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1.
Soc Sci Med ; 340: 116388, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070307

RESUMO

While carers' vulnerability has often been neglected in the literature, the recent COVID-19 pandemic brought this issue to the fore. This article explores why it has been so often ignored and how could it be dealt with differently. It does so in the form of a philosophical and conceptual investigation illustrated by various examples and situations, related primarily, but not exclusively, to the COVID period. Criticising a property-based view, and based on examples of carers' vulnerability during the pandemic, our investigation suggests that carers' vulnerability is relationally constructed and played out on multiple interwoven dimensions that may contradict each other. Our examples also suggest that the relational construction of vulnerabilities is socially and organisationally mediated, calling for the development of social and organisational forms of mediation that may help carers deal with their vulnerabilities. Second, and rather counterintuitively with regard to the COVID-period, we question the negative valence usually associated with vulnerability and analyse how this affects ways of dealing with carers' vulnerabilities and the co-creation of care. Finally, following Gilson (2014), we propose an ambivalent, relational conception of vulnerability, considered as 'openness to affectation by' and offer some theoretical and practical implications. Theoretically, this conception also allows us to consider such openness as an ability that may nurture carers' 'response-ability'. It also allows us to develop specific relational ethics for and in care relationships. Practically, this re-conceptualisation may help carers better embrace and process their vulnerabilities, including responses to negative affectations following exposure to carees. It may also facilitate their 'reception' of carees, and help co-create and adapt responses to carees' calls, thus avoiding paternalistic responses.


Assuntos
Cuidadores , Pandemias , Humanos , Atitude do Pessoal de Saúde
2.
Am J Physiol Regul Integr Comp Physiol ; 325(5): R556-R567, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37694336

RESUMO

Lactate is now recognized as a regulator of fuel selection in mammals because it inhibits lipolysis by binding to the hydroxycarboxylic acid receptor 1 (HCAR1). The goals of this study were to quantify the effects of exogenous lactate on: 1) lipolytic rate or rate of appearance of glycerol in the circulation (Ra glycerol) and hepatic glucose production (Ra glucose), and 2) key tissue proteins involved in lactate signaling, glucose transport, glycolysis, gluconeogenesis, lipolysis, and ß-oxidation in rainbow trout. Measurements of fuel mobilization kinetics show that lactate does not affect lipolysis as it does in mammals (Ra glycerol remains at 7.3 ± 0.5 µmol·kg-1·min-1), but strongly reduces hepatic glucose production (16.4 ± 2.0 to 8.9 ± 1.2 µmol·kg-1·min-1). This reduction is likely induced by decreasing gluconeogenic flux through the inhibition of cytosolic phosphoenolpyruvate carboxykinase (Pck1, alternatively called Pepck1; 60% and 24% declines in gene expression and protein level, respectively). It is also caused by lactate substituting for glucose as a fuel in all tissues except white muscle that increases glut4a expression and has limited capacity for monocarboxylate transporter (Mct)-mediated lactate import. We conclude that lipolysis is not affected by hyperlactatemia because trout show no activation of autocrine Hcar1 signaling (gene expression of the receptor is unchanged or even repressed in red muscle). Lactate regulates fuel mobilization via Pck1-mediated suppression of gluconeogenesis and by replacing glucose as a fuel. This study highlights important functional differences in the Hcar1 signaling system between fish and mammals for the regulation of fuel selection.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/metabolismo , Ácido Láctico/metabolismo , Glicerol/metabolismo , Glucose/metabolismo , Mamíferos/metabolismo
3.
Phytochemistry ; 211: 113685, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37088350

RESUMO

Four previously undescribed alkaloids, aspergillinine A-D, and four known diterpene pyrones were isolated from the potato dextrose agar (PDA) culture of Aspergillus sp. HAB10R12. The chemical structures of the isolated compounds were elucidated based on a detailed analysis of their NMR and MS data. The absolute configuration of the isolated compounds was determined by Electronic Circular Dichroism analysis coupled with computational methods. Aspergillinine A represents the first example of a diketopiperazine dipeptide containing the unnatural amino acid N-methyl kynurenine. Its absolute configuration revealed that it adopts a rather unusual conformation. Aspergillinine B represents a previously unencountered skeleton containing an isoindolinone ring. Aspergillinine C and D were similar to previously isolated diketopiperazine alkaloids, namely, lumpidin and brevianamide F, respectively. The diterpene pyrones were isolated twice previously, once from a soil-derived Aspergillus species, and once from the liquid culture of Aspergillus sp. HAB10R12. The alkaloids isolated in this study showed no antiproliferative activity when tested against HepG2 and A549 cancer cell lines.


