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1.
Cureus ; 15(7): e42063, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37602083

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can affect multiple organs due to activation of an inflammatory response. One of the key components of this response is the activation of immunoglobulin A (IgA), thus causing endothelial injury and inflammation. Henoch-Schönlein purpura (HSP) has been rarely reported in adult patients as a complication of the coronavirus disease 2019 (COVID-19) infection. In this report, we present a case of HSP occurring one week after the diagnosis of COVID-19 in a 23-year-old woman. Her symptoms included nausea, vomiting, diffused abdominal pain, joint pain, hematuria, and palpable purpura of the lower extremities. She was treated with intravenous methylprednisolone sodium succinate, followed by oral prednisone therapy, which resulted in clinical improvement, including resolution of abdominal and joint pain as well as skin rashes, without remaining renal complication.

2.
J Agric Food Chem ; 71(14): 5770-5782, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36977192

RESUMO

GCR1 has been proposed as a plant analogue to animal G-protein-coupled receptors that can promote or regulate several physiological processes by binding different phytohormones. For instance, abscisic acid (ABA) and gibberellin A1 (GA1) have been shown to promote or regulate germination and flowering, root elongation, dormancy, and biotic and abiotic stresses, among others. They may act through binding to GCR1, which would put GCR1 at the heart of key signaling processes of agronomic importance. Unfortunately, this GPCR function has yet to be fully validated due to the lack of an X-ray or cryo-EM 3D atomistic structure for GCR1. Here, we used the primary sequence data from Arabidopsis thaliana and the GEnSeMBLE complete sampling method to examine 13 trillion possible packings of the 7 transmembrane helical domains corresponding to GCR1 to downselect an ensemble of 25 configurations likely to be accessible to the binding of ABA or GA1. We then predicted the best binding sites and energies for both phytohormones to the best GCR1 configurations. To provide the basis for the experimental validation of our predicted ligand-GCR1 structures, we identify several mutations that should improve or weaken the interactions. Such validations could help establish the physiological role of GCR1 in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais/fisiologia , Receptores Acoplados a Proteínas G/metabolismo
3.
Front Plant Sci ; 13: 992663, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311093

RESUMO

The OMICAS alliance is part of the Colombian government's Scientific Ecosystem, established between 2017-2018 to promote world-class research, technological advancement and improved competency of higher education across the nation. Since the program's kick-off, OMICAS has focused on consolidating and validating a multi-scale, multi-institutional, multi-disciplinary strategy and infrastructure to advance discoveries in plant science and the development of new technological solutions for improving agricultural productivity and sustainability. The strategy and methods described in this article, involve the characterization of different crop models, using high-throughput, real-time phenotyping technologies as well as experimental tissue characterization at different levels of the omics hierarchy and under contrasting conditions, to elucidate epigenome-, genome-, proteome- and metabolome-phenome relationships. The massive data sets are used to derive in-silico models, methods and tools to discover complex underlying structure-function associations, which are then carried over to the production of new germplasm with improved agricultural traits. Here, we describe OMICAS' R&D trans-disciplinary multi-project architecture, explain the overall strategy and methods for crop-breeding, recent progress and results, and the overarching challenges that lay ahead in the field.

4.
Phys Chem Chem Phys ; 24(35): 21250-21260, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36040431

RESUMO

Efficient strategies that allow the preparation of molecular systems in particular vibrational states are important in the application of quantum control schemes to chemical reactions. In this paper, we propose the preparation of quasi-bound vibrational states of the collinear transition state complex BrHBr, from vibrational states of the bihalide ion BrHBr-, that favor the bond selective breakage of BrHBr. The results shown complement the investigation that we reported in a previous paper, [A. J. Garzón-Ramírez, J. G. López and C. A. Arango, Int. J. Quantum Chem., 2018, 24, e25784], in which we demonstrated the feasibility of controlling the bond selective decomposition of the collinear BrHBr using linear combinations of reactive resonances. We employed a dipole moment surface, calculated at the QCISD/d-aug-cc-pVTZ level of theory, to simulate the interaction of the BrHBr- ground vibrational state with heuristically optimized sequences of ultrashort infrared linear chirped laser pulses to achieve a target vibrational state, resulting from expanding a chosen linear combination of reactive resonances of BrHBr in terms of vibrational eigenstates of BrHBr-. The results of our simulations show final states that capture the most relevant features of the target state with different levels of description depending on the sequence of laser pulses employed. We also discuss ways of improving the description of the target state and possible limitations of our approach.

