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1.
Nature ; 626(7997): 105-110, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38297175

RESUMEN

Silicon solar cells are a mainstay of commercialized photovoltaics, and further improving the power conversion efficiency of large-area and flexible cells remains an important research objective1,2. Here we report a combined approach to improving the power conversion efficiency of silicon heterojunction solar cells, while at the same time rendering them flexible. We use low-damage continuous-plasma chemical vapour deposition to prevent epitaxy, self-restoring nanocrystalline sowing and vertical growth to develop doped contacts, and contact-free laser transfer printing to deposit low-shading grid lines. High-performance cells of various thicknesses (55-130 µm) are fabricated, with certified efficiencies of 26.06% (57 µm), 26.19% (74 µm), 26.50% (84 µm), 26.56% (106 µm) and 26.81% (125 µm). The wafer thinning not only lowers the weight and cost, but also facilitates the charge migration and separation. It is found that the 57-µm flexible and thin solar cell shows the highest power-to-weight ratio (1.9 W g-1) and open-circuit voltage (761 mV) compared to the thick ones. All of the solar cells characterized have an area of 274.4 cm2, and the cell components ensure reliability in potential-induced degradation and light-induced degradation ageing tests. This technological progress provides a practical basis for the commercialization of flexible, lightweight, low-cost and highly efficient solar cells, and the ability to bend or roll up crystalline silicon solar cells for travel is anticipated.

2.
Proc Natl Acad Sci U S A ; 120(38): e2310163120, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37703282

RESUMEN

Callus is a reprogrammed cell mass involved in plant regeneration and gene transformation in crop engineering. Pluripotent callus cells develop into fertile shoots through shoot regeneration. The molecular basis of the shoot regeneration process in crop callus remains largely elusive. This study pioneers the exploration of the spatial transcriptome of tomato callus during shoot regeneration. The findings reveal the presence of highly heterogeneous cell populations within the callus, including epidermis, vascular tissue, shoot primordia, inner callus, and outgrowth shoots. By characterizing the spatially resolved molecular features of shoot primordia and surrounding cells, specific factors essential for shoot primordia formation are identified. Notably, chlorenchyma cells, enriched in photosynthesis-related processes, play a crucial role in promoting shoot primordia formation and subsequent shoot regeneration. Light is shown to promote shoot regeneration by inducing chlorenchyma cell development and coordinating sugar signaling. These findings significantly advance our understanding of the cellular and molecular aspects of shoot regeneration in tomato callus and demonstrate the immense potential of spatial transcriptomics in plant biology.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Transcriptoma , Células Epiteliales , Perfilación de la Expresión Génica , Regeneración/genética
3.
J Pathol ; 263(1): 47-60, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38389501

RESUMEN

Liver kinase B1 (Lkb1), encoded by serine/threonine kinase (Stk11), is a serine/threonine kinase and tumor suppressor that is strongly implicated in Peutz-Jeghers syndrome (PJS). Numerous studies have shown that mesenchymal-specific Lkb1 is sufficient for the development of PJS-like polyps in mice. However, the cellular origin and components of these Lkb1-associated polyps and underlying mechanisms remain elusive. In this study, we generated tamoxifen-inducible Lkb1flox/flox;Myh11-Cre/ERT2 and Lkb1flox/flox;PDGFRα-Cre/ERT2 mice, performed single-cell RNA sequencing (scRNA-seq) and imaging-based lineage tracing, and aimed to investigate the cellular complexity of gastrointestinal polyps associated with PJS. We found that Lkb1flox/+;Myh11-Cre/ERT2 mice developed gastrointestinal polyps starting at 9 months after tamoxifen treatment. scRNA-seq revealed aberrant stem cell-like characteristics of epithelial cells from polyp tissues of Lkb1flox/+;Myh11-Cre/ERT2 mice. The Lkb1-associated polyps were further characterized by a branching smooth muscle core, abundant extracellular matrix deposition, and high immune cell infiltration. In addition, the Spp1-Cd44 or Spp1-Itga8/Itgb1 axes were identified as important interactions among epithelial, mesenchymal, and immune compartments in Lkb1-associated polyps. These characteristics of gastrointestinal polyps were also demonstrated in another mouse model, tamoxifen-inducible Lkb1flox/flox;PDGFRα-Cre/ERT2 mice, which developed obvious gastrointestinal polyps as early as 2-3 months after tamoxifen treatment. Our findings further confirm the critical role of mesenchymal Lkb1/Stk11 in gastrointestinal polyposis and provide novel insight into the cellular complexity of Lkb1-associated polyp biology. © 2024 The Pathological Society of Great Britain and Ireland.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Síndrome de Peutz-Jeghers , Animales , Ratones , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/patología , Proteínas Serina-Treonina Quinasas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Análisis de Secuencia de ARN , Serina , Tamoxifeno/farmacología
4.
Br J Haematol ; 204(4): 1344-1353, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479427