Assuntos
Alcaloides , Dicetopiperazinas , Dicetopiperazinas/química , Pironas/metabolismo , Estrutura Molecular , Aspergillus/química , Fungos/química , Alcaloides/química
4.
J Fish Biol ; 102(4): 913-923, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36704867

RESUMO

Due to their reported 'glucose-intolerant' phenotype, rainbow trout have been the focus of comparative studies probing underlying endocrine mechanisms at the organismal, tissue and molecular level. A particular focus has been placed on the investigation of the comparative role of insulin, an important glucoregulatory hormone, and its interaction with macronutrients. A limiting factor in the comparative investigation of insulin is the current lack of reliable assays to quantify circulating mature and thus bioactive insulin. To circumvent this limitation, tissue-specific responsiveness to postprandial or exogenous insulin has been quantified at the level of post-translational modifications of cell signalling proteins. These studies revealed that the insulin responsiveness of these proteins and their post-translational modifications are evolutionarily highly conserved and thus provide useful and quantifiable proxy indices to investigate insulin function in rainbow trout. While the involvement of specific branches of the intracellular insulin signalling pathway (e.g., mTor) in rainbow trout glucoregulation have been successfully probed through pharmacological approaches, it would be useful to have a functionally validated insulin receptor antagonist to characterize the glucoregulatory role of the insulin receptor pathway in its entirety for this species. Here, we report two separate in vivo experiments to test the ability of the mammalian insulin receptor antagonist, S961, to efficiently block insulin signalling in liver and muscle in response to endogenously released insulin and to exogenously infused bovine insulin. We found that, irrespective of the experimental treatment or dose, activation of the insulin pathway in liver and muscle was not inhibited by S961, showing that its antagonistic effect does not extend to rainbow trout.


Assuntos
Oncorhynchus mykiss , Receptor de Insulina , Animais , Bovinos , Receptor de Insulina/metabolismo , Receptor de Insulina/farmacologia , Oncorhynchus mykiss/genética , Antagonistas da Insulina/metabolismo , Antagonistas da Insulina/farmacologia , Glucose/metabolismo , Insulina/metabolismo , Fígado/metabolismo , Mamíferos
5.
Antibiotics (Basel) ; 11(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36139926

RESUMO

The emergence of multidrug-resistant bacteria and fungi requires the development of antibiotics and antifungal agents. This review identified natural products isolated from Asian angiosperms with antibacterial and/or antifungal activities and analyzed their distribution, molecular weights, solubility, and modes of action. All data in this review were compiled from Google Scholar, PubMed, Science Direct, Web of Science, ChemSpider, PubChem, and a library search from 1979 to 2022. One hundred and forty-one antibacterial and/or antifungal alkaloids were identified during this period, mainly from basal angiosperms. The most active alkaloids are mainly planar, amphiphilic, with a molecular mass between 200 and 400 g/mol, and a polar surface area of about 50 Å2, and target DNA and/or topoisomerase as well as the cytoplasmic membrane. 8-Acetylnorchelerythrine, cryptolepine, 8-hydroxydihydrochelerythrine, 6-methoxydihydrosanguinarine, 2'-nortiliacorinine, pendulamine A and B, rhetsisine, sampangine, tiliacorine, tryptanthrin, tylophorinine, vallesamine, and viroallosecurinine yielded MIC ≤ 1 µg/mL and are candidates for the development of lead molecules.

6.
Nat Chem ; 14(12): 1443-1450, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36123449

RESUMO

Ternatin-family cyclic peptides inhibit protein synthesis by targeting the eukaryotic elongation factor-1α. A potentially related cytotoxic natural product ('A3') was isolated from Aspergillus, but only 4 of its 11 stereocentres could be assigned. Here, we synthesized SR-A3 and SS-A3-two out of 128 possible A3 epimers-and discovered that synthetic SR-A3 is indistinguishable from naturally derived A3. Relative to SS-A3, SR-A3 exhibits an enhanced residence time and rebinding kinetics, as revealed by single-molecule fluorescence imaging of elongation reactions catalysed by eukaryotic elongation factor-1α in vitro. An increased residence time-stereospecifically conferred by the unique ß-hydroxyl in SR-A3-was also observed in cells. Consistent with its prolonged duration of action, thrice-weekly dosing with SR-A3 led to a reduced tumour burden and increased survival in an aggressive Myc-driven mouse lymphoma model. Our results demonstrate the potential of SR-A3 as a cancer therapeutic and exemplify an evolutionary mechanism for enhancing cyclic peptide binding kinetics via stereospecific side-chain hydroxylation.


