RESUMEN
OBJECTIVE: The interferon-gamma releasing assay (IGRA) has been widely used to diagnose latent tuberculosis infection (TBI). However, there are limited data on the association between performance in the IGRA and risk of tuberculosis disease (TBD), as well as on the appropriate IGRA threshold for initiating TBI treatment. METHODS: The analysis was performed using the IGRA results in the Korean Military Manpower Administration database (January 2017 to December 2021), and TBD cases reported to the Korean Military Medical Command (January 2017 to June 2023). All Korean candidates for 18-month military service underwent the IGRA in the pre-enlistment examination, and enlistees who tested positive (≥0.35 IU/mL) were advised to receive TBI treatment before enlistment. RESULTS: From 2017 to 2021, 1 647 941 individuals were screened, with 29 574 testing positive for IGRA. Excluding nonenlistees namely individuals with TBD before enlistment, 19 387 individuals were IGRA positive and 1 356 324 IGRA negative. Of the positives, 4351 were excluded due to discontinued or ongoing TBI treatment at or after enlistment. During follow-up of 9219 untreated and 5818 treated positive individuals and 1 356 324 negatives, TBD occurred in 22 of the IGRA-positive individuals (97.5/100 000 person-years [95% CI, 61.1-147.7]), predominantly in the untreated group (18 cases, 130.1/100 000 person-years [95% CI, 77.1-205.7]) compared to the treated group (4 cases, 45.9/100 000 person-years [95% CI 12.5 - 117.4]), whereas 57 cases occurred in the IGRA-negative group (2.8/100 000 person-years [95% CI, 2.2-3.6]). Elevating the cutoff of IGRA from 0.35 IU/mL to 1.33 IU/mL increased positive predictive value (0.2% vs. 0.4%, p 0.03), with insignificant loss of sensitivity (24% vs. 20%, p 0.69) and decreased numbers needing treatment from 790.5 to 415.3. DISCUSSION: Elevated IGRA levels before enlistment are associated with risk of TBD during military service. It is worth considering raising the IGRA threshold for treatment of TBI in cohorts of healthy, young military individuals.
RESUMEN
OBJECTIVE: Drug-induced parkinsonism (DIP) is a frequently encountered diagnostic possibility when considering Parkinson's disease (PD). While olfactory dysfunction is a common clinical feature in PD, the comparison of olfactory function between the two conditions remains insufficient. This study aimed to compare olfactory function, including threshold, discrimination, and identification (TDI) profiles, between PD and DIP. METHODS: Consecutive patients with drug-naïve PD (n = 78) or DIP (n = 31) confirmed through dopamine transporter imaging were enrolled in this study. The YSK olfactory function (YOF) test, composed of TDI domains culturally familiar odorants to Koreans, was administered to all patients. RESULTS: In the study population, patients with DIP were significantly older than patients with PD. Over 70% of patients in each group had hyposmia or anosmia, and there was no significant difference in the occurrence of olfactory dysfunction between the two groups. In addition, there were no differences in the total YOF score and threshold score between the two groups. Meanwhile, the PD group had a significantly lower discrimination and identification score than the DIP group after adjusting for age, sex, the existence of diabetes, disease duration, and cognitive function. CONCLUSION: This study demonstrated that detailed olfactory profiles are different in PD and DIP, even though olfactory dysfunction can be observed in both conditions.
RESUMEN
Surface defects of metal halide perovskite nanocrystals (PNCs) substantially compromise the optoelectronic performances of the materials and devices via undesired charge recombination. However, those defects, mainly the vacancies, are structurally entangled with each other in the PNC lattice, necessitating a delicately designed strategy for effective passivation. Here, a synergistic metal ion doping and surface ligand exchange strategy is proposed to passivate the surface defects of CsPbBr3 PNCs with various divalent metal (e.g., Cd2+ , Zn2+, and Hg2+ ) acetate salts and didodecyldimethylammonium (DDA+ ) via one-step post-treatment. The addition of metal acetate salts to PNCs is demonstrated to suppress the defect formation energy effectively via the ab initio calculations. The developed PNCs not only have near-unity photoluminescence quantum yield and excellent stability but also show luminance of 1175 cd m-2 , current efficiency of 65.48 cd A-1 , external quantum efficiency of 20.79%, wavelength of 514 nm in optimized PNC light-emitting diodes with Cd2+ passivator and DDA ligand. The "organic-inorganic" hybrid engineering approach is completely general and can be straightforwardly applied to any combination of quaternary ammonium ligands and source of metal, which will be useful in PNC-based optoelectronic devices such as solar cells, photodetectors, and transistors.
