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1.
Am J Transplant ; 24(2S1): S534-S556, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38431366

RESUMEN

This year's chapter on vascularized composite allograft (VCA) encompasses reviews of data collected from 2014 (when VCA was included in the Final Rule) through 2022. The present Annual Data Report shows that the number of VCA recipients in the United States continues to be small and has remained consistent from the prior report. The data continue to be limited by sample size, with trends persistently demonstrating a predominance of White males in the young/middle-aged population as both donors and recipients for nonuterus VCA transplants, and White women younger than 35 years as the predominant recipients of uterus transplant. Similar to the 2021 report, there were only eight failed uterus grafts and one failed nonuterus VCA graft reported from 2014 through 2022. Standardization of definitions of success and failure as well as outcome measures for the different VCA types remain unmet needs in VCA transplantation.


Asunto(s)
Aloinjertos Compuestos , Alotrasplante Compuesto Vascularizado , Masculino , Persona de Mediana Edad , Humanos , Femenino , Estados Unidos , Aloinjertos Compuestos/trasplante , Donantes de Tejidos
2.
New Phytol ; 244(3): 1086-1100, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39187985

RESUMEN

Population genetics theory predicts a relationship between fitness, genetic diversity (H0) and effective population size (Ne), which is often tested through heterozygosity-fitness correlations (HFCs). We tested whether population and individual fertility and heterozygosity are correlated in two endangered Mexican spruces (Picea martinezii and Picea mexicana) by combining genomic, demographic and reproductive data (seed development and germination traits). For both species, there was a positive correlation between population size and seed development traits, but not germination rate. Individual genome-wide heterozygosity and seed traits were only correlated in P. martinezii (general-effects HFC), and none of the candidate single nucleotide polymorphisms (SNPs) associated with individual fertility showed heterozygote advantage in any species (no local-effects HFC). We observed a single and recent (c. 30 thousand years ago (ka)) population decline for P. martinezii; the collapse of P. mexicana occurred in two phases separated by a long period of stability (c. 800 ka). Recruitment always contributed more to total population census than adult trees in P. mexicana, while this was only the case in the largest populations of P. martinezii. Equating fitness to either H0 or Ne, as traditionally proposed in conservation biology, might not always be adequate, as species-specific evolutionary factors can decouple the expected correlation between these parameters.


Asunto(s)
Evolución Biológica , Especies en Peligro de Extinción , Bosques , Aptitud Genética , Reproducción , Semillas , Árboles , Árboles/genética , Árboles/fisiología , Semillas/genética , Semillas/fisiología , Semillas/crecimiento & desarrollo , Reproducción/genética , Picea/genética , Picea/fisiología , Picea/crecimiento & desarrollo , Heterocigoto , Germinación/genética , Polimorfismo de Nucleótido Simple/genética , Densidad de Población , Variación Genética
3.
Artículo en Inglés | MEDLINE | ID: mdl-38741198

RESUMEN

OBJECTIVES: The aims of this study were to investigate the prevalence of dose reduction in patients with SLE treated with belimumab (BEL) in Spain, analyze treatment modalities, and determine impact on control of disease activity. METHODS: Retrospective longitudinal and multicentre study of SLE patients treated with BEL. Data on disease activity, treatments and outcomes were recorded before and after reduction (6-12 months), and they were compared. RESULTS: A total of 324 patients were included. The dose was reduced in 29 patients (8.9%). The dosing interval was increased in 9 patients receiving subcutaneous BEL and in 6 patients receiving intravenous BEL. The dose per administration was reduced in 16 patients.Pre-reduction status was remission (2021 DORIS) in 15/26 patients (57.7%) and LLDAS in 23/26 patients (88.5%). After reduction, 2/24 patients (8.3%) and 3/22 patients (13.6%) lost remission at 6 months and 12 months, respectively (not statistically significant [NS]). As for LLDAS, 2/23 patients (8.7%) and 2/21 patients (9.5%) lost their status at 6 and 12 months, respectively (NS). Significantly fewer patients were taking glucocorticoids (GCs) at their 12-month visit, although the median dose of GCs was higher at the 12-month visit (5 [0.62-8.75] vs 2.5 [0-5] at baseline). CONCLUSION: Doses of BEL can be reduced with no relevant changes in disease activity-at least in the short term-in a significant percentage of patients, and most maintain the reduced dose. However, increased clinical or serologic activity may be observed in some patients. Consequently, tighter post-reduction follow-up is advisable.

