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1.
Mol Biol Evol ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842255

RESUMEN

The origins and extreme morphological evolution of the modern dog breeds are poorly studied because the founder populations are extinct. Here, we analyse eight 100-200 years old dog fur samples obtained from traditional North Swedish clothing, to explore the origin and artificial selection of the modern Nordic Lapphund and Elkhound dog breeds. Population genomic analysis confirmed the Lapphund and Elkhound breeds to originate from the local dog population, and showed a distinct decrease in genetic diversity in agreement with intense breeding. We identified eleven genes under positive selection during the breed development. In particular, the MSRB3 gene, associated with breed-related ear morphology, was selected in all Lapphund and Elkhound breeds, and functional assays showed that a SNP mutation in the 3'UTR region suppresses its expression through miRNA regulation. Our findings demonstrate analysis of near-modern dog artifacts as an effective tool for interpreting the origin and artificial selection of the modern dog breeds.

2.
Nat Commun ; 15(1): 4643, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38821959

RESUMEN

Silk nanofibrils (SNFs), the fundamental building blocks of silk fibers, endow them with exceptional properties. However, the intricate mechanism governing SNF assembly, a process involving both protein conformational transitions and protein molecule conjunctions, remains elusive. This lack of understanding has hindered the development of artificial silk spinning techniques. In this study, we address this challenge by employing a graphene plasmonic infrared sensor in conjunction with multi-scale molecular dynamics (MD). This unique approach allows us to probe the secondary structure of nanoscale assembly intermediates (0.8-6.2 nm) and their morphological evolution. It also provides insights into the dynamics of silk fibroin (SF) over extended molecular timeframes. Our novel findings reveal that amorphous SFs undergo a conformational transition towards ß-sheet-rich oligomers on graphene. These oligomers then connect to evolve into SNFs. These insights provide a comprehensive picture of SNF assembly, paving the way for advancements in biomimetic silk spinning.

3.
Nat Commun ; 15(1): 4463, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796473

RESUMEN

Polaritons are well-established carriers of light, electrical signals, and even heat at the nanoscale in the setting of on-chip devices. However, the goal of achieving practical polaritonic manipulation over small distances deeply below the light diffraction limit remains elusive. Here, we implement nanoscale polaritonic in-plane steering and cloaking in a low-loss atomically layered van der Waals (vdW) insulator, α-MoO3, comprising building blocks of customizable stacked and assembled structures. Each block contributes specific characteristics that allow us to steer polaritons along the desired trajectories. Our results introduce a natural materials-based approach for the comprehensive manipulation of nanoscale optical fields, advancing research in the vdW polaritonics domain and on-chip nanophotonic circuits.

4.
STAR Protoc ; 5(2): 103039, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38669138

RESUMEN

In this protocol, we present a facile nanoscale thermal mapping technique for electronic devices by use of atomic force microscopy and a phase change material Ge2Sb2Te5. We describe steps for Ge2Sb2Te5 thin film coating, Ge2Sb2Te5 temperature calibration, thermal mapping by varying heater power, and thermal mapping by varying heating time. The protocol can be applied for resolving surface temperatures of various operational microelectronic devices with a nanoscale precision. For complete details on the use and execution of this protocol, please refer to Cheng et al.1.

