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1.
PLoS Biol ; 22(7): e3002646, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39012916

RESUMEN

Autism spectrum disorders (ASDs) are considered neural dysconnectivity syndromes. To better understand ASD and uncover potential treatments, it is imperative to know and dissect the connectivity deficits under conditions of autism. Here, we apply a whole-brain immunostaining and quantification platform to demonstrate impaired structural and functional connectivity and aberrant whole-brain synchronization in a Tbr1+/- autism mouse model. We express a channelrhodopsin variant oChIEF fused with Citrine at the basolateral amygdala (BLA) to outline the axonal projections of BLA neurons. By activating the BLA under blue light theta-burst stimulation (TBS), we then evaluate the effect of BLA activation on C-FOS expression at a whole brain level to represent neural activity. We show that Tbr1 haploinsufficiency almost completely disrupts contralateral BLA axonal projections and results in mistargeting in both ipsilateral and contralateral hemispheres, thereby globally altering BLA functional connectivity. Based on correlated C-FOS expression among brain regions, we further show that Tbr1 deficiency severely disrupts whole-brain synchronization in the absence of salient stimulation. Tbr1+/- and wild-type (WT) mice exhibit opposing responses to TBS-induced amygdalar activation, reducing synchronization in WT mice but enhancing it in Tbr1+/- mice. Whole-brain modular organization and intermodule connectivity are also affected by Tbr1 deficiency and amygdalar activation. Following BLA activation by TBS, the synchronizations of the whole brain and the default mode network, a specific subnetwork highly relevant to ASD, are enhanced in Tbr1+/- mice, implying a potential ameliorating effect of amygdalar stimulation on brain function. Indeed, TBS-mediated BLA activation increases nose-to-nose social interactions of Tbr1+/- mice, strengthening evidence for the role of amygdalar connectivity in social behaviors. Our high-resolution analytical platform reveals the inter- and intrahemispheric connectopathies arising from ASD. Our study emphasizes the defective synchronization at a whole-brain scale caused by Tbr1 deficiency and implies a potential beneficial effect of deep brain stimulation at the amygdala for TBR1-linked autism.


Asunto(s)
Trastorno del Espectro Autista , Complejo Nuclear Basolateral , Estimulación Encefálica Profunda , Modelos Animales de Enfermedad , Conducta Social , Proteínas de Dominio T Box , Animales , Trastorno del Espectro Autista/fisiopatología , Trastorno del Espectro Autista/metabolismo , Trastorno del Espectro Autista/genética , Proteínas de Dominio T Box/metabolismo , Proteínas de Dominio T Box/genética , Complejo Nuclear Basolateral/metabolismo , Complejo Nuclear Basolateral/fisiopatología , Ratones , Estimulación Encefálica Profunda/métodos , Masculino , Amígdala del Cerebelo/metabolismo , Amígdala del Cerebelo/fisiopatología , Encéfalo/metabolismo , Encéfalo/fisiopatología , Ratones Endogámicos C57BL , Vías Nerviosas/fisiopatología , Vías Nerviosas/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo
2.
Nucleic Acids Res ; 52(12): 7158-7170, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38842939

RESUMEN

Prolyl-tRNA synthetases (ProRSs) are unique among aminoacyl-tRNA synthetases (aaRSs) in having two distinct structural architectures across different organisms: prokaryote-like (P-type) and eukaryote/archaeon-like (E-type). Interestingly, Bacillus thuringiensis harbors both types, with P-type (BtProRS1) and E-type ProRS (BtProRS2) coexisting. Despite their differences, both enzymes are constitutively expressed and functional in vivo. Similar to BtProRS1, BtProRS2 selectively charges the P-type tRNAPro and displays higher halofuginone tolerance than canonical E-type ProRS. However, these two isozymes recognize the primary identity elements of the P-type tRNAPro-G72 and A73 in the acceptor stem-through distinct mechanisms. Moreover, BtProRS2 exhibits significantly higher tolerance to stresses (such as heat, hydrogen peroxide, and dithiothreitol) than BtProRS1 does. This study underscores how an E-type ProRS adapts to a P-type tRNAPro and how it may contribute to the bacterium's survival under stress conditions.


