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2.
Ann Hepatol ; 27(3): 100684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35167956

RESUMO

INTRODUCTION AND OBJECTIVES: The emergence of SARS-CoV-2, which causes the coronavirus disease (COVID-19) has caused a great impact on healthcare systems worldwide, including hepatitis B and C viruses screening and elimination programs. The high number of COVID-19 hospitalizations represent a great opportunity to screen patients for hepatitis B virus (HBV) and hepatitis C virus (HCV), which was the aim of this study. MATERIAL AND METHODS: Cross-sectional, retrospective study performed between April 2020 and 20201 at a referral center in Mexico dedicated to the care of adults with severe/critical COVID-19. We retrieved clinical, demographic, and laboratory results from each patient´s medical records, including antibodies against HCV (anti-HCV), HBV surface antigen (HBsAg), antibodies against the HBV core antigen (anti-HBcAg), and antibodies against HBsAg (anti-HBsAg). RESULTS: Out of 3620 patients that were admitted to the hospital, 24 (0.66%), 4 (0.11%), and 72 (1.99%) tested positive for anti-HCV, HBsAg, and anti-HBcAg, respectively. Of all seronegative patients, 954 (27%) had undetectable anti-HBsAg and 401 (12%) had anti-HBsAg at protective levels. Blood transfusion was the most relevant risk factor. Only 9.7% of the anti-HBc positive, 25% of the HBsAg positive, and 52% of the anti-HCV positive were aware of their serological status. CONCLUSIONS: In this study we found a prevalence of anti-HCV of 0.66%, HBsAg in 0.11%, and isolated anti-HBcAg in 1.99%. We also found that HBV vaccination coverage has been suboptimal and needs to be reinforced. This study gave us a trustworthy insight of the actual seroprevalence in Mexico, which can help provide feedback to the Hepatitis National Elimination Plan.


Assuntos
COVID-19 , Hepatite B , Hepatite C , Adulto , COVID-19/diagnóstico , COVID-19/epidemiologia , Estudos Transversais , Hepacivirus , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C , Humanos , Pacientes Internados , México/epidemiologia , Encaminhamento e Consulta , Estudos Retrospectivos , SARS-CoV-2 , Estudos Soroepidemiológicos
3.
Front Physiol ; 10: 717, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275156

RESUMO

Vaccination is a widely used therapeutical strategy in aquaculture, but whether vaccination elicits stress responses in the central neuroendocrine system and enhances the crosstalk between the immune and endocrine systems in the brain or pituitary after vaccination is unclear. To answer this question two experiments using two different vaccine exposure routes, i.e., bath or intraperitoneal (i.p.) injection, were carried out on gilthead seabream (Sparus aurata L.). In the first one, the stress responses of fish subjected to waterborne Vibrio anguillarum bacterin were compared with responses after air exposure or their combination. In the second experiment, fish were subjected to an intraperitoneal injection of Lactococcus garvieae bacterin and we assessed the central stress response and also whether or not a significant immune response was induced in brain and pituitary. In both experiments, blood, brain and pituitary tissues were collected at 1, 6, and 24 h post stress for plasma hormone determination and gene expression analysis, respectively. Results indicated that bath vaccination induced a decreased central stress response compared to air exposure which stimulated both brain and pituitary stress genes. In the second experiment, injection vaccination kept unchanged plasma stress hormones except cortisol that raised at 6 and 24 h. In agreement, non-significant or slight changes on the transcription of stress-related genes were recorded, including the hormone genes of the hypothalamic pituitary interrenal (HPI) axis and other stress markers such as hsp70, hsp90, and mt genes in either brain or pituitary. Significant changes were observed, however, in crhbp and gr. In this second experiment the immune genes il1ß, cox2, and lys, showed a strong expression in both brain and pituitary after vaccination, notably il1ß which showed more than 10 fold raise. Overall, vaccination procedures, although showing a cortisol response, did not induce other major stress response in brain or pituitary, regardless the administration route. Other than main changes, the alteration of crhbp and gr suggests that these genes could play a relevant role in the feedback regulation of HPI axis after vaccination. In addition, from the results obtained in this work, it is also demonstrated that the immune system maintains a high activity in both brain and pituitary after vaccine injection.