5.
Cureus ; 14(6): e26293, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35898386

RESUMO

A pneumothorax is a pathological collection of air in the pleural space within the thoracic cavity. Pneumothoraxes are classified by the underlying etiology as spontaneous or traumatic, with spontaneous pneumothoraxes being further categorized into primary and secondary causes. Management historically involved admission with possible administration of oxygen or chest tube placements based on severity. We herein describe a pediatric -case of a likely blunt-force traumatic pneumothorax after a fall, successfully managed conservatively in the outpatient setting. The case highlights an acceleration-deceleration blunt trauma caused during a tackle at a football game and the importance of the clinical presentation, physical exam, and confirmation with a chest X-ray.

6.
Rev. colomb. cardiol ; 29(1): 111-114, ene.-feb. 2022. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1376863

RESUMO

Resumen Se presenta el caso de una paciente con atrapamiento de guía al interior del seno coronario durante el procedimiento de cambio de un electrodo (Sentus ProMRI OTW BP L-85) por desalojo asociado a disfunción de la terapia de resincronización cardiaca. Durante el implante del nuevo electrodo se presentó atrapamiento y retención intravascular de la guía utilizada para su posicionamiento a nivel del seno coronario, lo cual hizo imposible su remoción. La paciente no aceptó tratamiento quirúrgico, se encuentra en vigilancia médica y permanece asintomática desde hace 3 años.


Abstract It is reported the case of a patient with guidewire trapping inside the coronary sinus during an electrode exchange procedure (Sentus ProMRI OTW BP L-85) due to dislocation associated with dysfunction of cardiac re-synchronization therapy. During the implantation of the new electrode, entrapment of the guidewire used for its positioning at the level of the coronary sinus and intravascular retention were presented, making it impossible to remove it. The patient did not accept surgical treatment and has been under medical surveillance, asymptomatic for three years.

8.
Molecules ; 26(8)2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919518

RESUMO

There is ongoing interest in the alcohol industry to significantly reduce and/or add value to the liquid residue, vinasse, produced after the distillation and rectification of ethanol from sugar cane. Vinasse contains potassium, glycerol, and a protein component that can cause environmental issues if improperly disposed of. Currently, some industries have optimized their processes to reduce waste, and a significant proportion of vinasse is being considered for use as an additive in other industrial processes. In the manufacture of cement and asphalt, vinasse has been used in the mixtures at low concentrations, albeit with some physical and mechanical problems. This work is the first molecular approximation of the components of the sugar cane vinasse in an industrial context, and it provides atomic details of complex molecular events. In the current study, the major components of sugar cane vinasse, alone or complexed on the surface of calcium carbonate, were modeled and simulated using molecular dynamics. The results showed that the protein component, represented by the mannoprotein Mp1p, has a high affinity for forming hydrogen bonds with potassium and glycerol in the vinasse. Additionally, it provides atomic stability to the calcium carbonate surface, preserving the calcite crystalline structure in the same way potassium ions interact with the carbonate group through ion-dipole interactions to improve the cohesion of the modeled surface. On the contrary, when the glycerol molecule interacts with calcium carbonate using more than two hydrogen bonds, it triggers the breakdown of the crystalline structure of calcite expanding the ionic pair.


Assuntos
Carbonato de Cálcio/química , Resíduos Industriais , Saccharum/química , Solo/química , Etanol/química , Fertilizantes/análise , Simulação de Dinâmica Molecular
10.
J Chem Phys ; 149(24): 244110, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30599711

RESUMO

We proposed a methodology that allows to maximize the population transfer from a high vibrational state of the a 3Σ+ triplet state to the vibrational ground state of the X 1Σ+ singlet state though the optimization of one pump and one dump laser pulses. The pump pulse is optimized using a fitness function, heuristically improved, that includes the effect of the spin-orbit coupling of the KRb [b-A]-scheme. The dump pulse is optimized to maximize the population transfer to the ground state. We performed a comparison with the case in which the pump and dump pulses are optimized to maximize the population transfer to the ground state employing a genetic algorithm with a single fitness function. The heuristic approach turned out to be 70% more efficient than a quantum optimal control optimization employing a single fitness function. The method proposed provides simple pulses that have an experimental realm.

11.
J Fam Pract ; 66(10): 598-606, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28991936

RESUMO

Some share features, making them difficult to distinguish. Others may not be on your radar. Here we review 8 you're likely to see or need to exclude.


