Caracterización del HLA en una familia colombiana endogámica con síndrome de Usher

Resumen El síndrome de Usher es una enfermedad autosómica recesiva que se caracteriza por presentar retinitis pigmentosa, hipoacusia neurosensorial congénita y disfunción vestibular. El propósito de este trabajo es realizar la caracterización de hla en una familia colombiana endogámica que presenta síndrome de Usher. La metodología consiste en que con un previo consentimiento informado se realizó una genealogía de la familia y a cuatro pacientes confirmados clínicamente con síndrome de Usher y a cuatro fenotípicamente sanos se les tomó 5 ml de sangre periférica en tubos de venopunción con edta para luego realizar el aislamiento del dna por la técnica de salting out, conservados en buffer te a -8 °C y ajustada la muestra a una concentración de 8 μg/ml. Posteriormente a través de la técnica de pcr-ssp de mediana resolución se caracterizaron los antígenos de hla *a, *b, *drb1 y *dqb1. Los resultados obtenidos indican que la familia oriunda del Departamento del Huila presenta una marcada endogamia detectándose que todos los hermanos afectados, sus padres son hermanos también y una de las parejas a su vez tuvo una niña afectada, por lo que sus abuelos y padres son hermanos. En lo referente al hla, los alelos más frecuentemente encontrados fueron a30 b42 dr1 dq5 y a3 b45 dr12 y dq7, que no están asociados a la enfermedad. Estos resultados sugieren que dada la endogamia que muestra esta familia se presenta una gran acumulación de polimorfismos y mutaciones, por lo que es necesario realizar un proceso de asesoría genética para disminuir el riesgo de recurrencia. Abstract Usher syndrome is an autosomal recessive disease characterized by retinitis pigmentosa, congenital sensorineural hearing loss and vestibular dysfunction. The purpose of this work was to characterize hla in an inbred Colombian family that presents Usher Syndrome. The Methodology consisted in that a genealogy of the family was made and previous informed consent, from four patients clinically confirmed with Usher Syndrome and four phenotypically healthy patients 5 ml of peripheral blood were taken in venipuncture tubes with edta and then the dna isolation was performed with the technique of salting out, preserved in te buffer at -8 °C and adjusted the sample to a concentration of 8 μg/ml. The hla *A, *B, *DRB1 and *DQB1 antigens were then characterized by the medium-resolution pcr-ssp techniqu

Caracterización del HLA en una familia colombiana endogámica con síndrome de Usher

El síndrome de Usher es una enfermedad autosómica recesiva que se caracteriza por presentar retinitis pigmentosa, hipoacusia neurosensorial congénita y disfunción vestibular. El propósito de este trabajo es realizar la caracterización de hla en una familia colombiana endogámica que presenta síndrome de Usher. La metodología consiste en que con un previo consentimiento informado se realizó una genealogía de la familia y a cuatro pacientes confirmados clínicamente con síndrome de Usher y a cuatro fenotípicamente sanos se les tomó 5 ml de sangre periférica en tubos de venopunción con edta para luego realizar el aislamiento del dna por la técnica de salting out, conservados en buffer te a -8 °C y ajustada la muestra a una concentración de 8 μg/ml. Posteriormente a través de la técnica de pcr-ssp de mediana resolución se caracterizaron los antígenos de hla *a, *b, *drb1 y *dqb1. Los resultados obtenidos indican que la familia oriunda del Departamento del Huila presenta una marcada endogamia detectándose que todos los hermanos afectados, sus padres son hermanos también y una de las parejas a su vez tuvo una niña afectada, por lo que sus abuelos y padres son hermanos. En lo referente al hla, los alelos más frecuentemente encontrados fueron a30 b42 dr1 dq5 y a3 b45 dr12 y dq7, que no están asociados a la enfermedad. Estos resultados sugieren que dada la endogamia que muestra esta familia se presenta una gran acumulación de polimorfismos y mutaciones, por lo que es necesario realizar un proceso de asesoría genética para disminuir el riesgo de recurrencia

