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1.
Hum Immunol ; 84(11): 571-577, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37777360

ABSTRACT

BACKGROUND: Immigrants represented 21.8% of cases in a Spanish cohort of hospitalised patients with COVID-19, a proportion exceeding the percentage of immigrants in that area's total population. Among the ethnic-related genetic risk factors for COVID-19, human leukocyte antigen (HLA) genotypes in diverse populations might bias the response to SARS-CoV-2 infection and/or progression. Similarly, genetic differences in natural killer-activating and inhibitory receptors could play a role in the immune system's response to the viral infection. METHODS: We characterised HLA alleles and KIR genes in 52 Ecuadorian patients hospitalised for moderate and severe COVID-19 and 87 Ecuadorian controls from the general population living in the same area. RESULTS: There was a significantly increased frequency of the HLA-B*39 antigen and the activating KIR2DS4 receptor in the presence of its HLA-C*04 ligand in the COVID-19 group when compared with the control group. In contrast, there was a significant reduction in the frequency of carriers of KIR2DL1 and of the KIR3DL1/Bw4 receptor/ligand combination among COVID-19 group. On the other hand, HLA-A*24:02 and HLA-DRB1*09:01 alleles showed significantly lower frequencies specifically in the severe COVID-19 group. CONCLUSION: HLA-B*39 alleles might be genetic risk factors for developing COVID-19 in Ecuadorian individuals. In the presence of its ligand C*04, the natural killer-activating receptor KIR2DS4 might also increase the risk of developing COVID-19, while, in the presence of HLA-Bw4 alleles, the inhibitory receptor KIR3DL1 might play a protective role. Patients with COVID-19 who carry HLA-A*24:02 and HLA-DRB1*09:01 alleles might be protected against more severe forms of COVID-19.


Subject(s)
COVID-19 , Receptors, KIR , Humans , HLA-DRB1 Chains/genetics , Ligands , Protective Factors , Ecuador/epidemiology , Receptors, KIR/genetics , COVID-19/genetics , SARS-CoV-2 , HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , HLA-B Antigens/genetics , Genotype , HLA-A Antigens/genetics
2.
HLA ; 101(2): 195-196, 2023 02.
Article in English | MEDLINE | ID: mdl-36196570

ABSTRACT

The extended genomic sequence of HLA-DQB1*04:59N allele.


Subject(s)
Genomics , Humans , Alleles , Colombia , HLA-DQ beta-Chains/genetics
3.
Phys Chem Chem Phys ; 24(22): 14072-14084, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35640548

ABSTRACT

We present a detailed theoretical survey of the electronic structure of excited states of the CO2 molecule, with the aim of providing a well-defined theoretical framework for the quantum dynamical studies at energies beyond 12 eV from the ground state. One of the major goals of our work is to emphasize the need for dealing with the presence of both molecular valence and Rydberg states. Although a CASSCF/MRCI approach can be used to appropriately describe the lowest-lying valence states, it becomes incapable of describing the upper electronic states due to the exceedingly large number of electronic excitations required. To circumvent this we employ instead the EOM-CCSD monoconfigurational method to describe the manifold of both valence and Rydberg states in the Franck-Condon region and then a matching procedure to connect these EOM-CCSD eigensolutions with those obtained from CASSCF/MRCI in the outer region, thus ensuring the correct asymptotic behavior. Within this hybrid level of theory, we then analyze the role of valence and Rydberg states in the dynamical mechanism of the photodissociation of quasi-linear CO2 into CO + O fragments, by considering a simple but effective 1D multistate non-adiabatic model for the ultrafast C-O bond break up. We show evidence that the metastability of the Rydberg states must be accounted for in the ultrafast dynamics since they produce changes in the photodissociation yields within the first tens of fs.