Assuntos
Medicina de Família e Comunidade/métodos , Viroses/diagnóstico , Viroses/terapia , Criança , Pré-Escolar , Terapia Combinada , Diagnóstico Diferencial , Humanos , Lactente , Vacinas , Viroses/prevenção & controle
12.
J Phys Chem B ; 120(15): 3754-64, 2016 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-26938052

RESUMO

Although hydrogels have been widely investigated for their use in materials science, nanotechnology, and novel pharmaceuticals, mechanistic details explaining their water-absorbent features are not well understood. We performed an all-atom molecular dynamics study of the structural transformation of chitosan nanohydrogels due to water absorption. We analyzed the conformation of dry, nanoscaled chitosan, the structural modifications that emerge during the process of water inclusion, and the dynamics of this biopolymer in the presence of nature's solvent. Two sets of nanoscaled, single-chained chitosan models were simulated: one to study the swelling dependence upon the degree of self-cross-linking and other to observe the response with respect to the degree of protonation. We verified that nanohydrogels keep their ability to absorb water and grow, regardless of their degree of cross-linking. Noteworthy, we found that the swelling behavior of nanoscaled chitosan is pH-dependent, and it is considerably more limited than that of larger scale hydrogels. Thus, our study suggests that properties of nanohydrogels are significantly different from those of larger hydrogels. These findings might be important in the design of novel controlled-release and targeted drug-delivery systems based on chitosan.


Assuntos
Quitosana/química , Simulação de Dinâmica Molecular , Nanopartículas/química , Água/química , Sistemas de Liberação de Medicamentos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio
13.
J Chem Phys ; 143(12): 124108, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26428997

RESUMO

We propose a methodology to design optimal pulses for achieving quantum optimal control on molecular systems. Our approach constrains pulse shapes to linear combinations of a fixed number of experimentally relevant pulse functions. Quantum optimal control is obtained by maximizing a multi-target fitness function using genetic algorithms. As a first application of the methodology, we generated an optimal pulse that successfully maximized the yield on a selected dissociation channel of a diatomic molecule. Our pulse is obtained as a linear combination of linearly chirped pulse functions. Data recorded along the evolution of the genetic algorithm contained important information regarding the interplay between radiative and diabatic processes. We performed a principal component analysis on these data to retrieve the most relevant processes along the optimal path. Our proposed methodology could be useful for performing quantum optimal control on more complex systems by employing a wider variety of pulse shape functions.

14.
J Chem Phys ; 138(7): 071104, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23444989

RESUMO

We computationally demonstrate the one-photon phase control of retinal isomerization under conditions of low laser intensity. The calculations, utilizing the multiconfigurational time dependent Hartree method, include coupling between the two modes that are active in isomerization and the background molecular vibrational environment. Noting previously unsuccessful computations highlights the significance of this result.

15.
J Chem Phys ; 133(15): 151101, 2010 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-20969359

RESUMO

Coherent control of observables using the phase properties of weak light that induces one-photon transitions is considered. Measurable properties are shown to be categorizable as either class A, where control is not possible, or class B, where control is possible. Using formal arguments, we show that phase control in open systems can be environmentally assisted.

16.
Phys Rev Lett ; 97(19): 193202, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17155624

RESUMO

Coherent control techniques are computationally applied to cold (1 mK

17.
J Chem Phys ; 125(9): 094315, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16965088

RESUMO

Coherent control theory is applied to the control of Ne*(3s,(3)P2)+Ar((1)S0) collisions and computations are shown that display extensive control over these processes. Indeed we demonstrate that it is possible to essentially turn on and off the cross sections for both the Penning and associative ionization processes. This facility arises from the interference between matter waves induced by creating a linear superposition of the degenerate M={-2,-1,0,1,2} Zeeman sublevels of the Ne*(3s,(3)P2) target atom. The computations, conducted at collision energies in the 1-8 kcal/mole range, are based on combining, within the "rotating atom approximation," empirically derived and ab initio ionization widths.

18.
J Chem Phys ; 122(18): 184303, 2005 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-15918700

RESUMO

We investigate the classical and quantum mechanics of diatomic molecules in noncollinear (tilted) static electric and nonresonant linearly polarized laser fields. The classical diatomic in tilted fields is a nonintegrable system, and we study the phase space structure for physically relevant parameter regimes for the molecule KCl. While exhibiting low-energy (pendular) and high-energy (free-rotor) integrable limits, the rotor in tilted fields shows chaotic dynamics at intermediate energies, and the degree of classical chaos can be tuned by changing the tilt angle. We examine the quantum mechanics of rotors in tilted fields. Energy-level correlation diagrams are computed, and the presence of avoided crossings quantified by the study of nearest-neighbor spacing distributions as a function of energy and tilting angle. Finally, we examine the influence of classical periodic orbits on rotor wave functions. Many wave functions in the tilted field case are found to be highly nonseparable in spherical polar coordinates. Localization of wave functions in the vicinity of classical periodic orbits, both stable and unstable, is observed for many states.


Assuntos
Físico-Química/métodos , Algoritmos , Química/métodos , Modelos Estatísticos , Modelos Teóricos , Oscilometria , Física/métodos , Cloreto de Potássio/química , Teoria Quântica
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