Asunto(s)
Aminoacil-ARNt Sintetasas , Bacillus thuringiensis , Aminoacil-ARNt Sintetasas/metabolismo , Aminoacil-ARNt Sintetasas/genética , Bacillus thuringiensis/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Células Procariotas/metabolismo , Estrés Fisiológico
3.
Nano Lett ; 24(37): 11482-11489, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39158148

RESUMEN

A novel antiferroelectric material, PbSnO3 (PSO), was introduced into a resistive random access memory (RRAM) to reveal its resistive switching (RS) properties. It exhibits outstanding electrical performance with a large memory window (>104), narrow switching voltage distribution (±2 V), and low power consumption. Using high-resolution transmission electron microscopy, we observed the antiferroelectric properties and remanent polarization of the PSO thin films. The in-plane shear strains in the monoclinic PSO layer are attributed to oxygen octahedral tilts, resulting in misfit dislocations and grain boundaries at the PSO/SRO interface. Furthermore, the incoherent grain boundaries between the orthorhombic and monoclinic phases are assumed to be the primary paths of Ag+ filaments. Therefore, the RS behavior is primarily dominated by antiferroelectric polarization and defect mechanisms for the PSO structures. The RS behavior of antiferroelectric heterostructures controlled by switching spontaneous polarization and strain, defects, and surface chemistry reactions can facilitate the development of new antiferroelectric device systems.

4.
J Biol Chem ; 299(9): 105149, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37567477

RESUMEN

Alanyl-tRNA synthetase retains a conserved prototype structure throughout its biology. Nevertheless, its C-terminal domain (C-Ala) is highly diverged and has been shown to play a role in either tRNA or DNA binding. Interestingly, we discovered that Caenorhabditis elegans cytoplasmic C-Ala (Ce-C-Alac) robustly binds both ligands. How Ce-C-Alac targets its cognate tRNA and whether a similar feature is conserved in its mitochondrial counterpart remain elusive. We show that the N- and C-terminal subdomains of Ce-C-Alac are responsible for DNA and tRNA binding, respectively. Ce-C-Alac specifically recognized the conserved invariant base G18 in the D-loop of tRNAAla through a highly conserved lysine residue, K934. Despite bearing little resemblance to other C-Ala domains, C. elegans mitochondrial C-Ala robustly bound both tRNAAla and DNA and maintained targeting specificity for the D-loop of its cognate tRNA. This study uncovers the underlying mechanism of how C. elegans C-Ala specifically targets the D-loop of tRNAAla.


Asunto(s)
Alanina-ARNt Ligasa , Caenorhabditis elegans , Motivos de Nucleótidos , ARN de Transferencia de Alanina , Animales , Alanina-ARNt Ligasa/química , Alanina-ARNt Ligasa/metabolismo , Caenorhabditis elegans/enzimología , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Secuencia Conservada , Citoplasma/enzimología , ADN/química , ADN/metabolismo , Ligandos , Lisina/metabolismo , Mitocondrias/enzimología , Dominios Proteicos , ARN de Transferencia de Alanina/química , ARN de Transferencia de Alanina/metabolismo , Especificidad por Sustrato , Conformación de Ácido Nucleico
5.
J Gene Med ; 26(1): e3616, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38049938

RESUMEN

BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a rare tumor with extraordinarily different features between Eastern and Western countries. Vascular endothelial growth factor-A (VEGFA) was originally identified as a secreted signaling protein and regulator of vascular development and cancer progression. In this study, we aimed to elucidate the molecular mechanisms underlying the regulation of VEGFA by microRNA in UTUC. METHODS: VEGFA expression was evaluated by immunohistochemistry in 140 human UTUC tissue samples. Next, we assessed the regulatory relationship between VEGFA and miR-299-3p by real-time PCR, western blotting, ELISA and dual-luciferase reporter assays using two UTUC cell lines. The role of miR-299-3p/VEGFA in cell proliferation, motility, invasion, and tube formation was analyzed in vitro. RESULTS: High VEGFA expression was significantly associated with tumor stage, grade, distant metastasis and cancer-related death and correlated with poor progression-free and cancer-specific survival. VEGFA knockdown repressed proliferation, migration, invasion and angiogenesis in UTUC cell lines. miR-299-3p significantly reduced VEGFA protein expression and miR-299-3p overexpression inhibited VEGFA mRNA and protein expression by directly targeting its 3'-UTR. Functional studies indicated that VEGFA overexpression reversed the miR-299-3p-mediated suppression of tumor cell proliferation, migration, invasion and angiogenesis. In addition, miR-299-3p/VEGFA suppressed cellular functions in UTUC by modulating the expression of P18 and cyclin E2. CONCLUSIONS: Our findings suggest that miR-299-3p possibly suppresses UTUC cell proliferation, motility, invasion and angiogenesis via VEGFA. VEGFA may act as a prognostic predictor, and both VEGFA and miR-299-3p could be potential therapeutic targets for UTUC.


