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The reactions of N-sulfonylhydrazones derived from cyclic ketones with γ-azidopropylboronic acid and 2-(azidomethyl)phenylboronic acid give rise to spirocyclic pyrrolidines and spiroisoindolines, respectively. The reactions proceed without the need of any transition-metal catalyst through a domino process that comprises the formation of a Csp3 -C and a Csp3 -N bond of the former hydrazonic carbon. The scope of the reaction has been explored by the preparation of over 50 examples of NH-unprotected spirocyclic derivatives. Importantly, this methodology could be applied for the preparation of alkaloid steroids from steroid N-tosylhydrazones.
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The reaction between γ-azido-N-tosylhydrazones and boronic acids leads to the obtention of 2,2-disubstituted pyrrolidines in a domino process that includes 1)â diazoalkane formation, 2)â intermolecular carboborylation of the diazocompound, and 3)â intramolecular carborylation of the azide, and comprises the formation of a Csp3 -Csp3 and a Csp3 -N bonds on the same carbon atom. The reaction proceeds without the need of any transition-metal catalyst under microwave activation and features wide scope in both reaction partners. It can be applied to both alkyl and arylboronic acids with equal efficiency. With N-tosylhydrazones derived from 2-(2-azidoethyl)-cyclopentanone and cyclohexanone the reactions are highly diastereoselective leading to the cis-fused bicyclic systems as unique diastereoisomers. The scope of the process is illustrated by over sixty examples, including scaffolds present in natural alkaloids, and the mechanistic proposal is suppported by DFT-based computations.
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The cascade reaction between N-tosylhydrazones and 2-alkynylpyridines leads to 2-(pyrazol-3-yl)pyridines, important structural motifs in ligands for transition metals and bioactive molecules. When the reaction is conducted with 2,6-diethynylpyridine, the important 2,6-bis(pyrazolyl)pyridines are obtained, featuring the arrangement of tridentate and also pentadentate ligands. A novel three-component version of the reaction has been designed, which involves the use of α-bromo-N-tosylhydrazones, alkynylpyridines and NH-azoles. The generality of the multicomponent reaction is further illustrated by the preparation of different polysubstituted pyrazoles by employing an array of terminal alkynes. In these multicomponent reactions, complex molecules featuring three different heterocycles are assembled in a single step from commercial materials, enabling the fast generation of molecular diversity.
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8-Isoquinolinones derived from a silver-catalyzed cycloisomerization of in situ formed ortho-alkynylsalicylaldimines react with 1 equiv of acetylenedicarboxylate derivatives to give pyrano[2,3,4- ij]isoquinolines through a [4 + 2]-cycloaddition reaction. When 2 equiv of the alkyne are used, structurally complex benzo[ de]chromenes are obtained through an intricate cascade process comprising unusual formal [4 + 2]- and [2 + 2]-cycloadditions followed by several ring-opening and ring-closing processes.
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The international recommendations of the management of asthma have been modified last years. Several therapies used since long time have no place in the management of moderate asthma today. The use of targeted immunotherapies against phenotypes of asthma are used more and more. Inhalant therapies are becoming more targeted towards the patient's wishes. This article specifies the novelties in management of asthma for de general practitioner, including the use of short acting beta2-agonists, which are no longer to be used without inhaled corticosteroid.
Les recommandations internationales de la prise en charge de l'asthme ont été modifiées ces dernières années. Plusieurs thérapies utilisées de longue date n'ont plus leur place dans la prise en charge des asthmes modérés, et l'utilisation d'immunothérapies ciblées envers certains phénotypes d'asthme se répand. Les thérapies inhalées deviennent de plus en plus orientées vers la volonté du patient. Cet article précise les nouveautés dans la prise en charge de l'asthme à destination du praticien, notamment l'utilisation de bêta2-agonistes à courte durée d'action seuls qui n'ont plus leur place sans corticostéroïde inhalé.