4.
J Chem Phys ; 154(9): 094120, 2021 Mar 07.
Article in English | MEDLINE | ID: mdl-33685158

ABSTRACT

We address topics related to molecules coupled to quantum radiation. The formalism of light-matter interaction is different for classical and quantum fields, but some analogies remain, such as the formation of light induced crossings. We show that under particular circumstances, the molecular dynamics under quantum or classical fields produce similar results, as long as the radiation is prepared as a Fock state and far from ultra-strong coupling regimes. At this point, the choice of specific initial Fock states is irrelevant since the dynamics scales. However, in realistic multistate molecular systems, radiative scaling may fail due to the presence of simultaneous efficient non-radiative couplings in the dynamics. Polar molecules have permanent dipoles, and within the context of the full quantum Rabi model with a Pauli-Fierz Hamiltonian, they play a crucial role in the polaritonic dynamics since both permanent dipole moments and self-energy terms produce drastic changes on the undressed potential energy surfaces at high coupling strengths. We also gauge the effect of including rotational degrees of freedom in cavity molecular photodynamics. For diatomic molecules, the addition of rotation amounts to transform (both with classical or quantum fields) a light induced crossing into a light induced conical intersection. However, we show that conical intersections due to molecular rotation do not represent the standard properties of well-known efficient intrinsic conical intersections inasmuch they do not enhance the quantum transition rates.

5.
Phys Rev Lett ; 122(6): 063603, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30822050

ABSTRACT

We propose an experiment to find evidence of the formation of light-induced crossings provoked by cavity quantum radiation on simple molecules by using state-of-the-art optical cavities, molecular beams, pump-probe laser schemes, and velocity mapping detectors for fragmentation. The procedure is based on prompt excitation and subsequent dissociation in a three-state scheme of a polar diatomic molecule, with two ^{1}Σ states (ground and first excited) coupled first by the UV pump laser and then by the cavity radiation, and a third fully dissociative state ^{1}Π coupled through the delayed UV/V probe laser. The observed enhancement of photodissociation yields in the ^{1}Π channel at given time delays between the pump and probe lasers unambiguously indicates the formation of a light-induced crossing between the two ^{1}Σ field-dressed potential energy curves of the molecule. Also, the production of cavity photons out of the vacuum field state via nonadiabatic effects represents a showcase of a molecular dynamical Casimir effect. To simulate the experiment outcome, we perform ab initio coherent quantum dynamics of the molecule LiF subject to external lasers and quantum cavity interactions in the strong coupling regime, using a product grid representation of the total polaritonic wave function for both vibrational and photon degrees of freedom.

6.
J Phys Chem A ; 122(8): 2266-2278, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29338227

ABSTRACT

The quantum photodynamics of a simple diatomic molecule with a permanent dipole immersed within an optical cavity containing a quantized radiation field is studied in detail. The chosen molecule under study, lithium fluoride (LiF), is characterized by the presence of an avoided crossing between the two lowest 1Σ potential energy curves (covalent-ionic diabatic crossing). Without field, after prompt excitation from the ground state 1 1Σ, the excited nuclear wave packet moves back and forth in the upper 2 1Σ state, but in the proximity of the avoided crossing, the nonadiabatic coupling transfers part of the nuclear wave packet to the lower 1 1Σ state, which eventually leads to dissociation. The quantized field of a cavity also induces an additional light crossing in the modified dressed potential energy curves with similar transfer properties. To understand the entangled photonic-nuclear dynamics, we solve the time-dependent Schrödinger equation by using the multiconfigurational time-dependent Hartree method (MCTDH). The single mode quantized field of the cavity is represented in the coordinate space instead of in the Fock space, which allows us to deal with the field as an additional vibrational mode within the MCTDH procedure on equal footing. We prepare the cavity with different quantum states of light, namely, Fock states, coherent states, and squeezed coherent states. Our results reveal pure quantum light effects on the molecular photodynamics and the dissociation yields of LiF, which are quite different from the light-undressed case and which cannot be described in general by a semiclassical approach using classical electromagnetic fields.

