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1.
Nat Mater ; 22(12): 1463-1469, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37828101

RESUMEN

Twist angle between two-dimensional layers is a critical parameter that determines their interfacial properties, such as moiré excitons and interfacial ferro-electricity. To achieve better control over these properties for fundamental studies and various applications, considerable efforts have been made to manipulate twist angle. However, due to mechanical limitations and the inevitable formation of incommensurate regions, there remains a challenge in attaining perfect alignment of crystalline orientation. Here we report a thermally induced atomic reconstruction of randomly stacked transition metal dichalcogenide multilayers into fully commensurate heterostructures with zero twist angle by encapsulation annealing, regardless of twist angles of as-stacked samples and lattice mismatches. We also demonstrate the selective formation of R- and H-type fully commensurate phases with a seamless lateral junction using chemical vapour-deposited transition metal dichalcogenides. The resulting fully commensurate phases exhibit strong photoluminescence enhancement of the interlayer excitons, even at room temperature, due to their commensurate structure with aligned momentum coordinates. Our work not only demonstrates a way to fabricate zero-twisted, two-dimensional bilayers with R- and H-type configurations, but also provides a platform for studying their unexplored properties.

2.
Pulm Pharmacol Ther ; 80: 102189, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36634813

RESUMEN

Throughout the recent COVID-19 pandemic, South Korea led national efforts to develop vaccines and therapeutics for SARS-CoV-2. The project proceeded as follows: 1) evaluation system setup (including Animal Biosafety Level 3 (ABSL3) facility alliance, standardized nonclinical evaluation protocol, and laboratory information management system), 2) application (including committee review and selection), and 3) evaluation (including expert judgment and reporting). After receiving 101 applications, the selection committee reviewed pharmacokinetics, toxicity, and efficacy data and selected 32 final candidates. In the nonclinical efficacy test, we used golden Syrian hamsters and human angiotensin-converting enzyme 2 transgenic mice under a cytokeratin 18 promoter to evaluate mortality, clinical signs, body weight, viral titer, neutralizing antibody presence, and histopathology. These data indicated eight new drugs and one repositioned drug having significant efficacy for COVID-19. Three vaccine and four antiviral drugs exerted significant protective activities against SARS-CoV-2 pathogenesis. Additionally, two anti-inflammatory drugs showed therapeutic effects on lung lesions and weight loss through their mechanism of action but did not affect viral replication. Along with systematic verification of COVID-19 animal models through large-scale studies, our findings suggest that ABSL3 multicenter alliance and nonclinical evaluation protocol standardization can promote reliable efficacy testing against COVID-19, thus expediting medical product development.


Asunto(s)
COVID-19 , Animales , Cricetinae , Ratones , Humanos , SARS-CoV-2 , Pandemias , Anticuerpos Neutralizantes , Mesocricetus , Modelos Animales de Enfermedad
3.
Nano Lett ; 21(20): 8554-8562, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34623164

RESUMEN

As a 3D topological insulator, bismuth selenide (Bi2Se3) has potential applications for electrically and optically controllable magnetic and optoelectronic devices. Understanding the coupling with its topological phase requires studying the interactions of carriers with the lattice on time scales down to the subpicosecond regime. Here, we investigate the ultrafast carrier-induced lattice contractions and interlayer modulations in Bi2Se3 thin films by time-resolved diffraction using an X-ray free-electron laser. The lattice contraction depends on the carrier concentration and is followed by an interlayer expansion accompanied by oscillations. Using density functional theory and the Lifshitz model, the initial contraction can be explained by van der Waals force modulation of the confined free carrier layers. Our theoretical calculations suggest that the band inversion, related to a topological phase transition, is modulated by the expansion of the interlayer distance. These results provide insights into the topological phase control by light-induced structural change on ultrafast time scales.

4.
Proc Natl Acad Sci U S A ; 111(2): 599-604, 2014 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24379365

RESUMEN

Sodium ion batteries offer promising opportunities in emerging utility grid applications because of the low cost of raw materials, yet low energy density and limited cycle life remain critical drawbacks in their electrochemical operations. Herein, we report a vanadium-based ortho-diphosphate, Na7V4(P2O7)4PO4, or VODP, that significantly reduces all these drawbacks. Indeed, VODP exhibits single-valued voltage plateaus at 3.88 V vs. Na/Na(+) while retaining substantial capacity (>78%) over 1,000 cycles. Electronic structure calculations reveal that the remarkable single plateau and cycle life originate from an intermediate phase (a very shallow voltage step) that is similar both in the energy level and lattice parameters to those of fully intercalated and deintercalated states. We propose a theoretical scheme in which the reaction barrier that arises from lattice mismatches can be evaluated by using a simple energetic consideration, suggesting that the presence of intermediate phases is beneficial for cell kinetics by buffering the differences in lattice parameters between initial and final phases. We expect these insights into the role of intermediate phases found for VODP hold in general and thus provide a helpful guideline in the further understanding and design of battery materials.