6.
Magn Reson Med ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38650444

RESUMEN

PURPOSE: To improve image quality, mitigate quantification biases and variations for free-breathing liver proton density fat fraction (PDFF) and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ quantification accelerated by radial k-space undersampling. METHODS: A free-breathing multi-echo stack-of-radial MRI method was developed with compressed sensing with multidimensional regularization. It was validated in motion phantoms with reference acquisitions without motion and in 11 subjects (6 patients with nonalcoholic fatty liver disease) with reference breath-hold Cartesian acquisitions. Images, PDFF, and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ maps were reconstructed using different radial view k-space sampling factors and reconstruction settings. Results were compared with reference-standard results using Bland-Altman analysis. Using linear mixed-effects model fitting (p < 0.05 considered significant), mean and SD were evaluated for biases and variations of PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ , respectively, and coefficient of variation on the first echo image was evaluated as a surrogate for image quality. RESULTS: Using the empirically determined optimal sampling factor of 0.25 in the accelerated in vivo protocols, mean differences and limits of agreement for the proposed method were [-0.5; -33.6, 32.7] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-1.0%; -5.8%, 3.8%] for PDFF, close to those of a previous self-gating method using fully sampled radial views: [-0.1; -27.1, 27.0] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-0.4%; -4.5%, 3.7%] for PDFF. The proposed method had significantly lower coefficient of variation than other methods (p < 0.001). Effective acquisition time of 64 s or 59 s was achieved, compared with 171 s or 153 s for two baseline protocols with different radial views corresponding to sampling factor of 1.0. CONCLUSION: This proposed method may allow accelerated free-breathing liver PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ mapping with reduced biases and variations.

7.
Am J Case Rep ; 25: e943134, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38494665

RESUMEN

BACKGROUND Chemical burns in the oral cavity, although rare, cause more severe tissue damage than thermal burns, continuing tissue destruction even after removing the causative substance. Prompt identification of the substance, exposure extent, time from injury to treatment, and the injured area are imperative for effective management. This report details severe oral burns in an elderly woman from accidental NaOH ingestion. CASE REPORT A 70-year-old female patient was presented to our hospital approximately 15 h after inadvertent consumption of approximately 20 ml of NaOH (sodium hydroxide) solution. This incident led to oral discomfort and restricted mouth opening. The ingested solution, erroneously assumed to be a beverage, was later identified as a potent alkaline substance typically employed in grease removal. Initial manifestations included intense burning sensation, oral edema, and heightened salivation, which exacerbated on the following day, adversely impacting her alimentation and verbal communication. Clinical examination disclosed extensive damage to the oral mucosa. The diagnosis encompassed a chemical burn in the oral cavity coupled with chronic gastritis. The treatment regimen comprised dietary limitations, administration of famotidine for gastric acid suppression, intravenous hydration, nutritional support, oral care with Kangfuxin liquid, and nebulization therapy. Six months after therapy, she exhibited complete recovery, with the absence of discomfort and restored normal oral functions. CONCLUSIONS Timely and targeted treatment strategies, particularly nebulization medication and Kangfuxin liquid, are effective in managing chemical burns in the oral cavity, promoting wound healing, and preventing complications.


Asunto(s)
Quemaduras Químicas , Femenino , Humanos , Anciano , Quemaduras Químicas/etiología , Quemaduras Químicas/terapia , Hidróxido de Sodio , Boca , Cicatrización de Heridas , Ingestión de Alimentos
9.
Sci Rep ; 14(1): 5093, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429326

RESUMEN

With the continuous construction of urban traffic roads, more and more new roads are cut off by existing roads to form "dead end roads". There is an urgent need for a trenchless method suitable for urban ultra-shallow overburden to build the undercrossing tunnel. To solve this problem, this paper proposed the micro pipe jacking and joint assembly structure (MPJ & JAS) method, which has the characteristics of shallow burial depth, low cost, short construction time, flexible cross-section setting and high space utilization. The MPJ & JAS method construct a large cross-section tunnel through assembling small cross-section elements, quite different from traditional methods. Therefore, this paper designed a CT-shaped integrated joint, the mechanical performance of which was verified and clarified by tensile test. The bending test and finite element (FE) analysis proved the reliability of MPJ & JAS tunnel structure, and confirmed the structure performances such as the failure models, crack behaviors, load-deflection response and stress-strain distribution. Moreover, the influences of the steel plate thickness, concrete strength and shear connector spacing were determined by the FE analysis. On the basis of test results and reasonable assumptions, a theoretical design method considering the influence of the CT-shaped integrated joint was proposed, which can effectively predict the bending strength of the MPJ & JAS tunnel structure with an error of less than 10%. Finally, in view of the characteristics of the MPJ & JAS method, the suitable micro pipe jacking machine, soil reinforcement measure, hydraulic traction construction technology, high-precision guidance system and concrete construction quality detection method based on the phased array ultrasonic imaging technology were developed, supporting the accurate and efficient construction of the MPJ & JAS tunnel.

