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1.
Cell ; 187(11): 2746-2766.e25, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38631355

RESUMEN

Precise control of gene expression levels is essential for normal cell functions, yet how they are defined and tightly maintained, particularly at intermediate levels, remains elusive. Here, using a series of newly developed sequencing, imaging, and functional assays, we uncover a class of transcription factors with dual roles as activators and repressors, referred to as condensate-forming level-regulating dual-action transcription factors (TFs). They reduce high expression but increase low expression to achieve stable intermediate levels. Dual-action TFs directly exert activating and repressing functions via condensate-forming domains that compartmentalize core transcriptional unit selectively. Clinically relevant mutations in these domains, which are linked to a range of developmental disorders, impair condensate selectivity and dual-action TF activity. These results collectively address a fundamental question in expression regulation and demonstrate the potential of level-regulating dual-action TFs as powerful effectors for engineering controlled expression levels.


Asunto(s)
Factores de Transcripción , Animales , Humanos , Ratones , Regulación de la Expresión Génica , Mutación , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Línea Celular
2.
Nature ; 618(7963): 193-200, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37225986

RESUMEN

Odorants are detected as smell in the nasal epithelium of mammals by two G-protein-coupled receptor families, the odorant receptors and the trace amine-associated receptors1,2 (TAARs). TAARs emerged following the divergence of jawed and jawless fish, and comprise a large monophyletic family of receptors that recognize volatile amine odorants to elicit both intraspecific and interspecific innate behaviours such as attraction and aversion3-5. Here we report cryo-electron microscopy structures of mouse TAAR9 (mTAAR9) and mTAAR9-Gs or mTAAR9-Golf trimers in complex with ß-phenylethylamine, N,N-dimethylcyclohexylamine or spermidine. The mTAAR9 structures contain a deep and tight ligand-binding pocket decorated with a conserved D3.32W6.48Y7.43 motif, which is essential for amine odorant recognition. In the mTAAR9 structure, a unique disulfide bond connecting the N terminus to ECL2 is required for agonist-induced receptor activation. We identify key structural motifs of TAAR family members for detecting monoamines and polyamines and the shared sequence of different TAAR members that are responsible for recognition of the same odour chemical. We elucidate the molecular basis of mTAAR9 coupling to Gs and Golf by structural characterization and mutational analysis. Collectively, our results provide a structural basis for odorant detection, receptor activation and Golf coupling of an amine olfactory receptor.


Asunto(s)
Aminas Biogénicas , Odorantes , Percepción Olfatoria , Poliaminas , Receptores Odorantes , Animales , Ratones , Aminas Biogénicas/análisis , Aminas Biogénicas/química , Aminas Biogénicas/metabolismo , Microscopía por Crioelectrón , Subunidades alfa de la Proteína de Unión al GTP Gs/química , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/ultraestructura , Odorantes/análisis , Percepción Olfatoria/fisiología , Poliaminas/análisis , Poliaminas/química , Poliaminas/metabolismo , Receptores de Amina Biogénica/química , Receptores de Amina Biogénica/genética , Receptores de Amina Biogénica/metabolismo , Receptores de Amina Biogénica/ultraestructura , Receptores Odorantes/química , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/ultraestructura , Olfato/fisiología , Espermidina/análisis , Espermidina/química , Espermidina/metabolismo
3.
Plant Cell ; 36(2): 367-382, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37930821

RESUMEN

The gaseous signaling molecule nitric oxide (NO) plays an important role in breaking seed dormancy. NO induces a decrease in abscisic acid (ABA) content by transcriptionally activating its catabolic enzyme, the ABA 8'-hydroxylase CYP707A2. However, the underlying mechanism of this process remains unclear. Here, we report that the transcription factor MYB30 plays a critical role in NO-induced seed germination in Arabidopsis (Arabidopsis thaliana). MYB30 loss-of-function attenuates NO-mediated seed dormancy breaking. MYB30 triggers a NO-induced decrease in ABA content during germination by directly promoting CYP707A2 expression. NO induces S-nitrosylation at Cys-49 of MYB30 and enhances its transcriptional activity. Conversely, the ABA receptors PYRABACTIN RESISTANCE1 (PYR1)/PYR1-LIKE (PYL)/REGULATORY COMPONENTS OF ABA RECEPTORS (RCAR) interact with MYB30 and repress its transcriptional activity. ABA promotes the interaction between PYL4 and MYB30, whereas S-nitrosylation releases the PYL4-mediated inhibition of MYB30 by interfering with the PYL4-MYB30 interaction. Genetic analysis showed that MYB30 functions downstream of PYLs during seed dormancy and germination in response to NO. Furthermore, MYB30 mutation significantly represses the reduced dormancy phenotype and the enhanced CYP707A2 expression of the pyr1 pyl1 pyl2 pyl4 quadruple mutant. Our findings reveal that S-nitrosylation of MYB30 precisely regulates the balance of seed dormancy and germination, providing insights into the underlying mechanism of NO-promoted seed germination.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Germinación , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Óxido Nítrico/metabolismo , Semillas/genética , Semillas/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas
4.
Nat Chem Biol ; 20(4): 484-492, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37945893