Asunto(s)
Carcinoma de Células Transicionales , MicroARNs , Neoplasias de la Vejiga Urinaria , Humanos , Angiogénesis , Carcinoma de Células Transicionales/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias de la Vejiga Urinaria/genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
6.
Small ; : e2404782, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162100

RESUMEN

2D nanomaterials with ångström-scale thicknesses offer a unique platform for confining molecules at an unprecedentedly small scale, presenting novel opportunities for modulating material properties and probing microscopic phenomena. In this study, mesogen-tethered polyhedral oligomeric silsesquioxane (POSS) amphiphiles with varying numbers of mesogenic tails to systematically influence molecular self-assembly and the architecture of the ensuing supramolecular structures, are synthesized. These organic-inorganic hybrid amphiphiles facilitate precise spatial arrangement and directional alignment of the primary molecular units within highly ordered supramolecular structures. The correlation between molecular design and the formation of superlattices through comprehensive structural analyses, incorporating molecular thermodynamics and kinetics, is explored. The distinct intermolecular interactions of the POSS core and the mesogenic tails drive the preferential formation of a 2D inorganic sublattice while simultaneously guiding the hierarchical assembly of organic lamellae via soft epitaxy. The findings reveal the intricate balance between shape, size, and interaction strengths of the inorganic and organic components, and how these factors collectively influence the structural hierarchy of the superstructures, which consist of multiple sublattices. By controlling this unique molecular behavior, it is possible to modulate or maximize the anisotropy of optical, mechanical, and electrical properties at the sub-nanometer scale for nanotechnology applications.

7.
Respir Res ; 25(1): 139, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521900

RESUMEN

BACKGROUND: DEHP, a common plasticizer known for its hormone-disrupting properties, has been associated with asthma. However, a significant proportion of adult asthma cases are "non-atopic", lacking a clear etiology. METHODS: In a case-control study conducted between 2011 and 2015, 365 individuals with current asthma and 235 healthy controls from Kaohsiung City were enrolled. The control group comprised individuals without asthma, Type 2 Diabetes Mellitus (T2DM), hypertension, or other respiratory/allergic conditions. The study leveraged asthma clusters (Clusters A to F) established in a prior investigation. Analysis involved the examination of urinary DEHP metabolites (MEHP and MEHHP), along with the assessment of oxidative stress, sphingolipid metabolites, and inflammatory biomarkers. Statistical analyses encompassed Spearman's rank correlation coefficients, multiple logistic regression, and multinomial logistic regression. RESULTS: Asthma clusters (E, D, C, F, A) exhibited significantly higher ORs of MEHHP exposures compared to the control group. When considering asthma-related comorbidities (T2DM, hypertension, or both), patients without comorbidities demonstrated significantly higher ORs of the sum of primary and secondary metabolites (MEHP + MEHHP) and MEHHP compared to those with asthma comorbidities. A consistent positive correlation between urinary HEL and DEHP metabolites was observed, but a consistent negative correlation between DEHP metabolites and selected cytokines was identified. CONCLUSION: The current study reveals a heightened risk of MEHHP and MEHP + MEHHP exposure in specific asthma subgroups, emphasizing its complex relationship with asthma. The observed negative correlation with cytokines suggests a new avenue for research, warranting robust evidence from epidemiological and animal studies.


Asunto(s)
Asma , Diabetes Mellitus Tipo 2 , Dietilhexil Ftalato , Dietilhexil Ftalato/análogos & derivados , Hipertensión , Ácidos Ftálicos , Adulto , Animales , Humanos , Dietilhexil Ftalato/toxicidad , Dietilhexil Ftalato/orina , Exposición a Riesgos Ambientales , Estudios de Casos y Controles , Asma/inducido químicamente , Asma/diagnóstico , Asma/epidemiología , Citocinas
8.
Phys Rev Lett ; 132(6): 067001, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38394602

RESUMEN

Electrically driven spin resonance is a powerful technique for controlling semiconductor spin qubits. However, it faces challenges in qubit addressability and off-resonance driving in larger systems. We demonstrate coherent bichromatic Rabi control of quantum dot hole spin qubits, offering a spatially selective approach for large qubit arrays. By applying simultaneous microwave bursts to different gate electrodes, we observe multichromatic resonance lines and resonance anticrossings that are caused by the ac Stark shift. Our theoretical framework aligns with experimental data, highlighting interdot motion as the dominant mechanism for bichromatic driving.