4.
Purinergic Signal ; 20(2): 115-125, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37246192

RESUMEN

During the establishment of neuronal circuits, axons and dendrites grow and branch to establish specific synaptic connections. This complex process is highly regulated by positive and negative extracellular cues guiding the axons and dendrites. Our group was pioneer in describing that one of these signals are the extracellular purines. We found that extracellular ATP, through its selective ionotropic P2X7 receptor (P2X7R), negatively regulates axonal growth and branching. Here, we evaluate if other purinergic compounds, such as the diadenosine pentaphosphate (Ap5A), may module the dynamics of dendritic or axonal growth and branching in cultured hippocampal neurons. Our results show that Ap5A negatively modulates the dendrite's growth and number by inducing transient intracellular calcium increases in the dendrites' growth cone. Interestingly, phenol red, commonly used as a pH indicator in culture media, also blocks the P2X1 receptors, avoided the negative modulation of Ap5A on dendrites. Subsequent pharmacological studies using a battery of selective P2X1R antagonists confirmed the involvement of this subunit. In agreement with pharmacological studies, P2X1R overexpression caused a similar reduction in dendritic length and number as that induced by Ap5A. This effect was reverted when neurons were co-transfected with the vector expressing the interference RNA for P2X1R. Despite small hairpin RNAs reverting the reduction in the number of dendrites caused by Ap5A, it did not avoid the dendritic length decrease induced by the polyphosphate, suggesting, therefore, the involvement of a heteromeric P2X receptor. Our results are indicating that Ap5A exerts a negative influence on dendritic growth.


Asunto(s)
Adenosina Trifosfato , Fosfatos de Dinucleósidos , Receptores Purinérgicos P2 , Adenosina Trifosfato/farmacología , Receptores Purinérgicos P2/metabolismo , Neuronas/metabolismo , Dendritas/metabolismo , Hipocampo/metabolismo
5.
Photochem Photobiol Sci ; 23(5): 901-918, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38584224

RESUMEN

Pd/ZnO nanocomposites were successfully synthesized by means of one and two pot synthesis and applied in the photodegradation of Rh6G. The nanocomposites were characterized by XRD, SEM, TEM, FTIR and micro-Raman spectroscopies. It was found the presence of PdZn2, PdO and agglomerated particles in the support surface for the Palladium-based nanocomposites fabricated by one-pot route; the two-step method allowed the formation of spherical Pd nanoparticles, with homogeneous distribution in the nanocomposite matrix, with an average size of 2.16 nm. The results show higher photocatalytic efficiency for the samples fabricated under the two-step approach compared to the one-pot synthesis. Based on experimental results, density functional theory (DFT) calculations were carried out to understand the enhancement photocatalytic of Pd/ZnO nanocomposites. To achieve it, the ZnO (001) and (101) surfaces were built and decorated by different Pd coverages. The theoretical results indicated two different photocatalytic mechanisms. In ZnO (001) case, the electrons flowed from surface to Pd, generating the superoxide radical anion (⋅O2-). Furthermore, the density of states of the ZnO (001) surface was modified by impurity Pd-d states at proximity to the conduction states, which may work as electron acceptors states. On the other hand, we found that the electrons flow from Pd to ZnO (101) surface, inducing the formation of ⋅OH and ⋅O2- for the degradation of Rh6G. The density of states of the ZnO (101) revealed a reduction in its bandgap, due to Pd-d states localized above valence states. Hence, our theoretical results suggest that the Pd-d states may facilitate the mobility of electrons and holes in (001) and (101) surfaces, respectively, reducing the rate of charge recombination.