RESUMEN

GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14-GPR101-Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.


Asunto(s)
Receptores Acoplados a Proteínas G , Ratones , Animales , Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G/metabolismo , Ligandos
5.
Plant Physiol ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39217410

RESUMEN

Arabidopsis (Arabidopsis thaliana) H+-ATPase1 (AHA1), a plasma membrane (PM)-localized H+-ATPase, plays a key role in plant alkali stress tolerance by pumping protons from the cytoplasm to the apoplast. However, its molecular dynamics are poorly understood. We report that many C2-domain ABA-related (CAR) protein family members interact with AHA1 in Arabidopsis. Single or double mutants of CAR1, CAR6, and CAR10 had no obvious phenotype of alkali stress tolerance, while their triple mutants showed significantly higher tolerance to this stress. The disruption of AHA1 largely compromised the increased alkali stress tolerance of the car1car6car10 mutant, revealing a key role of CARs in AHA1 regulation during the plant's response to a high alkali pH. Furthermore, variable angle total internal reflection fluorescence microscopy was used to observe AHA1-mGFP5 in intact Arabidopsis seedlings, revealing the presence of heterogeneous diffusion coefficients and oligomerization states in the AHA1 spots. In the aha1 complementation lines, alkali stress curtailed the residence time of AHA1 at the PM and increased the diffusion coefficient and particle velocity of AHA1. In contrast, the absence of CAR proteins decreased the restriction of the dynamic behavior of AHA1. Our results suggest that CARs play a negative role in plant alkali stress tolerance by interacting with AHA1 and provide a perspective to investigate the regulatory mechanism of PM H+-ATPase activity at the single-particle level.

6.
Plant Cell ; 34(2): 927-944, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34865139

RESUMEN

High soil salinity negatively affects plant growth and development, leading to a severe decrease in crop production worldwide. Here, we report that a secreted peptide, PAMP-INDUCED SECRETED PEPTIDE 3 (PIP3), plays an essential role in plant salt tolerance through RECEPTOR-LIKE KINASE 7 (RLK7) in Arabidopsis (Arabidopsis thaliana). The gene encoding the PIP3 precursor, prePIP3, was significantly induced by salt stress. Plants overexpressing prePIP3 exhibited enhanced salt tolerance, whereas a prePIP3 knockout mutant had a salt-sensitive phenotype. PIP3 physically interacted with RLK7, a leucine-rich repeat RLK, and salt stress enhanced PIP3-RLK7 complex formation. Functional analyses revealed that PIP3-mediated salt tolerance is dependent on RLK7. Exogenous application of synthetic PIP3 peptide activated RLK7, and salt treatment significantly induced RLK7 phosphorylation in a PIP3-dependent manner. Notably, MITOGEN-ACTIVATED PROTEIN KINASE3 (MPK3) and MPK6 were downstream of the PIP3-RLK7 module in salt response signaling. Activation of MPK3/6 was attenuated in pip3 or rlk7 mutants under saline conditions. Therefore, MPK3/6 might amplify salt stress response signaling in plants for salt tolerance. Collectively, our work characterized a novel ligand-receptor signaling cascade that modulates plant salt tolerance in Arabidopsis. This study contributes to our understanding of how plants respond to salt stress.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Tolerancia a la Sal , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Plantas Modificadas Genéticamente , Estrés Salino/fisiología , Tolerancia a la Sal/fisiología
7.
Proc Natl Acad Sci U S A ; 119(15): e2117004119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35394864