4.
Rev Sci Instrum ; 89(10): 10I146, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399731

RESUMO

The Cherenkov mechanism used in Gas Cherenkov Detectors (GCDs) is exceptionally fast. However, the temporal resolution of GCDs, such as the Gamma Reaction History diagnostic at the National Ignition Facility (NIF), has been limited by the current state-of-the-art photomultiplier tube technology to ∼100 ps. The soon-to-be deployed Pulse Dilation Photomultiplier Tube (PD-PMT) at NIF will allow for temporal resolution comparable to that of the gas cell or ∼10 ps. Enhanced resolution will contribute to the quest for ignition in a crucial way through precision measurements of reaction history and ablator areal density (ρR) history, leading to better constrained models. Features such as onset of alpha heating, shock reverberations, and burn truncation due to dynamically evolving failure modes may become visible for the first time. Test measurements of the PD-PMT at Atomic Weapons Establishment confirmed that design goals have been met. The PD-PMT provides dilation factors of 2 to 40× in 6 increments. The GCD-3 recently deployed at the NIF has been modified for coupling to a PD-PMT and will soon be making ultrafast measurements.

5.
Rev Sci Instrum ; 89(10): 10F101, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399753

RESUMO

A point-projection soft X-ray Opacity Spectrometer (OpSpec) has been implemented to measure X-ray spectra from ∼1 to 2 keV on the National Ignition Facility (NIF). Measurement of such soft X-rays with open-aperture point-projection detectors is challenging because only very thin filters may be used to shield the detector from the hostile environment. OpSpec diffracts X-rays from 540 to 2100 eV off a potassium (or rubidium) acid phthalate (KAP or RbAP) crystal onto either image plates or, most recently, X-ray films. A "sacrificial front filter" strategy is used to prevent crystal damage, while 2 or 3 rear filters protect the data. Since May 2017, OpSpec has been recording X-ray transmission data for iron-magnesium plasmas on the NIF, at "Anchor 1" plasma conditions (temperature ∼150 eV, density ∼7 × 1021 e -/cm3). Upgrades improved OpSpec's performance on 6 NIF shots in August and December 2017, with reduced backgrounds and 100% data return using filter stacks as thin as 2.9 µm (total). Photometric noise is beginning to meet requirements, and further work will reduce systematic errors.

6.
Rev Sci Instrum ; 89(10): 10I148, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399772

RESUMO

Fusion reaction history and ablator areal density measurements for Inertial Confinement Fusion experiments at the National Ignition Facility are currently conducted using the Gamma Reaction History diagnostic (GRH_6m). Future Gas Cherenkov Detectors (GCDs) will ultimately provide ∼100x more sensitivity, reduce the effective temporal response from ∼100 to ∼10 ps, and lower the energy threshold from 2.9 to 1.8 MeV, relative to GRH_6m. The first phase toward next generation GCDs consisted of inserting the existing coaxial GCD-3 detector into a reentrant well which puts it within 4 m of the implosion. Reaction history and ablator gamma measurement results from this Phase I are discussed here. These results demonstrate viability for the follow-on Phases of (II) the use of a revolutionary new pulse-dilation photomultiplier tube to improve the effective measurement bandwidth by >10x relative to current PMT technology; and (III) the design of a NIF-specific "Super" GCD which will be informed by the assessment of the radiation background environment within the well described here.