RESUMEN

This study investigates the potential utility of IKZF1 deletion as an additional high-risk marker for paediatric acute lymphoblastic leukaemia (ALL). The prognostic impact of IKZF1 status, in conjunction with minimal/measurable residual disease (MRD), was evaluated within the MRD-guided TPOG-ALL-2013 protocol using 412 newly diagnosed B-ALL patients aged 1-18. IKZF1 status was determined using multiplex ligation-dependent probe amplification. IKZF1 deletions, when co-occurring with CDKN2A, CDKN2B, PAX5 or PAR1 region deletions in the absence of ERG deletions, were termed IKZF1plus. Both IKZF1 deletion (14.6%) and IKZF1plus (7.8%) independently predicted poorer outcomes in B-ALL. IKZF1plus was observed in 4.1% of Philadelphia-negative ALL, with a significantly lower 5-year event-free survival (53.9%) compared to IKZF1 deletion alone (83.8%) and wild-type IKZF1 (91.3%) (p < 0.0001). Among patients with Day 15 MRD ≥0.01%, provisional high-risk patients with IKZF1plus exhibited the worst outcomes in event-free survival (42.0%), relapse-free survival (48.0%) and overall survival (72.7%) compared to other groups (p < 0.0001). Integration of IKZF1plus and positive Day 15 MRD identified a subgroup of Philadelphia-negative B-ALL with a 50% risk of relapse. This study highlights the importance of assessing IKZF1plus alongside Day 15 MRD positivity to identify patients at increased risk of adverse outcomes, potentially minimizing overtreatment.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Niño , Humanos , Eliminación de Gen , Factor de Transcripción Ikaros/genética , Recurrencia Local de Neoplasia , Neoplasia Residual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Pronóstico , Medición de Riesgo , Factores de Transcripción , Lactante , Preescolar , Adolescente
5.
Bioconjug Chem ; 35(5): 575-581, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38456602

RESUMEN

Living microbial therapies have been proposed as a course of action for a variety of diseases. However, problematic interactions between the host immune system and the microbial organism present significant clinical concerns. Previously, we developed a genetically encoded superhydrophilic zwitterionic peptide, termed EKP, to mimic low-immunogenic zwitterionic materials, which have been used for the chemical modification of biologics such as protein and nucleic acid drugs to increase their in vivo circulation time and reduce their immunogenicity. Herein, we demonstrate the protective effects of the EKP polypeptide genetically cloaking the surface of Saccharomyces cerevisiae as a model microbe in both in vitro and in vivo systems. First, we show that EKP peptide cloaking suppresses the interactions between yeast cells and their specific antibodies, thereby illustrating its cloaking behavior. Then, we examine the in vitro interactions between EKP peptide surface cloaked yeast cells and murine macrophage cells, which exhibit phagocytotic behavior in the presence of foreign microbes. Our results indicate that EKP cloaking suppresses macrophage interactions and thus reduces phagocytosis. Furthermore, EKP cloaked yeast cells demonstrate a prolonged circulation time in mice in vivo.