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Asma/terapia , Atención Primaria de Salud , Administración por Inhalación , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Agonistas Adrenérgicos beta/administración & dosificación , Agonistas Adrenérgicos beta/uso terapéutico , Asma/tratamiento farmacológico , Humanos , InmunoterapiaRESUMEN
Polycyclic molecules featuring all-carbon quaternary bridgehead centers were synthesized through domino cyclizations between N-tosylhydrazones and boronic acids. Variations of the general cascade have been applied for the preparation of 3-quinuclidinones and related alkaloid-like scaffolds through transannular heterocyclizations. Moreover, the employment of 3-cyanopropyl and 4-cyanobutylboronic acids and α,ß-unsaturated N-tosylhydrazones led to spirocycles through unprecedented formal [n+1] cyclizations, including the stereoselective spirocyclization of the Hajos-Parrish ketone. The common feature of all the new reactions described is the creation of an all-carbon quaternary center by formation of two Csp3 -C bonds on the hydrazonic carbon atom. DFT-based calculations suggested the occurrence of cascade processes, which involve a diazo compound carboborylation followed by a 1,3-borotropic rearrangement on an intermediate allylboronic acid and a novel bora-aza-ene cyclization.
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Toxocariasis is a zoonotic disease that occurs when humans are infected by the parasites Toxocara canis or Toxocara cati. Toxocariasis is highly prevalent in tropical areas, but can also be found in industrialized countries, particularly in rural areas. Clinical presentation can range from asymptomatic infection to more severe disease. Diagnosis of toxocariasis is based on suggestive clinical findings, eosinophilia and a positive serological testing. Albendazole represents the first-line treatment, associated with corticosteroids in case of severe disease. Here we describe three clinical cases of toxocariasis in order to illustrate the clinical presentation, diagnosis and treatment of this unrecognized disease.
La toxocarose est une zoonose liée à l'infection de l'homme par Toxocara canis et Toxocara cati. Sa prévalence est élevée dans les zones tropicales, mais également dans les pays industrialisés, notamment dans les zones rurales. La plupart des formes sont asymptomatiques, se révélant par la présence d'une éosinophilie. Une dissémination, syndrome de larva migrans viscérale, et une atteinte oculaire, syndrome de larva migrans oculaire, sont les deux principaux syndromes. Le diagnostic de la toxocarose repose sur la présence d'une symptomatologie compatible, d'une éosinophilie et d'une sérologie positive. Le traitement de choix est l'albendazole, associé aux corticostéroïdes en cas d'atteinte sévère. Nous présentons trois cas de toxocarose, afin d'illustrer la présentation, le diagnostic et la prise en charge de cette infection méconnue.
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Enfermedades Desatendidas/diagnóstico , Toxocariasis/diagnóstico , Zoonosis/diagnóstico , Corticoesteroides/uso terapéutico , Adulto , Anciano , Albendazol/uso terapéutico , Animales , Eosinofilia/diagnóstico , Eosinofilia/parasitología , Femenino , Humanos , Persona de Mediana Edad , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/epidemiología , Prevalencia , Pruebas Serológicas , Suiza/epidemiología , Toxocara/aislamiento & purificación , Toxocariasis/tratamiento farmacológico , Toxocariasis/epidemiología , Zoonosis/tratamiento farmacológico , Zoonosis/parasitologíaRESUMEN
A novel strategy for the synthesis of functionalized carbocycles is defined, through the cascade carbocyclization of alkenylboronic acids with δ- or γ-cyano-N-tosylhydrazones. In the reaction, two C(sp(3))-C(sp(2)) bonds are formed on the former hydrazonic carbon generating an all-carbon quaternary stereocenter, and leading to cyclic ketones featuring an alkenyl side chain with complete diastereoselectivity. The processes are conducted under very simple experimental conditions, only in the presence of K2CO3, in 1,4-dioxane as solvent and under microwave irradiation, and have been applied for the synthesis of a wide structural variety of fused cyclopentanones and cyclohexanones. Moreover, the versatility of this methodology has been demonstrated in the structural modification of androsterone.