6.
Phys Chem Chem Phys ; 26(30): 20576-20584, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39037201

RESUMEN

The electronic structure and derived optical properties of five synthesized metal-dicyanoaurate(I), (K)M[Au(CN)2], (M = Mn, Co, Ni, Zn and Cd), coordination polymers are described from a combined experimental analysis and theoretical study based on density functional theory. In this sense, the topological features that influence the electronic structure, which in turn give rise to electronic transitions associated with the band gap energy, are studied from first principles calculations (with hybrid HSE06 and GGA-PBE density functionals) and electronic spectroscopy. The impact of gold (through spin-orbit coupling) and aurophilic interactions on the electronic transitions that gives rise to optical properties is described. The calculated projected density of states and band dispersion diagrams shed light on the molecular orbital distribution and the role of a dicyanoaurate(I) molecular block as the origin of the optical properties. Infrared, Raman and ultraviolet-visible spectroscopic analyses reveal the effect that charge transfer interactions, of a metal → ligand and metal → metal nature, have on the electronic behavior within the solids through association with the polarizing power of transition metals and gold atoms.

7.
Nature ; 563(7731): 365-368, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429552

RESUMEN

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

8.
Mol Divers ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153018

RESUMEN

Diet habits and nutrition quality significantly impact health and disease. Here is delve into the intricate relationship between diet habits, nutrition quality, and their direct impact on health and homeostasis. Focusing on (-)-Epicatechin, a natural flavanol found in various foods like green tea and cocoa, known for its positive effects on cardiovascular health and diabetes prevention. The investigation encompasses the absorption, metabolism, and distribution of (-)-Epicatechin in the human body, revealing a diverse array of metabolites in the circulatory system. Notably, (-)-Epicatechin demonstrates an ability to activate nitric oxide synthase (eNOS) through the G protein-coupled estrogen receptor (GPER). While the precise role of GPER and its interaction with classical estrogen receptors (ERs) remains under scrutiny, the study employs computational methods, including density functional theory, molecular docking, and molecular dynamics simulations, to assess the physicochemical properties and binding affinities of key (-)-Epicatechin metabolites with GPER. DFT analysis revealed distinct physicochemical properties among metabolites, influencing their reactivity and stability. Rigid and flexible molecular docking demonstrated varying binding affinities, with some metabolites surpassing (-)-Epicatechin. Molecular dynamics simulations highlighted potential binding pose variations, while MMGBSA analysis provided insights into the energetics of GPER-metabolite interactions. The outcomes elucidate distinct interactions, providing insights into potential molecular mechanisms underlying the effects of (-)-Epicatechin across varied biological contexts.

9.
Appl Opt ; 63(13): 3600-3608, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856545

RESUMEN

The generation of self-focusing beams of extreme ultraviolet (XUV) radiation using the focal cone high harmonic generation (FCHHG) technique is examined for high energy lasers. The FCHHG geometry is created by passing a focusing laser beam through a gas sheet prior to reaching focus and thus creating a converging beam of high harmonic radiation. This leads to a larger interaction area that increases the total area of XUV emission while not exceeding the saturation intensity of the target atoms or increasing the density of the atoms. Such a method allows for scaling of HHG to any incident laser power. An experiment was conducted demonstrating such scaling to incident 400 TW pulses, showing both the expected spectral signature of HHG and the converging cone of XUV radiation. It was found that this technique is very sensitive to spatial non-uniformity in the driving laser, which has become more prevalent in high energy laser systems.