Asunto(s)
Péptidos , Saccharomyces cerevisiae , Animales , Ratones , Péptidos/química , Péptidos/farmacología , Fagocitosis/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología
6.
J Exp Bot ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39021198

RESUMEN

Grain filling is a critical process for improving crop production under adverse conditions caused by climate change. Here, using a quantitative method, we quantified post-anthesis source-sink relationships of a large data set to assess the contribution of remobilized pre-anthesis assimilates to grain growth for both biomass and nitrogen. The data set came from 13 years' semi-controlled field experimentation, in which six bread wheat genotypes were grown at plot scale under contrasting temperature, water, and nitrogen regimes. On average, grain biomass was ~10% higher than post-anthesis aboveground biomass accumulation across regimes and genotypes. Overall, the estimated relative contribution (%) of remobilized assimilates to grain biomass became increasingly significant with increasing stress intensity, ranging from virtually nil to 100%. This percentage was altered more by water and nitrogen regimes than by temperature, indicating the greater impact of water or nitrogen regimes relative to high temperatures under our experimental conditions. Relationships between grain nitrogen demand and post-anthesis nitrogen uptake were generally insensitive to environmental conditions, as there was always significant remobilization of nitrogen from vegetative organs, which helped to stabilize the amount of grain nitrogen. Moreover, variations in the relative contribution of remobilized assimilates with environmental variables were genotype-dependent. Our analysis provides an overall picture of post-anthesis source-sink relationships and pre-anthesis assimilate contributions to grain filling across (non-)environmental factors, and highlights that designing wheat adaption to climate change should account for complex multi-factor interactions.

7.
Opt Lett ; 49(13): 3572-3575, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950212

RESUMEN

We demonstrate the post-induction of high-quality microcavities on a silicon photonic crystal (PC) waveguide by integrating a few-layer GaSe crystal, which promises efficient on-chip optical frequency conversions. The integration of GaSe shifts the dispersion bands of the PC waveguide mode into the bandgap, resulting in localized modes confined by the bare PC waveguides. Thanks to the small contrast of refractive index at the boundaries of the microcavity, it is reliable to obtain quality factors exceeding 104. With the enhanced light-GaSe interaction by the microcavity modes and GaSe's high second-order nonlinearity, remarkable second-harmonic generation (SHG) and sum-frequency generation (SFG) are achieved with continuous-wave (CW) lasers.

8.
Phys Rev Lett ; 132(7): 073802, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38427883

RESUMEN

The exotic physics associated with exceptional points (EPs) is always under the scrutiny of theoretical and experimental science. Recently, considerable effort has been invested in the combination of nonlinearity and non-Hermiticity. The concept of nonlinear EPs (NEPs) has been introduced, which can avoid the loss of completeness of the eigenbasis in dynamics while retaining the key features of linear EPs. Here, we present the first direct experimental demonstration of a NEP based on two non-Hermition coupled circuit resonators combined with a nonlinear saturable gain. At the NEP, the response of the eigenfrequency to perturbations demonstrates a third-order root law and the eigenbasis of the Hamiltonian governing the system dynamics is still complete. Our results bring this counterintuitive aspect of the NEP to light and possibly open new avenues for applications.

9.
Reprod Biomed Online ; 48(4): 103685, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38324980

RESUMEN

RESEARCH QUESTION: What role does programmed cell death 4 (PDCD4) play in premature ovarian insufficiency (POI)? DESIGN: A PDCD4 gene knockout (PDCD4-/-) mouse model was constructed, a POI mouse model was established similar to human POI with 4-vinylcyclohexene dioxide (VCD), a PDCD4-overexpressed adenovirus was designed and the regulatory role in POI in vitro and in vivo was investigated. RESULTS: PDCD4 expression was significantly increased in the ovarian granulosa cells of patients with POI (P ≤ 0.002 protein and mRNA) and mice with VCD-induced POI (P < 0.001 protein expression in both mouse ovaries and granulosa cells). In POI-induced mice model, PDCD4 knockouts significantly increased anti-Müllerian hormone, oestrodiol and numbers of developing follicles, and the PI3K-AKT-Bcl2/Bax signalling pathway is involved in it. CONCLUSION: The expression and regulation of PDCD4 significantly affects the POI pathology in a mouse model. This effect is closely related to the regulation of Bcl2/Bax and the activation of the PI3K-AKT signalling pathway.