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The reactions between alkenylboronic acids and tosylhydrazones derived from substituted cyclohexanones lead to the construction of disubstituted cyclohexanes with total regio- and stereoselectivity. In these transition-metal-free processes, a Csp(3) -Csp(2) and Csp(3) -H bond are formed on the same carbon atom. The stereoselective reaction is general for 2-, 3-, and 4-substituted cyclohexanone tosylhydrazones, as well as for 2-substituted cyclopentanones. However, no stereoselectivity is observed for acyclic derivatives. DFT computational modeling suggests that the stereoselectivity of the reaction is determined by the approach of the boronic acid to the diazocyclohexane on its most stable chair conformation through an equatorial trajectory.
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The Pd-catalyzed reaction between 2,2'-dibromobiphenyls and related systems with tosylhydrazones gives rise to new π-extended conjugated polycarbo- and heterocycles through an autotandem process involving a cross-coupling reaction followed by an intramolecular Heck cyclization. The reaction shows wide scope regarding both coupling partners. Cyclic and acyclic tosylhydrazones can participate in the process. Additionally, a variety of aromatic and heteroaromatic dibromoderivatives have been employed, leading to an array of diverse scaffolds featuring a fluorene or acridine central nucleus, and containing binaphthyl, thiophene, benzothiophene and indole moieties. The application to appropriate tetrabrominated systems led to greater structural complexity through two consecutive autotandem cascades. The photophysical properties of selected compounds were studied through their absorption and emission spectra. Fluorescence molecules featuring very high quantum yields were identified, showing the potential of this methodology in the development of molecules with interesting optoelectronic properties.
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The reactions between terminal alkynes and α-chiral tosylhydrazones lead to the obtention of chiral pyrazoles with a stereogenic group directly attached at a nitrogen atom. The cascade reaction includes decomposition of the hydrazone into a diazocompound, 1,3-dipolar cycloaddition of the diazo compound with the alkyne, and [1,5]â sigmatropic rearrangement with migration of the stereogenic group. This strategy has been successfully applied to the synthesis of structurally diverse chiral pyrazoles through α-chiral tosylhydrazones, obtained from α-phenylpropionic acid, α-amino acids, and 2-methoxycyclohexanone. Notably, the stereoretention of the [1,5]â sigmatropic rearrangements represent very rare examples of this stereospecific transformation.
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Alquinos/química , Reacción de Cicloadición , Hidrazonas/química , Pirazoles/síntesis química , Estructura Molecular , Pirazoles/química , Teoría Cuántica , EstereoisomerismoRESUMEN
Objectives: Artificial intelligence tools such as Chat Generative Pre-trained Transformer (ChatGPT) have been used for many health care-related applications; however, there is a lack of research on their capabilities for evaluating morally and/or ethically complex medical decisions. The objective of this study was to assess the moral competence of ChatGPT. Materials and methods: This cross-sectional study was performed between May 2023 and July 2023 using scenarios from the Moral Competence Test (MCT). Numerical responses were collected from ChatGPT 3.5 and 4.0 to assess individual and overall stage scores, including C-index and overall moral stage preference. Descriptive analysis and 2-sided Student's t-test were used for all continuous data. Results: A total of 100 iterations of the MCT were performed and moral preference was found to be higher in the latter Kohlberg-derived arguments. ChatGPT 4.0 was found to have a higher overall moral stage preference (2.325 versus 1.755) when compared to ChatGPT 3.5. ChatGPT 4.0 was also found to have a statistically higher C-index score in comparison to ChatGPT 3.5 (29.03 ± 11.10 versus 19.32 ± 10.95, P =.0000275). Discussion: ChatGPT 3.5 and 4.0 trended towards higher moral preference for the latter stages of Kohlberg's theory for both dilemmas with C-indices suggesting medium moral competence. However, both models showed moderate variation in C-index scores indicating inconsistency and further training is recommended. Conclusion: ChatGPT demonstrates medium moral competence and can evaluate arguments based on Kohlberg's theory of moral development. These findings suggest that future revisions of ChatGPT and other large language models could assist physicians in the decision-making process when encountering complex ethical scenarios.