RESUMEN
As structure prediction methods are generating millions of publicly available protein structures, searching these databases is becoming a bottleneck. Foldseek aligns the structure of a query protein against a database by describing tertiary amino acid interactions within proteins as sequences over a structural alphabet. Foldseek decreases computation times by four to five orders of magnitude with 86%, 88% and 133% of the sensitivities of Dali, TM-align and CE, respectively.
Asunto(s)
Algoritmos , Proteínas , Bases de Datos de Proteínas , Proteínas/química , Aminoácidos , Programas InformáticosRESUMEN
Perovskite defects are a major hurdle in the efficiency and stability of perovskite solar cells (PSCs). While various defect passivation materials have been explored, most are insulators that hinder charge transport. This study investigates the potential of two different π-conjugated polyelectrolytes (CPEs), MPS2-TEA and PCPDTBT2-TMA, as semiconducting additives in PSCs. The CPEs differ in electrical conductivity, offering a unique approach to bridge defect mitigation and charge carrier transport. Unlike previous uses of CPEs mainly as interlayers or charge transport layers, we explore their direct effect on defect passivation within a perovskite layer. Secondary ion microscopy reveals the even distribution of CPEs within the perovskite layer and their efficient defect passivation potential is studied through various spectroscopic analyses. Comparing MPS2-TEA and PCPDTBT2-TMA, we find MPS2-TEA to be superior in defect passivation. The highly conductive nature of PCPDTBT2-TMA due to self-doping diminishes its defect passivation ability. The negative sulfonate groups in the side chains of PCPDTBT2-TMA stabilize polarons, reducing defect passivation capability. Finally, the PSCs with MPS2-TEA achieve remarkable power conversion efficiencies (PCEs) of 22.7% for 0.135 cm2 and 20.0% for large-area (1 cm2) cells. Furthermore, the device with MPS2-TEA maintained over 87.3% of initial PCE after 960 h at continuous 1-sun illumination and 89% of PCE after 850 h at 85 °C in a nitrogen glovebox without encapsulation. This highlights CPEs as promising defect passivation additives, unlocking potential for improved efficiency and stability not only in PSCs but also in wider applications.
RESUMEN
Objectives: More than half of patients with acute ischemic stroke develop post-stroke cognitive impairment (PSCI), a significant barrier to future neurological recovery. Thus, predicting cognitive trajectories post-AIS is crucial. Our primary objective is to determine whether brain network properties from electroencephalography (EEG) can predict post-stroke cognitive function using machine learning approach. Methods: We enrolled consecutive stroke patients who underwent both EEG during the acute stroke phase and cognitive assessments 3 months post-stroke. We preprocessed acute stroke EEG data to eliminate low-quality epochs, then performed independent component analysis and quantified network characteristics using iSyncBrain®. Cognitive function was evaluated using the Montreal cognitive assessment (MoCA). We initially categorized participants based on the lateralization of their lesions and then developed machine learning models to predict cognitive status in the left and right hemisphere lesion groups. Results: Eighty-seven patients were included, and the accuracy of lesion laterality prediction using EEG attributes was 97.0%. In the left hemispheric lesion group, the network attributes of the theta band were significantly correlated with MoCA scores, and higher global efficiency, clustering coefficient, and lower characteristic path length were associated with higher MoCA scores. Most features related to cognitive scores were selected from the frontal lobe. The predictive powers (R-squared) were 0.76 and 0.65 for the left and right stroke groups, respectively. Conclusion: Estimating EEG-based network properties in the acute phase of ischemic stroke through a machine learning model has a potential to predict cognitive outcomes after ischemic stroke.