RESUMEN

GPR126 is a member of the adhesion G protein-coupled receptors (aGPCRs) that is essential for the normal development of diverse tissues, and its mutations are implicated in various pathological processes. Here, through screening 34 steroid hormones and their derivatives for cAMP production, we found that progesterone (P4) and 17-hydroxyprogesterone (17OHP) could specifically activate GPR126 and trigger its downstream Gi signaling by binding to the ligand pocket in the seven-transmembrane domain of the C-terminal fragment of GPR126. A detailed mutagenesis screening according to a computational simulated structure model indicated that K1001ECL2 and F1012ECL2 are key residues that specifically recognize 17OHP but not progesterone. Finally, functional analysis revealed that progesterone-triggered GPR126 activation promoted cell growth in vitro and tumorigenesis in vivo, which involved Gi-SRC pathways in a triple-negative breast cancer model. Collectively, our work identified a membrane receptor for progesterone/17OHP and delineated the mechanisms by which GPR126 participated in potential tumor progression in triple-negative breast cancer, which will enrich our understanding of the functions and working mechanisms of both the aGPCR member GPR126 and the steroid hormone progesterone.


Asunto(s)
Progesterona , Receptores Acoplados a Proteínas G , Receptores de Progesterona , Neoplasias de la Mama Triple Negativas , 17-alfa-Hidroxiprogesterona/metabolismo , Línea Celular Tumoral , Humanos , Progesterona/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo
8.
Phys Rev Lett ; 132(25): 250204, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38996245

RESUMEN

The Hamiltonian, which determines the evolution of a quantum system, is fundamental in quantum physics. Therefore, it is crucial to implement high-precision generation and measurement of the Hamiltonian in a practical quantum system. Here, we experimentally demonstrate ultrahigh-precision Hamiltonian parameter estimation with a significant quantum advantage in a superconducting circuit via sequential control. We first observe the commutation relation for noncommuting operations determined by the system Hamiltonian, both with and without adding quantum control, verifying the commuting property of controlled noncommuting operations. Based on this control-induced commuting property, we further demonstrate Hamiltonian parameter estimation for polar and azimuth angles in superconducting circuits, achieving ultrahigh metrological gains in measurement precision exceeding the standard quantum limit by up to 16.0 and 16.1 dB at N=100, respectively.

9.
BMC Cancer ; 24(1): 1327, 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39472811

RESUMEN

Loss of ARID1A has been reported to drive the progression of lung adenocarcinoma, yet the underlying mechanism remains elusive. In this study, we performed secretome analysis to identify the key secreted proteins regulating lung adenocarcinoma progression. We showed that the VASN level was significantly elevated in the conditioned medium from ARID1A-depleted A549 and H1299 cells. Restoration of ARID1A in ARID1A-depleted lung adenocarcinoma cells prevented the upregulation and secretion of VASN. Clinical analysis demonstrated a negative correlation between ARID1A and VASN expression in ARID1A-mutated lung adenocarcinomas. The patients with ARID1A-mutated lung adenocarcinoma had significantly higher concentrations of serum VASN than healthy controls. Moreover, serum VASN concentrations were associated with TNM stage, lymph node metastasis, and overall survival of the patients with ARID1A-mutated lung adenocarcinoma. Functional studies indicated that VASN overexpression potentiated the proliferation, invasion, and tumorigenesis of lung adenocarcinoma cells. Antibody neutralization of VASN suppressed the aggressiveness of ARID1A-depleted lung adenocarcinoma cells both in vitro and in vivo. Addition of recombinant VASN protein promoted the proliferation and invasion of lung adenocarcinoma cells. Additionally, knockdown of Notch1 blocked the aggressive phenotype induced by recombinant VASN protein. In conclusion, our data uncover the role of VASN in mediating the progression of ARID1A-depleted lung adenocarcinoma and highlight VASN as a promising therapeutic target for this disease.


Asunto(s)
Adenocarcinoma del Pulmón , Proteínas de Unión al ADN , Neoplasias Pulmonares , Factores de Transcripción , Humanos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Ratones , Animales , Proliferación Celular , Fenotipo , Masculino , Femenino , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Mutación , Células A549 , Persona de Mediana Edad , Invasividad Neoplásica , Progresión de la Enfermedad
10.
Ann Hematol ; 103(11): 4649-4660, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38761184