9.
Neuroendocrinology ; 114(10): 921-933, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38885623

RESUMEN

INTRODUCTION: Cancer stem cells (CSCs) shape the tumor microenvironment via neuroendocrine signaling and orchestrate drug resistance and metastasis. Cytokine antibody array demonstrated the upregulation of neurotrophin-3 (NT-3) in lung CSCs. This study aims to dissect the role of NT-3 in lung CSCs during tumor innervation. METHODS: Western blotting, quantitative reverse transcription-PCR, and flow cytometry were used to determine the expression of the NT-3 axis in lung CSCs. NT-3-knockdown and NT-3-overexpressed cells were derived lung CSCs, followed by examining the stemness gene expression, tumorsphere formation, transwell migration and invasion, drug resistance, soft agar colony formation, and in vivo tumorigenicity. Human lung cancer tissue microarray and bioinformatic databases were used to investigate the clinical relevance of NT-3 in lung cancer. RESULTS: NT-3 and its receptor tropomyosin receptor kinase C (TrkC) were augmented in lung tumorspheres. NT-3 silencing (shNT-3) suppressed the migration and anchorage-independent growth of lung cancer cells. Further, shNT-3 abolished the sphere-forming capability, chemo-drug resistance, invasion, and in vivo tumorigenicity of lung tumorspheres with a decreased expression of CSC markers. Conversely, NT-3 overexpression promoted migration and anchorage-independent growth and fueled tumorsphere formation by upregulating the expression of CSC markers. Lung cancer tissue microarray analysis revealed that NT-3 increased in patients with advanced-stage, lymphatic metastasis and positively correlated with Sox2 expression. Bioinformatic databases confirmed a co-expression of NT-3/TrkC-axis and demonstrated that NT-3, NT-3/TrkC, NT-3/Sox2, and NT-3/CD133 worsen the survival of lung cancer patients. CONCLUSION: NT-3 conferred the stemness features in lung cancer during tumor innervation, which suggests that NT-3-targeting is feasible in eradicating lung CSCs.


Asunto(s)
Neoplasias Pulmonares , Células Madre Neoplásicas , Neurotrofina 3 , Humanos , Neurotrofina 3/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Animales , Línea Celular Tumoral , Ratones , Receptor trkC/metabolismo , Receptor trkC/genética , Movimiento Celular/fisiología , Regulación Neoplásica de la Expresión Génica
10.
Value Health ; 27(2): 153-163, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38042333

RESUMEN

OBJECTIVES: To assess the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine as second-line therapy for patients with human epidermal growth factor receptor 2 positive metastatic breast cancer from a US healthcare sector perspective. METHODS: A 3-state partitioned survival model was developed to estimate the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine. For both treatments, modeled patients were administered treatment intravenously every 3 weeks indefinitely or until disease progression. Transition parameters were principally derived from the updated DESTINY-Breast03 phase III randomized clinical trial. Costs include drug costs extracted from Centers for Medicare and Medicaid Services average sales price and administrative, adverse event, and third-line therapy costs derived from published literature, measured in 2022 US dollars. Health utilities for health states and disutilities for adverse events were sourced from published literature. Effects were measured in quality-adjusted life years (QALYs). We conducted both probabilistic sensitivity analysis and comprehensive scenario analysis to test model assumptions and robustness, while utilizing a lifetime horizon. RESULTS: In our base-case analysis, total costs for trastuzumab deruxtecan were $1 266 945, compared with $820 082 for trastuzumab emtansine. Total QALYs for trastuzumab deruxtecan were 5.09, compared with 3.15 for trastuzumab emtansine. The base-case incremental cost-effectiveness ratio was $230 285/QALY. Probabilistic sensitivity analysis indicated that trastuzumab deruxtecan had an 11.1% probability of being cost-effective at a $100 000 per QALY willingness-to-pay threshold. CONCLUSIONS: Despite the higher efficacy of trastuzumab deruxtecan in patients with human epidermal growth factor receptor 2 positive metastatic breast cancer, our findings raise concern regarding its value at current prices.


Asunto(s)
Neoplasias de la Mama , Camptotecina/análogos & derivados , Inmunoconjugados , Anciano , Humanos , Estados Unidos , Femenino , Ado-Trastuzumab Emtansina/uso terapéutico , Análisis de Costo-Efectividad , Análisis Costo-Beneficio , Medicare , Trastuzumab , Receptor ErbB-2/metabolismo , Años de Vida Ajustados por Calidad de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
11.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): 1019-1026, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856409

RESUMEN

We present a highly efficient method for characterizing the scattering field distribution of surface plasmon polaritons in metallic components by combining the eXtended Pseudospectral Frequency-Domain (X-PSFD) method with an iterative, machine-learning-inspired procedure. Shifting away from traditional matrix operations, we utilize the "Adam" optimizer-an effective and swift machine learning algorithm-to solve the scattering field distribution. Our method encompasses the derivation of the associated cost function and gradient differentiation of the field, leveraging spectral accuracy at Legendre collocation points in the Helmholtz equation. We refine the total-field/scattered-field (TF/SF) formulation within the X-PSFD framework for optimized incident field management and employ Chebyshev-Lagrange interpolation polynomials for rapid, accurate computation of broad-band results. To ensure global accuracy, we introduce unique physical boundary conditions at subdomain interfaces. Demonstrating our method's robustness and computational efficiency, we model perfect electric conductors (PECs) and silver nanocylinders, and we apply our approach to analyze the excited electric field on subtly distorted metallic surfaces, particularly plasmonic structures, thereby validating its wide-ranging effectiveness.