Assuntos
Antineoplásicos , Imagem Individual de Molécula , Animais , Camundongos , Cinética , Antineoplásicos/farmacologia , Peptídeos Cíclicos/farmacologia
7.
Sci Rep ; 12(1): 5576, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35368037

RESUMO

Goldfish enter a hypometabolic state to survive chronic hypoxia. We recently described tissue-specific contributions of membrane lipid composition remodeling and mitochondrial function to metabolic suppression across different goldfish tissues. However, the molecular and especially epigenetic foundations of hypoxia tolerance in goldfish under metabolic suppression are not well understood. Here we show that components of the molecular oxygen-sensing machinery are robustly activated across tissues irrespective of hypoxia duration. Induction of gene expression of enzymes involved in DNA methylation turnover and microRNA biogenesis suggest a role for epigenetic transcriptional and post-transcriptional suppression of gene expression in the hypoxia-acclimated brain. Conversely, mechanistic target of rapamycin-dependent translational machinery activity is not reduced in liver and white muscle, suggesting this pathway does not contribute to lowering cellular energy expenditure. Finally, molecular evidence supports previously reported chronic hypoxia-dependent changes in membrane cholesterol, lipid metabolism and mitochondrial function via changes in transcripts involved in cholesterol biosynthesis, ß-oxidation, and mitochondrial fusion in multiple tissues. Overall, this study shows that chronic hypoxia robustly induces expression of oxygen-sensing machinery across tissues, induces repressive transcriptional and post-transcriptional epigenetic marks especially in the chronic hypoxia-acclimated brain and supports a role for membrane remodeling and mitochondrial function and dynamics in promoting metabolic suppression.


Assuntos
Carpa Dourada , Hipóxia , Animais , Epigênese Genética , Epigenômica , Expressão Gênica , Carpa Dourada/genética , Hipóxia/genética , Hipóxia/metabolismo
8.
PLoS One ; 17(3): e0265056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35259199

RESUMO

Dynamic contrast enhanced MRI (DCE-MRI) is a useful method to monitor therapy assessment in malignancies but must be reliable and comparable for successful clinical use. The aim of this study was to evaluate the inter- and intrarater reproducibility of DCE-MRI in lung cancer. At this IRB approved single centre study 40 patients with lung cancer underwent up to 5 sequential DCE-MRI examinations. DCE-MRI were performed using a 3.0T system. The volume transfer constant Ktrans was assessed by three readers using the two-compartment Tofts model. Inter- and intrarater reliability and agreement was calculated by wCV, ICC and their 95% confident intervals. DCE-MRI allowed a quantitative measurement of Ktrans in 107 tumors where 91 were primary carcinomas or intrapulmonary metastases and 16 were extrapulmonary metastases. Ktrans showed moderate to good interrater reliability in overall measurements (ICC 0.716-0.841; wCV 30.3-38.4%). Ktrans in pulmonary lesions ≥ 3 cm showed a good to excellent reliability (ICC 0.773-0.907; wCV 23.0-29.4%) compared to pulmonary lesions < 3 cm showing a moderate to good reliability (ICC 0.710-0.889; wCV 31.6-48.7%). Ktrans in intrapulmonary lesions showed a good reliability (ICC 0.761-0.873; wCV 28.9-37.5%) compared to extrapulmonary lesions with a poor to moderate reliability (ICC 0.018-0.680; wCV 28.1-51.8%). The overall intrarater agreement was moderate to good (ICC 0.607-0.795; wCV 24.6-30.4%). With Ktrans, DCE MRI offers a reliable quantitative biomarker for early non-invasive therapy assessment in lung cancer patients, but with a coefficient of variation of up to 48.7% in smaller lung lesions.


Assuntos
Meios de Contraste , Neoplasias Pulmonares , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes
9.
Quant Plant Biol ; 3: e24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37077965

RESUMO

Most approaches to estimate ecological value use monetary valuation. Here, we propose a different framework accounting ecological value in biophysical terms. More specifically, we are implementing the ecosystem natural capital accounting framework as an operational adaptation and extension of the UN System of Economic and Environmental Accounting/Ecosystem Accounting. The proof-of-concept study was carried out at the Rhône river watershed scale (France). Four core accounts evaluate land use, water and river condition, bio-carbon content of various stocks of biomass and its uses, and the state of ecosystem infrastructure. Integration of the various indicators allows measuring ecosystems overall capability and their degradation. The 12-year results are based on spatial-temporal geographic information and local statistics. Increasing levels of intensity of use are registered over time, that is, the extraction of resources surpasses renewal. We find that agriculture and land artificialisation are the main drivers of natural capital degradation.