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OBJECTIVE: Impella 5.5 (Abiomed, Danvers, MA, USA) is approved by the US Food and Drug Administration (FDA) for mechanical circulatory support for ≤14 days. It is unknown whether prolonged support is associated with worse outcomes. We sought to review our single-center experience with Impella 5.5 and compare outcomes based on support duration. METHODS: We retrospectively reviewed adult patients (≥18 years old) supported with Impella 5.5 at our institution (May 2020 to April 2023). Patients on prolonged support (>14 days) were compared with those supported for ≤14 days. RESULTS: There were 31 patients supported with Impella 5.5 including 14 (45.2%) supported >14 days. Median support duration for those on prolonged support was 43.5 (interquartile range [IQR] 25 to 63.5) days versus 8 (IQR 6, 13) days for those who were not (P < 0.001). Overall, the device-related complication rate was 9.7% and did not differ between groups (P = 0.08). Overall, 30-day postimplant survival was 71% and did not differ by support duration (P = 0.2). In-hospital mortality was 32% and did not differ between cohorts (P > 0.99). Among those surviving to explant (n = 22), long-term strategy included bridge to durable ventricular assist device (18%, n = 4), cardiac transplant (55%, n = 12), and cardiac recovery (27%, n = 6). CONCLUSIONS: High-risk patients with cardiogenic shock may be supported with Impella 5.5 beyond the FDA-approved duration without increased risk of complications or mortality.
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Trasplante de Corazón , Corazón Auxiliar , Adulto , Estados Unidos/epidemiología , Humanos , Adolescente , Estudios Retrospectivos , United States Food and Drug Administration , Resultado del Tratamiento , Choque Cardiogénico/etiología , Corazón Auxiliar/efectos adversosRESUMEN
Herein, we present a synthetic procedure for the facile and general preparation of novel S-alkenyl and dienyl phosphoro(di)thioates for the first time. Extensive mechanistic investigations support that the reactions rely on a photochemical excitation of a halogen-bonding complex, formed with a phosphorothioate salt and an alkenyl or dienyl bromide, which light-induced fragmentation leads to the formation of the desired products through a radical-based pathway. The substrate scope is broad and exhibits a wide functional group tolerance in the formation of the final compounds, including molecules derived from natural products, all with unknown and potentially interesting biological properties. Eventually, a very efficient continuous flow protocol was developed for the upscale of these reactions.
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The synthesis of benzylboronates by photochemical homologation of boronic acids with N-tosylhydrazones under basic conditions is described. The reaction involves the photolysis of the N-tosylhydrazone salt to give a diazoalkane followed by the geminal carboborylation of the diazoalkane. Under the mild reaction conditions, the protodeboronation of the unstable benzylboronic acid is circumvented and the pinacolboronates can be isolated after reaction of the benzylboronic acid with pinacol. The metholodogy has been applied to the reactions of alkylboronic acids with N-tosylhydrazones of aromatic aldehydes and ketones, and to the reactions of arylboronic acids with N-tosylhydrazones of aliphatic ketones. Moreover, the employment of the DBU/DIPEA bases combination allows for homogeneous reactions which have been adapted to photochemical continuous flow conditions. Additionally, the synthetic versatility of boronates enables their further transformation via Csp3-C or Csp3-X bond forming reactions converting this methodology into a novel method for the geminal difunctionalization of carbonyls via N-tosylhydrazones.
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The discovery of new activation modes for the creation of carbon-centered radicals is a task of great interest in organic chemistry. Classical activation modes for the generation of highly reactive radical carbon-centered intermediates typically relied on thermal activation of radical initiators or irradiation with unsafe energetic UV light of adequate reaction precursors. In recent years, photoredox chemistry has emerged as a leading strategy towards the catalytic generation of C-centered radicals, which enabled their participation in novel synthetic organic transformations which is otherwise very challenging or even impossible to take place. As an alternative to these activation modes for the generation of C-centered radicals, the pursuit of greener, visible-light initiated reactions that do not necessitate a photoredox/metal catalyst has recently caught the attention of chemists. In this review, we covered recent transformations, which rely on photoactivation with low-energy light of a class of EDA complexes, known as halogen-bonding adducts, for the creation of C-centered radicals.
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Coronary microvascular dysfunction is an underdiagnosed pathologic process that is associated with adverse clinical outcomes. Biomarkers, molecules measurable in the blood, could inform the clinician by aiding in the diagnosis and management of coronary microvascular dysfunction. We present an updated review of circulating biomarkers in coronary microvascular dysfunction representing key pathologic processes, including inflammation, endothelial dysfunction, oxidative stress, coagulation, and other mechanisms.