10.
Int J Cardiovasc Imaging ; 40(4): 863-871, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430425

RESUMEN

Growth differentiation factor-15 (GDF-15) is an anti-inflammatory cytokine with cardioprotective effects, but circulating GDF-15 concentration predicts adverse cardiovascular outcomes in clinical settings. Microvascular obstruction (MVO) formation contributed to poor prognosis in patients with ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (pPCI). We aimed to investigate GDF-15 concentration in relation to cardiac magnetic resonance (CMR)-derived MVO in STEMI patients after pPCI, which might help better understand the role of GDF-15 in STEMI. GDF-15 levels at 6 h after pPCI and MVO extent at day 5 ± 2 after pPCI were measured in 74 STEMI patients (mean age 60.3 ± 12.8 years, 86.5% men). The adjusted association of GDF-15 with MVO was analyzed with MVO treated as a categorized variable (extensive MVO, defined as MVO extent ≥ 2.6% of left ventricular (LV)) and a continuous variable (MVO mass, % of LV), respectively, in multivariate logistic and linear regression models. 41.9% of the patients developed extensive MVO after pPCI. In multivariate analysis, the odds ratio (95% confidential interval (CI)) of each standard deviation (SD) increase in GDF-15 for developing extensive MVO was 0.46 (0.21, 0.82), p = 0.02). Consistently, when MVO was used a continuous variable, each SD increase in GDF-15 was associated with a substantially lower MVO mass (ß - 0.42, standard error 0.19, p = 0.03). GDF-15 was a negative predictor for MVO in STEMI patients after pPCI. The observation was consistent with results from experiment studies, suggesting a potential protective effect of GDF-15 against cardiac injury.


Asunto(s)
Biomarcadores , Circulación Coronaria , Factor 15 de Diferenciación de Crecimiento , Microcirculación , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Infarto del Miocardio con Elevación del ST , Humanos , Factor 15 de Diferenciación de Crecimiento/sangre , Masculino , Infarto del Miocardio con Elevación del ST/sangre , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Femenino , Intervención Coronaria Percutánea/efectos adversos , Persona de Mediana Edad , Anciano , Biomarcadores/sangre , Factores de Riesgo , Resultado del Tratamiento , Factores de Tiempo , Modelos Logísticos , Modelos Lineales , Análisis Multivariante , Oportunidad Relativa , Distribución de Chi-Cuadrado , Estudios Prospectivos , Imagen por Resonancia Cinemagnética , Vasos Coronarios/diagnóstico por imagen
11.
RNA ; 30(5): 548-559, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38531647

RESUMEN

N 1-methyl adenosine (m1A) is a widespread RNA modification present in tRNA, rRNA, and mRNA. m1A modification sites in tRNAs are evolutionarily conserved and its formation on tRNA is catalyzed by methyltransferase TRMT61A and TRMT6 complex. m1A promotes translation initiation and elongation. Due to its positive charge under physiological conditions, m1A can notably modulate RNA structure. It also blocks Watson-Crick-Franklin base-pairing and causes mutation and truncation during reverse transcription. Several misincorporation-based high-throughput sequencing methods have been developed to sequence m1A. In this study, we introduce a reduction-based m1A sequencing (red-m1A-seq). We report that NaBH4 reduction of m1A can improve the mutation and readthrough rates using commercially available RT enzymes to give a better positive signature, while alkaline-catalyzed Dimroth rearrangement can efficiently convert m1A to m6A to provide good controls, allowing the detection of m1A with higher sensitivity and accuracy. We applied red-m1A-seq to sequence human small RNA, and we not only detected all the previously reported tRNA m1A sites, but also new m1A sites in mt-tRNAAsn-GTT and 5.8S rRNA.