10.
J Exp Biol ; 225(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34881781

RESUMO

Some hypoxia-tolerant species, such as goldfish, experience intermittent and severe hypoxia in their natural habitat, causing them to develop multiple physiological adaptations. However, in fish, the metabolic impact of regular hypoxic exposure on swimming performance in normoxia is less well understood. Therefore, we experimentally tested whether chronic exposure to constant (30 days at 10% air saturation) or intermittent hypoxia (3 h in normoxia and 21 h in hypoxia, 5 days a week) would result in similar metabolic and swimming performance benefits after reoxygenation. Moreover, half of the normoxic and intermittent hypoxic fish were put on a 20-day normoxic training regime. After these treatments, metabolic rate (standard and maximum metabolic rates: SMR and MMR) and swimming performance [critical swimming speed (Ucrit) and cost of transport (COT)] were assessed. In addition, enzyme activities [citrate synthase (CS), cytochrome c oxidase (COX) and lactate dehydrogenase (LDH)] and mitochondrial respiration were examined in red muscle fibres. We found that acclimation to constant hypoxia resulted in (1) metabolic suppression (-45% SMR and -27% MMR), (2) increased anaerobic capacity (+117% LDH), (3) improved swimming performance (+80% Ucrit, -71% COT) and (4) no changes at the mitochondrial level. Conversely, the enhancement of swimming performance was reduced following acclimation to intermittent hypoxia (+45% Ucrit, -41% COT), with a 55% decrease in aerobic scope, despite a significant increase in oxidative metabolism (+201% COX, +49% CS). This study demonstrates that constant hypoxia leads to the greatest benefit in swimming performance and that mitochondrial metabolic adjustments only provide minor help in coping with hypoxia.


Assuntos
Carpa Dourada , Hipóxia , Aclimatação/fisiologia , Animais , Consumo de Oxigênio/fisiologia , Natação/fisiologia
11.
Neurosci Lett ; 764: 136244, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34530116

RESUMO

Matching ATP supply and demand is key to neuronal hypoxia-tolerance and failure to achieve this balance leads to excitotoxic cell death in most adult mammalian brains. Ion pumping is the most energy-demanding process in the brain and some hypoxia-tolerant vertebrates coordinately down-regulate ion movement across neuronal membranes to reduce the workload of energy-expensive ion pumps, and particularly the Na+/K+-ATPase. Naked mole-rats are among the most hypoxia-tolerant mammals and achieve a hypometabolic state while maintaining brain [ATP] during severe hypoxia; however, whether ionic homeostasis is plastic in naked mole-rat brain is unknown. To examine this question, we exposed animals to 4 h of normoxia or moderate or severe hypoxia (11 or 3% O2, respectively) and measured changes in brain Na+/K+-ATPase activity. We found that 1) whole body metabolic rate decreased ∼25 and 75% in moderate and severe hypoxia, respectively, and 2) Na+/K+-ATPase activity decreased ∼50% in forebrain but increased 2-fold in cerebellum and was unchanged in brainstem. These results indicate that naked mole-rats acutely modulate brain energy demand in a region-specific manner to prioritize energy usage by the cerebellum. This may support exploration, navigation, and escape behaviours, while also enabling ATP savings when encountering hypoxia in nature.


Assuntos
Cerebelo/metabolismo , Metabolismo Energético/fisiologia , Hipóxia/metabolismo , Ratos-Toupeira/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Tronco Encefálico , Homeostase , Prosencéfalo , ATPase Trocadora de Sódio-Potássio/análise
12.
Metabolites ; 11(8)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34436444

RESUMO

Metabolic suppression is an essential strategy to cope with chronic hypoxia. This review examines the physiological processes used to survive in low oxygen environments. It proposes a novel mechanism-the remodeling of membrane lipids-to suppress ATP use and production. Temperature (homeoviscous adaptation), diet (natural doping in migrant birds) and body mass (membrane pacemaker of metabolism) have an impact on the lipid composition of membranes, which, in turn, modulates metabolic capacity. Vertebrate champions of hypoxia tolerance show extensive changes in membrane lipids upon in vivo exposure to low oxygen. These changes and those observed in hibernating mammals can promote the downregulation of ion pumps (major ATP consumers), ion channels, mitochondrial respiration capacity (state 3, proton leak, cytochrome c oxidase), and energy metabolism (ß-oxidation and glycolysis). A common membrane signal regulating the joint inhibition of ion pumps and channels could be an exquisite way to preserve the balance between ATP supply and demand in hypometabolic states. Membrane remodeling together with more traditional mechanisms could work in concert to cause metabolic suppression.

