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1.
Nature ; 608(7922): 413-420, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35922515

RESUMEN

High cholesterol is a major risk factor for cardiovascular disease1. Currently, no drug lowers cholesterol through directly promoting cholesterol excretion. Human genetic studies have identified that the loss-of-function Asialoglycoprotein receptor 1 (ASGR1) variants associate with low cholesterol and a reduced risk of cardiovascular disease2. ASGR1 is exclusively expressed in liver and mediates internalization and lysosomal degradation of blood asialoglycoproteins3. The mechanism by which ASGR1 affects cholesterol metabolism is unknown. Here, we find that Asgr1 deficiency decreases lipid levels in serum and liver by stabilizing LXRα. LXRα upregulates ABCA1 and ABCG5/G8, which promotes cholesterol transport to high-density lipoprotein and excretion to bile and faeces4, respectively. ASGR1 deficiency blocks endocytosis and lysosomal degradation of glycoproteins, reduces amino-acid levels in lysosomes, and thereby inhibits mTORC1 and activates AMPK. On one hand, AMPK increases LXRα by decreasing its ubiquitin ligases BRCA1/BARD1. On the other hand, AMPK suppresses SREBP1 that controls lipogenesis. Anti-ASGR1 neutralizing antibody lowers lipid levels by increasing cholesterol excretion, and shows synergistic beneficial effects with atorvastatin or ezetimibe, two widely used hypocholesterolaemic drugs. In summary, this study demonstrates that targeting ASGR1 upregulates LXRα, ABCA1 and ABCG5/G8, inhibits SREBP1 and lipogenesis, and therefore promotes cholesterol excretion and decreases lipid levels.


Asunto(s)
Receptor de Asialoglicoproteína , Colesterol , Metabolismo de los Lípidos , Proteínas Quinasas Activadas por AMP/metabolismo , Transportador 1 de Casete de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 5 , Transportador de Casete de Unión a ATP, Subfamilia G, Miembro 8 , Receptor de Asialoglicoproteína/antagonistas & inhibidores , Receptor de Asialoglicoproteína/deficiencia , Receptor de Asialoglicoproteína/genética , Receptor de Asialoglicoproteína/metabolismo , Asialoglicoproteínas/metabolismo , Atorvastatina/farmacología , Proteína BRCA1 , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , Colesterol/metabolismo , Sinergismo Farmacológico , Endocitosis , Ezetimiba/farmacología , Humanos , Lípidos/análisis , Lípidos/sangre , Hígado/metabolismo , Receptores X del Hígado/metabolismo , Lisosomas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Ubiquitina-Proteína Ligasas/metabolismo
2.
BMC Plant Biol ; 24(1): 862, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39271987

RESUMEN

Drought poses a significant ecological threat that limits the production of crops worldwide. The objective of this study to examine the impact of soil applied biochar (BC) and peatmoss (PM) on the morpho-biochemical and quality traits of tobacco plants under drought conditions. In the present experiment work, a pot trial was conducted with two levels of drought severity (~ well-watered 75 ± 5% field capacity) and severe drought stress (~ 35 ± 5% field capacity), two levels of peatmoss (PM) @ 5% [PM+ (with peatmoss) and PM- (without peatmoss)] and three levels of rice straw biochar (BC0 = no biochar; BC1 = 150 mg kg- 1; and BC2 = 300 mg kg- 1 of soil) in tobacco plants. The results indicate that drought conditions significantly impacted the performance of tobacco plants. However, the combined approach of BC and PM significantly improved the growth, biomass, and total chlorophyll content (27.94%) and carotenoids (32.00%) of tobacco. This study further revealed that the drought conditions decreased the production of lipid peroxidation and proline accumulation. But the synergistic approach of BC and PM application increased soluble sugars (17.63 and 12.20%), soluble protein (31.16 and 15.88%), decreased the proline accumulation (13.92 and 9.03%), and MDA content (16.40 and 8.62%) under control and drought stressed conditions, respectively. Furthermore, the combined approach of BC and PM also improved the leaf potassium content (19.02%) by limiting the chloride ions (33.33%) under drought stressed conditions. Altogether, the balanced application of PM and BC has significant potential as an effective approach and sustainable method to increase the tolerance of tobacco plants subjected to drought conditions. This research uniquely highlights the combined potential of PM and BC as an eco-friendly strategy to enhance plant resilience under drought conditions, offering new insights into sustainable agricultural practices.