7.
Joint Bone Spine ; 78(3): 309-11, 2011 May.
Article in English | MEDLINE | ID: mdl-21195005

ABSTRACT

Atherosclerosis is the main cause of coronary artery aneurysm, however they can be observed in connective tissue diseases such as systemic lupus erythematosus and vasculitis. Kawasaki's disease and polyarteritis nodosa (PAN) are the systemic vasculitis that more often present coronary artery aneurysms. There are descriptions in the literature that small vessel vasculitis such as microscopic polyangiitis and PAN could develop coronary artery aneurysm, which are infrequent in other ANCA-associated vasculitis. Here, we report the case of a 25-year-old man who developed an extensive anterior myocardial infarct. The coronary angiogram showed coronary artery aneurysms, on laboratory ANCA C positivity with elevated levels of anti-proteinase 3 antibodies were present. He was treated with high doses of corticosteroids and cyclophosphamide with resolution of the aneurysms.


Subject(s)
Coronary Aneurysm/diagnosis , Granulomatosis with Polyangiitis/pathology , Myocardial Infarction/diagnosis , Adult , Antibodies, Antineutrophil Cytoplasmic/analysis , Antibodies, Antineutrophil Cytoplasmic/immunology , Coronary Aneurysm/etiology , Coronary Angiography/methods , Cyclophosphamide/therapeutic use , Glucocorticoids/therapeutic use , Granulomatosis with Polyangiitis/complications , Granulomatosis with Polyangiitis/drug therapy , Humans , Male , Methylprednisolone/therapeutic use , Myeloblastin/analysis , Myeloblastin/immunology , Myocardial Infarction/etiology , Treatment Outcome
8.
Rev. colomb. quím. (Bogotá) ; 38(1): 109-116, abr. 2009. ilus
Article in English | LILACS | ID: lil-636648

ABSTRACT

A method to calculate angular distributions for electrons ejected from fixed-in-space molecular hydrogen molecules subject to ultrashort intense laser pulses is proposed, based on the ab initio solution of the time-dependent Schrodinger equation. This method of solution allows for a temporal picture of interferences arising in the dissociative ionization channel (in the proton kinetic energy spectrum) due to the presence of the autoionizing double excited states in the Hydrogen molecule. In particular, we show how this autoionization during the dissociative photoionization process may also induce a counterintuitive asymmetry in the angular distribution of the ionized electron with respect to nuclei inversion, in spite of dealing with an homonuclear system.


Se propone un método para calcular distribuciones angulares de electrones ionizados en la molécula de hidrógeno fija en el espacio sometida a pulsos láser intensos y ultracortos, basado en la solución desde primeros principios de la ecuación de Schrodinger dependiente del tiempo. Esta solución nos permite tener una visión temporal de la interferencias generadas en el canal de ionización disociativa (en el espectro de energía cinética de los protones) debido a la presencia de la autoionización de estados doblemente excitados de la molécula de hidrógeno. Se muestra específicamente cómo la autoionización durante el proceso de fotoionización disociativa también puede inducir una asimetría en la distribución angular del electrón ionizado con respecto a la inversión nuclear, un efecto no intuitivo a pesar de estar tratando con un sistema homonuclear.


Propõe-se um método para calcular as distribuições angulares de elétrons ionizados de uma molécula de hidrogênio fixa no espaço, sujeita a pulsos de laser intensos e ultra-curtos, baseado na soluçao desde primeiros princípios da equaçao de Schrõdinger dependente do tempo. Esta soluçao nos permite ter uma visão temporal das interferências geradas no canal de ionizaçao dissociativa (no espectro de energia cinética dos prótons) devido á presença da auto-ionização de estados duplamente excitados da molécula de hidrogênio. Mostra-se especificamente como a auto-ionização durante o processo de foto-ionização dissociativa pode também induzir uma assimetria na distribuição angular do elétron ionizado com respeito á inversão nuclear, um efeito não intuitivo apesar de estar se tratando de um sistema homonuclear.