Asunto(s)
Ciclohexenos , Insuficiencia Ovárica Primaria , Animales , Femenino , Humanos , Ratones , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Modelos Animales de Enfermedad , Fosfatidilinositol 3-Quinasas/metabolismo , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas de Unión al ARN/genética
10.
Eur J Clin Microbiol Infect Dis ; 43(6): 1213-1220, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38613707

RESUMEN

PURPOSE: The COVID-19 pandemic has notably altered the infection dynamics of various pathogens. This study aimed to evaluate the pandemic's impact on the infection spectrum of Mycoplasma pneumoniae (M. pneumoniae) among children with community acquired pneumonia (CAP). METHODS: We enrolled pediatric CAP patients admitted to a tertiary hospital in southwest China to compare the prevalence and characteristics of M. pneumoniae infections before (2018-2019) and during (2020-2022) the COVID-19 pandemic. Detection of M. pneumoniae IgM antibodies in serum were conducted using either indirect immunofluorescence or passive agglutination methods. RESULTS: The study included 1505 M. pneumoniae-positive and 3160 M. pneumoniae-negative CAP patients. Notable findings were the higher age and frequency of pneumonia-associated symptoms in M. pneumoniae-positive patients, alongside a lower male proportion and fewer respiratory co-infections. The year 2019 saw a notable increase in M. pneumoniae infections compared to 2018, followed by a decline from 2020 to 2022. The COVID-19 pandemic period witnessed significant alterations in age distribution, male proportion, and co-infections with specific pathogens in both M. pneumoniae-positive and negative patients. The M. pneumoniae infections were predominantly seasonal, peaking in autumn and winter during 2018 and 2019. Although there was a sharp drop in February 2020, the infection still peaked in cold months of 2020 and 2021. However, the typical seasonal pattern was nearly absent in 2022. CONCLUSIONS: The COVID-19 pandemic has markedly changed the infection landscape of M. pneumoniae in pediatric CAP patients, with shifts observed in infection rates, demographic profiles, co-infections, and seasonal patterns.


Asunto(s)
COVID-19 , Infecciones Comunitarias Adquiridas , Mycoplasma pneumoniae , Neumonía por Mycoplasma , Centros de Atención Terciaria , Humanos , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , China/epidemiología , Masculino , Neumonía por Mycoplasma/epidemiología , Femenino , COVID-19/epidemiología , Niño , Centros de Atención Terciaria/estadística & datos numéricos , Estudios Retrospectivos , Preescolar , Mycoplasma pneumoniae/inmunología , Lactante , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/virología , Adolescente , SARS-CoV-2 , Prevalencia , Inmunoglobulina M/sangre , Hospitalización
11.
Infection ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848016

RESUMEN

PURPOSE: The COVID-19 pandemic has altered the infection dynamics of numerous pathogens. This study aimed to elucidate its impact on Streptococcus pneumoniae (S. pneumoniae) infections in children with community acquired pneumonia (CAP). METHODS: A retrospective analysis was conducted in pediatric CAP patients admitted before (2018-2019) and during (2020-2022) the COVID-19 pandemic. The epidemiology and antimicrobial resistance (AMR) patterns of S. pneumoniae were compared to reveal the impact of the pandemic. RESULTS: A total of 968 S. pneumoniae-associated pediatric CAP patients were enrolled. Although the positivity rate and gender of patients were stable across both periods, the age notably increased in 2021 and 2022. Additionally, significant changes were observed in the co-infections with several pathogens and the resistance rates to certain antibiotics during the COVID-19 pandemic. The resistance rate to clindamycin and quinupristin-dalfopristin increased, whereas the resistance rate to tetracycline, trimethoprim-sulfamethoxazole, telithromycin, and proportion of multi-drug resistant isolates decreased. The number of S. pneumoniae strains and resistant isolates exhibited similar seasonal patterns in 2018 and 2019, peaking in November or December with another minor peak in March or April. During the COVID-19 pandemic, there was a sharp decrease in February 2020 and no resurgence was observed at the end of 2022. Additionally, the minor peak was absent in 2020 and shifted to other months in 2021 and 2022. CONCLUSIONS: The COVID-19 pandemic has markedly altered the infection spectrum of S. pneumoniae in pediatric CAP patients, as evidenced by shifts in the age of patients, respiratory co-infections, AMR patterns, and seasonal trends.

