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1.
Cell ; 183(3): 684-701.e14, 2020 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-33058756

RESUMEN

Positive selection in Europeans at the 2q21.3 locus harboring the lactase gene has been attributed to selection for the ability of adults to digest milk to survive famine in ancient times. However, the 2q21.3 locus is also associated with obesity and type 2 diabetes in humans, raising the possibility that additional genetic elements in the locus may have contributed to evolutionary adaptation to famine by promoting energy storage, but which now confer susceptibility to metabolic diseases. We show here that the miR-128-1 microRNA, located at the center of the positively selected locus, represents a crucial metabolic regulator in mammals. Antisense targeting and genetic ablation of miR-128-1 in mouse metabolic disease models result in increased energy expenditure and amelioration of high-fat-diet-induced obesity and markedly improved glucose tolerance. A thrifty phenotype connected to miR-128-1-dependent energy storage may link ancient adaptation to famine and modern metabolic maladaptation associated with nutritional overabundance.


Asunto(s)
Enfermedades Metabólicas/genética , MicroARNs/genética , Adipocitos Marrones/patología , Adiposidad , Alelos , Animales , Diferenciación Celular , Línea Celular , Células Cultivadas , Dieta Alta en Grasa , Metabolismo Energético , Epigénesis Genética , Sitios Genéticos , Glucosa/metabolismo , Homeostasis , Humanos , Hipertrofia , Resistencia a la Insulina , Leptina/deficiencia , Leptina/metabolismo , Masculino , Mamíferos/genética , Ratones Endogámicos C57BL , Ratones Obesos , MicroARNs/metabolismo , Obesidad/genética , Oligonucleótidos/metabolismo , Especificidad de la Especie
2.
EMBO J ; 41(6): e109102, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35146778

RESUMEN

The microbiome plays an important role in shaping plant growth and immunity, but few plant genes and pathways impacting plant microbiome composition have been reported. In Arabidopsis thaliana, the phosphate starvation response (PSR) was recently found to modulate the root microbiome upon phosphate (Pi) starvation through the transcriptional regulator PHR1. Here, we report that A. thaliana PHR1 directly binds to the promoters of rapid alkalinization factor (RALF) genes, and activates their expression under phosphate-starvation conditions. RALFs in turn suppress complex formation of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) receptor through FERONIA, a previously-identified PTI modulator that increases resistance to certain detrimental microorganisms. Suppression of immunity via the PHR1-RALF-FERONIA axis allows colonization by specialized root microbiota that help to alleviate phosphate starvation by upregulating the expression of PSR genes. These findings provide a new paradigm for coordination of host-microbe homeostasis through modulating plant innate immunity after environmental perturbations.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Microbiota , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Fosfatos/metabolismo , Inmunidad de la Planta/genética , Plantas/metabolismo , Factores de Transcripción/metabolismo
3.
Nano Lett ; 24(34): 10691-10698, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39158185

RESUMEN

Intersubband transition was recently discovered in colloidal nanoplatelets, but the associated intersubband carrier relaxation dynamics remains poorly understood. In particular, it is crucial to selectively excite the intersubband transition and to follow the hot electron dynamics in the absence of valence-band holes. This is achieved herein by exciting the predoped electrons in CdSe/ZnS nanoplatelets using near-infrared femtosecond pulses and monitoring nonequilibrium electron dynamics using broad-band visible pulses. We find that the n = 2 electrons relax to the n = 1 subband and establish a Fermi-Dirac distribution within 200 fs, and finally reach an equilibrium with the lattice within a few ps. The cooling dynamics depend mainly on the excitation fluence but weakly on the doping density and the lattice temperature. These characteristics are well captured by our numerical simulation that explicitly accounts for the state occupation effect and optical phonon scattering.

4.
Am J Physiol Cell Physiol ; 326(5): C1423-C1436, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38497113

RESUMEN

Nicotinamide adenine dinucleotide (NAD+) is a pivotal coenzyme, essential for cellular reactions, metabolism, and mitochondrial function. Depletion of kidney NAD+ levels and reduced de novo NAD+ synthesis through the tryptophan-kynurenine pathway are linked to acute kidney injury (AKI), whereas augmenting NAD+ shows promise in reducing AKI. We investigated de novo NAD+ biosynthesis using in vitro, ex vivo, and in vivo models to understand its role in AKI. Two-dimensional (2-D) cultures of human primary renal proximal tubule epithelial cells (RPTECs) and HK-2 cells showed limited de novo NAD+ synthesis, likely due to low pathway enzyme gene expression. Using three-dimensional (3-D) spheroid culture model improved the expression of tubular-specific markers and enzymes involved in de novo NAD+ synthesis. However, de novo NAD+ synthesis remained elusive in the 3-D spheroid culture, regardless of injury conditions. Further investigation revealed that 3-D cultured cells could not metabolize tryptophan (Trp) beyond kynurenine (KYN). Intriguingly, supplementation of 3-hydroxyanthranilic acid into RPTEC spheroids was readily incorporated into NAD+. In a human precision-cut kidney slice (PCKS) ex vivo model, de novo NAD+ synthesis was limited due to substantially downregulated kynurenine 3-monooxygenase (KMO), which is responsible for KYN to 3-hydroxykynurenine conversion. KMO overexpression in RPTEC 3-D spheroids successfully reinstated de novo NAD+ synthesis from Trp. In addition, in vivo study demonstrated that de novo NAD+ synthesis is intact in the kidney of the healthy adult mice. Our findings highlight disrupted tryptophan-kynurenine NAD+ synthesis in in vitro cellular models and an ex vivo kidney model, primarily attributed to KMO downregulation.NEW & NOTEWORTHY Nicotinamide adenine dinucleotide (NAD+) is essential in regulating mitochondrial function. Reduced NAD+ synthesis through the de novo pathway is associated with acute kidney injury (AKI). Our study reveals a disruption in de novo NAD+ synthesis in proximal tubular models, but not in vivo, attributed to downregulation of enzyme kynurenine 3-monooxygenase (KMO). These findings highlight a crucial role of KMO in governing de novo NAD+ biosynthesis within the kidney, shedding light on potential AKI interventions.


