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1.
Anat Sci Educ ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750636

RESUMO

This paper discusses the historical context of collaborative research and authorship disputes, exemplified by the complex relationship between Dutch anatomist and physician Gerard L. Blaes and his East-Central European mentee, Daniel Gödtke, during the study of medulla spinalis. The study employs historical analysis to unravel the dynamics of scholarly collaboration, emphasizing the significance of mentorship in scientific progress and the communal nature of knowledge exchange. This historical analysis is based on primary sources and historical records. It underscores Blaes's strategy to circumvent public confrontations regarding the authorship of the seminal work 'Anatome medullae spinalis, et nervorum inde provenientium' (1666). As a teacher, he facilitated his student's participation in a public disputation to avert public authorship conflicts over the book. This ultimately led to the publication of two distinct versions of 'Anatome medullae spinalis.' The first one was co-authored by the mentor and his mentee, while the latter was solely attributed to the mentor. This historical narrative raises essential questions about attributing individual contributions in medical sciences, echoing concerns still pertinent in contemporary academia. Additionally, it makes visible the power dynamics inherent in faculty-students relationships and the potential repercussions of authorship disputes on scholars' reputations. By drawing parallels between historical and modern authorship dilemmas, this study contributes to ongoing discussions on equitable authorship in scientific research and publishing. It not only highlights a historical precedent for the complex dynamics of mentor-mentee collaborations and authorship disputes but also illuminates how these practices continue to influence contemporary academic and publishing customs.

2.
Eur J Heart Fail ; 25(8): 1323-1333, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37042083

RESUMO

AIMS: Diuretic response in heart failure is blunted when compared to healthy individuals, but the pathophysiology underlying this phenomenon is unclear. We aimed to investigate whether the diuretic resistance mechanism is related to insufficient furosemide tubular delivery or low tubular responsiveness. METHODS AND RESULTS: We conducted a prospective, observational study of 50 patients with acute heart failure patients divided into two groups based on previous furosemide use (furosemide naïve: n = 28 [56%] and chronic furosemide users: n = 22 [44%]). Each patient received a protocol-derived, standardized furosemide dose based on body weight. We measured diuretic response and urine furosemide concentrations. The furosemide naïve group had significantly higher urine volumes and natriuresis when compared to chronic users at all timepoints (all p < 0.05). Urine furosemide delivery was similar in furosemide naïve versus chronic users after accounting for differences in estimated glomerular filtration rate (28.02 [21.03-35.89] vs. 29.70 [18.19-34.71] mg, p = 0.87). However, the tubular response to delivered diuretic was dramatically higher in naïve versus chronic users, that is the urine volume per 1 µg/ml of urine furosemide at 2 h was 148.6 ± 136.1 versus 50.6 ± 56.1 ml (p = 0.005). CONCLUSIONS: Patients naïve to furosemide have significantly better diuresis and natriuresis when compared to chronic furosemide users. The blunted diuretic response in patients with chronic loop diuretic exposure is driven by decreased tubular responsiveness rather than insufficient furosemide tubular delivery.


Assuntos
Furosemida , Insuficiência Cardíaca , Humanos , Diuréticos/uso terapêutico , Inibidores de Simportadores de Cloreto de Sódio e Potássio , Insuficiência Cardíaca/tratamento farmacológico , Estudos Prospectivos , Estudos Observacionais como Assunto
3.
Molecules ; 27(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35566305

RESUMO

Deep eutectic solvents (DES), compared to classic ones, have interesting properties, such as the ability to solubilize compounds differing in polarity or increased dissolution of selected chemical compounds. They also offer specific interactions between the mobile and stationary phases. Those features make them promising solvents in chromatographic techniques, including the use in the separation of complicated samples. The first quantitative analysis with eutectic thin-layer chromatography (TLC) is presented in the paper. As a case study, five alkaloids from Chelidonium maius were selected as target compounds. A wide range of terpene-based DESs was investigated to develop the chromatographic system, both pure and after dilution. Moreover, a novel approach was employed to adjust polarity, involving mixing DESs differing in chromatographic properties. This procedure has proved to be effective. The best results were obtained with a 2:1 (wt/wt) mixture of DESs: camphor + phenol and menthol + limonene, with a 20% addition of methanol. The chromatographic system was validated and checked on the real sample, which made it the first applicable and operational quantitative eutectic TLC system.