Asunto(s)
Carbón Orgánico , Nicotiana , Sphagnopsida , Nicotiana/crecimiento & desarrollo , Nicotiana/fisiología , Fotosíntesis , Especies Reactivas de Oxígeno , Metabolismo de los Lípidos , Hojas de la Planta , Análisis de Componente Principal , Sequías , Agua
3.
Opt Express ; 32(4): 5908-5921, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439306

RESUMEN

We present an all-fiber passively mode-locked (ML) laser with a nonlinear multimode interference (NLMI)-based saturable absorber (SA) capable of generating five pulse modes. The SA consists of two centrally aligned graded index multimode fiber (GIMF) with different diameters (105-50 µm) and features a widely adjustable transmission with saturable/reverse-saturable absorption. Based on this, dissipative soliton (DS), Q-switched rectangular pulse (QRP), dissipative soliton resonance (DSR), noise-like pulse (NLP) and bright-dark pulse pairs (BDP) are observed at three dispersions without additional filter. The DS has a pulse energy, bandwidth and duration of up to 1.15 nJ, 17.98 nm and ∼2.78 ps. The achievable pulse duration and energy of DSR and NLP are 5.21, 48.06 ns and 4.53, 5.12 nJ, respectively. Furthermore, it is demonstrated that the BDP is superimposed by a chair-case pulse (CP) and a rectangular pulse (RP) belonging to orthogonal polarization states. The versatility, flexibility, simplicity and energy scalability of the large-core hybrid GIMF-SA, make it interesting and highly attractive in ultrafast photonics.

4.
Transfus Apher Sci ; 63(4): 103942, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815499

RESUMEN

Blood transfusion in critically ill individuals such as sepsis was associated with higher morbidity and mortality. During storage, various bioactive substances accumulated, may exacerbate the initial immunosuppressive reaction in severely ill patients. The objective of this study is to explore how resin adsorption impacts the accumulation of cytokines and the presence of extracellular microvesicles (EVs) in whole blood. Through comparative analysis and screening, amberchrom CG 300 C was chosen to assess the adsorption efficiency and evaluate the quality of whole blood after adsorption. Subsequently, the supernatants from both the unadsorpted (UA) and adsorpted (A) groups were co-cultured with peripheral blood mononuclear cells (PBMCs) to assess their effects on cellular growth and cytokine concentrations. The findings of our study revealed that resin adsorption effectively eradicated most bioactive components in conserved blood, including IL-8, TGF-ß, sCD40L, sFasL, without affecting the quality of the blood. Furthermore, scanning electron microscopy (SEM) revealed a reduction in extracellular microvesicles following adsorption. Compared to UA, A 's supernatant markedly enhanced PBMC growth (p < 0.01). Additionally, the A's supernatant markedly diminished the emission of pro-inflammatory cytokines, like IL-6. The research revealed that adsorbing resin effectively reduced bioactive substances from preserved whole blood, and did not impact red blood cell quality, proving to be a reliable method for extracting bioactive substances from storage blood. The results could pave the way for creating innovative blood bags and hold clinical significance in lowering the frequency of TRIM among patients who have undergone transfusions.


Asunto(s)
Citocinas , Humanos , Citocinas/metabolismo , Citocinas/sangre , Adsorción , Conservación de la Sangre/métodos , Masculino , Femenino
5.
Ann Vasc Surg ; 100: 39-46, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38104925

RESUMEN

BACKGROUND: To evaluate the safety and efficacy of endovascular denervation (EDN) as an adjunct to percutaneous vascular intervention (PVI) for peripheral artery disease (PAD). METHODS: From August 2019 to April 2021, 38 eligible patients with PAD enrolled in this study were randomly and equally assigned into 2 groups: the PVI group and the PVI + EDN group treated with EDN at the iliac and femoral arteries before PVI. The primary endpoint was the improvement in the ankle brachial index at 6 months after the procedure. The secondary endpoints were transcutaneous oxygen pressure (TcPO2), Rutherford category, numerical rating scale score, and safety. RESULTS: The technical success rates of PVI and EDN were 100%, and no device-related or procedure-related major adverse events occurred in either group. Compared with PVI alone, PVI + EDN demonstrated a significant improvement in limb hemodynamics at 6 months (Δ ankle brachial index 0.44 ± 0.31 vs. 0.24 ± 0.15, P = 0.018). Microcirculatory perfusion of PAD was significantly better at 6 months in the PVI + EDN group (ΔTcPO2, 15.68 ± 16.72 vs. 4.95 ± 13.43, P = 0.036). The Rutherford category was significantly improved in the PVI + EDN group in comparison with the PVI group at the 3-month follow-up (100.00% vs. 68.42%, P = 0.02). The decrease in the numerical rating scale score in the PVI + EDN group was greater than that in the PVI group at 1 week following the procedure (3 [2-5] vs. 4 [4-6], P = 0.022). CONCLUSIONS: In this single-center pilot analysis of a heterogeneous cohort of patients with PAD, PVI with EDN demonstrated a significant improvement in limb ischemia at 6 months compared with PVI alone.