12.
Bioorg Chem ; 148: 107463, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38776649

RESUMEN

Thrombosis leads to elevated mortality rates and substantial medical expenses worldwide. Human factor IXa (HFIXa) protease is pivotal in tissue factor (TF)-mediated thrombin generation, and represents a promising target for anticoagulant therapy. We herein isolated novel DNA aptamers that specifically bind to HFIXa through systematic evolution of ligands by exponential enrichment (SELEX) method. We identified two distinct aptamers, seq 5 and seq 11, which demonstrated high binding affinity to HFIXa (Kd = 74.07 ± 2.53 nM, and 4.93 ± 0.15 nM, respectively). Computer software was used for conformational simulation and kinetic analysis of DNA aptamers and HFIXa binding. These aptamers dose-dependently prolonged activated partial thromboplastin time (aPTT) in plasma. We further rationally optimized the aptamers by truncation and site-directed mutation, and generated the truncated forms (Seq 5-1t, Seq 11-1t) and truncated-mutated forms (Seq 5-2tm, Seq 11-2tm). They also showed good anticoagulant effects. The rationally and structurally designed antidotes (seq 5-2b and seq 11-2b) were competitively bound to the DNA aptamers and effectively reversed the anticoagulant effect. This strategy provides DNA aptamer drug-antidote pair with effective anticoagulation and rapid reversal, developing advanced therapies by safe, regulatable aptamer drug-antidote pair.


Asunto(s)
Antídotos , Aptámeros de Nucleótidos , Factor IXa , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/farmacología , Humanos , Factor IXa/antagonistas & inhibidores , Factor IXa/metabolismo , Antídotos/farmacología , Antídotos/química , Antídotos/síntesis química , Relación Dosis-Respuesta a Droga , Anticoagulantes/farmacología , Anticoagulantes/química , Relación Estructura-Actividad , Estructura Molecular , Técnica SELEX de Producción de Aptámeros
13.
BMC Psychiatry ; 24(1): 165, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413912

RESUMEN

BACKGROUND: Mood disorders are strongly associated with melatonin disturbances. However, it is unclear whether there is a difference in melatonin concentrations and melatonin circadian rhythm profiles between depression and bipolar disorder. In addition, the relationship between anhedonia, a common symptom of affective disorders, and its melatonin circadian rhythm remains under-investigated. METHODS: Thirty-four patients with depression disorder, 20 patients diagnosed with bipolar disorder and 21 healthy controls participated in this study. The Revised Physical Anhedonia Scale (RPAS) was performed to assess anhedonia. Saliva samples were collected from all subjects at fixed time points (a total of 14 points) in two consecutive days for measuring the melatonin concentrations to fit circadian rhythms of subjects. Melatonin circadian rhythms were compared between the three groups using ANOVA. Partial correlation analysis and linear regression analysis were used to explore the correlation between melatonin rhythm variables and anhedonia. RESULTS: We found that the peak phase of melatonin in the depression group was significantly advanced compared to the control group (P < 0.001) and the bipolar disorder group (P = 0.004). The peak phase of melatonin and RPAS showed a negative correlation (P = 0.003) in depression patients, which was also demonstrated in the multiple linear regression model (B=-2.47, P = 0.006). CONCLUSIONS: These results suggest that circadian rhythms of melatonin are differentiated in depression and bipolar disorder and correlate with anhedonia in depression. Future research needs to explore the neurobiological mechanisms linking anhedonia and melatonin circadian rhythms in depressed patients.