12.
Prehosp Emerg Care ; 28(5): 669-679, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820136

RESUMEN

OBJECTIVE: Various prediction scores have been developed to predict mortality in trauma patients, such as the shock index (SI), modified SI (mSI), age-adjusted SI (aSI), and the shock index (SI) multiplied by the alert/verbal/painful/unresponsive (AVPU) score (SIAVPU). The SIAVPU is a novel scoring system but its prediction accuracy for trauma outcomes remains in need of further validation. Therefore, we investigated the accuracy of four scoring systems, including SI, mSI, aSI, and SIAVPU, in predicting mortality, admission to the intensive care unit (ICU), and prolonged hospital length of stay ≥ 30 days (LOS). METHODS: This retrospective multicenter study used data from the Tzu Chi Hospital trauma database. The area under the receiver operating characteristic curve (AUROC) was determined for each outcome to assess their discrimination capabilities and comparing by Delong's test. Subgroup analyses were conducted to investigate the prediction accuracy of the SIAVPU in different patient populations. RESULTS: In total, 5355 patients were included in the analysis. The median of SIAVPU were significantly higher among patients at those with major injury (1.47 vs 0.63), those admitted to the ICU (0.73 vs 0.62), those with prolonged hospital LOS≥ 30 days (0.83 vs 0.64), and those with mortality (1.08 vs 0.64). The AUROC of the SIAVPU was significantly higher than that of the SI, mSI, and aSI for 24-h mortality (AUROC: 0.845 vs 0.533, 0.540, and 0.678), 3-day mortality (AUROC: 0.803 vs 0.513, 0.524, and 0.688), 7-day mortality (AUROC: 0.755 vs 0.494, 0.505, and 0.648), in-hospital mortality (AUROC: 0.722 vs 0.510, 0.524, and 0.667), ICU admission (AUROC: 0.635 vs 0.547, 0.551, and 0.563). At the optimal cutoff value of 0.9, the SIAVPU had an accuracy of 82.2% for predicting 24-h mortality, 82.8% for predicting 3-day mortality, of 82.8% for predicting 7-day mortality, of 82.5% for predicting in-hospital mortality, of 73.9% for predicting Intensive Care Unit (ICU) admission, and of 81.7% for predicting prolonged hospital LOS ≥30 days. CONCLUSIONS: Our results reveal that SIAVPU has better accuracy than the SI, mSI, and aSI for predicting 24-h, 3-day, 7-day, and in-hospital mortality; ICU admission; and prolonged hospital LOS ≥30 days among patients with traumatic injury.


Asunto(s)
Heridas y Lesiones , Humanos , Estudios Retrospectivos , Masculino , Femenino , Heridas y Lesiones/mortalidad , Persona de Mediana Edad , Adulto , Servicios Médicos de Urgencia , Tiempo de Internación/estadística & datos numéricos , Valor Predictivo de las Pruebas , Anciano , Unidades de Cuidados Intensivos/estadística & datos numéricos , Choque/mortalidad , Curva ROC , Puntaje de Gravedad del Traumatismo , Mortalidad Hospitalaria
13.
Nucleic Acids Res ; 50(4): 2190-2200, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35100402

RESUMEN

Unlike many other aminoacyl-tRNA synthetases, alanyl-tRNA synthetase (AlaRS) retains a conserved prototype structure throughout biology. While Caenorhabditis elegans cytoplasmic AlaRS (CeAlaRSc) retains the prototype structure, its mitochondrial counterpart (CeAlaRSm) contains only a residual C-terminal domain (C-Ala). We demonstrated herein that the C-Ala domain from CeAlaRSc robustly binds both tRNA and DNA. It bound different tRNAs but preferred tRNAAla. Deletion of this domain from CeAlaRSc sharply reduced its aminoacylation activity, while fusion of this domain to CeAlaRSm selectively and distinctly enhanced its aminoacylation activity toward the elbow-containing (or L-shaped) tRNAAla. Phylogenetic analysis showed that CeAlaRSm once possessed the C-Ala domain but later lost most of it during evolution, perhaps in response to the deletion of the T-arm (part of the elbow) from its cognate tRNA. This study underscores the evolutionary gain of C-Ala for docking AlaRS to the L-shaped tRNAAla.