10.
Pediatr Radiol ; 54(9): 1540-1548, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38987429

RESUMEN

BACKGROUND: Pediatric iliofemoral venous thromboembolism that is resistant to conventional treatments poses significant management challenges. Stent placement represents a potentially underutilized strategy in children when stenosis or thrombosis persists intraprocedurally or recurs postoperatively, despite treatments such as venoplasty, lysis, and thrombectomy. OBJECTIVE: This study aims to report our institutional experience with iliofemoral stenting in 17 pediatric patients with recurrent iliofemoral venous thromboembolism or stenosis. MATERIALS AND METHODS: We performed an IRB-approved retrospective review of pediatric patients (<18 years of age) who underwent iliofemoral venous stenting for recurrent stenosis or thrombosis between January 2012 and December 2022 at a single tertiary care institution. Patient demographics, risk factors for venous thromboembolism, presenting symptoms, and procedural characteristics were recorded. The primary outcome was stent patency rates at interval imaging follow-up. RESULTS: Seventeen patients with mean age of 14.6 years (range 7-17) and mean BMI of 27.7 were stented during the study period. Sixteen of 17 patients presented with evidence of May-Thurner anatomy. 14/17 patients presented with acute iliofemoral venous thromboembolism, 2/17 with chronic venous thromboembolism, and 1/17 with left lower extremity swelling without thrombosis. Seventy-three total angiographic procedures were performed, which included angioplasty, lysis, and thrombectomy, and 23 stent placements. Patients underwent an average of 3 procedures (range 1-9) over a mean of 2.8 months (range 0-17 months) prior to undergoing stent placement. Stents were deployed successfully in all patients. The median follow-up was 18 months (range, 1-77 months). Primary and secondary patency rates were 13/17 (76%) and 14/14 (100%) at 12 months and 12/17 (71%) and 14/14 (100%) at 24 months, respectively. CONCLUSION: In our experience of 17 patients, stent placement appears to be a durable option for children with iliofemoral venous thromboembolism following failure to establish vessel patency or development of recurrent thrombosis/stenosis postoperatively.


Asunto(s)
Vena Femoral , Vena Ilíaca , Stents , Humanos , Niño , Femenino , Masculino , Adolescente , Estudios Retrospectivos , Vena Femoral/cirugía , Vena Femoral/diagnóstico por imagen , Vena Ilíaca/diagnóstico por imagen , Vena Ilíaca/cirugía , Tromboembolia Venosa/diagnóstico por imagen , Resultado del Tratamiento , Recurrencia
11.
Occup Med (Lond) ; 74(3): 218-224, 2024 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-38527057

RESUMEN

BACKGROUND: Occupational footwear is intended to provide protection against the risks associated with work activities. The choice of footwear is complex due to the welfare, health and safety conditions of workers. AIMS: To identify the injuries and problems caused by occupational footwear through a systematic review of the existing literature. METHODS: A literature search was carried out in the Cumulative Index to Nursing and Allied Health Literature, Dialnet Plus, Pubmed, Scientific Electronic Library Online, Medline, Scopus and Web of Science databases over the period 2000-23, following the PRISMA Declaration guidelines. RESULTS: A total of 27 studies were included in the review. The results indicated that there is a wide variety of injuries caused by occupational footwear: from dermal injuries (e.g. calluses) and injuries to the nail apparatus to inflammatory pathologies such as plantar fasciitis or bursitis. In addition, inappropriate footwear can cause pain in the ankle and foot, knees, hips and lower back. Other results include the discomfort derived from the footwear itself. CONCLUSIONS: Inappropriate footwear can cause injuries to the foot and other related bone structures. Further studies are needed on the detection of foot injuries caused by occupational footwear and the levels of action at this level to improve the worker's health, the adaptability of the footwear to the wearer, and the worker's comfort and adherence to the footwear.


Asunto(s)
Traumatismos Ocupacionales , Zapatos , Humanos , Bursitis/etiología , Fascitis Plantar/etiología , Traumatismos de los Pies/etiología , Enfermedades Profesionales/etiología , Traumatismos Ocupacionales/etiología , Zapatos/efectos adversos
12.
Rhinology ; 62(1): 2-12, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37814591

