Coronavirus-19 disease risk and protective factors associated with HLA/KIR polymorphisms in Ecuadorian patients residing in Madrid.

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.

Polar diatomic molecules in optical cavities: Photon scaling, rotational effects, and comparison with classical fields.

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.

Revealing the Presence of Potential Crossings in Diatomics Induced by Quantum Cavity Radiation.

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.

Entangled Photonic-Nuclear Molecular Dynamics of LiF in Quantum Optical Cavities.

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.

Determinación de marcadores genéticos en pacientes con diabetes tipo I y población sana

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.