Asunto(s)
Alanina-ARNt Ligasa , Aminoacil-ARNt Sintetasas , Alanina-ARNt Ligasa/genética , Aminoacil-ARNt Sintetasas/genética , Aminoacilación , Filogenia , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , ARN de Transferencia de Alanina/genética
14.
Nucleic Acids Res ; 50(17): 10015-10025, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36107775

RESUMEN

tRNAHis guanylyltransferase (Thg1) catalyzes the 3'-5' incorporation of guanosine into position -1 (G-1) of tRNAHis. G-1 is unique to tRNAHis and is crucial for recognition by histidyl-tRNA synthetase (HisRS). Yeast Thg1 requires ATP for G-1 addition to tRNAHis opposite A73, whereas archaeal Thg1 requires either ATP or GTP for G-1 addition to tRNAHis opposite C73. Paradoxically, human Thg1 (HsThg1) can add G-1 to tRNAsHis with A73 (cytoplasmic) and C73 (mitochondrial). As N73 is immediately followed by a CCA end (positions 74-76), how HsThg1 prevents successive 3'-5' incorporation of G-1/G-2/G-3 into mitochondrial tRNAHis (tRNAmHis) through a template-dependent mechanism remains a puzzle. We showed herein that mature native human tRNAmHis indeed contains only G-1. ATP was absolutely required for G-1 addition to tRNAmHis by HsThg1. Although HsThg1 could incorporate more than one GTP into tRNAmHisin vitro, a single-GTP incorporation prevailed when the relative GTP level was low. Surprisingly, HsThg1 possessed a tRNA-inducible GTPase activity, which could be inhibited by ATP. Similar activity was found in other high-eukaryotic dual-functional Thg1 enzymes, but not in yeast Thg1. This study suggests that HsThg1 may downregulate the level of GTP through its GTPase activity to prevent multiple-GTP incorporation into tRNAmHis.


Asunto(s)
Nucleotidiltransferasas/metabolismo , ARN de Transferencia de Histidina , Adenosina Trifosfato , GTP Fosfohidrolasas/genética , Guanosina , Guanosina Trifosfato/metabolismo , Histidina-ARNt Ligasa , Humanos , ARN de Transferencia , ARN de Transferencia de Histidina/genética , ARN de Transferencia de Histidina/metabolismo , Saccharomyces cerevisiae/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-39218767

RESUMEN

OBJECTIVES: To compare the success and complication rates of radial artery catheterization using ultrasound guidance versus the conventional palpation technique in obese patients by anesthesia residents with similar levels of experience in both methods, and to measure the skin-to-artery distance of radial, brachial, and dorsalis pedis arteries using ultrasound with standardized anatomic landmarks. DESIGN: Prospective, randomized controlled trial SETTING: Single tertiary center PARTICIPANTS: Eighty adults with a body mass index (BMI) ≥30 kg/m2 INTERVENTIONS: Ultrasound guidance or conventional palpation method MEASUREMENTS AND MAIN RESULTS: The primary outcome was the first-attempt success rate of arterial catheterization. The skin-to-artery distance of the radial artery was significantly greater in the BMI groups of 40 to 49 kg/m2 and ≥50 kg/m2 compared to the BMI group of 30 to 39 kg/m2 (mean difference, 1.0 mm; 95% confidence interval [CI], 0.4-1.7; p = 0.0029) for BMI 40-49 kg/m2 vs 30-39 kg/m2 and 1.5 mm (95% CI, 0.6-2.4 mm; p = 0.0015) for ≥50 kg/m2 vs 30-39 kg/m2. Similar findings were observed for the brachial artery. BMI was inversely associated with first-attempt success rates (p = 0.0145) and positively with time to successful catheterization (p = 0.0271). The first-attempt success and vascular complication rates of catheterization did not differ significantly between the ultrasound guidance group (65.0% and 52.5%, respectively) and the conventional palpation group (70.0% [p = 0.6331] and 57.5% [p = 0.6531], respectively). CONCLUSION: The results of this study do not support the routine use of ultrasonography during radial arterial catheterizations for obese adults when junior practitioners perform the procedure.