RESUMEN

BACKGROUND: Dexmedetomidine has been shown to effectively control intraoperative bleeding and improve surgical field visualization. However, its value in endonasal surgeries remains a matter of debate. METHODOLOGY: We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials for studies comparing dexmedetomidine with placebo in endonasal surgeries. Outcomes included bleeding, operative time (OT), surgeon’s satisfaction, postoperative pain (POP), and nausea/vomiting (PONV). For statistical analysis, we used RevMan 5.4.1, and assessed heterogeneity with I2 statistics. RESULTS: We included a total of 1386 patients from 22 studies. In the placebo group, there was higher bleeding volume, whereas the dexmedetomidine group showed lower scores on the Fromme-Boezaart scale. Additionally, the surgeon satisfaction risk ratio (RR) increased, and OT was reduced in the dexmedetomidine group. The dexmedetomidine group had lower incidences of POP and PONV. CONCLUSIONS: In endonasal surgeries, dexmedetomidine was associated with improvements in surgical field visualization as evidenced by reduced intraoperative bleeding and postoperative morbidities.


Asunto(s)
Dexmedetomidina , Humanos , Dexmedetomidina/uso terapéutico , Náusea y Vómito Posoperatorios/prevención & control , Dolor Postoperatorio/tratamiento farmacológico , Suplementos Dietéticos
13.
J Nematol ; 56(1): 20240031, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39114457

RESUMEN

Metaparasitylenchus hypothenemi is an endoparasitic nematode of the coffee berry borer Hypothenemus hampei. The nematode has only been recorded across a limited geographical range in coffee-growing areas of southeastern Mexico. Because of its confined geographical distribution, the effect of altitude, temperature, and mean annual precipitation on M. hypothenemi's presence/absence in the Soconusco region of Mexico was investigated. The geographical distribution of this parasite was predicted based on current data, using geographical information systems (GIS), the MaxEnt algorithm, and historical data to improve the prediction accuracy for other Neotropical regions. In Soconusco, the presence of this parasite is directly related to annual precipitation, especially in the areas with the highest annual rainfall (4000 - 4700 mm/year). Four species distribution models were generated for the Neotropical region with environmental variables for sites with parasite presence data, predicting a range of possible distribution with a high probability of occurrence in southeastern Mexico and southwestern Guatemala and a low probability in areas of Central and South America. Characterization of the abiotic habitat conditions suitable for M. hypothenemi development allows us to predict its distribution in the Neotropics and contributes to our understanding of its ecological relationship with environmental variables.

14.
Exp Astron (Dordr) ; 57(1): 5, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39308933

RESUMEN

State-of-the-art 19th century spectroscopy led to the discovery of quantum mechanics, and 20th century spectroscopy led to the confirmation of quantum electrodynamics. State-of-the-art 21st century astrophysical spectrographs, especially ANDES at ESO's ELT, have another opportunity to play a key role in the search for, and characterization of, the new physics which is known to be out there, waiting to be discovered. We rely on detailed simulations and forecast techniques to discuss four important examples of this point: big bang nucleosynthesis, the evolution of the cosmic microwave background temperature, tests of the universality of physical laws, and a real-time model-independent mapping of the expansion history of the universe (also known as the redshift drift). The last two are among the flagship science drivers for the ELT. We also highlight what is required for the ESO community to be able to play a meaningful role in 2030s fundamental cosmology and show that, even if ANDES only provides null results, such 'minimum guaranteed science' will be in the form of constraints on key cosmological paradigms: these are independent from, and can be competitive with, those obtained from traditional cosmological probes.

15.
Am J Transplant ; 23(2 Suppl 1): S523-S545, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37132342

RESUMEN

Year 2020 marked the first OPTN/SRTR Annual Data Report that included a chapter on vascularized composite allograft (VCA), which encompassed reviews of data collected between 2014 (when VCA was included in the Final Rule) and 2020. The present Annual Data Report shows that the number of VCA recipients in the United States continues to be small and trended downward in 2021. While data continue to be limited by sample size, trends continue to show a predominance in White, young/middle-aged, male recipients. Similar to the 2020 report, eight uterus and one non-uterus VCA graft failures were reported from 2014 through 2021. Critical to advancement of VCA transplantation will be the standardization of definitions, protocols, and outcome measures for the different VCA types. Like intestinal transplants, it is likely that VCA transplants will be concentrated and performed at referral transplant centers.