RESUMEN
There have been few studies comparing the clinical characteristics and outcomes of SARS-CoV-2 pneumonia in individuals with and without moderately to severely immunocompromised conditions. We reviewed adult patients with SARS-CoV-2 infection who had radiologic evidence of pneumonia at a tertiary hospital in Seoul, South Korea, from February 2020 to April 2022. Moderately to severely immunocompromised status was defined as medical conditions or treatments that resulted in increased risk of severe COVID-19 and weakened immune response to COVID-19 vaccine as recommended by Centers for Disease Control and Prevention. The time to pneumonia development was defined as the time from symptom onset to the time when radiologic evidence of pneumonia was obtained. Viral clearance was defined as a Ct value > 30. COVID-19-related death was defined as 90-day death following imaging-confirmed pneumonia without any other plausible cause of death. A total of 467 patients with SARS-CoV-2 pneumonia were analyzed. Of these, 102 (22%) were moderately to severely immunocompromised. The median (IQR) time to pneumonia development was significantly longer in moderately to severely immunocompromised patients (9.5 [6-14] days) than the comparator (6 [3-8] days), p < 0.001), as was the median time to viral clearance (21 versus 12 days, p < 0.001). Moderately to severely immunocompromised status (aOR, 18.39; 95% CI, 5.80-58.30; p < 0.001) was independently associated with COVID-19-related death. Patients with moderately to severely immunocompromised conditions are likely to experience a more protracted course of SARS-CoV-2 pneumonia and a worse outcome than those without these conditions.
Asunto(s)
COVID-19 , SARS-CoV-2 , Estados Unidos , Adulto , Humanos , Vacunas contra la COVID-19 , Huésped Inmunocomprometido , Centros de Atención TerciariaRESUMEN
BACKGROUND: General control nonderepressible 2 (GCN2) senses amino acid deprivation and activates activating transcription factor 4 (ATF4), which regulates many adaptive genes. We evaluated the impact of AST-0513, a novel GCN2 inhibitor, on the GCN2-ATF4 pathway. Additionally, we evaluated the antitumor effects of AST-0513 in amino acid deprivation in head and neck squamous cell carcinoma (HNSCC) cell lines. METHODS: GCN2 expression in HNSCC patient tissues was measured by immunohistochemistry. Five HNSCC cell lines (SNU-1041, SNU-1066, SNU-1076, Detroit-562, FaDu) grown under amino acid deprivation conditions, were treated with AST-0513. After AST-0513 treatment, cell proliferation was measured by CCK-8 assay. Flow cytometry was used to evaluate apoptosis and cell cycle phase. In addition, immunoblotting was performed to evaluate the effect of AST-0513 on the GCN2-ATF4 pathway, cell cycle arrest, and apoptosis. RESULTS: We demonstrated that GCN2 was highly expressed in HNSCC patient tissues. AST-0513 inhibited the GCN2-ATF4 pathway in all five HNSCC cell lines. Inhibiting the GCN2-ATF4 pathway during amino acid deprivation reduced HNSCC cell proliferation and prevented adaptation to nutrient stress. Moreover, AST-0513 treatment led to p21 and Cyclin B1 accumulation and G2/M phase cycle arrest. Also, apoptosis was increased, consistent with increased bax expression, increased bcl-xL phosphorylation, and decreased bcl-2 expression. CONCLUSION: A novel GCN2 inhibitor, AST-0513, inhibited the GCN2-ATF4 pathway and has antitumor activity that inhibits proliferation and promotes cell cycle arrest and apoptosis. Considering the high expression of GCN2 in HNSCC patients, these results suggest the potential role of GCN2 inhibitor for the treatment of HNSCC.
RESUMEN
PURPOSE: NKG2A, an inhibitory receptor expressed on NK cells and T cells, leads to immune evasion by binding to HLA-E expressed on cancer cells. Here, we investigated the relationship between HLA-E surface expression on head and neck squamous cell carcinoma (HNSCC) cell lines and the efficacy of monalizumab, an NKG2A inhibitor, in promoting NK cell activity. METHODS: Six HNSCC cell lines were used as target cells. After exposure to IFN- γ, HLA-E surface expression on HNSCC cell lines was measured by flow cytometry. Peripheral blood mononuclear cells (PBMCs) from healthy donors and isolated NK cells were used as effector cells. NK cells were stimulated by treatment with IL-2 and IL-15 for 5 days, and NK cell-induced cytotoxicity was analyzed by CD107a degranulation and 51Cr release assays. RESULTS: We confirmed that HLA-E expression was increased by IFN-γ secreted by NK cells and that HLA-E expression was different for each cell line upon exposure to IFN-γ. Cell lines with high HLA-E expression showed stronger inhibition of NK cell cytotoxicity, and efficacy of monalizumab was high. Combination with cetuximab increased the efficacy of monalizumab. In addition, stimulation of isolated NK cells with IL-2 and IL-15 increased the efficacy of monalizumab, even in the HLA-E low groups. CONCLUSION: Monalizumab efficacy was correlated with HLA-E surface expression and was enhanced when NK cell activity was increased by cetuximab or cytokines. These results suggest that monalizumab may be potent against HLA-E-positive tumors and that monalizumab efficacy could be improved by promoting NK cell activity.