16.
PLoS Genet ; 17(12): e1009969, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34962934

RESUMEN

Teleosts live in aquatic habitats, where they encounter ionic and acid-base fluctuations as well as infectious pathogens. To protect from these external challenges, the teleost epidermis is composed of living cells, including keratinocytes and ionocytes that maintain body fluid ionic homeostasis, and mucous cells that secret mucus. While ionocyte progenitors are known to be specified by Delta-Notch-mediated lateral inhibition during late gastrulation and early segmentation, it remains unclear how epidermal mucous cells (EMCs) are differentiated and maintained. Here, we show that Delta/Jagged-mediated activation of Notch signaling induces the differentiation of agr2-positive (agr2+) EMCs in zebrafish embryos during segmentation. We demonstrated that agr2+ EMCs contain cytoplasmic secretory granules and express muc5.1 and muc5.2. Reductions in agr2+ EMC number were observed in mib mutants and notch3 MOs-injected notch1a mutants, while increases in agr2+ cell number were detected in notch1a- and X-Su(H)/ANK-overexpressing embryos. Treatment with γ-secretase inhibitors further revealed that Notch signaling is required during bud to 15 hpf for the differentiation of agr2+ EMCs. Increased agr2+ EMC numbers were also observed in jag1a-, jag1b-, jag2a- and dlc-overexpressing, but not jag2b-overexpressing embryos. Meanwhile, reductions in agr2+ EMC numbers were detected in jag1a morphants, jag1b mutants, jag2a mutants and dlc morphants, but not jag2b mutants. Reduced numbers of pvalb8-positive epidermal cells were also observed in mib or jag2a mutants and jag1a or jag1b morphants, while increased pvalb8-positive epidermal cell numbers were detected in notch1a-overexpressing, but not dlc-overexpressing embryos. BrdU labeling further revealed that the agr2+ EMC population is maintained by proliferation. Cell lineage experiments showed that agr2+ EMCs are derived from the same ectodermal precursors as keratinocytes or ionocytes. Together, our results indicate that specification of agr2+ EMCs in zebrafish embryos is induced by DeltaC/Jagged-dependent activation of Notch1a/3 signaling, and the cell population is maintained by proliferation.


Asunto(s)
Desarrollo Embrionario/genética , Proteínas de Homeodominio/genética , Proteína Jagged-1/genética , Proteína Jagged-2/genética , Proteínas del Tejido Nervioso/genética , Receptor Notch1/genética , Proteínas de Pez Cebra/genética , Animales , Proteínas de Unión al Calcio/genética , Diferenciación Celular/genética , Ectodermo/crecimiento & desarrollo , Epidermis/crecimiento & desarrollo , Queratinocitos/citología , Queratinocitos/metabolismo , Moco/metabolismo , Proteínas Mutantes/genética , Receptores Notch/genética , Transducción de Señal/genética , Pez Cebra/genética , Pez Cebra/crecimiento & desarrollo
17.
Reprod Domest Anim ; 59(8): e14698, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39073134

RESUMEN

The objective of the present study was to investigate the association among the largest follicle (LF), preovulatory estradiol (E2), and predominant vaginal epithelial cell at the completion of hormonal ovarian stimulation for fixed-time artificial insemination (FTAI) in goats. Thirty-seven crossbred Boer does received gonadotropin-releasing hormone (GnRH) and intravaginal progesterone (P4)-releasing devices (day 0). On day 5, P4 devices were removed and does received prostaglandin F2α and equine chorionic gonadotrophin. On day 7, does received GnRH, and FTAI was undertaken. On day 7, does were divided into three groups, i.e. small-sized (3-3.9 mm; n = 5), medium-sized (4-4.9 mm; n = 8), and large-sized (≥5 mm; n = 24) according to the diameter of the ovarian LF; follicular characteristics (number and diameter) were identified, and blood samples and vaginal smears were collected. The average diameters of total antral follicles and LF and the percentage of superficial cell were greatest in large-sized LF does (p < .01). The average diameters of total antral follicle (r = .68) and LF (r = .71), number of preovulatory follicle (r = .58), and plasma E2 concentrations (r = .61) were positively correlated with the percentage of superficial cells (p < .01). The likelihood of a pregnancy outcome after the FTAI increased by 13.71 times in does with a greater average diameter of antral follicle, 14.18 times with emergence of a large preovulatory follicle, and 36.83 times with a higher percentage of vaginal superficial cells (p < .01). It was concluded that there is a relationship between the cell types of the vaginal epithelium, the diameters of the largest ovarian follicles, and the concentration of E2 in goats subjected to FTAI protocols.


Asunto(s)
Células Epiteliales , Estradiol , Cabras , Inseminación Artificial , Folículo Ovárico , Inducción de la Ovulación , Progesterona , Vagina , Animales , Femenino , Cabras/fisiología , Estradiol/sangre , Folículo Ovárico/efectos de los fármacos , Inseminación Artificial/veterinaria , Células Epiteliales/efectos de los fármacos , Progesterona/sangre , Embarazo , Inducción de la Ovulación/veterinaria , Inducción de la Ovulación/métodos , Hormona Liberadora de Gonadotropina/farmacología , Gonadotropina Coriónica/farmacología , Gonadotropina Coriónica/administración & dosificación , Dinoprost/farmacología , Dinoprost/administración & dosificación , Administración Intravaginal
18.
Microsurgery ; 44(4): e31186, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38716649