13.
J Exp Biol ; 224(15)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34374410

RESUMO

In rainbow trout, dietary carbohydrates are poorly metabolized compared with other macronutrients. One prevalent hypothesis suggests that high dietary amino acid levels could contribute to the poor utilization of carbohydrates in trout. In mammals, alanine is considered an important gluconeogenic precursor, but has recently been found to stimulate AMP-activated protein kinase (AMPK) to reduce glucose levels. In trout, the effect of alanine on glucose flux is unknown. The goal of this study was to determine the effects of 4 h exogenous alanine infusion on glucose metabolism in rainbow trout. Glucose flux, and the rate of glucose appearance (Ra) and disposal (Rd) were measured in vivo. Key glycolytic and gluconeogenic enzyme expression and activity, and cell signaling molecules relevant to glucose metabolism were assessed in the liver and muscle. The results show that alanine inhibits glucose Ra (from 13.2±2.5 to 7.3±1.6 µmol kg-1 min-1) and Rd (from 13.2±2.5 to 7.4±1.5 µmol kg-1 min-1) and the slight mismatch between Ra and Rd caused a reduction in glycemia, similar to the effects of insulin in trout. The reduction in glucose Rd can be partially explained by a reduction in glut4b expression in red muscle. In contrast to mammals, trout alanine-dependent glucose-lowering effects did not involve hepatic AMPK activation, suggesting a different mechanistic basis. Interestingly, protein kinase B (AKT) activation increased only in muscle, similar to effects observed in insulin-infused trout. We speculate that alanine-dependent effects were probably mediated through stimulation of insulin secretion, which could indirectly promote alanine oxidation to provide the needed energy.


Assuntos
Oncorhynchus mykiss , Alanina/metabolismo , Animais , Glicemia/metabolismo , Metabolismo dos Carboidratos , Gluconeogênese , Glucose/metabolismo , Insulina/metabolismo , Fígado/metabolismo , Oncorhynchus mykiss/metabolismo , Transdução de Sinais
15.
Metabolites ; 11(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33809959

RESUMO

Hypometabolism is a hallmark strategy of hypoxia tolerance. To identify potential mechanisms of metabolic suppression, we have used the goldfish to quantify the effects of chronically low oxygen (4 weeks; 10% air saturation) on mitochondrial respiration capacity and fuel preference. The responses of key enzymes from glycolysis, ß-oxidation and the tricarboxylic acid (TCA) cycle, and Na+/K+-ATPase were also monitored in various tissues of this champion of hypoxia tolerance. Results show that mitochondrial respiration of individual tissues depends on oxygen availability as well as metabolic fuel oxidized. All the respiration parameters measured in this study (LEAK, OXPHOS, Respiratory Control Ratio, CCCP-uncoupled, and COX) are affected by hypoxia, at least for one of the metabolic fuels. However, no common pattern of changes in respiration states is observed across tissues, except for the general downregulation of COX that may help metabolic suppression. Hypoxia causes the brain to switch from carbohydrates to lipids, with no clear fuel preference in other tissues. It also downregulates brain Na+/K+-ATPase (40%) and causes widespread tissue-specific effects on glycolysis and beta-oxidation. This study shows that hypoxia-acclimated goldfish mainly promote metabolic suppression by adjusting the glycolytic supply of pyruvate, reducing brain Na+/K+-ATPase, and downregulating COX, most likely decreasing mitochondrial density.