Asunto(s)
Neoplasias de Cabeza y Cuello , Interleucina-15 , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Cetuximab/farmacología , Interleucina-15/farmacología , Interleucina-2/farmacología , Leucocitos Mononucleares , Línea Celular Tumoral , Células Asesinas Naturales , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/metabolismo , Antígenos HLA-ERESUMEN
Semiconducting lead halide perovskite nanocrystals (PNCs) are regarded as promising candidates for next-generation optoelectronic devices due to their solution processability and outstanding optoelectronic properties. While the field of light-emitting diodes (LEDs) and photovoltaics (PVs), two prime examples of optoelectronic devices, has recently seen a multitude of efforts toward high-performance PNC-based devices, realizing both devices with high efficiencies and stabilities through a single PNC processing strategy has remained a challenge. In this work, diphenylpropylammonium (DPAI) surface ligands, found through a judicious ab-initio-based ligand search, are shown to provide a solution to this problem. The universal PNC ink with DPAI ligands presented here, prepared through a solution-phase ligand-exchange process, simultaneously allows single-step processed LED and PV devices with peak electroluminescence external quantum efficiency of 17.00% and power conversion efficiency of 14.92% (stabilized output 14.00%), respectively. It is revealed that a careful design of the aromatic rings such as in DPAI is the decisive factor in bestowing such high performances, ease of solution processing, and improved phase stability up to 120 days. This work illustrates the power of ligand design in producing PNC ink formulations for high-throughput production of optoelectronic devices; it also paves a path for "dual-mode" devices with both PV and LED functionalities.
RESUMEN
Embedding metal-halide perovskite particles within an insulating host matrix has proven to be an effective strategy for revealing the outstanding luminescence properties of perovskites as an emerging class of light emitters. Particularly, unexpected bright green emission observed in a nominally pure zero-dimensional cesium-lead-bromide perovskite (Cs4PbBr6) has triggered intensive research in better understanding the serendipitous incorporation of emissive guest species within the Cs4PbBr6 host. However, a limited controllability over such heterostructural configurations in conventional solution-based synthesis methods has limited the degree of freedom in designing synthesis routes for accessing different structural and compositional configurations of these host-guest species. In this study, we provide means of enhancing the luminescence properties in the nominal Cs4PbBr6 powder through a guided heterostructural configuration engineering enabled by solid-state mechanochemical synthesis. Realized by an in-depth study on time-dependent evaluation of optical and structural properties during the synthesis of Cs4PbBr6, our target-designed synthesis protocol to promote the endotaxial formation of Cs4PbBr6/CsPbBr3 heterostructures provides key insights for understanding and designing kinetics-guided syntheses of highly luminescent perovskite emitters for light-emitting applications.
RESUMEN
Many technologically relevant materials for advanced energy storage and catalysis feature reduced transition-metal (TM) oxides that are often nontrivial to prepare because of the need to control the reducing nature of the atmosphere in which they are synthesized. Herein, we show that an abâ initio predictive synthesis strategy can be used to produce multi-gram-scale products of various MgVx Oy -type phases (δ-MgV2 O5 , spinel MgV2 O4 , and MgVO3 ) containing V3+ or V4+ relevant for Mg-ion battery cathodes. Characterization of these phases using 25 Mg solid-state NMR spectroscopy illustrates the potential of 25 Mg NMR for studying reversible magnesiation and local charge distributions. Rotor-assisted population transfer (RAPT) is used as a much-needed signal-to-noise enhancement technique. The abâ initio guided synthesis method is seen as a step forward towards a predictive synthesis strategy for targeting specific complex TM oxides with variable oxidation states of technological importance.
RESUMEN
P2-layered sodium-ion battery (NIB) cathodes are a promising class of Na-ion electrode materials with high Na+ mobility and relatively high capacities. In this work, we report the structural changes that take place in P2-Na0.67[Mg0.28Mn0.72]O2. Using ex situ X-ray diffraction, Mn K-edge extended X-ray absorption fine structure, and 23Na NMR spectroscopy, we identify the bulk phase changes along the first electrochemical charge-discharge cycle-including the formation of a high-voltage "Z phase", an intergrowth of the OP4 and O2 phases. Our ab initio transition state searches reveal that reversible Mg2+ migration in the Z phase is both kinetically and thermodynamically favorable at high voltages. We propose that Mg2+ migration is a significant contributor to the observed voltage hysteresis in Na0.67[Mg0.28Mn0.72]O2 and identify qualitative changes in the Na+ ion mobility.