Asunto(s)
ARN de Transferencia , ARN , Humanos , Metilación , ARN de Transferencia/química , ARN/genética , ARNt Metiltransferasas/genética , ARNt Metiltransferasas/metabolismo , Metiltransferasas/metabolismo , ARN Mensajero/genética
13.
RNA ; 30(6): 739-747, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38471794

RESUMEN

N1-methyladenosine (m1A) is a widespread modification in all eukaryotic, many archaeal, and some bacterial tRNAs. m1A is generally located in the T loop of cytosolic tRNA and between the acceptor and D stems of mitochondrial tRNAs; it is involved in the tertiary interaction that stabilizes tRNA. Human tRNA m1A levels are dynamically regulated that fine-tune translation and can also serve as biomarkers for infectious disease. Although many methods have been used to measure m1A, a PCR method to assess m1A levels quantitatively in specific tRNAs has been lacking. Here we develop a templated-ligation followed by a qPCR method (TL-qPCR) that measures m1A levels in target tRNAs. Our method uses the SplintR ligase that efficiently ligates two tRNA complementary DNA oligonucleotides using tRNA as the template, followed by qPCR using the ligation product as the template. m1A interferes with the ligation in specific ways, allowing for the quantitative assessment of m1A levels using subnanogram amounts of total RNA. We identify the features of specificity and quantitation for m1A-modified model RNAs and apply these to total RNA samples from human cells. Our method enables easy access to study the dynamics and function of this pervasive tRNA modification.


Asunto(s)
Adenosina , ARN de Transferencia , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/genética , Conformación de Ácido Nucleico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
14.
Nat Commun ; 15(1): 1888, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424092

RESUMEN

Stacking order plays a crucial role in determining the crystal symmetry and has significant impacts on electronic, optical, magnetic, and topological properties. Electron-phonon coupling, which is central to a wide range of intriguing quantum phenomena, is expected to be intricately connected with stacking order. Understanding the stacking order-dependent electron-phonon coupling is essential for understanding peculiar physical phenomena associated with electron-phonon coupling, such as superconductivity and charge density waves. In this study, we investigate the effect of stacking order on electron-infrared phonon coupling in graphene trilayers. By using gate-tunable Raman spectroscopy and excitation frequency-dependent near-field infrared nanoscopy, we show that rhombohedral ABC-stacked trilayer graphene has a significant electron-infrared phonon coupling strength. Our findings provide novel insights into the superconductivity and other fundamental physical properties of rhombohedral ABC-stacked trilayer graphene, and can enable nondestructive and high-throughput imaging of trilayer graphene stacking order using Raman scattering.

15.
Nanoscale ; 16(8): 4148-4156, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38348698

RESUMEN

The escalating interest in low-dimensional perovskites stems from their tunable optoelectronic traits and robust stability. The pursuit of multifaceted optoelectronic devices holds substantial importance for energy-efficient and space-constrained systems. This investigation showcases the realization of multifunctional two-dimensional perovskite solar cells, incorporating transient light detection and resistive switching functions within a single device, achievable by facile external bias adjustments. Serving as a photodetector, the device exhibits commendable self-powered photodetection attributes, including an exceptionally low dark current density of 1 nA mm-2, a remarkable specific detectivity of 7.67 × 1012 Jones, a swift response time of 0.60 µs, and an expansive linear dynamic range of 72 dB. As a memristor, it showcases enduring performance across 4 × 102 cycles, a substantial on/off ratio of 106, and a rapid operation time of less than 1 µs. This endeavor unveils a pioneering avenue for advancing high-performance, air-stable multifunctional two-dimensional perovskite electronics.