Asunto(s)
Aloinjertos Compuestos , Trasplantes , Alotrasplante Compuesto Vascularizado , Persona de Mediana Edad , Masculino , Humanos , Estados Unidos , Aloinjertos Compuestos/trasplante
16.
J Neuroinflammation ; 20(1): 135, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37264394

RESUMEN

INTRODUCTION: Gut microbiota plays a critical role in the regulation of immune homeostasis. Accordingly, several autoimmune disorders have been associated with dysbiosis in the gut microbiota. Notably, the dysbiosis associated with central nervous system (CNS) autoimmunity involves a substantial reduction of bacteria belonging to Clostridia clusters IV and XIVa, which constitute major producers of short-chain fatty acids (SCFAs). Here we addressed the role of the surface receptor-mediated effects of SCFAs on mucosal T-cells in the development of CNS autoimmunity. METHODS: To induce CNS autoimmunity, we used the mouse model of experimental autoimmune encephalomyelitis (EAE) induced by immunization with the myelin oligodendrocyte glycoprotein (MOG)-derived peptide (MOG35-55 peptide). To address the effects of GPR43 stimulation on colonic TCRαß+ T-cells upon CNS autoimmunity, mucosal lymphocytes were isolated and stimulated with a selective GPR43 agonist ex vivo and then transferred into congenic mice undergoing EAE. Several subsets of lymphocytes infiltrating the CNS or those present in the gut epithelium and gut lamina propria were analysed by flow cytometry. In vitro migration assays were conducted with mucosal T-cells using transwells. RESULTS: Our results show a sharp and selective reduction of intestinal propionate at the peak of EAE development, accompanied by increased IFN-γ and decreased IL-22 in the colonic mucosa. Further analyses indicated that GPR43 was the primary SCFAs receptor expressed on T-cells, which was downregulated on colonic TCRαß+ T-cells upon CNS autoimmunity. The pharmacologic stimulation of GPR43 increased the anti-inflammatory function and reduced the pro-inflammatory features in several TCRαß+ T-cell subsets in the colonic mucosa upon EAE development. Furthermore, GPR43 stimulation induced the arrest of CNS-autoreactive T-cells in the colonic lamina propria, thus avoiding their infiltration into the CNS and dampening the disease development. Mechanistic analyses revealed that GPR43-stimulation on mucosal TCRαß+ T-cells inhibits their CXCR3-mediated migration towards CXCL11, which is released from the CNS upon neuroinflammation. CONCLUSIONS: These findings provide a novel mechanism involved in the gut-brain axis by which bacterial-derived products secreted in the gut mucosa might control the CNS tropism of autoreactive T-cells. Moreover, this study shows GPR43 expressed on T-cells as a promising therapeutic target for CNS autoimmunity.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Receptores de Antígenos de Linfocitos T alfa-beta , Ratones , Animales , Autoinmunidad , Disbiosis , Sistema Nervioso Central , Glicoproteína Mielina-Oligodendrócito/toxicidad , Péptidos , Ratones Endogámicos C57BL
17.
Opt Express ; 31(18): 29452-29464, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37710745

RESUMEN

In this work, we develop experimentally a Fabry-Perot fiber optic interferometer applied to the measurement of autocorrelation of complex dynamic pulses generated by a figure-eight fiber laser. The principle is based in the superposition of multiple pulses, which requires two partially reflecting flat surfaces in parallel, resulting in a simple and compact autocorrelator design. The autocorrelation trace obtained exhibits a typical double-scaled structure for noise-like pulses (NLPs), with an ultrashort coherence spur on the order of 100 fs riding upon a broad pedestal of 120 ps. Finally, we show experimentally that the developed Fabry-Perot device is able to measure accurately the autocorrelation of NLPs, as confirmed by comparing the measurement with that of a conventional autocorrelator scheme based on a Michelson interferometer, with the additional advantages of a more compact setup and a much easier alignment procedure compared to the latter.