Assuntos
Alcaloides , Chelidonium , Alcaloides/química , Chelidonium/química , Cromatografia em Camada Fina/métodos , Extratos Vegetais/química , Solventes/química
4.
J Ethnopharmacol ; 281: 114535, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34416297

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Theriac is considered the most popular cure-all multi-ingredient medicine and has been used for more than two millennia. It has also been used as one of the most important anti-epidemic drugs up to the 19th c., treated as an emergency medicine in case of e.g. bubonic plague. AIM OF THE STUDY: Until now, no reliable information regarding the pharmacological effect of the treacle was available, including its possible toxic or narcotic properties. In order to change the state of knowledge in this matter we have selected the Theriac recipe that had been actually used for producing the treacle in 1630, which was confirmed by the official municipal documents of the time. METHODS: The recipe was written in Latin, with the use of pre-Linnean nomenclature and then apothecary common names, which required translation into the modern scientific language in order to get reliable pharmacological conclusions. The information from historical sources has been compiled with the pharmacological data concerning the most potent compounds, which for the first time made it possible to calculate the amounts of active compounds in the doses taken by then patients. RESULTS: Only two species included in Theriac can be harmful in humans: poppy and sea squill, but in both cases the calculated quantity of morphine and cardiac glycosides, respectively, were below toxic level. There are no indications, both from the historical and pharmacological point of view, for Theriac being toxic or narcotic in patients, when used as prescribed. CONCLUSIONS: As for now, the most probable is that the treacle owed its postulated efficacy in the main indications to the placebo effect. Still, the results should be further confirmed by reconstructing the actual Theriac and subjecting it to modern tests and analyses.


Assuntos
Antídotos/história , Antídotos/farmacologia , Venenos , Charlatanismo , Antídotos/química , Combinação de Medicamentos , Europa (Continente) , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História Antiga , História Medieval , Humanos , Materia Medica
5.
J Chromatogr A ; 1621: 461044, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32273090

RESUMO

The presented paper is the first to show thin layer chromatography (TLC) analysis based on eutectic mobile phases (Deep Eutectic Solvents - DES). During the experiment 25 eutectic mixtures were investigated for their chromatographic properties. Most of them belong to the natural deep eutectic solvents (NADES) group. Also, new eutectic liquids based on phenolics and terpenes, not previously employed in analytical practice, were tested. The eutectic liquids were investigated as pure or diluted with solvents used in chromatographic routine: methanol, water, acetone, chloroform or diethyl ether. The analyses were carried out using classic and high performance silica gel plates. The working solution was a mixture of five alkaloids found in genus Chelidonium, namely sanguinarine, coptisine, chelerythrine, chelidonine, and berberine, with UV light detection of 366 nm. This report proves that eutectic TLC is possible and that the eutectic interactions play a crucial role in the separation process. In most of the tested modifications at least partial separation was achieved. The most successful mobile phase, which enabled separation of all the tested alkaloids, was the equimolar mixture of menthol and phenol with a 35% addition of methanol. The system was also effective in separating alkaloids in the real Chelidonium maius extract sample.


Assuntos
Cromatografia em Camada Fina/métodos , Alcaloides/análise , Chelidonium/química , Fenóis/química , Extratos Vegetais/química , Solventes/química , Terpenos/química
6.
Appl Biochem Biotechnol ; 175(3): 1576-87, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25413794

RESUMO

Microshoot cultures of the Chinese medicinal plant Securinega suffruticosa (Pall.) Rehd. were established and evaluated for the presence of therapeutically relevant indolizidine alkaloids securinine (S) and allosecurinine (AS). The cultures were maintained in shake flasks (SFs) and a bubble column bioreactor (BCB) using the modified Murashige's shoot multiplication medium supplemented with 1.0 mg l(-1) benzyladenine (BA), 3.0 mg l(-1) 2-isopentenyladenine (2iP), and 0.3 mg l(-1) 1-naphthaleneacetic acid (NAA). The influence of light and medium supplementation strategies with biosynthesis precursor (lysine (LY)) and nutrient formulations (casein hydrolysate (CH) and coconut water (CW)) on biomass growth and alkaloid production were investigated. SF cultures grown in the presence of light yielded up to 6.02 mg g(-1) dry weight (DW) S and 3.70 mg g(-1) DW AS, corresponding to the respective productivities of 98.39 and 60.21 mg l(-1). Among feeding experiments, CW supplementation proved most effective for SF-grown shoots, increasing biomass yield and AS productivity by 52 and 44 %, respectively. Maximum concentrations of securinine (3.25 mg g(-1) DW) and allosecurinine (3.41 mg g(-1) DW) in BCB cultures were achieved in the case of 1.0 g l(-1) LY supplementation. These values corresponded to the productivities of 42.64 and 44.47 mg per bioreactor, respectively.


Assuntos
Alcaloides/biossíntese , Alcaloides/uso terapêutico , Biotecnologia/métodos , Euphorbiaceae/química , Indolizidinas/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Azepinas/metabolismo , Biomassa , Reatores Biológicos , Meios de Cultura/farmacologia , Euphorbiaceae/efeitos dos fármacos , Euphorbiaceae/efeitos da radiação , Compostos Heterocíclicos de Anel em Ponte/metabolismo , Indolizidinas/uso terapêutico , Lactonas/metabolismo , Luz , Piperidinas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/efeitos da radiação
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