Asunto(s)
Procedimientos Endovasculares , Enfermedad Arterial Periférica , Humanos , Microcirculación , Resultado del Tratamiento , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/cirugía , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Desnervación , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Factores de Riesgo
6.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34417312

RESUMEN

Interactions of electronic and vibrational degrees of freedom are essential for understanding excited-states relaxation pathways of molecular systems at interfaces and surfaces. Here, we present the development of interface-specific two-dimensional electronic-vibrational sum frequency generation (2D-EVSFG) spectroscopy for electronic-vibrational couplings for excited states at interfaces and surfaces. We demonstrate this 2D-EVSFG technique by investigating photoexcited interface-active (E)-4-((4-(dihexylamino) phenyl)diazinyl)-1-methylpyridin-1- lum (AP3) molecules at the air-water interface as an example. Our 2D-EVSFG experiments show strong vibronic couplings of interfacial AP3 molecules upon photoexcitation and subsequent relaxation of a locally excited (LE) state. Time-dependent 2D-EVSFG experiments indicate that the relaxation of the LE state, S2, is strongly coupled with two high-frequency modes of 1,529.1 and 1,568.1 cm-1 Quantum chemistry calculations further verify that the strong vibronic couplings of the two vibrations promote the transition from the S2 state to the lower excited state S1 We believe that this development of 2D-EVSFG opens up an avenue of understanding excited-state dynamics related to interfaces and surfaces.

7.
J Lipid Res ; 64(12): 100465, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37890669

RESUMEN

Accurate intracellular cholesterol traffic plays crucial roles. Niemann Pick type C (NPC) proteins NPC1 and NPC2, are two lysosomal cholesterol transporters that mediate the cholesterol exit from lysosomes. However, other proteins involved in this process remain poorly defined. Here, we find that the previously unannotated protein TMEM241 is required for cholesterol egressing from lysosomes through amphotericin B-based genome-wide CRISPR-Cas9 KO screening. Ablation of TMEM241 caused impaired sorting of NPC2, a protein utilizes the mannose-6-phosphate (M6P) modification for lysosomal targeting, resulting in cholesterol accumulation in the lysosomes. TMEM241 is a member of solute transporters 35 nucleotide sugar transporters family and localizes on the cis-Golgi network. Our data indicate that TMEM241 transports UDP-N-acetylglucosamine (UDP-GlcNAc) into Golgi lumen and UDP-GlcNAc is used for the M6P modification of proteins including NPC2. Furthermore, Tmem241-deficient mice display cholesterol accumulation in pulmonary cells and behave pulmonary injury and hypokinesia. Taken together, we demonstrate that TMEM241 is a Golgi-localized UDP-GlcNAc transporter and loss of TMEM241 causes cholesterol accumulation in lysosomes because of the impaired M6P-dependent lysosomal targeting of NPC2.


Asunto(s)
Colesterol , Proteínas de Transporte Vesicular , Animales , Ratones , Proteínas de Transporte Vesicular/metabolismo , Colesterol/metabolismo , Uridina Difosfato/metabolismo , Lisosomas/metabolismo
8.
Neuroimage ; 279: 120321, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37574119