9.
Cardiovasc Revasc Med ; 6(3): 99-107, 2005.
Article in English | MEDLINE | ID: mdl-16275605

ABSTRACT

PURPOSE: Based on our preclinic studies with autologous unfractionated bone marrow (AUBM) via coronary sinus with transitory occlusion, a clinic study in patients with chronic refractory angina was designed. The objectives were to evaluate tolerance of the procedure, safety, and feasibility with 1 year follow-up. METHODS AND MATERIALS: Clinical study with inclusion and exclusion criteria defined by an Independent Clinical Committee was carried out. Fifteen patients underwent transcoronary sinus administration with a 15-min occlusion of freshly aspirated and filtered AUBM (60-120 ml). Feasibility was evaluated with Seattle Angina Questionnaire (SAQ), Canadian Cardiovascular Society (CCS) angina classification, perfusion dipyridamole, and coronary angiography. RESULTS: There were no changes in the tolerance parameters. There were no deaths or myocardial infarction during the follow-up. Three patients were readmitted into the hospital. During the follow-up, one patient was diagnosed with cancer of the lung. Improvement of 30% in the quality of life was evaluated by SAQ. The CCS angina classification showed that the mean angina class was 3.0+/-0.53 at baseline, which improved to 1.6+/-0.63 at 1 year (P<.001). Perfusion imaging (core lab) showed improvement in 12 of 15 patients, with a mean improvement of 40.9% at rest (22 vs. 13) (P<.01) and 45.3% at stress (26.5 vs. 14.5) (P<.05). Coronary angiography showed more collateral vessels in 10 of 15 patients. CONCLUSIONS: We can conclude that AUBM via coronary sinus is feasible in patients with chronic refractory angina after 1 year follow-up, and it appears to be safe.


Subject(s)
Angina Pectoris/surgery , Bone Marrow Transplantation , Coronary Stenosis/surgery , Aged , Angina Pectoris/pathology , Angina Pectoris/physiopathology , Coronary Angiography , Coronary Circulation , Coronary Stenosis/pathology , Coronary Stenosis/physiopathology , Feasibility Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myocardial Reperfusion , Patient Readmission , Pilot Projects , Prospective Studies , Quality of Life , Sickness Impact Profile , Time Factors , Tomography, Emission-Computed, Single-Photon , Transplantation, Autologous , Treatment Outcome
10.
Acta méd. colomb ; 21(1): 10-6, ene.-feb. 1996. tab
Article in Spanish | LILACS | ID: lil-183352

ABSTRACT

Se estudiaron 26 pacientes diabéticos insulino-dependientes y 56 individuos sanos de la ciudad de Medellín. Se utilizaron 240 antisueros para las clases I y II del complejo mayor de histocompatibilidad, utilizando la técnica de microlinfocitotoxicidad de Terasaki. Los antígenos HLA de la clase II también se analizaron siguiendo los protocolos del XI Taller Internacional de Histocompatibilidad, amplificando el DNA por medio de la técnica de PCR y las hibridaciones se hicieron con sondas de oligonucleótidos seleccionados para HLA-DRB1, DQA1, DQB1. En los antígenos de la clase I, el HLA B18 se identificó en el 46 porciento de los pacientes comparado con 12.5 porciento de los controles; el riesgo relativo (RR) fue de 3.7. Lo contrario ocurrió con el B44, que se determinó en 7.6 porciento de los enfermos y en 25 porciento de los sanos. En cuanto a los antígenos de clase II, los alelos DRB1*0405 y *0301 se encontraron asociados a suceptibilidad, con un RR de 61.3 y 6.6, respectivamente.


Subject(s)
Humans , Diabetes Mellitus, Type 1/genetics , Genetic Markers , HLA Antigens
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