RESUMEN

Bruton's tyrosine kinase inhibitors (BTKi) exhibit superior efficacy in relapsed/refractory primary central nervous system lymphoma (PCNSL), but few studies have evaluated patients with newly diagnosed PCNSL, and even fewer studies have evaluated differences in efficacy between treatment with BTKi and traditional chemotherapy. This study retrospectively analyzed the clinical characteristics of 86 patients with PCNSL and identified predictors of poor prognosis for overall survival (OS). After excluding patients who only received palliative care, 82 patients were evaluated for efficacy and survival. According to the induction regimen, patients were divided into the traditional chemotherapy, BTKi combination therapy, and radiotherapy groups; the objective response rates (ORR) of the three groups were 71.4%, 96.2%, and 71.4% (P = 0.037), respectively. Both median progression-free survival and median duration of remission showed statistically significant differences (P = 0.019 and P = 0.030, respectively). The median OS of the BTKi-containing therapy group was also longer than that of the traditional chemotherapy group (not reached versus 47.8 (32.5-63.1) months, P = 0.038).Seventy-one patients who achieved an ORR were further analyzed, and achieved an ORR after four cycles of treatment and maintenance therapy had prolonged OS (P = 0.003 and P = 0.043, respectively). In conclusion, survival, and prognosis of patients with newly diagnosed PCNSL are influenced by the treatment regimen, with the BTKi-containing regimen showing great potential.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Humanos , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias del Sistema Nervioso Central/mortalidad , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/terapia , Anciano , Adulto , Pronóstico , Anciano de 80 o más Años , Agammaglobulinemia Tirosina Quinasa/antagonistas & inhibidores , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Tasa de Supervivencia , Linfoma/diagnóstico , Linfoma/terapia , Linfoma/mortalidad , Linfoma/tratamiento farmacológico
11.
Gynecol Oncol ; 191: 95-99, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39378742

RESUMEN

OBJECTIVE: Patients with TNM T1a cervical cancer have excellent prognosis; however, the risk for recurrence remains an issue of concern and management guidelines are based on limited data. Here we performed subgroup analysis of the Surveillance in Cervical Cancer (SCCAN) consortium with the objective of defining the prognosis of T1a cervical cancer patients. METHODS: SCCAN was an international, multicentric, retrospective cohort study of patients with cervical cancer undergoing surgical treatment in tertiary centers. Inclusion criteria included: histologically confirmed cervical cancer treated between 2007 and 2016; TNM T1a; primary surgical management; and at least 1-year of follow-up data availability. Exclusion criteria included treatment with primary chemo-radiation, and missing treatment-related or clinical data. RESULTS: Out of 975 patients included, 554 (57 %) were T1a1 and 421 (43 %) T1a2. The majority had squamous-cell carcinoma (78 %). 79 patients (8.1 %) had lymphovascular space invasion (LVSI). 455 patients (47 %) underwent radical hysterectomy/ parametrectomy. Laparoscopic and open surgery was performed in 401 (41 %) and in 361 (37 %) patients, respectively. Adjuvant treatment was administered to 56 patients (5.7 %). Assessment of lymph nodes (LN) was performed in 524 patients (54 %), with LN involvement found in 15 (2.9 %). There were 40 (4.1 %) recurrences, occurring at a median of 26 months (4-106), out of which 33 (82.5 %) occurred in pelvis. Among T1a1 cases, there were 10 recurrences (2.0 %) if LVSI was negative, and 3 recurrences (6.7 %) if LVSI was positive. Among T1a2 cases, there were 23 recurrences (6.7 %) if LVSI was negative, and 4 recurrences (5.1 %) if LVSI was positive. There were 3 recurrences in the LN+ group (recurrence rate 20 %). CONCLUSIONS: The risk of recurrence in T1a cervical cancer was 4.1 % corresponding to the rates seen in patients with FIGO 1B cancer in recently published prospective trials. LN involvement represents a risk factor for disease recurrence. Our results indicate that stage T1a cervical cancer, apart from T1a1 LVSI negative disease, should follow the same principles in the management as that of FIGO stage 1B cancer.