Asunto(s)
Difosfatos/química , Suministros de Energía Eléctrica , Compuestos de Vanadio/química , Cristalografía , Electroquímica , Cinética , Modelos Teóricos , Difracción de Rayos X
5.
J Am Chem Soc ; 137(22): 7210-6, 2015 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-26000786

RESUMEN

Various dry sorbents have been lately introduced as promising media to capture carbon dioxide (CO2). However, it is still desirable to further improve their performance in diverse aspects, and high temperature selectivity of CO2 over other gases is clearly one of them. Here, we report a co-assembly approach to turn nonporous melamine resin to a highly ordered mesoporous polymeric network (space group: Im3̅m) containing high nitrogen content (∼18 at%). This mesoporous network shows anomalously increasing CO2/N2 selectivity with temperature rise, with the selectivity at 323 K reaching 117 (Henry method). This selectivity behavior is attributed to a combined effect of the high nitrogen content allowing for high binding affinity with CO2 and well-defined mesopores (2.5-2.9 nm) accelerating release of N2 with temperature rise. The given orthogonal approach suggests a new direction in designing dry sorbents with excellent selectivities at high temperatures.

6.
J Am Chem Soc ; 136(19): 7018-25, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24754635

RESUMEN

Although a lot of mitochondria-targeting biothiol probes have been developed and applied to cellular imaging through thiol-induced disulfide cleavage or Michael addition reactions, relatively few probes assess mitochondrial GSH with high selectivity over Cys and Hcy and with NIR fluorescence capable of noninvasive imaging in biological samples. In order to monitor mitochondrial GSH with low background autofluorescence, we designed a heptamethine-azo conjugate as an NIR fluorescent probe by introducing a tunable lipophilic cation unit as the biomarker for mitochondria and a nitroazo group as the GSH-selective reaction site as well as the fluorescence quencher. The probe exhibited a dramatic off-on NIR fluorescence response toward GSH with high selectivity over other amino acids including Cys and Hcy. Further application to cellular imaging indicated that the probe was highly responsive to the changes of mitochondrial GSH in cells.


Asunto(s)
Compuestos Azo/química , Cisteína/análisis , Colorantes Fluorescentes/química , Glutatión/análisis , Homocisteína/análisis , Indoles/química , Células HeLa , Humanos , Microscopía Confocal , Mitocondrias/química , Imagen Óptica , Espectrometría de Fluorescencia
7.
World J Clin Cases ; 12(14): 2426-2430, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38765742

RESUMEN

BACKGROUND: Various surgical techniques have been developed to enhance the nose shapes of Asian patients. Silicone implant augmentation rhinoplasty is widely used because it is relatively easy to perform and often yields satisfactory outcomes. However, this technique may lead to complications, including ischemia, necrosis, and over-augmentation. The most appropriate management of these complications, including infection, is immediate implant removal and revision surgery once the accompanying inflammation has healed. Occasionally, the patient may experience distress from nasal deformities during the intervention period. CASE SUMMARY: Herein, we describe the case of a patient who underwent a secondary dorsal augmentation, with a folded dermofat graft harvested from the inguinal area and simultaneous implant removal, successfully preventing dimpling of the nasal deformity. CONCLUSION: This surgical method can effectively manage implant-related complications following augmentation rhinoplasty using a silicone implant and provide satisfactory patient outcomes.

8.
World J Clin Cases ; 12(3): 665-670, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38322477

RESUMEN

BACKGROUND: Porocarcinoma is a rare type of skin cancer that originates from sweat gland tumors. It is an aggressive malignant skin cancer that is difficult to diagnose clinically owing to its rarity and similarity to squamous cell carcinoma (SCC). CASE SUMMARY: This case involved a 92-year-old woman, a farmer by profession, presented with an exophytic and verrucous mass on her left palm that had formed 2 years prior and caused chronic pain and frequent bleeding. Initially, the patient was diagnosed with SCC using a punch biopsy; however, a repeat biopsy with additional immunohistochemical tests was performed for porocarcinoma. Ultimately, the patient was diagnosed with porocarcinoma and reconstruction was planned using a full-thickness skin graft. After treatment, the range of motion of the palm was preserved, and the aesthetic outcome was favorable. At 6 mo of follow-up, the patient was satisfied with the outcome. CONCLUSION: Porocarcinoma is commonly misdiagnosed as SCC; therefore, clinicians should consider porocarcinomas when evaluating mass-like lesions on the hands.