7.
Mar Pollut Bull ; 133: 428-435, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30041332

RESUMO

Gold nanoparticles (AuNP) effects on Sparus aurata were evaluated on skin, gills and intestine by assessing the expression of immune genes and in peripheral blood evaluating genetic damage. Fish were exposed to 0.5 and 50 µg/L AuNP for 96 h. Results showed that exposure to 50 µg/L AuNP induced an upregulation in the expression of innate immune genes in gills (c3, lys, il1ß, tnfα, il6, il10 and tgfß) and intestine (il1ß, tnfα and il6). Furthermore, mRNA levels of hsp70 and hsp90 were increased in gills after exposure to 0.5 µg/L AuNP, when compared to 50 µg/L. Present data demonstrated the sensitivity of gills and intestines to AuNP exposure supporting their use in the study of fish responses to other nanoparticles. Genotoxic potential of AuNP was demonstrated by increased DNA strand breaks in red blood cells of fish exposed to AuNP, suggesting that AuNP represent a potential hazard to fish.


Assuntos
Proteínas de Peixes/genética , Nanopartículas Metálicas/toxicidade , Mucosa/efeitos dos fármacos , Dourada/imunologia , Animais , Dano ao DNA , Eritrócitos/efeitos dos fármacos , Proteínas de Peixes/imunologia , Brânquias/efeitos dos fármacos , Brânquias/imunologia , Ouro/química , Ouro/toxicidade , Interleucina-6/genética , Intestinos/efeitos dos fármacos , Intestinos/imunologia , RNA Mensageiro/metabolismo , Dourada/genética , Pele/efeitos dos fármacos , Pele/imunologia , Fator de Necrose Tumoral alfa/genética , Poluentes Químicos da Água/toxicidade
8.
Rev Neurol ; 64(6): 264-266, 2017 Mar 16.
Artigo em Espanhol | MEDLINE | ID: mdl-28272727

RESUMO

INTRODUCTION: The term 'painful tic convulsive' is used to describe the syndrome involving concomitant hemifacial spasm and ipsilateral trigeminal neuralgia. Vascular compression of the fifth and seventh cranial nerves is the most common cause, involving the entry and exit zone of rootlets coming from the brainstem; nevertheless, different etiologies of this syndrome has been previously reported. Treatment for this disease is based on surgical microvascular decompression of the nerve rootlets, but still a topic of debate. CASE REPORT: A 63-year-old woman with history of 14 years presenting left trigeminal neuralgia, associated with ipsilateral hemifacial spasm for more than ten years. Medical treatment was installed without adequate symptom control. Patient was subjected to surgical treatment via a microasterional approach, with dissection of arachnoid fibrous tissue surrounding fifth and seventh nerves during the first surgery. A second surgery was performed with insertion of a teflon fragment aside of each exit nerve root (V and VII-VIII complex). Symptoms resolved immediately after the surgery and has persisted during the 1-year follow-up. Painful tic convulsive etiology could be multifactorial. CONCLUSION: This report is the first clinical case describing basal arachnoiditis as a primary cause of painful tic convulsive.


TITLE: Presentacion inusual de un tic convulsivo doloroso.Introduccion. La presentacion clinica de un espasmo hemifacial asociado a neuralgia trigeminal ipsilateral se conoce como tic convulsivo doloroso. La causa mas comun de esta patologia es la compresion vascular de los nervios craneales V y complejo VII-VIII en la zona de entrada y salida de las raices en el tronco del encefalo, pero existen informes de diversas etiologias. Su tratamiento, aunque aun esta en discusion, se basa en la descompresion microvascular quirurgica. Caso clinico. Mujer de 63 años, con un cuadro de evolucion de 14 años de neuralgia trigeminal, con predominio en distribucion de la rama maxilar (V2) izquierda, asociado durante mas de 10 años a espasmo hemifacial ipsilateral. Tras fallar el tratamiento medico, se sometio a cirugia por abordaje microasterional, y en un primer momento se realizo una diseccion de adherencias aracnoideas firmes rodeando complejos nerviosos. En un segundo tiempo quirurgico se insertaron fragmentos de teflon en los sitios de entrada de los nervios V y complejo VII-VIII, y se logro una resolucion completa de la sintomatologia durante mas de un año. Conclusion. La etiologia del tic convulsivo doloroso en esta paciente fue aracnoiditis basal, lo cual la convierte en el unico caso comunicado hasta el momento con dicha etiologia.