12.
Eur Radiol ; 34(1): 226-235, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37552260

RESUMEN

OBJECTIVES: To evaluate the early prevalence of anthracycline-induced cardiotoxicity (AIC) and anthracycline-induced liver injury (AILI) using T2 and T2* mapping and to explore their correlations. MATERIALS AND METHODS: The study included 17 cardiotoxic rabbits that received weekly injections of doxorubicin and magnetic resonance imaging (MRI) every 2 weeks for 10 weeks. Cardiac function and T2 and T2* values were measured on each period. Histopathological examinations for two to five rabbits were performed after each MRI scan. The earliest sensitive time and the threshold of MRI parameters for detecting AIC and AILI based on these MRI parameters were obtained. Moreover, the relationship between myocardial and liver damage was assessed. RESULTS: Early AIC could be detected by T2 mapping as early as the second week and focused on the 7th, 11th, and 12th segments of left ventricle. The cutoff value of 46.64 for the 7th segment had the best diagnostic value, with an area under the curve (of 0.767, sensitivity of 100%, and specificity of 52%. T2* mapping could detect the change in iron content for early AIC at the middle interventricular septum and AILI as early as the sixth week (p = 0.014, p = 0.027). The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver (r = 0.39, p = 0.002). CONCLUSION: T2 and T2* mapping showed value one-stop assessment of AIC and AILI and could obtain the earliest MRI diagnosis point and optimal parameter thresholds for these conditions. CLINICAL RELEVANCE STATEMENT: Anthracycline-induced cardiotoxicity could be detected by T2 mapping as earlier as the second week, mainly focusing on the 7th, 11th, and 12th segments of left ventricle. Combined with T2* mapping, hepatoxicity and supplementary cardiotoxicity were assessed by one-stop scan. KEY POINTS: • MRI screening time of cardiotoxicity was as early as the second week with focusing on T2 values of the 7th, 11th, and 12th segments of left ventricle. • T2* mapping could be used as a complement to T2 mapping to evaluate cardiotoxicity and as an effective index to detect iron change in the early stages of chemotherapy. • The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver, indicating that iron content in the liver and heart increased with an increase in the chemotherapeutic drugs.


Asunto(s)
Antraciclinas , Antibióticos Antineoplásicos , Cardiotoxicidad , Doxorrubicina , Animales , Conejos , Antraciclinas/efectos adversos , Antibióticos Antineoplásicos/efectos adversos , Cardiotoxicidad/diagnóstico por imagen , Cardiotoxicidad/tratamiento farmacológico , Hierro , Hígado/diagnóstico por imagen , Doxorrubicina/uso terapéutico
13.
Inorg Chem ; 63(23): 10511-10518, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38768636

RESUMEN

Selective actinide coordination (from lanthanides) is critical for both nuclear waste management and sustainable development of nuclear power. Hydrophilic ligands used as masking agents to withhold actinides in the aqueous phase are currently highly pursued, while synthetic accessibility, water solubility, acid resistance, and extraction capability are the remaining problems. Most reported hydrophilic ligands are only effective at low acidity. We recently proved that the phenanthroline diimide skeleton was an efficient building block for the construction of highly efficient acid-resistant hydrophilic lanthanide/actinide separation agents, while the limited water solubility hindered the loading capability of the ligand. Herein, amine was introduced as the terminal solubilizing group onto the phenanthroline diimide backbone, which after protonation in acid showed high water solubility. The positively charged terminal amines enhanced the ligand water solubility to a large extent, which, on the other side, was believed to be detrimental for the coordination and complexation of the metal cations. We showed that by delicately adjusting the alkyl chain spacing, this intuitive disadvantage could be relieved and superior extraction performances could be achieved. This work holds significance for both hydrophilic lanthanide/actinide separation ligand design and, concurrently, offers insights into the development of water-soluble lanthanide/actinide complexes for biomedical and bioimaging applications.

14.
Nanotechnology ; 2024 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-39494696

RESUMEN

Manipulation of the electronic properties of layered transition-metal dichalcogenides (TMDs) is of fundamental significance for a wide range of electronic and optoelectronic applications. Surface charge transfer doping is considered to be a powerful technique to regulate the carrier density of TMDs. Herein, the controllable p-type surface modification of few-layer WSe2 by FeCl3 Lewis acid with different doping concentrations have been achieved. Effective hole doping of WSe2 has been demonstrated using Raman spectra and XPS. Transport properties indicated the p-type FeCl3 surface functionalization significantly increased the hole concentration with 1.2×1013 cm-2, resulting in 6 orders of magnitude improvement for the conductance of FeCl3-modified WSe2 compared with pristine WSe2. This work provides a promising approach and facilitate the further advancement of TMDs in electronic and optoelectronic applications. .