18.
Phys Rev Lett ; 130(12): 120601, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027873

RESUMEN

Significant progress has been made with multipartite entanglement of discrete qubits, but continuous variable systems may provide a more scalable path toward entanglement of large ensembles. We demonstrate multipartite entanglement in a microwave frequency comb generated by a Josephson parametric amplifier subject to a bichromatic pump. We find 64 correlated modes in the transmission line using a multifrequency digital signal processing platform. Full inseparability is verified in a subset of seven modes. Our method can be expanded to generate even more entangled modes in the near future.

19.
BMC Cardiovasc Disord ; 23(1): 13, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635626

RESUMEN

BACKGROUND: Right ventricular (RV) dysfunction in patients with non-ischemic dilated cardiomyopathy (NICM) is associated with cardiovascular events. To analyze the feasibility of assessing RV myocardial deformation by feature tracking (FT)-cardiac magnetic resonance (CMR), and its usefulness as a prognostic marker. METHODS: Retrospective study of NICM patients undergoing CMR. Longitudinal FT-RV free wall (LFT-RVFW) and fractional area change (FAC) were obtained. Correlation with standard RV parameters was studied. An association with combined event (heart failure (HF), ICD implantation or cardiovascular death) was assessed using a logistic regression model. RESULTS: 98 patients (64 ± 13 years) were included. Left ventricular (LV) systolic function (LVEF 29.5 ± 9.6%, 47% with LVEF ≥ 30%) and RV (RVEF 52.2 ± 14.6%, 72% with RVEF ≥ 45%). Follow-up of 38 ± 17 months, 26.5% presented at least one admission for HF. An excellent correlation of LFT-RVFW (r = 0.82) and FAC (r = 0.83) with RVEF was evident. No association of RV-FT parameters with prognosis entire study population was found. However, in patients with LVEF ≥ 30%, admissions for HF were associated with lower LFT-RVFW (-21.6 ± 6.6% vs -31.3 ± 10%; p = 0.006) and FAC (36.6 ± 9.6% vs 50.5 ± 13.4%; p < 0.001) values. Similar differences were observed when only patients with RVEF ≥ 45% were considered. An LFT-RVFW cut-off point of -19.5% and FAC of 36.5% showed good prognostic performance. Decreased LFT-RVFW or FAC represented an independent predictor of combined event in patients with LVEF ≥ 30%. CONCLUSIONS: In NICM patients without severe LV dysfunction, decreased values of LFT-RVFW and/or FAC were associated with HF admissions, independently of RVEF.


Asunto(s)
Cardiomiopatía Dilatada , Insuficiencia Cardíaca , Disfunción Ventricular Derecha , Humanos , Estudios Retrospectivos , Imagen por Resonancia Cinemagnética , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Cardiomiopatía Dilatada/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Función Ventricular Derecha , Volumen Sistólico
20.
J Opt Soc Am A Opt Image Sci Vis ; 40(11): 1994-2001, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38038064

RESUMEN

We show the construction of 3D solids (volumetric 3D models) of SARS-CoV-2 viral particles from the tomographic studies (videos) of SARS-CoV-2-infected tissues. To this aim, we propose a video analysis (tomographic images) by frames (medical images of the virus), which we set as our metadata. We optimize the frames by means of Fourier analysis, which induces a periodicity with simple structure patterns to minimize noise filtering and to obtain an optimal phase of the objects in the image, focusing on the SARS-CoV-2 cells to obtain a medical image under study phase (MIS) (process repeated over all frames). We build a Python algorithm based on Legendre polynomials called "2DLegendre_Fit," which generates (using multilinear interpolation) intermediate images between neighboring MIS phases. We used this code to generate m images of size M×M, resulting in a matrix with size M×M×M (3D solid). Finally, we show the 3D solid of the SARS-CoV-2 viral particle as part of our results in several videos, subsequently rotated and filtered to identify the glicoprotein spike protein, membrane protein, envelope, and the hemagglutinin esterase. We show the algorithms in our proposal along with the main MATLAB functions such as FourierM and Results as well as the data required for the program execution in order to reproduce our results.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Análisis de Fourier , Tomografía , Virión , Algoritmos
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