9.
Arch Craniofac Surg ; 25(1): 31-37, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38461826

RESUMEN

Orbital floor fractures are commonly encountered, but the dislocation of the eyeball into the maxillary sinus is relatively rare. When it does occur, globe dislocation can have serious consequences, including vision loss, enucleation, and orbito-ocular deformity. Immediate surgical intervention is typically attempted when possible. However, severe comorbidities and poor general health can delay necessary surgery. In this report, we present the surgical outcomes of a 70-year-old woman who received delayed treatment for traumatic eyeball dislocation into the maxillary sinus due to a subarachnoid hemorrhage and hemopneumothorax. Additionally, we propose a treatment algorithm based on our clinical experience and a review of the literature.

10.
J Pers Med ; 14(8)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39202049

RESUMEN

Anaplastic lymphoma kinase (ALK) is detected in both normal and oncological developmental tissues. Among ALK-related tumors, superficial ALK-rearranged myxoid spindle cell neoplasm (SAMS) is a rare, soft tissue tumor characterized by the immunophenotypical co-expression of CD34 and S100. Here, we describe a patient with this rare tumor and outline its clinical and radiological characteristics. A 28-year-old woman with diabetes, hypertension, and panic disorder presented with discomfort caused by a rubbery mass on the left buttock that had persisted for 10 years. Computed tomography revealed a multilobulated hypodense mass with small internal enhancing foci, posing challenges for the exact diagnosis of the lesion. The entire lesion was excised with clear resection margins. An 8.0 × 6.0 cm, well-circumscribed tumor with a lobular growth pattern was observed in the deep subcutaneous tissue. Light microscopy revealed epithelioid, ovoid, and spindle-shaped cells with a reticular cordlike pattern. Immunohistochemistry results were positive for S100, CD34, and vimentin. Break-apart fluorescence in situ hybridization assay results for ALK were also positive. These findings were consistent with those of SAMS. This case suggests that SAMS should be considered when identifying large nonspecific masses during clinical and imaging evaluation.

11.
Exp Mol Med ; 56(9): 2052-2064, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39261656

RESUMEN

The regulatory role of the inhibitor of NF-kB kinase ε (IKKε) in postmyocardial infarction (MI) inflammation remains uncertain. Using an MI mouse model, we examined the cardiac outcomes of IKKε knockout (KO) mice and wild-type mice. We employed single-cell RNA sequencing (scRNA-seq) and phosphorylated protein array techniques to profile cardiac macrophages. IKKε KO mice exhibited compromised survival, heightened inflammation, pronounced cardiac fibrosis, and a reduced ejection fraction. A distinct cardiac macrophage subset in IKKε KO mice exhibited increased fibrotic marker expression and decreased phosphorylated p38 (p-p38) levels, indicating an enhanced macrophage-myofibroblast transition (MMT) post-MI. While cardiac inflammation is crucial for initiating compensatory pathways, the timely resolution of inflammation was impaired in the IKKε KO group, while the MMT in macrophages accelerated post-MI, leading to cardiac failure. Additionally, our study highlighted the potential of 5-azacytidine (5-Aza), known for its anti-inflammatory and cardioprotective effects, in restoring p-p38 levels in stimulated macrophages. The administration of 5-Aza significantly reduced the MMT in cardiac macrophages from the IKKε KO group. These findings underscore the regulation of the inflammatory response and macrophage transition by the IKKε-p38 axis, indicating that the MMT is a promising therapeutic target for ischemic heart disease.