15.
Methods ; 220: 134-141, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37967757

RESUMEN

Automated 12-lead electrocardiographic (ECG) classification algorithms play an important role in the diagnosis of clinical arrhythmias. Current methods that perform well in the field of automatic ECG classification are usually based on Convolutional Neural Networks (CNN) or Transformer. However, due to the intrinsic locality of convolution operations, CNN can't extract long-dependence between series. On the other side, the Transformer design includes a built-in global self-attention mechanism, but it doesn't pay enough attention to local features. In this paper, we propose DAMS-Net, which combines the advantages of Transformer and CNN, introducing a spatial attention module and a channel attention module using a CNN-Transformer hybrid encoder to adaptively focus on the significant features of global and local parts between space and channels. In addition, our proposal fuses multi-scale information to capture high and low-level semantic information by skip-connections. We evaluate our method on the 2018 Physiological Electrical Signaling Challenge dataset, and our proposal achieves a precision rate of 83.6%, a recall rate of 84.7%, and an F1-score of 0.839. The classification performance is superior to all current single-model methods evaluated in this dataset. The experimental results demonstrate the promising application of our proposed method in 12-lead ECG automatic classification tasks.


Asunto(s)
Algoritmos , Electrocardiografía , Redes Neurales de la Computación , Semántica , Transducción de Señal , Procesamiento de Imagen Asistido por Computador
16.
J Biochem Mol Toxicol ; 38(1): e23523, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37654027

RESUMEN

Pyroptosis, a newly discovered pro-inflammatory programmed necrosis of cells, serves as an initiating and promoting event that leads to intervertebral disc (IVD) degeneration (IDD). Endoplasmic reticulum stress (ERS) and autophagy are vital regulatory mechanisms of cellular homeostasis, which is also closely related to IDD. However, the role and relationship of ERS and autophagy in the pyroptosis of nucleus pulposus cell (NPC) are not well understood. In this research, we aimed to elucidate the role and mechanism of ERS-C/EBP homologous protein (CHOP) in lipopolysaccharide (LPS)-induced cell pyroptosis and determine its interaction with autophagy. ERS and autophagy inducers or inhibitors were used or not in the preconditioning of rat NPCs. Cell viability, pyroptosis-related protein expression, caspase-1 activity assay, and enzyme-linked immunosorbent assay were performed to observe rat NPC pyroptosis after the treatment of LPS. Activation of the ERS pathway and autophagy were assessed by quantitative real-time PCR, western blot analyses, and immunofluorescence staining assay to classify the molecular mechanisms. Our results showed that LPS stimulation induced NPC pyroptosis with concomitant activation of the ERS-CHOP pathway and initiated autophagy. Activation of the ERS-CHOP pathway exacerbated rat NPC pyroptosis, whereas autophagy inhibited cell pyroptosis. LPS-induced cell pyroptosis and CHOP upregulation were negatively regulated by autophagy. LPS-induced autophagy was depressed by the ERS inhibitor but aggravated by the ERS inducer. Taken together, our findings suggested that LPS induced NPC pyroptosis by activating ERS-CHOP signaling and ERS mediated LPS-induced autophagy, which in turn alleviated NPC pyroptosis by inhibiting CHOP signaling.


Asunto(s)
Degeneración del Disco Intervertebral , Núcleo Pulposo , Ratas , Animales , Lipopolisacáridos/toxicidad , Núcleo Pulposo/metabolismo , Piroptosis , Estrés del Retículo Endoplásmico , Degeneración del Disco Intervertebral/metabolismo , Apoptosis/fisiología , Autofagia
17.
Neurol Sci ; 45(3): 873-881, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37945931

RESUMEN

Parkinson's disease (PD) is a gradual neurodegenerative disease. While drug therapy and surgical treatments have been the primary means of addressing PD, they do not offer a cure, and the risks associated with surgical treatment are high. Recent advances in cell reprogramming have given rise to new prospects for the treatment of Parkinson's disease (PD), with induced pluripotent stem cells (iPSCs), induced dopamine neurons (iDNs), and induced neural stem cells (iNSCs) being created. These cells can potentially be used in the treatment of Parkinson's disease. On the other hand, this article emphasizes the limits of iPSCs and iNSCs in the context of Parkinson's disease treatment, as well as approaches for direct reprogramming of somatic cells into iDNs. The paper will examine the benefits and drawbacks of directly converting somatic cells into iDNs.


