HIV‐1 infection triggers lateral membrane diffusion following interaction of the viral envelope with cell surface receptors. We show that these membrane changes are necessary for infection, as ...initial gp120–CD4 engagement leads to redistribution and clustering of membrane microdomains, enabling subsequent interaction of this complex with HIV‐1 co‐receptors. Disruption of cell membrane rafts by cholesterol depletion before viral exposure inhibits entry by both X4 and R5 strains of HIV‐1, although viral replication in infected cells is unaffected by this treatment. This inhibitory effect is fully reversed by cholesterol replenishment of the cell membrane. These results indicate a general mechanism for HIV‐1 envelope glycoprotein‐mediated fusion by reorganization of membrane microdomains in the target cell, and offer new strategies for preventing HIV‐1 infection.
New variants of SARS-CoV-2 Cantón, Rafael; De Lucas Ramos, Pilar; García-Botella, Alejandra ...
Revista española de quimioterapia,
10/2021, Letnik:
34, Številka:
5
Journal Article
Odprti dostop
The emergence and spread of new variants of SARS-CoV-2 has produced enormous interest due to their possible implication in the improved transmissibility of the virus, their consequences in the ...individual evolution of the infection, as well as in the possible escape from the immunity generated by the current vaccines. The variants that attract most attention are those of public health concern, including B.1.1.7 (UK), P.1 (Brazilian) and B.1.351 (South African). This list is extended by the variants of interest that emerge and are expanding in certain countries but are found sporadically in others, such as B.1.427 and B.1.429 (Californians) or B.1.617 (Indian). Whole genome sequencing or strategies specifically targeting the spicule gene are used in the microbiology laboratories for characterization and detection. The number of infected individuals, the sanitary situation of each country, epidemiological measures and vaccination strategies influence its dispersion and new variants are expected to emerge. This emergence can only be avoided today by increasing the vaccinated population in all countries and by not relaxing epidemiological containment measures. It is not excluded that in the future it will be necessary to revaccinate against new variants.
Abstract The DARWIN observatory is a proposed next-generation experiment to search for particle dark matter and for the neutrinoless double beta decay of $$^{136}$$ 136 Xe. Out of its 50 t total ...natural xenon inventory, 40 t will be the active target of a time projection chamber which thus contains about 3.6 t of $$^{136}$$ 136 Xe. Here, we show that its projected half-life sensitivity is $$2.4\times {10}^{27}\,{\hbox {year}}$$ 2.4 × 10 27 year , using a fiducial volume of 5 t of natural xenon and 10 year of operation with a background rate of less than 0.2 events/(t $$\cdot $$ · year) in the energy region of interest. This sensitivity is based on a detailed Monte Carlo simulation study of the background and event topologies in the large, homogeneous target. DARWIN will be comparable in its science reach to dedicated double beta decay experiments using xenon enriched in $$^{136}$$ 136 Xe.
Abstract For the first time, a small dual-phase (liquid/gas) xenon time projection chamber was equipped with a top array of silicon photomultipliers for light and charge readout. Here we describe the ...instrument in detail, as well as the data processing and the event position reconstruction algorithms. We obtain a spatial resolution of $$\sim 1.5\,\text {mm}$$ ∼1.5mm in the horizontal plane. To characterise the detector performance, we show calibration data with internal $$^{83\text {m}}\hbox {Kr}$$ 83mKr and $$^{37}\hbox {Ar}$$ 37Ar sources, and we detail the production of the latter as well as its introduction into the system. We finally compare the observed light and charge yields down to electronic recoil energies of $$2.82\,\text {keV}$$ 2.82keV to predictions based on NEST v2.0.