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Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Humanos , Biomarcadores , Inflamación , Estrés Oxidativo , Vasos Coronarios/diagnóstico por imagenRESUMEN
This article studies the release of phenolic compounds during cocoa heating under vacuum, N2, and air atmospheres, and proposes fast heating (60 °C ⢠s-1) as a methodology that allows the release of polyphenols from fermented cocoa powder. We aim to demonstrate that gas phase transport is not the only mechanism to extract compounds of interest and that convective-type mechanisms can facilitate the process by reducing their degradation. The oxidation and transport phenomena were evaluated both in the extracted fluid and in the solid sample during the heating process. Polyphenols transport phenomena were assessed based on the fluid (chemical condensate compounds) that was collected cold with an organic solvent (methanol) in a hot plate reactor. Out of all the polyphenolic compounds present in cocoa powder, we assessed specifically the release of catechin and epicatechin. We found that high heating rates combined with vacuum or N2 favor the ejection of liquids; then, it is possible to extract compounds such as catechin-which is dissolved/entrained and transported in the ejected liquids-and avoid degradation phenomena.
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Catequina , Chocolate , Calefacción , Fenoles , PolifenolesRESUMEN
Introduction: Optimal anticoagulation therapy is essential for the prevention of thrombotic and hemorrhagic complications in pediatric patients supported with extracorporeal membrane oxygenation (ECMO). Recent data have demonstrated bivalirudin has the potential to surpass and replace heparin as the anticoagulant of choice. Methods: We conducted a systematic review comparing the outcomes of heparin-based versus bivalirudin-based anticoagulation in pediatric patients supported on ECMO to identify the preferred anticoagulant to minimize bleeding events, thrombotic complications, and associated mortality. We referenced the PubMed, Cochrane Library, and Embase databases. These databases were searched from inception through October 2022. Our initial search identified 422 studies. All records were screened by two independent reviewers using the Covidence software for adherence to our inclusion criteria, and seven retrospective cohort studies were identified as appropriate for inclusion. Results: In total, 196 pediatric patients were anticoagulated with heparin and 117 were anticoagulated with bivalirudin while on ECMO. Across the included studies, it was found that for patients treated with bivalirudin, trends were noted toward lower rates of bleeding, transfusion requirements, and thrombosis with no difference in mortality. Overall costs associated with bivalirudin therapy were lower. Time to therapeutic anticoagulation varied between studies though institutions had different anticoagulation targets. Conclusion: Bivalirudin may be a safe, cost-effective alternative to heparin in achieving anticoagulation in pediatric ECMO patients. Prospective multicenter studies and randomized control trials with standard anticoagulation targets are needed to accurately compare outcomes associated with heparin versus bivalirudin in pediatric ECMO patients.
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The coronary microvasculature is responsible for providing oxygen and nutrients to myocardial tissue. A healthy microvasculature with an intact and properly functioning endothelium accomplishes this by seemless changes in vascular tone to match supply and demand. Perturbations in the normal physiology of the microvasculature, including endothelial and/or vascular smooth muscle dysfunction, result in impaired function (vasoconstriction, antithrombotic, etc.) and structural (hypertrophic, fibrotic) abnormalities that lead to microvascular ischemia and potential organ damage. While coronary microvascular dysfunction (CMD) is the primary pathologic driving force in ischemia with non-obstructive coronary artery disease (INOCA), angina with no obstructive coronary arteries (ANOCA), and myocardial infarction with non-obstructed coronary arteries (MINOCA), it may be a bystander in many cardiac disorders which later become pathologically associated with signs and/or symptoms of myocardial ischemia. Importantly, regardless of the primary or secondary basis of CMD in the heart, it is associated with important increases in morbidity and mortality. In this review we discuss salient features pertaining to known pathophysiologic mechanisms driving CMD, the spectrum of heart diseases where it places a critical role, invasive and non-invasive diagnostic testing, management strategies, and the gaps in knowledge where future research efforts are needed.