RESUMEN

Accurate stroke assessment and consequent favorable clinical outcomes rely on the early identification and quantification of aneurysmal subarachnoid hemorrhage (aSAH) in non-contrast computed tomography (NCCT) images. However, hemorrhagic lesions can be complex and difficult to distinguish manually. To solve these problems, here we propose a novel Hybrid 2D/3D UNet deep-learning framework for automatic aSAH identification and quantification in NCCT images. We evaluated 1824 consecutive patients admitted with aSAH to four hospitals in China between June 2018 and May 2022. Accuracy and precision, Dice scores and intersection over union (IoU), and interclass correlation coefficients (ICC) were calculated to assess model performance, segmentation performance, and correlations between automatic and manual segmentation, respectively. A total of 1355 patients with aSAH were enrolled: 931, 101, 179, and 144 in four datasets, of whom 326 were scanned with Siemens, 640 with Philips, and 389 with GE Medical Systems scanners. Our proposed deep-learning method accurately identified (accuracies 0.993-0.999) and segmented (Dice scores 0.550-0.897) hemorrhage in both the internal and external datasets, even combinations of hemorrhage subtypes. We further developed a convenient AI-assisted platform based on our algorithm to assist clinical workflows, whose performance was comparable to manual measurements by experienced neurosurgeons (ICCs 0.815-0.957) but with greater efficiency and reduced cost. While this tool has not yet been prospectively tested in clinical practice, our innovative hybrid network algorithm and platform can accurately identify and quantify aSAH, paving the way for fast and cheap NCCT interpretation and a reliable AI-based approach to expedite clinical decision-making for aSAH patients.


Asunto(s)
Aprendizaje Profundo , Accidente Cerebrovascular , Hemorragia Subaracnoidea , Humanos , Hemorragia Subaracnoidea/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste
9.
J Neurochem ; 167(4): 489-504, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37823326

RESUMEN

Chronic cerebral hypoperfusion leads to sustained demyelination and a unique response of microglia. Triggering receptor expressed on myeloid cells 2 (Trem2), which is expressed exclusively on microglia in the central nervous system (CNS), plays an essential role in microglial response in various CNS disorders. However, the specific role of Trem2 in chronic cerebral hypoperfusion has not been elucidated. In this study, we investigated the specific role of Trem2 in a mouse model of chronic cerebral hypoperfusion induced by bilateral carotid artery stenosis (BCAS). Our results showed that chronic hypoperfusion induced white matter demyelination, microglial phagocytosis, and activation of the microglial autophagic-lysosomal pathway, accompanied by an increase in Trem2 expression. After Trem2 knockout, we observed attenuation of white matter lesions and microglial response. Trem2 deficiency also suppressed microglial phagocytosis and relieved activation of the autophagic-lysosomal pathway, leading to microglial polarization towards anti-inflammatory and homeostatic phenotypes. Furthermore, Trem2 knockout inhibited lipid droplet accumulation in microglia in vitro. Collectively, these findings suggest that Trem2 deficiency ameliorated microglial phagocytosis and autophagic-lysosomal activation in hypoperfusion-induced white matter injury, and could be a promising target for the treatment of chronic cerebral hypoperfusion.


Asunto(s)
Isquemia Encefálica , Enfermedades Desmielinizantes , Sustancia Blanca , Animales , Ratones , Sustancia Blanca/patología , Microglía/metabolismo , Fagocitosis , Isquemia Encefálica/metabolismo , Lisosomas/metabolismo , Enfermedades Desmielinizantes/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo
10.
J Neuroinflammation ; 20(1): 89, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37013543

RESUMEN

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disorder of the central nervous system (CNS) triggered by autoimmune mechanisms. Microglia are activated and play a pivotal role in response to tissue injury. Triggering receptor expressed on myeloid cells 2 (TREM2) is expressed by microglia and promotes microglial activation, survival and phagocytosis. Here, we identify a critical role for TREM2 in microglial activation and function during AQP4-IgG and complement-induced demyelination. TREM2-deficient mice had more severe tissue damage and neurological impairment, as well as fewer oligodendrocytes with suppressed proliferation and maturation. The number of microglia clustering in NMOSD lesions and their proliferation were reduced in TREM2-deficient mice. Moreover, morphology analysis and expression of classic markers showed compromised activation of microglia in TREM2-deficient mice, which was accompanied by suppressed phagocytosis and degradation of myelin debris by microglia. These results overall indicate that TREM2 is a key regulator of microglial activation and exert neuroprotective effects in NMOSD demyelination.


Asunto(s)
Glicoproteínas de Membrana , Microglía , Neuromielitis Óptica , Receptores Inmunológicos , Animales , Ratones , Sistema Nervioso Central , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Microglía/metabolismo , Vaina de Mielina/metabolismo , Neuromielitis Óptica/metabolismo , Fagocitosis/genética , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo
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