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1.
Int J Mol Sci ; 25(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38673991

RESUMO

This review examines the impact of obesity on the pathophysiology of heart failure with preserved ejection fraction (HFpEF) and focuses on novel mechanisms for HFpEF prevention using a glucagon-like peptide-1 receptor agonism (GLP-1 RA). Obesity can lead to HFpEF through various mechanisms, including low-grade systemic inflammation, adipocyte dysfunction, accumulation of visceral adipose tissue, and increased pericardial/epicardial adipose tissue (contributing to an increase in myocardial fat content and interstitial fibrosis). Glucagon-like peptide 1 (GLP-1) is an incretin hormone that is released from the enteroendocrine L-cells in the gut. GLP-1 reduces blood glucose levels by stimulating insulin synthesis, suppressing islet α-cell function, and promoting the proliferation and differentiation of ß-cells. GLP-1 regulates gastric emptying and appetite, and GLP-1 RA is currently indicated for treating type 2 diabetes (T2D), obesity, and metabolic syndrome (MS). Recent evidence indicates that GLP-1 RA may play a significant role in preventing HFpEF in patients with obesity, MS, or obese T2D. This effect may be due to activating cardioprotective mechanisms (the endogenous counter-regulatory renin angiotensin system and the AMPK/mTOR pathway) and by inhibiting deleterious remodeling mechanisms (the PKA/RhoA/ROCK pathway, aldosterone levels, and microinflammation). However, there is still a need for further research to validate the impact of these mechanisms on humans.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Insuficiência Cardíaca , Síndrome Metabólica , Volume Sistólico , Humanos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Síndrome Metabólica/metabolismo , Síndrome Metabólica/tratamento farmacológico , Volume Sistólico/efeitos dos fármacos , Animais , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Obesidade/metabolismo , Obesidade/complicações , Obesidade/tratamento farmacológico
2.
Org Biomol Chem ; 22(10): 1993-1997, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38372038

RESUMO

A solventless and acid-catalyzed condensation of meso-perfluoroalkyl-dipyrromethanes with selected benzaldehydes was used to prepare ten different bilanes that were isolated before their oxidation into trans-A2B-corroles bearing two meso-perfluoroalkyl groups. Macrocycles bearing long chains (C3F7 or C7F15) are key precursors to afford ABC-corroles having a meso-acyl substituent when subjected to a mild and basic hydrolysis affecting one of the alkyl substituents.

3.
ARS med. (Santiago, En línea) ; 48(4): 54-60, dic. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1527569

RESUMO

Introduction: ameloblastomas correspond to one of the most prevalent odontogenic tumors in developing countries, they are mainly located in the mandible, and their treatment has been widely discussed over the years, using radical or conservative treatments depending on different variables. Clinical case: we present two cases of patients with ameloblastoma who underwent conservative treatment without the use of adjuvant therapy, obtaining satisfactory results at 36 and 48 months. Discussion: due to a possible recurrence with conservative treatment, radical management has been suggested, however, the choice of treatment should be based on a series of clinical, histological, and radiographic characteristics.


Introducción: Los ameloblastomas corresponden a uno de los tumores odontogénicos más prevalentes en los países en desarrollo, se ubican principalmente en la mandíbula, y su tratamiento ha sido ampliamente discutido a lo largo de los años, utilizando tratamientos radicales o conservadores dependiendo de distintas variables. Caso clínico: se presentan dos casos de pacientes con un ameloblastoma a quienes se les realizó tratamiento conservador sin uso de terapia coadyuvante, obteniendo resultados satisfactorios a los 36 y 48 meses. Discusión: Debido a una posible recurrencia con un tratamiento conservador, se ha sugerido manejo radical, sin embargo, la elección de tratamiento debe ser en base a una serie de características clínicas, histológicas y radiográficas.

4.
Chemistry ; 29(25): e202203175, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36602462

RESUMO

Non-covalent hybrid materials based on graphene and A3 -type copper corrole complexes were computationally investigated. The corroles complexes contain strong electron-withdrawing fluorinated substituents at the meso positions. Our results show that the non-innocent character of corrole moiety modulates the structural, electronic, and magnetic properties once the hybrid systems are held. The graphene-corrole hybrids displayed outstanding stability via the interplay of dispersion and electrostatic driving forces, while graphene act as an electron reservoir. The hybrid structures exposed an intriguing magneto-chemical performance, compared to the isolated counterparts, that evidenced how structural and electronic effects contributed to the magnetic response for both ferromagnetic and antiferromagnetic cases. Directional spin polarization and spin transfer from the corrole to the graphene surface participate in the amplification. Finally, there are relations between the spin transfer, the magnetic response, and the copper distorted ligand field, offering exciting hints about modulating the magnetic response. Therefore, this work shows that copper corroles emerged as versatile building blocks for graphene hybrid materials, especially in applications requiring a magnetic response.