Asunto(s)
Modelos Animales de Enfermedad , Quinasa I-kappa B , Macrófagos , Ratones Noqueados , Infarto del Miocardio , Miofibroblastos , Animales , Masculino , Ratones , Quinasa I-kappa B/metabolismo , Quinasa I-kappa B/genética , Macrófagos/metabolismo , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Miofibroblastos/metabolismo , Miofibroblastos/patología
12.
Exp Mol Med ; 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39482535

RESUMEN

Mitochondrial dysfunction induced by mitochondrial DNA (mtDNA) mutations has been implicated in various human diseases. A comprehensive analysis of mitochondrial genetic disorders requires suitable animal models for human disease studies. While gene knockout via premature stop codons is a powerful method for investigating the unique functions of target genes, achieving knockout of mtDNA has been rare. Here, we report the genotypes and phenotypes of heteroplasmic MT-ND5 gene-knockout mice. These mutant mice presented damaged mitochondrial cristae in the cerebral cortex, hippocampal atrophy, and asymmetry, leading to learning and memory abnormalities. Moreover, mutant mice are susceptible to obesity and thermogenetic disorders. We propose that these mtDNA gene-knockdown mice could serve as valuable animal models for studying the MT-ND5 gene and developing therapies for human mitochondrial disorders in the future.

13.
J Am Chem Soc ; 135(7): 2787-92, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23350583

RESUMEN

Sodium ion batteries (SIBs) have many advantages such as the low price and abundance of sodium raw materials that are suitable for large-scale energy storage applications. Herein, we report an Mn-based pyrophosphate, Na(2)MnP(2)O(7), as a new SIB cathode material. Unlike most Mn-based cathode materials, which suffer severely from sluggish kinetics, Na(2)MnP(2)O(7) exhibits good electrochemical activity at ~3.8 V vs Na/Na(+) with a reversible capacity of 90 mAh g(-1) at room temperature. It also shows an excellent cycling and rate performance: 96% capacity retention after 30 cycles and 70% capacity retention at a c-rate increase from 0.05C to 1C. These electrochemical activities of the Mn-containing cathode material even at room temperature with relatively large particle sizes are remarkable considering an almost complete inactivity of the Li counterpart, Li(2)MnP(2)O(7). Using first-principles calculations, we find that the significantly enhanced kinetics of Na(2)MnP(2)O(7) is mainly due to the locally flexible accommodation of Jahn-Teller distortions aided by the corner-sharing crystal structure in triclinic Na(2)MnP(2)O(7). By contrast, in monoclinic Li(2)MnP(2)O(7), the edge-sharing geometry causes multiple bonds to be broken and formed during charging reaction with a large degree of atomic rearrangements. We expect that the similar computational strategy to analyze the atomic rearrangements can be used to predict the kinetics behavior when exploring new cathode candidates.

14.
J Pers Med ; 13(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36675769

RESUMEN

Postoperative skin necrosis occurs due to various causes, including infections, lack of oxygenation, underlying diseases, and lack of nutrition. Therefore, a thorough evaluation of the cause of skin necrosis should be conducted. In the present case, the patient underwent disarticulation of the interphalangeal joint of the right first toe by an orthopedic surgeon and developed postoperative skin necrosis. Through physical examination, imaging studies, and detailed medical history evaluation, the patient was diagnosed with thromboangiitis obliterans, also known as Buerger's disease. After 4 months of medication for Buerger's disease and smoking cessation, the wound healed without complications or recurrence. Therefore, in cases of untreatable chronic wounds in young and heavy smoking patients, Buerger's disease should be suspected as a potential cause.

15.
Methods Mol Biol ; 2606: 99-119, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36592311

RESUMEN

Base editors, such as cytosine and adenine base editors, are composed of nickase Cas9 (nCas9) and deaminase and serve as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based enzymatic tools for specific nucleotide substitutions. They are mainly the most effective genome editing tools for introducing point mutations, such as C-to-T and A-to-G conversions. The enhanced base editor, a C-to-G base editor (CGBE), can perform other nucleotide substitutions, such as C-to-G conversions. Here, we introduce a method for generating mouse models with point mutations using a base editing system.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Ratones , Animales , Sistemas CRISPR-Cas/genética , Edición Génica/métodos , Mutagénesis , Mutación Puntual , Nucleótidos
16.
World J Clin Cases ; 11(27): 6640-6645, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37900227

RESUMEN

BACKGROUND: Case reports of symmetric digital gangrene resulting from high-dose vasopressors use in patients with alcoholic ketoacidosis, leading to cardiac arrest, are rare. To date, no specific treatment method for autolysis or surgical amputation or guidelines for determining the level of amputation have been established. CASE SUMMARY: In this case report, we describe a treatment method that effectively preserved the function of fingers by surgical treatment under local anesthesia with a minimum operative time, while also preserving finger length to the maximum possible extent. CONCLUSION: Our approach may contribute to improved postoperative quality of life by preserving finger length.