RESUMEN
BACKGROUND AND PURPOSE: Serum insulin-like growth factor-1 (IGF-1) is known to have a neuroprotective effect. This study aimed to determine the effects of serum IGF-1 on the severity and clinical outcome of acute ischemic stroke (AIS). METHODS: This study included 446 patients with AIS who were admitted to Hallym University Sacred Heart Hospital within 7 days of stroke onset from February 2014 to June 2017. Serum IGF-1 levels were measured within 24 hours of admission. Stroke severity was measured using the National Institutes of Health Stroke Scale (NIHSS) score at admission, and the functional outcome at 3 months after symptom onset was assessed using the modified Rankin Scale score. The effects of serum IGF-1 levels on stroke severity and 3-month functional outcomes were analyzed using multivariate logistic regression analysis. RESULTS: This study evaluated 379 patients with AIS (age 67.2±12.6 years, mean±standard deviation; 59.9% males) after excluding 67 patients who had a history of previous stroke (n=25) or were lost to follow-up at 3 months (n=42). After adjusting for clinically relevant covariates, a higher serum IGF-1 level was associated with a lower NIHSS score at admission (adjusted odds ratio=0.44, 95% confidence interval=0.24-0.80, p=0.01), while there was no significant association at 3 months. CONCLUSIONS: This study showed that a higher serum IGF-1 level is associated with a lower NIHSS score at admission but not at 3 months. Further studies are required to clarify the usefulness of the serum IGF-1 level as a prognostic marker for ischemic stroke.
RESUMEN
Lead halide perovskites are promising semiconductors for light-emitting applications because they exhibit bright, bandgap-tunable luminescence with high colour purity1,2. Photoluminescence quantum yields close to unity have been achieved for perovskite nanocrystals across a broad range of emission colours, and light-emitting diodes with external quantum efficiencies exceeding 20 per cent-approaching those of commercial organic light-emitting diodes-have been demonstrated in both the infrared and the green emission channels1,3,4. However, owing to the formation of lower-bandgap iodide-rich domains, efficient and colour-stable red electroluminescence from mixed-halide perovskites has not yet been realized5,6. Here we report the treatment of mixed-halide perovskite nanocrystals with multidentate ligands to suppress halide segregation under electroluminescent operation. We demonstrate colour-stable, red emission centred at 620 nanometres, with an electroluminescence external quantum efficiency of 20.3 per cent. We show that a key function of the ligand treatment is to 'clean' the nanocrystal surface through the removal of lead atoms. Density functional theory calculations reveal that the binding between the ligands and the nanocrystal surface suppresses the formation of iodine Frenkel defects, which in turn inhibits halide segregation. Our work exemplifies how the functionality of metal halide perovskites is extremely sensitive to the nature of the (nano)crystalline surface and presents a route through which to control the formation and migration of surface defects. This is critical to achieve bandgap stability for light emission and could also have a broader impact on other optoelectronic applications-such as photovoltaics-for which bandgap stability is required.
RESUMEN
Conventional solution-processing techniques such as the spin-coating method have been used successfully to reveal excellent properties of organic-inorganic halide perovskites (OHPs) for optoelectronic devices such as solar cell and light-emitting diode, but it is essential to explore other deposition techniques compatible with large-scale production. Single-source flash evaporation technique, in which a single source of materials of interest is rapidly heated to be deposited in a few seconds, is one of the candidate techniques for large-scale thin film deposition of OHPs. In this work, we investigated the reliability and controllability of the single-source flash evaporation technique for methylammonium lead iodide (MAPbI3) perovskite. In-depth statistical analysis was employed to demonstrate that the MAPbI3 films prepared via the flash evaporation have an ultrasmooth surface and uniform thickness throughout the 4-inch wafer scale. We also show that the thickness and grain size of the MAPbI3 film can be controlled by adjusting the amount of the source and number of deposition steps. Finally, the excellent large-area uniformity of the physical properties of the deposited thin films can be transferred to the uniformity in the device performance of MAPbI3 photodetectors prepared by flash evaporation which exhibited the responsivity of 0.2 A/W and detectivity of 3.82 × 1011 Jones.