5.
Phys Chem Chem Phys ; 18(2): 726-34, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26449274

RESUMO

A family of cyclometalated Ir(III) complexes was studied through quantum chemistry calculations to get insights into their applicability in light electrochemical cells (LECs). The complexes are described as [Ir(R-C^N)2(ppl)](+), where ppl is the pyrazino[2,3-f][1,10]-phenanthroline ancillary ligand. The modification of the HOMO energy in all the complexes was achieved by means of different R-C^N cyclometalating ligands, with R-ppy (phenylpyridine), R-pyz (1-phenylpyrazole) or R-pypy (2,3'-bipyridine); in addition, inductive effects were taken into account by substitution with the R groups (R = H, F or CF3). Then, compounds with HOMO-LUMO energy gaps from 2.76 to 3.54 eV were obtained, in addition to emission energies in the range of 438 to 597 nm. The emission deactivation pathways confirm the presence of metal-to-ligand transitions in all the complexes, which allow the strong spin-orbit coupling effects, and then improving the luminescence performance. However, the coupling with ligand and metal centered excited states was observed for the blue-shifted emitters, which could result in a decrease of the luminescence efficiencies. Furthermore, ionization potentials, electron affinities and reorganization energies (for holes and electrons) were obtained to account for the injection and transport properties of all the complexes in electroluminescent devices.

6.
J Phys Chem B ; 119(41): 13208-17, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26398329

RESUMO

Photochromic solid materials based on the cationic polymer poly(decylviologen) are reported. The solids were obtained by freeze-drying colloidal suspensions of nanocomplexes obtained by mixing aqueous solutions of the polycation with different solutions of polyanions such as poly(sodium 4-styrenesulfonate) or sodium alginate, at a cationic/anionic polymeric charge ratio of 0.7. The photochromic responses of the solid materials fabricated with alginate as complementary charged polyelectrolyte of the cationic polyviologen are faster than those of the solid materials fabricated with poly(sodium 4-styrenesulfonate), achieving coloration kinetics in the order of minutes, and discoloration kinetics in the order of hours for the former. Aromatic-aromatic interactions between the latter polyanion and the polyviologen may stabilize the dicationic form of the viologen derivative, increasing the necessary energy to undergo photoreduction, thus decreasing the reduction kinetics.


Assuntos
Alginatos/química , Polímeros/química , Ácidos Sulfônicos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Microscopia Eletrônica de Transmissão e Varredura , Espectroscopia de Prótons por Ressonância Magnética
7.
J Phys Chem A ; 119(26): 6909-18, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26061641

RESUMO

The interaction of arsenic(III) onto the tetrahedral Au20 cluster was studied computationally to get insights into the interaction of arsenic traces (presented in polluted waters) onto embedded electrodes with gold nanostructures. Pollutant interactions onto the vertex, edge, or inner gold atoms of Au20 were observed to have a covalent character by forming metal-arsenic or metal-oxygen bonding, with adsorption energies ranging from 0.5 to 0.8 eV, even with a stable physisorption; however, in aqueous media, the Au-vertex-pollutant interaction was found to be disadvantageous. The substituent effect of a platinum atom onto the Au20 cluster was evaluated to get insights into the changes in the adsorption and electronic properties of the adsorbent-adsorbate systems due to chemical doping. It was found that the dopant atom increases both the metal-pollutant adsorption energy and stability onto the support in a water media for all interaction modes; adsorption energies were found to be in a range of 0.6 to 1.8 eV. All interactions were determined to be accompanied by electron transfer as well as changes in the local reactivity that determine the amount of transferred charge and a decrease in the HOMO-LUMO energy gap with respect to the isolated substrate.


Assuntos
Arsênio/química , Ouro/química , Platina/química , Adsorção , Simulação por Computador , Monitoramento Ambiental , Ligação de Hidrogênio , Modelos Químicos , Estrutura Molecular , Solventes/química , Água/química , Poluentes Químicos da Água/química
8.
Rev Med Chil ; 142(8): 1065-8, 2014 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-25424680