Asunto(s)
Células Epiteliales , Túbulos Renales Proximales , Quinurenina 3-Monooxigenasa , NAD , Triptófano , Animales , Humanos , Ratones , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Lesión Renal Aguda/enzimología , Línea Celular , Células Cultivadas , Células Epiteliales/metabolismo , Túbulos Renales Proximales/metabolismo , Quinurenina/metabolismo , Quinurenina 3-Monooxigenasa/metabolismo , Quinurenina 3-Monooxigenasa/genética , Ratones Endogámicos C57BL , NAD/metabolismo , NAD/biosíntesis , Triptófano/metabolismo
5.
Cancer Immunol Immunother ; 73(1): 12, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231411

RESUMEN

BACKGROUND: The introduction of the anti-PD-1 antibody has greatly improved the clinical outcomes of patients with non-small cell lung cancer (NSCLC). In this study, we retrospectively analyzed the efficacy of PD-1 antibody-based therapy in patients with locally advanced inoperable or metastatic NSCLC and reported an association between peripheral blood biomarkers and clinical response in these patients. METHODS: This single-center study included medical record data of patients with NSCLC treated with the PD-1 antibody as a first-line or subsequent line of treatment, either as monotherapy or in combination with chemotherapy. The patients were enrolled from 2020 to 2022. We dynamically evaluated multiple Th1 and Th2 cytokines in the blood serum and analyzed the phenotype of T cells from the peripheral blood to explore the correlation between cytokine levels, T cell phenotypes, and clinical response. RESULTS: A total of 88 patients with stage IIIA-IV NSCLC were enrolled, out of which 60 (68.18%) achieved a partial response (PR), 13 (14.77%) had stable disease (SD), and 15 (17.05%) experienced disease progression (PD). The disease control rate was 82.95%. Our results suggested a significant reduction (P = 0.002, P < 0.005) in lymphocyte absolute counts after treatment in patients with PD. Higher levels of IFN-γ (P = 0.023, P < 0.05), TNF-α (P = 0.00098, P < 0.005), IL-4 (P = 0.0031, P < 0.005), IL-5 (P = 0.0015, P < 0.005), and IL-10 (P = 0.036, P < 0.05) were detected in the peripheral blood before treatment in the PR group compared to the PD group. Moreover, patients with high levels of IL-5, IL-13, IL-4, IL-6, IFN-γ, and TNF-α (> 10 ng/mL) had superior progression-free survival compared to those with low levels (< 10 ng/mL). Furthermore, PD-1 expression on CD8+ T cells was higher in patients who showed a PR than in those who did not show a response (SD + PD; P = 0.042, P < 0.05). CONCLUSIONS: The findings of this study imply that the decrease in absolute blood lymphocyte counts after treatment is correlated with disease progression. Serum cytokine levels may predict the effectiveness and survival rates of anti-PD-1 blockade therapy in patients with NSCLC. In addition, PD-1 expression on CD8+ T cells was positively associated with better clinical response. Our findings highlight the potential of peripheral blood biomarkers to predict the effectiveness of PD-1-targeted treatments in patients with NSCLC. Larger prospective studies are warranted to further clarify the value of these biomarkers.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Linfocitos T CD8-positivos , Interleucina-4 , Interleucina-5 , Receptor de Muerte Celular Programada 1 , Estudios Retrospectivos , Factor de Necrosis Tumoral alfa , Neoplasias Pulmonares/tratamiento farmacológico , Biomarcadores , Citocinas , Progresión de la Enfermedad
6.
Small ; 20(34): e2400850, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38616735

