methods. Results: Thirteen compounds were isolated and elucidated, including four triterpenoids, friedelin (1), friedelinol (2), lupenone (3), and glochidiol (4); three steroids, including β-sitosterol (5), stigmastane-3β, 6β-diol (6), and β-sitosterylglucoside-6'-octadecanoate (7); two cerebrosides, including 1-O-β-D-glucopyranosyl-(2S, 3R, 4E, 8Z)-2-[(2-hydroxyoctadecanoyl) amido]-4, 8-octadecadiene-1, 3-diol (8) and 1-O-β-D-glucopyranosyl-(2S, 3S, 4R, 8Z)-2-[(2R)-2-hydroxypentacosanoylamino]-8-octadecene-1, 3, 4-triol (9); and four other compounds, including (-)-epicatchin (10), ε-caprolactone (11), aviculin (12), and vanillin (13). Conclusion: Compounds 3, 4, 6-9, and 11 are isolated from the plant of Breynia J. R. et G. Forst. nom. cons. for the first time, and compound 11 is isolated from the natural product for the first time.
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Defesa da Criança e do Adolescente/legislação & jurisprudência , Internação Compulsória de Doente Mental/legislação & jurisprudência , Mau Uso de Serviços de Saúde , Hospitais Psiquiátricos , Adolescente , Criança , Coerção , Erros de Diagnóstico , Hospitais Psiquiátricos/economia , Humanos , Menores de Idade , Pais , Autonomia Pessoal , Decisões da Suprema Corte , Estados UnidosAssuntos
Adolescente , Direitos Civis , Internação Compulsória de Doente Mental , Função Jurisdicional , Jurisprudência , Pessoas Mentalmente Doentes , Menores de Idade , Recusa do Paciente ao Tratamento , Liberdade , Instituições Privadas de Saúde , Hospitais Psiquiátricos , Humanos , Transtornos Mentais , Consentimento dos Pais , Admissão do Paciente , Privacidade , Decisões da Suprema Corte , Consentimento do Representante Legal , Estados Unidos , WashingtonRESUMO
The hospitalization of children in psychiatric hospitals and their associated rights or lack thereof remains an important issue. Much attention has been focused on children's rights in Florida, most recently with the cases of Gregory K. and Kimberly Mays. On a national level, Hillary Rodham Clinton has drawn attention to children's rights through her advocacy for children. The commitment of children to mental health facilities in Florida deserves examination. This is an important issue, not only to the psychiatrist who tests youths, but also to the family practitioner, internist, or any other referring physician who is involved in the case of the child and the family. It is imperative that the primary care physician as well as the psychiatrist know and understand the limitations and requirements for civil commitment of a child in a psychiatric setting.