16.
Arthritis Rheumatol ; 73(11): 2078-2085, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33881225

RESUMO

OBJECTIVE: Silica is an environmental substance strongly linked with autoimmunity. The aim of this study was to assess the prevalence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and renal limited vasculitis, in a northeastern region of France and to evaluate whether there was a geospatial association between the localization of quarries in the region and the prevalence of these AAVs. METHODS: Potential AAV patients were identified using 3 sources: hospital records, immunology laboratories, and the French National Health Insurance System. Patients who resided in the Alsace region of France as of January 1, 2016 and who fulfilled the American College of Rheumatology criteria for GPA or the 2012 Chapel Hill Consensus Conference definitions for GPA or MPA were included. Incomplete case ascertainment was corrected using a capture-recapture analysis. The spatial association between the number of cases and the presence of quarries in each administrative entity was assessed using regression analyses weighted for geographic region. RESULTS: Among 910 potential AAV patients, we identified 185 patients fulfilling inclusion criteria: 120 patients with GPA, 35 patients with MPA, and 30 patients with renal limited vasculitis. The number of cases missed by any source as estimated by capture-recapture analysis was 6.4 (95% confidence interval [95% CI] 3.6-11.5). Accordingly, the estimated prevalence in Alsace in 2016 was 65.5 GPA cases per million inhabitants (95% CI 47.3-93.0), 19.1 MPA cases per million inhabitants (95% CI 11.3-34.3), and 16.8 renal limited vasculitis cases per million inhabitants (95% CI 8.7-35.2). The risk of AAV was significantly increased in communities with quarries (odds ratio 2.51 [95% CI 1.66-3.80]), and geographic-weighted regression analyses revealed a significant spatial association between the proximity to quarries and the number of GPA cases (P = 0.039). In analyses stratifying the AAV patients by ANCA serotype, a significant association between the presence of quarries and positivity for both proteinase 3 ANCAs (P = 0.04) and myeloperoxidase ANCAs (P = 0.03) was observed. CONCLUSION: In a region with a high density of quarries, the spatial association between the presence of and proximity to quarries and the prevalence of AAVs supports the idea that silica may have a role as a specific environmental factor in this disease.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/epidemiologia , Exposição Ambiental , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/etiologia , Criança , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
18.
J Nat Prod ; 83(12): 3564-3570, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33305943

RESUMO

Two new diterpene pyrones, asperginols A (1) and B (2), and four known analogues (3-6) were isolated from the endophytic fungus Aspergillus sp. HAB10R12. The structures and absolute configurations of these compounds were elucidated based on the analysis of their NMR, MS, and X-ray diffraction data. The revision of the absolute configurations at C-10, C-11, and C-14 of the known diterpene pyrones (3-6) and the determination of the configuration at the polyene side chain for compounds (4-6) were made using chemical methods and vibrational circular dichroism analysis. This group of diterpene pyrone compounds showed unique structural features including a 7/6/6 tricyclic diterpene moiety with an unusual trans-syn-trans stereochemical arrangement. Compound 6 showed moderate activity against the HT-29 colon cancer cell line.


Assuntos
Aspergillus/química , Diterpenos/química , Pironas/química , Estrutura Molecular , Análise Espectral/métodos
19.
J Nat Prod ; 83(12): 3493-3501, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33233893

RESUMO

Svalbardines A and B (1 and 2) and annularin K (3) were isolated from cultures of Poaceicola sp. E1PB, an endophyte isolated from the petals of Papaver dahlianum from Svalbard, Norway. Svalbardine A (1) is a pyrano[3,2-c]chromen-4-one, a new analogue of citromycetin. Svalbardine B (2) displays an unprecedented carbon skeleton based on a 5'-benzyl-spiro[chroman-3,7'-isochromene]-4,8'-dione core. Annularin K (3) is a hydroxylated derivative of annularin D. The structure of these new polyketides, along with those of known compounds 4-6, was established by spectrometric analysis, including extensive ESI-CID-MSn processing in the case of svalbardine B (2).


Assuntos
Ascomicetos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Regiões Árticas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Análise Espectral
20.
J Med Life ; 13(2): 183-186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742511

RESUMO

Clinical reasoning is the cornerstone of medical practice, and achieving this competence depends on a large number of factors. Internal medicine departments provide junior doctors with plentiful and varied patients, offering a comprehensive basis for learning clinical reasoning. In order to evaluate the usefulness of an early rotation at internal medicine departments, we compared, via script concordance tests, the evolution of residents' clinical reasoning after an initial internal medicine rotation compared to rotations through other medical specialties. Twenty-two residents were tested after six months of their internal medicine rotation and compared to twenty-five residents that had the first rotation in another specialty (control). We showed a significant difference in the improvement of the script concordance tests scores (p=0.015) between the beginning and the end of their first rotation between the internal medicine and the control groups, and this implies the lower improvement of clinical reasoning skills and spontaneous learning slope of the junior doctors in other departments.


Assuntos
Medicina Interna/educação , Internato e Residência , Aprendizagem , Competência Clínica , Avaliação Educacional , Humanos
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