RESUMEN

INTRODUCTION: Free flap transfer for head and neck defects has gained worldwide acceptance. Because flap failure is a devastating outcome, studies have attempted to identify risk factors-including renal failure. We sought to determine whether end-stage renal disease (ESRD) patients undergoing dialysis are at increased risk of flap failure following microsurgical head and neck reconstruction. PATIENTS AND METHODS: The study's participants were patients who underwent free flap reconstruction in the head and neck region at Hualien Tzu Chi Hospital between January 2010 and December 2019. We used the National Health Insurance "Specific Diagnosis and Treatment Code" to identify patients undergoing dialysis; these patients comprised the dialysis group, whose members were matched to a non-dialysis group for age and gender. The dependent variables were flap survival rate, take-back rate, and flap failure risk between the dialysis and non-dialysis groups. RESULTS: We included 154 patients in the dialysis (n = 14) and non-dialysis (n = 140) groups. The groups were similar in terms of age and most comorbidities, except diabetes mellitus, hypertension, and coronary artery disease, which were more prevalent in the dialysis group. The dialysis and non-dialysis groups had similar flap survival rates (100% vs. 92.9%; p = .600). Twenty-three patients underwent take-back surgery, most in the non-dialysis group (14.3% vs. 15.0%; p = 1.000). Patients in the dialysis group were more likely to have prolonged intensive care unit stays; however, dialysis alone did not predict flap failure (OR: 0.83; p = .864). CONCLUSION: This study found no significant differences in free flap survival and take-back rates between patients with and without dialysis. Dialysis did not increase the risk of flap failure following microsurgical head and neck reconstruction in this study; however, prospective, randomized controlled trials are needed.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Fallo Renal Crónico , Microcirugia , Procedimientos de Cirugía Plástica , Diálisis Renal , Humanos , Masculino , Femenino , Fallo Renal Crónico/terapia , Fallo Renal Crónico/complicaciones , Persona de Mediana Edad , Colgajos Tisulares Libres/trasplante , Procedimientos de Cirugía Plástica/métodos , Microcirugia/métodos , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias de Cabeza y Cuello/complicaciones , Anciano , Estudios Retrospectivos , Supervivencia de Injerto , Factores de Riesgo , Adulto
19.
Nano Lett ; 23(7): 2522-2529, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36975126

RESUMEN

Highly uniform quantum systems are essential for the practical implementation of scalable quantum processors. While quantum dot spin qubits based on semiconductor technology are a promising platform for large-scale quantum computing, their small size makes them particularly sensitive to their local environment. Here, we present a method to electrically obtain a high degree of uniformity in the intrinsic potential landscape using hysteretic shifts of the gate voltage characteristics. We demonstrate the tuning of pinch-off voltages in quantum dot devices over hundreds of millivolts that then remain stable at least for hours. Applying our method, we homogenize the pinch-off voltages of the plunger gates in a linear array for four quantum dots, reducing the spread in pinch-off voltages by one order of magnitude. This work provides a new tool for the tuning of quantum dot devices and offers new perspectives for the implementation of scalable spin qubit arrays.

20.
BMC Nurs ; 23(1): 713, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39363325

RESUMEN

BACKGROUND: Intensive care units are critical environments where various alarm systems play a pivotal role in patient monitoring and safety. Alarm fatigue can lead to slower response times and missed alarms, compromising patient safety and increasing stress and burnout among intensive care unit nurses. Understanding how intensive care unit nurses respond to and manage these alarms is crucial in evaluating their impact on patient care and nursing well-being. METHODS: This descriptive qualitative study explored the experiences of intensive care unit nurses in alarm management. Conducted in the medical and surgical intensive care units of a Northern Taiwan medical center, the study involved 15 nurses. Semi-structured interviews were utilized to investigate the working experiences of ICU nurses in alarm management and to identify their coping strategies for dealing with the constant inundation of medical device alarms. The interviews were transcribed, and content analysis was applied to identify key themes in the responses. RESULTS: The study revealed five main themes in intensive care unit nurses' strategies for managing alarms: (1) Mastering alarm signals and acting; (2) Team monitoring for life preservation; (3) Enhancing senses and distinguishing carefully; (4) Learning from the lessons of incidents for vigilant reflection; and (5) Detach alarms' influence on daily life. These coping strategies are effective in alarm management, safeguarding patients' lives, enhancing the serenity of the clinical environment, and mitigating the physical and mental exhaustion caused by alarm fatigue. CONCLUSIONS: Intensive Care Unit nurses develop various coping strategies to manage medical device alarms, based on their experience. These strategies are crucial in maintaining patient safety and reducing nurse alarm fatigue. They can also be used for nursing education and clinical training.

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