Asunto(s)
Melatonina , Trastornos del Humor , Humanos , Anhedonia , Estudios Transversales , Ritmo Circadiano
14.
Nucleic Acids Res ; 50(5): e26, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35191504

RESUMEN

Alternative polyadenylation (APA) plays an important role in gene regulation. With the recent application of novel sequencing technology in APA profiling, an ever-increasing number of APA genes/sites have been identified. However, the phenotypic relevance of most of these APA isoforms remains elusive, which is largely due to the lack of a convenient genetics tool for APA interference. To address this issue, herein, an efficient method is developed based on the CRISPR-dCas13 system, termed as CRISPR-iPAS. Out of eight different dCas13 proteins, Porphyromonas gulae (Pgu) dCas13b, is identified as the most effective one in blocking the usage of the polyadenylation site (PAS). With guide RNAs targeting at core regulatory elements, dPguCas13b enabled APA regulation of endogenous genes with different APA types, including tandem 3'UTR, alternative terminal exon, as well as intronic PAS. Finally, we demonstrated that the proposed APA perturbation tool could be used to investigate the functional relevance of APA isoforms.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Técnicas Genéticas , Poliadenilación , Regiones no Traducidas 3' , Regulación de la Expresión Génica , Intrones/genética
15.
Pediatr Hematol Oncol ; : 1-10, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867542

RESUMEN

Patients with newly diagnosed hematological malignancies often present with a considerable cellular burden, leading to complications including hyperkalemia. However, pseudohyperkalemia, arising from in vitro cell lysis, can pose challenges in clinical practice. Although pseudohyperkalemia is frequently reported in adult hematological malignancies, its occurrence in pediatric patients is underreported, and its incidence in this demographic remains unclear. We retrospectively reviewed the medical records of pediatric patients who received a new diagnosis of hematological malignancies from 2011 to 2022 at Taichung Veterans General Hospital. Hyperkalemia was defined by a serum or plasma potassium level exceeding 5.5 mEq/L. Pseudohyperkalemia was defined by 1) a potassium decrease of over 1 mEq/L in within 4 h without intervention or 2) the absence of electrocardiography changes indicative of hyperkalemia. Cases with apparent red blood cell hemolysis were excluded. A total of 157 pediatric patients with a new diagnosis of hematological malignancies were included, 14 of whom exhibited hyperkalemia. Among these 14 cases, 7 cases (4.5%) were of pseudohyperkalemia. This rate increased to 21.2% in patients with initial hyperleukocytosis. Pseudohyperkalemia was associated with a higher initial white blood cell count and lower serum sodium level. All episodes of pseudohyperkalemia occurred in the pediatric emergency department, where samples were obtained as plasma, whereas all true hyperkalemia cases were observed in the ordinary ward or intensive care unit, where samples were obtained as serum. Timely recognition of pseudohyperkalemia is crucial to avoiding unnecessary potassium-lowering interventions in pediatric patients with newly diagnosed hematological malignancies.

16.
Nano Lett ; 23(11): 4931-4937, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37265387

RESUMEN

Magnetic skyrmions are real-space topological spin textures, which have attracted increasing attention from the nanospintronics community. Toward functional skyrmionics, the efficient manipulation of skyrmions is a prerequisite, which has been successfully demonstrated through electrical, thermal, optical, and other means. Here, through integrating an interfacially asymmetric Ta/CoFeB/MgO multilayer with an on-chip wire that induces Oersted fields and their gradients, we show experimentally the generation and topology-dependent motion of Néel type skyrmions at room temperature. In particular, an opposite longitudinal motion for skyrmions with opposite topological charges along the gradient direction is observed. Through comparing with the well-known Stern-Gerlach experiment, in which the splitting of atomic spins under magnetic field gradients was observed, our work identifies another interesting aspect of the topological character of skyrmions. The present study could also be implemented for designing novel on-chip skyrmionic devices in which the manipulation of skyrmions cannot be done by electrical means.

17.
Angew Chem Int Ed Engl ; 63(25): e202402565, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38588114

RESUMEN

Atomically precise ~1-nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic-ligand-protected (~1-nm) Pt23 NCs precisely characterized with mass spectrometry and single-crystal X-ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge -layer distribution in the sandwich-like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d-band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532-nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications.