Assuntos
Aracnoidite/complicações , Espasmo Hemifacial/etiologia , Neuralgia do Trigêmeo/etiologia , Feminino , Humanos , Pessoa de Meia-Idade
9.
Rev Sci Instrum ; 87(11): 11E732, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910331

RESUMO

The newest generation of Gas Cherenkov Detector (GCD-3) employed in Inertial Confinement Fusion experiments at the Omega Laser Facility has provided improved performance over previous generations. Comparison of reaction histories measured using two different deuterium-tritium fusion products, namely gamma rays using GCD and neutrons using Neutron Temporal Diagnostic (NTD), have provided added credibility to both techniques. GCD-3 is now being brought to the National Ignition Facility (NIF) to supplement the existing Gamma Reaction History (GRH-6m) located 6 m from target chamber center (TCC). Initially it will be located in a reentrant well located 3.9 m from TCC. Data from GCD-3 will inform the design of a heavily-shielded "Super" GCD to be located as close as 20 cm from TCC. It will also provide a test-bed for faster optical detectors, potentially lowering the temporal resolution from the current ∼100 ps state-of-the-art photomultiplier tubes (PMT) to ∼10 ps Pulse Dilation PMT technology currently under development.

10.
Rev Sci Instrum ; 87(11): 11E718, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910419

RESUMO

The gas Cherenkov detector 3 was designed at Los Alamos National Laboratory for use in inertial confinement fusion experiments at both the Omega Laser Facility and the National Ignition Facility. This instrument uses a low-Z gamma-to-electron convertor plate and high pressure gas to convert MeV gammas into UV/visible Cherenkov photons for fast optical detection. This is a follow-on diagnostic from previous versions, with two notable differences: the pressure of the gas is four times higher, and it allows the use of fluorinated gas, requiring metal seals. These changes force significant changes in the window component, having a unique set of requirements and footprint limitations. The selected solution for this component, a sapphire window brazed into a stainless steel flange housing, is described.

11.
Rev Sci Instrum ; 85(11): 11E122, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430301

RESUMO

The Gamma-to-Electron Magnetic Spectrometer (GEMS) diagnostic is designed to measure the prompt γ-ray energy spectrum during high yield deuterium-tritium (DT) implosions at the National Ignition Facility (NIF). The prompt γ-ray spectrum will provide "burn-averaged" observables, including total DT fusion yield, total areal density (ρR), ablator ρR, and fuel ρR. These burn-averaged observables are unique because they are essentially averaged over 4π, providing a global reference for the line-of-sight-specific measurements typical of x-ray and neutron diagnostics. The GEMS conceptual design meets the physics-based requirements: ΔE/E = 3%-5% can be achieved in the range of 2-25 MeV γ-ray energy. Minimum DT neutron yields required for 15% measurement uncertainty at low-resolution mode are: 5 × 10(14) DT-n for ablator ρR (at 0.2 g/cm(2)); 2 × 10(15) DT-n for total DT yield (at 4.2 × 10(-5) γ/n); and 1 × 10(16) DT-n for fuel ρR (at 1 g/cm(2)).

12.
Rev Sci Instrum ; 85(11): 11E124, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430303

RESUMO

A new Gas Cherenkov Detector (GCD) with low-energy threshold and high sensitivity, currently known as Super GCD (or GCD-3 at OMEGA), is being developed for use at the OMEGA Laser Facility and the National Ignition Facility (NIF). Super GCD is designed to be pressurized to ≤400 psi (absolute) and uses all metal seals to allow the use of fluorinated gases inside the target chamber. This will allow the gamma energy threshold to be run as low at 1.8 MeV with 400 psi (absolute) of C2F6, opening up a new portion of the gamma ray spectrum. Super GCD operating at 20 cm from TCC will be ∼400 × more efficient at detecting DT fusion gammas at 16.7 MeV than the Gamma Reaction History diagnostic at NIF (GRH-6m) when operated at their minimum thresholds.

