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1.
RSC Adv ; 13(9): 5753-5761, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816081

RESUMO

We report a detailed study on the magnetic behaviors and magnetocaloric (MC) effect of a single crystal of lithium samarium tetraphosphate, LiSm(PO3)4. The analyses of temperature-dependent magnetization data have revealed magnetic ordering established with decreasing temperature below T p, where T p is the minimum of a dM/dT vs. T curve and varies as a linear function of the applied field H. The Curie temperature has been extrapolated from T p(H) data, as H → 0, to be about 0.51 K. The establishment of magnetic-ordering causes a substantial change in the heat capacity C p. Above T p, the crystal exhibits paramagnetic behavior. Using the Curie-Weiss (CW) law and Arrott plots, we have found the crystal to have a CW temperature θ CW ≈ -36 K, and short-range magnetic order associated with a coexistence of antiferromagnetic and ferromagnetic interactions ascribed to the couplings of magnetic dipoles and octupoles at the Γ7 and Γ8 states. An assessment of the MC effect has shown increases in value of the absolute magnetic-entropy change (|ΔS m|) and adiabatic-temperature change (ΔT ad) when lowering the temperature to 2 K, and increasing the magnetic-field H magnitude. Around 2 K, the maximum value of |ΔS m| is about 3.6 J kg-1 K-1 for the field H = 50 kOe, and ΔT ad is about 5.8 K for H = 20 kOe, with the relative cooling power (RCP) of ∼82.5 J kg-1. In spite of a low MC effect in comparison to Li(Gd,Tb,Ho)(PO3)4, the absence of magnetic hysteresis reflects that LiSm(PO3)4 is also a candidate for low-temperature MC applications below 25 K.

2.
Org Lett ; 24(31): 5746-5750, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35905441

RESUMO

Herein we report the use of indoles, one of the most common nitrogen-containing heterocycles in FDA-approved drugs, as nucleophiles in the Pd-catalyzed aza-Wacker reaction. This N-functionalization of indoles is a Markovnikov selective olefin functionalization of simple alkenes using catalytic Pd(NPhth)2(PhCN)2 and O2 as the terminal oxidant in the presence of catalytic Bu4NBr. Various substituted indoles and alkenes are found to participate; 21 examples are presented with yields ranging from 41 to 97% isolated yield. Additionally, lactams and oxazolidinones are shown to participate under the reaction conditions. Mechanistic investigations suggest that the phthalimide ligand and Bu4NBr additive slow undesired side reactions: indole decomposition and olefin isomerization, respectively.


Assuntos
Alcenos , Paládio , Aminação , Catálise , Indóis , Estrutura Molecular , Estresse Oxidativo
3.
Eur Rev Med Pharmacol Sci ; 26(3): 879-887, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35179753

RESUMO

OBJECTIVE: Our objective is to identify the prevalence of depression among inpatients with heart failure (HF), and to ascertain the factors associated with the depression from a wide spectrum of sociodemographic variables. MATERIALS AND METHODS: We conducted a hospital-based cross-sectional survey of prospectively collected data in inpatients with a diagnosis of HF at Vietnam National Heart Institute, Bach Mai Hospital (Hanoi, Vietnam) from July 2020 to July 2021. A sample size of 128 inpatients with HF was finally included. Primary outcome variable was depression ICD-10. RESULTS: The mean age was 62.34 (SD = 14.76). The sex ratio was 66 males to 62 females. The overall prevalence of depression ICD-10 was 46.88% among HF inpatients. The proportion of the depressed patients fluctuated between 37.21% and 83.33% by NYHA heart failure classification. Compared to the depressive prevalence among patients with NYHA class II, the odds were 8.43 times higher for those with NYHA class IV (OR univariate 8.43; 95% CI 1.63-43.46). Patient's age was significantly associated with increased prevalence of depression (OR multivariate 1.07; 95% CI 1.003-1.14). It was significantly higher odds of depression in HF patients who felt sadness after a diagnosis of an illness (OR multivariate 18.02, 95% CI: 4.21-77.08). Individuals with higher household economic status were less likely to be diagnosed with depression compared to those with lower household economic status (OR multivariate 0.15, 95% CI: 0.02-0.92). The odds of depression were significantly higher in HF patients who reported family conflict (OR multivariate 23.45, 95% CI: 1.29-423.55), and in those having the loss of a close family member (OR multivariate 38.62, 95% CI: 1.41-1055.98). CONCLUSIONS:   The prevalence of depression by ICD-10 was relatively high. Age of patient, sadness after a diagnosis of an illness, household economic status, family conflict and loss of a close family member were significantly associated with the depression among HF inpatients. Present results suggest a need for a disease management program addressing both psychological and HF aspects with the aim of improving health outcomes for the inpatients in Vietnam health facilities.


Assuntos
Insuficiência Cardíaca , Pacientes Internados , Estudos Transversais , Depressão/psicologia , Feminino , Instalações de Saúde , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Humanos , Pacientes Internados/psicologia , Masculino , Pessoa de Meia-Idade , Prevalência , Vietnã/epidemiologia
5.
Eur J Clin Pharmacol ; 36(4): 395-400, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2737233

RESUMO

The plasma and urine pharmacokinetic parameters of pyrazinamide and of its metabolites (pyrazinoic acid, 5-hydroxy-pyrazinamide, 5-hydroxy-pyrazinoic acid and pyrazinuric acid) have been studied after a single oral dose of pyrazinamide 27 mg.kg-1 in 9 healthy subjects. Pyrazinamide was rapidly absorbed (tmax less than or equal to 1 h) and showed a short distribution phase followed by an elimination phase of t1/2 beta = 9.6 h. The close similarity of the apparent elimination rates of the metabolites led to a second trial of a single oral dose of pyrazinoic acid to evaluate the formation and elimination stages. The limiting factor was found to be the activity of a microsomal deamidase (pyrazinoic acid formation from pyrazinamide and 5-hydroxy-pyrazinoic acid formation from 5-hydroxy-pyrazinamide). In contrast, oxidation by xanthine oxidase occurred very rapidly (5-hydroxy-pyrazinamide formation and pyrazinoic acid catabolism to 5-hydroxy-pyrazinoic acid).


Assuntos
Pirazinamida/farmacocinética , Cromatografia Líquida de Alta Pressão , Meia-Vida , Humanos , Masculino , Pirazinamida/análogos & derivados
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