RESUMEN

Membrane-based osmotic energy harvesting is a promising technology with zero carbon footprint. High-performance ion-selective membranes (ISMs) are the core components in such applications. Recent advancement in 2D nanomaterials opens new avenues for building highly efficient ISMs. However, the majority of the explored 2D nanomaterials have a negative surface charge, which selectively enhances cation transport, resulting in the underutilization of half of the available ions. In this study, ISMs based on layered double hydroxide (LDH) with tunable positive surface charge are studied. The membranes preferentially facilitate anion transport with high selectivity. Osmotic energy harvesting device based on these membranes reached a power density of 2.31 W m-2 under simulated river/sea water, about eight times versus that of a commercial membrane tested under the same conditions, and up to 7.05 W m-2 under elevated temperature and simulated brine/sea water, and long-term stability with consistent performance over a 40-day period. A prototype reverse electrodialysis energy harvesting device, comprising a pair of LDH membranes and commercial cation-selective membranes, is able to simultaneously harvest energy from both cations and anions achieving a power density of 6.38 W m-2 in simulated river/sea water, demonstrating its potential as building blocks for future energy harvesting systems.

7.
Small ; : e2402845, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38895955

RESUMEN

Metal chalcogenides as an ideal family of anode materials demonstrate a high theoretical specific capacity for potassium ion batteries (PIBs), but the huge volume variance and poor cyclic stability hinder their practical applications. In this study, a design of a stress self-adaptive structure with ultrafine SnSe nanoparticles embedded in carbon nanofiber (SnSe@CNF) via the electrospinning technology is presented. Such an architecture delivers a record high specific capacity (272 mAh g-1 at 50 mA g-1) and high-rate performance (125 mAh g-1 at 1 A g-1) as a PIB anode. It is decoded that the fundamental understanding for this great performance is that the ultrafine SnSe particles enhance the full utilization of the active material and achieve stress relief as the stored strain energy from cycling is insufficient to drive crack propagation and thus alleviates the intrinsic chemo-mechanical degradation of metal chalcogenides.

8.
Opt Lett ; 49(15): 4090-4093, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090868

RESUMEN

This paper presents a glint correction algorithm for high spatial resolution optical remote sensing imagery captured by the ER-2 Airborne Visual Infrared Imaging Spectrometer (AVIRIS). The algorithm employs linear and differential techniques to mitigate sun glint and sky glint effects, encompassing statistical glint reflections resulting from variations in imaging angles within strips and inter-strip variations due to Fresnel reflectance disparities. It aims to diminish Fresnel reflectance diversity on water surfaces and mitigate the distortions induced by glint reflectance during spectral and ocean color inversion. A comparative analysis of spectral and ocean color information in AVIRIS images before and after correction reveals enhanced accuracy following the glint correction. By systematically addressing multiple glint reflections and their ramifications, this method offers a valuable framework for correcting water surface glint in diverse high spatial resolution optical imagery.

9.
Phys Rev Lett ; 132(3): 035102, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307060

RESUMEN

We report the first experimental observation on the reduction of backward scatterings by an instantaneous broadband laser with 0.6% bandwidth in conditions of interest for inertial confinement fusion at the low-coherence Kunwu laser facility. The backscatter of stimulated Brillouin scattering (SBS) was robustly reduced by half at intensities of 1-5×10^{14} W/cm^{2} with the 0.53-µm broadband laser in comparison with the monochromatic laser. As SBS dominates energy loss of laser-plasma interactions, the reduction of that demonstrates the enhancement of laser-target coupling by the use of broadband laser. The mitigation of filamentation leads to the reduction of stimulated Raman backscattering at low intensities. In addition, the three-halves harmonic emission was reduced with the broadband laser as well.

10.
Neurochem Res ; 49(5): 1123-1136, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38337135

RESUMEN

The brain's ventricles are filled with a colorless fluid known as cerebrospinal fluid (CSF). When there is an excessive accumulation of CSF in the ventricles, it can result in high intracranial pressure, ventricular enlargement, and compression of the surrounding brain tissue, leading to potential damage. This condition is referred to as hydrocephalus. Hydrocephalus is classified into two categories: congenital and acquired. Congenital hydrocephalus (CH) poses significant challenges for affected children and their families, particularly in resource-poor countries. Recognizing the psychological and economic impacts is crucial for developing interventions and support systems that can help alleviate the distress and burden faced by these families. As our understanding of CSF production and circulation improves, we are gaining clearer insights into the causes of CH. In this article, we will summarize the current knowledge regarding CSF circulation pathways and the underlying causes of CH. The main causes of CH include abnormalities in the FoxJ1 pathway of ventricular cilia, dysfunctions in the choroid plexus transporter Na+-K+-2Cl- contransporter isoform 1, developmental abnormalities in the cerebral cortex, and structural abnormalities within the brain. Understanding the causes of CH is indeed crucial for advancing research and developing effective treatment strategies. In this review, we will summarize the findings from existing studies on the causes of CH and propose potential research directions to further our understanding of this condition.


Asunto(s)
Hidrocefalia , Niño , Humanos , Hidrocefalia/líquido cefalorraquídeo , Hidrocefalia/patología , Encéfalo/patología , Plexo Coroideo/metabolismo , Plexo Coroideo/patología , Cabeza , Líquido Cefalorraquídeo
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