17.
J Glob Antimicrob Resist ; 36: 252-259, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38272210

RESUMEN

OBJECTIVES: To investigate the factors influencing imipenem/cilastatin (IMI) and meropenem (MEM) concentrations in critically ill adult patients and the role of these concentrations in the clinical outcome. METHODS: Plasma trough concentrations of IMI and MEM were detected by high-performance liquid chromatography. A target value of 100%-time above MIC was used for the drugs. RESULTS: A total of 186 patients were included, with 87 receiving IMI and 99 receiving MEM. The percentages of patients reaching the target IMI and MEM concentrations were 44.8% and 38.4%, respectively. The proportions of patients infected with drug-resistant bacteria were 57.5% and 69.7% in the IMI group and MEM group, respectively. In the multivariate analysis, the risk factors for an IMI concentration that did not reach the target were infection with drug-resistant bacteria, and those for MEM were infection with drug-resistant bacteria, estimated glomerular filtration rate, and diabetes mellitus. A total of 47.1% of patients had good outcomes in the IMI cohort, and 38.1% of patients had good outcomes in the MEM cohort. The duration of mechanical ventilation and IMI concentration were associated with ICU stay in patients in the IMI cohort, while MEM concentration and severe pneumonia affected the clinical outcome of patients in the MEM cohort. CONCLUSION: Infection with drug-resistant bacteria is an important factor influencing whether IMI and MEM concentrations reach the target. Furthermore, IMI and MEM concentrations are associated with the clinical outcome, and elevated doses of IMI and MEM should be given to patients who are infected with drug-resistant bacteria.


Asunto(s)
Cilastatina , Imipenem , Adulto , Humanos , Meropenem/uso terapéutico , Imipenem/uso terapéutico , Cilastatina/uso terapéutico , Enfermedad Crítica , Monitoreo de Drogas , Combinación de Medicamentos , Combinación Cilastatina e Imipenem
19.
Nat Mater ; 23(4): 506-511, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38191633

RESUMEN

Surface plasmon polaritons and phonon polaritons offer a means of surpassing the diffraction limit of conventional optics and facilitate efficient energy storage, local field enhancement and highsensitivity sensing, benefiting from their subwavelength confinement of light. Unfortunately, losses severely limit the propagation decay length, thus restricting the practical use of polaritons. While optimizing the fabrication technique can help circumvent the scattering loss of imperfect structures, the intrinsic absorption channel leading to heat production cannot be eliminated. Here, we utilize synthetic optical excitation of complex frequency with virtual gain, synthesized by combining the measurements made at multiple real frequencies, to compensate losses in the propagations of phonon polaritons with dramatically enhanced propagation distance. The concept of synthetic complex frequency excitation represents a viable solution to the loss problem for various applications including photonic circuits, waveguiding and plasmonic/phononic structured illumination microscopy.

20.
Nat Biotechnol ; 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38168991

RESUMEN

Bisulfite sequencing (BS-seq) to detect 5-methylcytosine (5mC) is limited by lengthy reaction times, severe DNA damage, overestimation of 5mC level and incomplete C-to-U conversion of certain DNA sequences. We present ultrafast BS-seq (UBS-seq), which uses highly concentrated bisulfite reagents and high reaction temperatures to accelerate the bisulfite reaction by ~13-fold, resulting in reduced DNA damage and lower background noise. UBS-seq allows library construction from small amounts of purified genomic DNA, such as from cell-free DNA or directly from 1 to 100 mouse embryonic stem cells, with less overestimation of 5mC level and higher genome coverage than conventional BS-seq. Additionally, UBS-seq quantitatively maps RNA 5-methylcytosine (m5C) from low inputs of mRNA and allows the detection of m5C stoichiometry in highly structured RNA sequences. Our UBS-seq results identify NSUN2 as the major 'writer' protein responsible for the deposition of ~90% of m5C sites in HeLa mRNA and reveal enriched m5C sites in 5'-regions of mammalian mRNA, which may have functional roles in mRNA translation regulation.

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