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Precision measurement of CP\it{CP} violation in the penguin-mediated decay Bs0→ϕϕB_s^{0}\rightarrow\phi\phi

A flavor-tagged time-dependent angular analysis of the decay $B_s^{0}\rightarrow\phi\phi$ is performed using $pp$ collision data collected by the LHCb experiment at % at $\sqrt{s}=13$ TeV, the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb^{-1}. The $\it{CP}$-violating phase and direct $\it{CP}$-violation parameter are measured to be $\phi_{s\bar{s}s} = -0.042 \pm 0.075 \pm 0.009$ rad and $|\lambda|=1.004\pm 0.030 \pm 0.009$, respectively, assuming the same values for all polarization states of the $\phi\phi$ system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using $pp$ collisions at center-of-mass energies of 7 and 8 TeV, yielding $\phi_{s\bar{s}s} = -0.074 \pm 0.069$ rad and $|lambda|=1.009 \pm 0.030$. This is the most precise study of time-dependent $\it{CP}$ violation in a penguin-dominated $B$ meson decay. The results are consistent with $\it{CP}$ symmetry and with the Standard Model predictions.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-001.html (LHCb public pages

Measurement of the Λb0→Λ(1520)μ+μ−\Lambda_{b}^{0}\to \Lambda(1520) \mu^{+}\mu^{-} differential branching fraction

The branching fraction of the rare decay $\Lambda_{b}^{0}\to \Lambda(1520) \mu^{+}\mu^{-}$ is measured for the first time, in the squared dimuon mass intervals, $q^2$, excluding the $J/\psi$ and $\psi(2S)$ regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of $9\ \mathrm{fb}^{-1}$. The result in the highest$q^{2}$interval,$q^{2} >15.0\ \mathrm{GeV}^2/c^4$, where theoretical predictions have the smallest model dependence, agrees with the predictions.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-050.html (LHCb public pages

Search for rare decays of D0 mesons into two muons

A search for the very rare D 0 → μ + μ − decay is performed using data collected by the LHCb experiment in proton-proton collisions at √ s = 7 , 8, and 13 TeV, corresponding to an integrated luminosity of 9     fb − 1 . The search is optimized for D 0 mesons from D * + → D 0 π + decays but is also sensitive to D 0 mesons from other sources. No evidence for an excess of events over the expected background is observed. An upper limit on the branching fraction of this decay is set at B ( D 0 → μ + μ − ) < 3.1 × 10 − 9 at a 90% C.L. This represents the world’s most stringent limit, constraining models of physics beyond the standard model

Measurement of the ratios of branching fractions R(D*) and R(D0)

The ratios of branching fractions R ( D ∗ ) ≡ B ( ¯ B → D ∗ τ − ¯ ν τ ) / B ( ¯ B → D ∗ μ − ¯ ν μ ) and R ( D 0 ) ≡ B ( B − → D 0 τ − ¯ ν τ ) / B ( B − → D 0 μ − ¯ ν μ ) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0     fb − 1 of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ − → μ − ν τ ¯ ν μ . The measured values are R ( D ∗ ) = 0.281 ± 0.018 ± 0.024 and R ( D 0 ) = 0.441 ± 0.060 ± 0.066 , where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ = − 0.43 . The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model

Precision measurement of CP violation in the penguin-mediated decay Bs0→ϕϕ

A flavor-tagged time-dependent angular analysis of the decay B 0 s → ϕ ϕ is performed using p p collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6     fb − 1 . The C P -violating phase and direct C P -violation parameter are measured to be ϕ s ¯ s s s = − 0.042 ± 0.075 ± 0.009     rad and | λ | = 1.004 ± 0.030 ± 0.009 , respectively, assuming the same values for all polarization states of the ϕ ϕ system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using p p collisions at center-of-mass energies of 7 and 8 TeV, yielding ϕ s ¯ s s s = − 0.074 ± 0.069     rad and | λ | = 1.009 ± 0.030 . This is the most precise study of time-dependent C P violation in a penguin-dominated B meson decay. The results are consistent with C P symmetry and with the standard model predictions