17.
Arch Craniofac Surg ; 24(6): 288-291, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38176763

RESUMEN

This case report describes our treatment of a persistent periantral abscess in a 35-year-old woman. The abscess developed following a zygoma-reduction surgery, during which a preexisting fungal ball had not been addressed. Our comprehensive treatment approach included functional endoscopic sinus surgery, fungal ball removal, abscess drainage, and debridement. Two weeks postoperatively, the patient's symptoms had resolved. A 6-month postoperative follow-up revealed no signs of recurrence or complications, and the patient reported satisfactory functional and aesthetic results. This case underscores the importance of thorough preoperative evaluations and raises awareness about the potential risks of untreated asymptomatic pathologies, which can potentially progress and lead to further complications.

18.
ACS Nano ; 17(14): 13938-13947, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37410957

RESUMEN

The application of two-dimensional materials has been expanded by introducing the twisted bilayer (TBL) system. However, the landscape of the interlayer interaction in hetero-TBLs has not yet been fully understood, while that in homo-TBLs has been extensively studied, with the dependence on the twist angle between the constituent layers. Here, we present detailed analyses on the interlayer interaction that depends on the twist angle in WSe2/MoSe2 hetero-TBL via Raman and photoluminescence studies combined with first-principles calculation. We observe interlayer vibrational modes, moiré phonons, and the interlayer excitonic states that evolve with the twist angle and identify different regimes with distinct characteristics of such features. Moreover, the interlayer excitons that appear strong in the hetero-TBLs with twist angles near 0° or 60° have different energies and photoluminescence excitation spectra for the two cases, which results from different electronic structures and carrier relaxation dynamics. These results would enable a better understanding of the interlayer interaction in hetero-TBLs.

19.
Sci Rep ; 13(1): 6784, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37100892

RESUMEN

Perinatal outcomes of twin pregnancies are determined by several factors, such as gestational age (GA), chorionicity, and discordance at birth. This retrospective study aimed to investigate the association of chorionicity and discordance with neonatal and neurodevelopmental outcomes in preterm twin infants from uncomplicated pregnancy. Data of very preterm twin infants who were both live-born between 2014 and 2019 on the chorionicity of the twin, diagnosis of the twin-to-twin syndrome (TTTS), weight discordance at birth, and neonatal and neurodevelopmental outcomes at 24 months of corrected age (CA) were collected. Of the 204 twin infants analyzed, 136 were dichorionic (DC) and 68 were monochorionic (MC), including 15 pairs with TTTS. After adjusting for GA, brain injury, including severe intraventricular hemorrhage and periventricular leukomalacia, was mostly found in the MC with TTTS group, with a higher incidence of cerebral palsy and motor delay at CA 24 months. After excluding TTTS, multivariable analysis showed no association between chorionicity and neonatal and developmental outcomes, whereas small infants among co-twins (adjusted odds ratio (aOR) 3.33, 95% confidence interval 1.03-10.74) and greater discordance (%) of weight at birth (aOR 1.04, 1.00-1.07) were associated with neurodevelopmental impairment. Monochorionicity might not determine adverse outcomes among very preterm twins from uncomplicated pregnancy.


Asunto(s)
Recien Nacido Extremadamente Prematuro , Gemelos , Embarazo , Recién Nacido , Lactante , Femenino , Humanos , Estudios Retrospectivos , Embarazo Gemelar , Edad Gestacional , Retardo del Crecimiento Fetal/epidemiología , Resultado del Embarazo , Gemelos Monocigóticos
20.
Exp Mol Med ; 55(12): 2586-2595, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38036737

RESUMEN

Base editors are powerful tools for making precise single-nucleotide changes in the genome. However, they can lead to unintended insertions and deletions at the target sites, which is a significant limitation for clinical applications. In this study, we aimed to eliminate unwanted indels at the target sites caused by various evolved base editors. Accordingly, we applied dead Cas9 instead of nickase Cas9 in the base editors to induce accurate substitutions without indels. Additionally, we tested the use of chromatin-modulating peptides in the base editors to improve nucleotide conversion efficiency. We found that using both dead Cas9 and chromatin-modulating peptides in base editing improved the nucleotide substitution efficiency without unintended indel mutations at the desired target sites in human cell lines and mouse primary myoblasts. Furthermore, the proposed scheme had fewer off-target effects than conventional base editors at the DNA level. These results indicate that the suggested approach is promising for the development of more accurate and safer base editing techniques for use in clinical applications.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Humanos , Ratones , Animales , Edición Génica/métodos , Mutación INDEL , Cromatina , Nucleótidos , Péptidos
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