13.
Rev Sci Instrum ; 83(10): 10D311, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126838

RESUMO

The gamma-to-electron magnetic spectrometer, having better than 5% energy resolution, is proposed to resolve γ-rays in the range of E(o) ± 20% in single shot, where E(o) is the central energy and is tunable from 2 to 25 MeV. Gamma-rays from inertial confinement fusion implosions interact with a thin Compton converter (e.g., beryllium) located at approximately 300 cm from the target chamber center (TCC). Scattered electrons out of the Compton converter enter an electromagnet placed outside the NIF chamber (approximately 600 cm from TCC) where energy selection takes place. The electromagnet provides tunable E(o) over a broad range in a compact manner. Energy resolved electrons are measured by an array of quartz Cherenkov converters coupled to photomultipliers. Given 100 detectable electrons in the energy bins of interest, 3 × 10(14) minimum deuterium/tritium (DT) neutrons will be required to measure the 4.44 MeV (12)C γ-rays assuming 200 mg/cm(2) plastic ablator areal density and 3 × 10(15) minimum DT neutrons to measure the 16.75 MeV DT γ-ray line.

14.
Rev Sci Instrum ; 82(11): 113504, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22128973

RESUMO

A new, versatile Thomson parabola ion energy (TPIE) analyzer has been designed, constructed, and used at the OMEGA-EP facility. Laser-accelerated multi-MeV ions from hemispherical C targets are transmitted through a W pinhole into a multi-kG magnetic field and subsequently through a parallel electric field of up to 25 kV/cm. The ion drift region has a user-selected length of 10, 50, or 80 cm. With the highest fields, 400-MeV C(6+) and C(5+) may be resolved. TPIE is ten-inch manipulator (TIM)-mounted at OMEGA-EP and can be used opposite either of the EP ps beams. The instrument runs on pressure-interlocked 15-Vdc power available in EP TIM carts. Flux control derives from the insertion depth into the target chamber and the user-selected pinhole dimensions. The detector consists of CR39 backed by an image plate. A fully relativistic simulation code for calculating ion trajectories was employed for design optimization. Excellent agreement of code predictions with the actual ion positions on the detectors is observed. Through pit counting of carbon-ion tracks in CR39, it is shown that conversion efficiency of laser light to energetic carbon ions exceeds ~5% for these targets.

15.
J Phys Condens Matter ; 22(4): 045303, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-21386311

RESUMO

The influence of an intense laser field on shallow-donor states in cylindrical GaAs-Ga(1-x)Al(x)As quantum-well wires under an external magnetic field applied along the wire axis is theoretically studied. Numerical calculations are performed in the framework of the effective-mass approximation, and the impurity energies corresponding to the ground state and 2p(±) excited states are obtained via a variational procedure. The laser-field effects on the shallow-donor states are considered within the extended dressed-atom approach, which allows one to treat the problem 'impurity + heterostructure + laser field + magnetic field' as a renormalized 'impurity + heterostructure + magnetic field' problem, in which the laser effects are taken into account through a renormalization of both the conduction-band effective mass and fundamental semiconductor gap.

16.
Rev Sci Instrum ; 79(10): 10F305, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044618

RESUMO

The newly upgraded TRIDENT high-energy-density (HED) facility provides high-energy short-pulse laser-matter interactions with powers in excess of 200 TW and energies greater than 120 J. In addition, TRIDENT retains two long-pulse (nanoseconds to microseconds) beams that are available for simultaneous use in either the same experiment or a separate one. The facility's flexibility is enhanced by the presence of two separate target chambers with a third undergoing commissioning. This capability allows the experimental configuration to be optimized by choosing the chamber with the most advantageous geometry and features. The TRIDENT facility also provides a wide range of standard instruments including optical, x-ray, and particle diagnostics. In addition, one chamber has a 10 in. manipulator allowing OMEGA and National Ignition Facility (NIF) diagnostics to be prototyped and calibrated.

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