A low-energy electronic recoil calibration of XENON1T, a dual-phase xenon time projection chamber, with an internal 37Ar source was performed. This calibration source features a 35-day half-life and ...provides two mono-energetic lines at 2.82 keV and 0.27 keV. The photon yield and electron yield at 2.82 keV are measured to be (32.3±0.3) photons/keV and (40.6±0.5) electrons/keV, respectively, in agreement with other measurements and with NEST predictions. The electron yield at 0.27 keV is also measured and it is (68.0+6.3−3.7) electrons/keV. The 37Ar calibration confirms that the detector is well-understood in the energy region close to the detection threshold, with the 2.82 keV line reconstructed at (2.83±0.02) keV, which further validates the model used to interpret the low-energy electronic recoil excess previously reported by XENON1T. The ability to efficiently remove argon with cryogenic distillation after the calibration proves that 37Ar can be considered as a regular calibration source for multi-tonne xenon detectors.
Monkeypox in humans: a new outbreak Martín-Delgado, M C; Martín Sánchez, F J; Martínez-Sellés, M ...
Revista española de quimioterapia,
12/2022, Letnik:
35, Številka:
6
Journal Article
Odprti dostop
Infection caused by Monkeypox Virus (MPVX) has small rodents as its natural reservoir and both monkeys and humans are occasional hosts. The causative agent is an Orthopoxvirus (MPVX) that was ...isolated in monkeys in 1958 and proved capable of passing to humans in 1970. It remained contained in Africa, causing isolated episodes of infection, until 2003 when an outbreak occurred in the United States following importation of animals from that continent. Since then, anecdotal cases have continued to be reported outside Africa, usually very clearly linked to travelers to those countries, but in May 2022, a broad outbreak of this disease has begun, now affecting several continents, with the emergence of human cases of MPVX (H-MPVX) infection mainly among Men that have Sex with Men (MSM). The disease has an incubation time ranging from 5 to 15 days and is characterized by the presence of pustules, fever, malaise and headache. The presence of significant regional lymphadenopathy is a differential feature with episodes of classical smallpox. Proctitis and pharyngitis, with minimal skin lesions, may be another form of presentation. Diagnosis can be confirmed by PCR testing of lesions or by demonstration of MPVX in other body fluids or tissues, although in the appropriate epidemiologic setting the clinical picture is highly suggestive of the disease. Effective drug treatment has been developed as part of programs to protect against potential bioterrorist agents and smallpox vaccinees are known to have high protection against monkeypox. New vaccines are available, but neither the drugs nor the vaccines are yet freely available on the market. The prognosis of the disease appears, at least in adults in developed countries, to be good, with very low mortality figures and much less aggressive behavior than that described in classical smallpox. Isolation measures, essential for the control of the outbreak, have been published by the health authorities.
A frequently observed fact in clinical practice is the relationship between Substance Abuse Disorders and Personality Disorders (PD). Epidemiological investigations have found that diagnoses of PD ...seem to increase vulnerability to other pathologies, including substance abuse and addiction, and it is possible to speak of comorbidity or dual pathology.
To describe the comorbidity between PD and substance abuse disorders.
Systematic review of the literature on the subject. The databases consulted were Dialnet, Pubmed and Cochrane.
The various studies allow estimating that between 65% and 90% of subjects treated for substance abuse or dependence have at least one concomitant PT. Studies show a higher prevalence of Cluster C for alcohol consumption and Histrionic, Narcissistic, Boundary and Antisocial Disorders (Cluster B) for illegal drugs, mainly cocaine. Cluster B is the one that the literature has most related to substance use. It is also the group in which there is a greater predominance of impulsivity, which would be worth remembering its role as a vulnerability factor for addictions.
What the research has shown is that a good deal of the problems that accompany substance use come from dysfunctional patterns of behavior that are maintained over time with high stability and can justify, in part, both the persistence of The addictive behavior as the difficulty of handling the patients who present them. At present, although the high comorbidity between TP and substance use is sufficiently documented, many questions still remain to be solved.
Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. ...Using 3 × 10
cosmic rays with energies above 8 × 10
electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km
sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of Formula: see text percent toward right ascension α
= 100 ± 10 degrees and declination δ
= Formula: see text degrees
That direction indicates an extragalactic origin for these ultrahigh-energy particles.
Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with
...E
≥
6
×
10
19
eV by analyzing cosmic rays with energies above
E
≥
5
×
10
18
eV arriving within an angular separation of approximately 15
∘
. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.
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