RESUMO

Constrictive Pericarditis (CP) is an unusual disease. Its most common causes are idiopathic or secondary to cardiac surgery. Less frequently it is caused by connective tissue diseases. We report a 30 years old woman hospitalized due to progressive dyspnea, chest pain and signs of right sided heart failure. During her stay, a Systemic Lupus Erythematosus (SLE) was diagnosed. The echocardiogram suggested a CP and the diagnosis was confirmed by cardiac catheterization. Pericardiectomy was successfully performed. The biopsy confirmed a nonspecific chronic pericarditis, with extensive fibrosis and absence of caseating granulomas. The patient had a satisfactory recovery.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Pericardite Constritiva/etiologia , Adulto , Cateterismo Cardíaco , Doença Crônica , Feminino , Humanos , Pericardiectomia , Pericardite Constritiva/diagnóstico
9.
Rev. méd. Chile ; 142(8): 1065-1068, ago. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-728354

RESUMO

Constrictive Pericarditis (CP) is an unusual disease. Its most common causes are idiopathic or secondary to cardiac surgery. Less frequently it is caused by connective tissue diseases. We report a 30 years old woman hospitalized due to progressive dyspnea, chest pain and signs of right sided heart failure. During her stay, a Systemic Lupus Erythematosus (SLE) was diagnosed. The echocardiogram suggested a CP and the diagnosis was confirmed by cardiac catheterization. Pericardiectomy was successfully performed. The biopsy confirmed a nonspecific chronic pericarditis, with extensive fibrosis and absence of caseating granulomas. The patient had a satisfactory recovery.


Assuntos
Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Pericardite Constritiva/etiologia , Cateterismo Cardíaco , Doença Crônica , Pericardiectomia , Pericardite Constritiva/diagnóstico
10.
J Mol Model ; 19(9): 3569-80, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23722557

RESUMO

The physisorption of bisphenol A (BPA) on pristine and oxidized graphene was studied theoretically via calculations performed at the PBE-D3 level (including dispersion force corrections). Three stable conformations of BPA on graphene were found. A lying-down configuration was energetically favored because the presence of π-π stacking and dispersion forces increased interactions. In addition, the adsorption of BPA on the edges of graphene oxide was enhanced when adsorption occurred on carboxyl and carbonyl groups, whereas the adsorption strength decreased when adsorption occurred on hydroxyl groups. The highest physisorption strength was obtained on the surface of graphene oxide due to the presence of π-π stacking and dispersion forces (which provided the greatest contribution to the adsorption energy) as well as hydrogen bonds (which provided a smaller contribution), indicating that oxidized graphene is a better candidate than pristine graphene for BPA removal. On the other hand, an increase in electrophilicity was observed after the physisorption of BPA in all systems (with respect to graphene and BPA in their isolated forms), with the adsorbent acting as the electron acceptor. Finally, molecular dynamics simulations performed using the PM6 Hamiltonian showed that the adsorption of BPA on graphene is stable.


Assuntos
Compostos Benzidrílicos/química , Grafite/química , Modelos Moleculares , Óxidos/química , Fenóis/química , Adsorção , Conformação Molecular
12.
Rev. chil. neurocir ; 1(2): 123-30, ago. 1987. tab
Artigo em Espanhol | LILACS | ID: lil-58912

RESUMO

Se analizan 103 pacientes egresados del Servicio de Neurocirugía del Hospital Guillermo Grant Benavente de Concepción, en el período 1980-1985. El egreso anual promedio fue de 17 casos. El 70% fue de sexo femenino. La mayor incidencia se observó entre los 40-59 años (55.3%). El 67% (69 casos) ingresan durante las primeras 72 horas post H.S.A.. El 70% (72 casos) ingresan en grado 1 y 2 de escala de BOTTERELL. La ubicación topográfica de los aneurismas fue: CI. 57 casos (55.4%); CM. 29 casos (28.1%) y C. Anterior-Comunicante anterior 17 casos (16.5%). En el 82% (85 casos) no se describe vaso espasmo. Las complicaciones post angiográfica fueron 11 casos (10.6%) e incluye dos fallecimientos. La TAC. de Cerebro se realizó desde 1982 en 47 enfermos (45% casos) y su hallazgo más frecuente fue la Hemocisterna (25 casos) 53%. El 52.8% se operan en la 2-3 semana. Sólo el 4.4% (3 casos), se interviene en los primeros 7 días. Del total de la serie, fallecen 16 casos sin cirugía (15,5%); la causa más importante fue el resangramiento. De los 103 casos, 19 pacientes no se practica cirugía (18.4%). Del total de casos, 68 casos son operados. 36 corresponden a la CI: 21 a la CM. y 8 casos complejo cerebral anterior comunicante anterior. Hay que agregar 2 casos de aneurismas múltiples y un caso de aneurisma gigante silviano izquierdo. La mortalidad post-cirugía fue 10.2% (7 casos). Los resultados tardíos (6 meses- 6 años) en 50 casos destaca 24 casos (39.3%) con resultados excelentes. Deben agregarse 11 casos sin control posterior en el policlínico (18%)


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Aneurisma Intracraniano
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