18.
Angew Chem Int Ed Engl ; : e202407518, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38752452

RESUMEN

Gold nanoclusters exhibiting concomitant photothermy (PT) and photoluminescence (PL) under near-infrared (NIR) light irradiation are rarely reported, and some fundamental issues remain unresolved for such materials. Herein, we concurrently synthesized two novel rod-shaped Au nanoclusters, Au52(PET)32 and Au66(PET)38 (PET = 2-phenylethanethiolate), and precisely revealed that their kernels were 4 × 4 × 6 and 5 × 4 × 6 face-centered cubic (fcc) structures, respectively, based on the numbers of Au layers in the [100], [010], and [001] directions. Following the structural growth mode from Au52(PET)32 to Au66(PET)38, we predicted six more novel nanoclusters. The concurrent synthesis provides rational comparison of the two nanoclusters on the stability, absorption, emission and photothermy, and reveals the aspect ratio-related properties. An interesting finding is that the two nanoclusters exhibit concomitant PT and PL under 785 nm light irradiation, and the PT and PL are in balance, which was explained by the qualitative evaluation of the radiative and non-radiative rates. The ligand effects on PT and PL were also investigated.

19.
Cancer ; 129(5): 790-802, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36537587

RESUMEN

BACKGROUND: This study analyzed data from two consecutive protocols for children newly diagnosed with acute lymphoblastic leukemia (ALL) to determine the clinical impact of minimal/measurable residual disease (MRD) and recently identified tumor genetic subtypes. METHODS: Genetic subtypes were determined by sequential approaches including DNA indexing, reverse transcriptase-polymerase chain reaction, multiplex ligation-dependent probe amplification, and RNA-sequencing. MRD was assessed by flow cytometry. The Taiwan Pediatric Oncology Group TPOG-ALL-2013 study enrolled patients who received MRD-directed therapy. RESULTS: The 5-year event-free survival (EFS) and overall survival rates in the 2013 cohort were 77.8% and 86.9% compared to those of the 2002 cohort, which were 62.4% and 76.5%. Among patients treated with MRD-guided therapy, those with ETV6-RUNX1 fusion and high hyperdiploidy had the highest 5-year EFS (91.4% and 89.6%, respectively). The addition of dasatinib improved outcomes in patients with BCR-ABL1 ALL. Recently identified subtypes like DUX4-rearranged, ZNF384-rearranged, MEF2D-rearranged, and PAX5alt subtypes were frequently positive for MRD after remission induction, and these patients consequently received intensified chemotherapy. Treatment intensification according to the MRD improved the outcomes of patients presenting DUX4 rearrangements. In high-risk or very-high-risk subtypes, the TPOG-ALL-2013 regimen did not confer significant improvements compared to TPOG-ALL-2002, and the outcomes of BCR-ABL1-like, MEF2D-rearranged, and KMT2A-rearranged ALL subtypes (in addition to those of T-cell ALL) were not sufficiently good. Novel agents or approaches are needed to improve the outcomes for these patients. CONCLUSIONS: The TPOG-ALL-2013 study yielded outcomes superior to those of patients treated in the preceding TPOG-ALL-2002 study. This study provides important data to inform the design of future clinical trials in Taiwan. PLAIN LANGUAGE SUMMARY: MRD-directed therapy improved the outcomes for pediatric ALL, especially standard-risk patients. Genomic analyses and MRD might be used together for risk-directed therapy of childhood ALL. Our work provides important data to inform the design of future clinical trials in Taiwan.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras , Niño , Humanos , Neoplasia Residual/genética , Neoplasia Residual/diagnóstico , Pronóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Dasatinib/uso terapéutico , Inducción de Remisión
20.
Bioconjug Chem ; 34(1): 85-91, 2023 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-36173879

RESUMEN

Hydrophobic moieties of amphiphilic DNAs can help DNAs penetrate cell membranes, but the conjugation of hydrophobic moieties to DNAs in solution phase remains challenging. Herein we report a solution-phase synthesis method to conjugate hydrophobic molecules to DNAs. This method is simple and efficient. The resulted amphiphilic DNAs can spontaneously assemble into micelles, which may serve as nanocarriers for cellular delivery of nucleic acids and water-insoluble drugs.


Asunto(s)
ADN , Micelas , ADN/química , Interacciones Hidrofóbicas e Hidrofílicas
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