Asunto(s)
Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Humanos , Neuronas Dopaminérgicas/fisiología , Enfermedad de Parkinson/terapia , Diferenciación Celular , Células Madre Pluripotentes Inducidas/fisiología
18.
Metab Brain Dis ; 39(5): 941-952, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38801506

RESUMEN

Diabetic cognitive impairment is a common complication in type 2 diabetes. Berberine (BBR) is an isoquinoline alkaloid that has been shown to have neuroprotective effects against diabetes. This study aimed to investigate the effect of BBR on the gray and white matter of the brain by using magnetic resonance imaging (MRI) and to explore the underlying mechanisms. The study used diabetic db/db mice and administered BBR (50 and 100 mg/kg) intragastrically for twelve weeks. Morris water maze was applied to examine cognitive function. T2-weighted imaging (T2WI) was performed to assess brain atrophy, and diffusion tensor imaging (DTI) combined with fiber tracking was conducted to monitor the structural integrity of the white matter, followed by histological immunostaining. Furthermore, the protein expressions of the phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (AKT)/ glycogen synthase kinase-3ß (GSK-3ß) were detected. The results revealed that BBR significantly improved the spatial learning and memory of the db/db mice. T2WI exhibited ameliorated brain atrophy in the BBR-treated db/db mice, as evidenced by reduced ventricular volume accompanied by increased hippocampal volumes. DTI combined with fiber tracking revealed that BBR increased FA, fiber density and length in the corpus callosum/external capsule of the db/db mice. These imaging findings were confirmed by histological immunostaining. Notably, BBR significantly enhanced the protein levels of phosphorylated AKT at Ser473 and GSK-3ß at Ser9. Collectively, this study demonstrated that BBR significantly improved the cognitive function of the diabetic db/db mice through ameliorating brain atrophy and promoting white matter reorganization via AKT/GSK-3ß pathway.


Asunto(s)
Atrofia , Berberina , Encéfalo , Disfunción Cognitiva , Imagen por Resonancia Magnética , Sustancia Blanca , Animales , Berberina/farmacología , Berberina/uso terapéutico , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/diagnóstico por imagen , Atrofia/tratamiento farmacológico , Ratones , Masculino , Sustancia Blanca/efectos de los fármacos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Sustancia Blanca/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt/metabolismo , Imagen de Difusión Tensora , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Glucógeno Sintasa Quinasa 3 beta/metabolismo
19.
Chem Biodivers ; : e202401539, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39344790

RESUMEN

Cornus officinalis total glycosides (COTG) derived from the traditional Chinese medicine Cornus officinalis, is a natural immunosuppressant and has been extensively studied in immunomodulation and immunosuppression. This study aimed to explore the effects of COTG on granulomatous lobular mastitis (GLM) and its associated mechanisms. Compared to the model group, COTG effectively ameliorated histopathological damage to breast tissue, reduced mammary gland suppuration, and enhanced the blood-milk barrier. Additionally, COTG treatment reduced the total number of T cells and B cells in GLM rats, significantly improving clinical indicators such as P-selectin, E-selectin, and intercellular cell adhesion molecule-1. We also observed downregulation of CD28 and B7 expression levels, an upregulation of cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) expression, and a significant decrease in inflammatory marker levels in the COTG group. COTG exerts an anti-inflammatory effect in GLM by stimulating CTLA-4, inhibiting the B7-CD28 signaling pathway affecting T cell activation, and promoting the blood-milk barrier. These findings suggest that COTG could be a promising therapeutic option for managing GLM, potentially improving patient outcomes by modulating immune responses and reinforcing the blood-milk barrier.

20.
Sensors (Basel) ; 24(16)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39204981

RESUMEN

For the purpose of improving performance and reducing the fabrication difficulty of terahertz traveling wave tubes (TWTs), this paper proposes a novel single-section high-gain slow wave structure (SWS), which is named the symmetrical quasi-synchronous step-transition (SQSST) folded waveguide (FW). The SQSST-FW SWS has an artificially designed quasi-synchronous region (QSR) to suppress self-oscillations for sustaining a high gain in an untruncated circuit. Simultaneously, a symmetrical design can improve the efficiency performance to some extent. A prototype of the SQSST-FW SWS for 650 GHz TWTs is designed based on small-signal analysis and numerical simulation. The simulation results indicate that the maximum saturation gain of the designed 650 GHz SQSST-FW TWT is 39.1 dB in a 34.3 mm slow wave circuit, occurring at the 645 GHz point when a 25.4 kV 15 mA electron beam and a 0.43 mW sinusoidal input signal are applied. In addition, a maximum output power exceeding 4 W is observed at the 648 GHz point using the same beam with an increased input power of around 2.8 mW.

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