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1.
Mol Cell ; 84(9): 1711-1726.e11, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38569554

RESUMEN

N6-methyladenosine (m6A) is a crucial RNA modification that regulates diverse biological processes in human cells, but its co-transcriptional deposition and functions remain poorly understood. Here, we identified the RNA helicase DDX21 with a previously unrecognized role in directing m6A modification on nascent RNA for co-transcriptional regulation. DDX21 interacts with METTL3 for co-recruitment to chromatin through its recognition of R-loops, which can be formed co-transcriptionally as nascent transcripts hybridize onto the template DNA strand. Moreover, DDX21's helicase activity is needed for METTL3-mediated m6A deposition onto nascent RNA following recruitment. At transcription termination regions, this nexus of actions promotes XRN2-mediated termination of RNAPII transcription. Disruption of any of these steps, including the loss of DDX21, METTL3, or their enzymatic activities, leads to defective termination that can induce DNA damage. Therefore, we propose that the R-loop-DDX21-METTL3 nexus forges the missing link for co-transcriptional modification of m6A, coordinating transcription termination and genome stability.


Asunto(s)
Adenosina , Adenosina/análogos & derivados , ARN Helicasas DEAD-box , Exorribonucleasas , Inestabilidad Genómica , Metiltransferasas , Estructuras R-Loop , ARN Polimerasa II , Terminación de la Transcripción Genética , Humanos , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Metiltransferasas/metabolismo , Metiltransferasas/genética , Adenosina/metabolismo , Adenosina/genética , Exorribonucleasas/metabolismo , Exorribonucleasas/genética , ARN Polimerasa II/metabolismo , ARN Polimerasa II/genética , Células HEK293 , Cromatina/metabolismo , Cromatina/genética , Daño del ADN , Células HeLa , ARN/metabolismo , ARN/genética , Transcripción Genética , Metilación de ARN
2.
Development ; 150(20)2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-36975381

RESUMEN

Methionine is important for intestinal development and homeostasis in various organisms. However, the underlying mechanisms are poorly understood. Here, we demonstrate that the methionine adenosyltransferase gene Mat2a is essential for intestinal development and that the metabolite S-adenosyl-L-methionine (SAM) plays an important role in intestinal homeostasis. Intestinal epithelial cell (IEC)-specific knockout of Mat2a exhibits impaired intestinal development and neonatal lethality. Mat2a deletion in the adult intestine reduces cell proliferation and triggers IEC apoptosis, leading to severe intestinal epithelial atrophy and intestinal inflammation. Mechanistically, we reveal that SAM maintains the integrity of differentiated epithelium and protects IECs from apoptosis by suppressing the expression of caspases 3 and 8 and their activation. SAM supplementation improves the defective intestinal epithelium and reduces inflammatory infiltration sequentially. In conclusion, our study demonstrates that methionine metabolism and its intermediate metabolite SAM play essential roles in intestinal development and homeostasis in mice.


Asunto(s)
Metionina Adenosiltransferasa , S-Adenosilmetionina , Ratones , Animales , S-Adenosilmetionina/metabolismo , Metionina Adenosiltransferasa/genética , Metionina Adenosiltransferasa/metabolismo , Mucosa Intestinal/metabolismo , Metionina , Suplementos Dietéticos
3.
Nature ; 581(7809): 401-405, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32461649

RESUMEN

Plasmonics enables the manipulation of light beyond the optical diffraction limit1-4 and may therefore confer advantages in applications such as photonic devices5-7, optical cloaking8,9, biochemical sensing10,11 and super-resolution imaging12,13. However, the essential field-confinement capability of plasmonic devices is always accompanied by a parasitic Ohmic loss, which severely reduces their performance. Therefore, plasmonic materials (those with collective oscillations of electrons) with a lower loss than noble metals have long been sought14-16. Here we present stable sodium-based plasmonic devices with state-of-the-art performance at near-infrared wavelengths. We fabricated high-quality sodium films with electron relaxation times as long as 0.42 picoseconds using a thermo-assisted spin-coating process. A direct-waveguide experiment shows that the propagation length of surface plasmon polaritons supported at the sodium-quartz interface can reach 200 micrometres at near-infrared wavelengths. We further demonstrate a room-temperature sodium-based plasmonic nanolaser with a lasing threshold of 140 kilowatts per square centimetre, lower than values previously reported for plasmonic nanolasers at near-infrared wavelengths. These sodium-based plasmonic devices show stable performance under ambient conditions over a period of several months after packaging with epoxy. These results indicate that the performance of plasmonic devices can be greatly improved beyond that of devices using noble metals, with implications for applications in plasmonics, nanophotonics and metamaterials.

4.
Nucleic Acids Res ; 51(D1): D39-D45, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36268869

RESUMEN

Transcription factors (TFs) are proteins that interact with specific DNA sequences to regulate gene expression and play crucial roles in all kinds of biological processes. To keep up with new data and provide a more comprehensive resource for TF research, we updated the Animal Transcription Factor Database (AnimalTFDB) to version 4.0 (http://bioinfo.life.hust.edu.cn/AnimalTFDB4/) with up-to-date data and functions. We refined the TF family rules and prediction pipeline to predict TFs in genome-wide protein sequences from Ensembl. As a result, we predicted 274 633 TF genes and 150 726 transcription cofactor genes in AnimalTFDB 4.0 in 183 animal genomes, which are 86 more species than AnimalTFDB 3.0. Besides double data volume, we also added the following new annotations and functions to the database: (i) variations (including mutations) on TF genes in various human cancers and other diseases; (ii) predicted post-translational modification sites (including phosphorylation, acetylation, methylation and ubiquitination sites) on TFs in 8 species; (iii) TF regulation in autophagy; (iv) comprehensive TF expression annotation for 38 species; (v) exact and batch search functions allow users to search AnimalTFDB flexibly. AnimalTFDB 4.0 is a useful resource for studying TF and transcription regulation, which contains comprehensive annotation and classification of TFs and transcription cofactors.


Asunto(s)
Bases de Datos Genéticas , Regulación de la Expresión Génica , Factores de Transcripción , Animales , Humanos , Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Factores de Transcripción/metabolismo
5.
Cardiovasc Diabetol ; 23(1): 283, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39097703

RESUMEN

BACKGROUND: Heart failure (HF) with improved ejection fraction (EF, HFimpEF) is a distinct HF subtype, characterized by left ventricular (LV) reverse remodeling and myocardial functional recovery. Multiple cardiometabolic factors are implicated in this process. Epicardial adipose tissue (EAT), emerging as an endocrine and paracrine organ, contributes to the onset and progression of HF. However, the relation between EAT and the incidence of HFimpEF is still unclear. METHODS: A total of 203 hospitalized HF patients with reduced EF (HFrEF, LVEF ≤ 40%) who underwent coronary CT angiography (CCTA) during index hospitalization were consecutively enrolled between November 2011 and December 2022. Routine follow-up and repeat echocardiograms were performed. The incidence of HFimpEF was defined as (1) an absolute LVEF improvement ≥ 10% and (2) a second LVEF > 40% (at least 3 months apart). EAT volume and density were semiautomatically quantified on non-enhanced series of CCTA scans. RESULTS: During a median follow-up of 8.6 (4.9 ~ 13.3) months, 104 (51.2%) patients developed HFimpEF. Compared with HFrEF patients, HFimpEF patients had lower EAT volume (115.36 [IQR 87.08 ~ 154.78] mL vs. 169.67 [IQR 137.22 ~ 218.89] mL, P < 0.001) and higher EAT density (-74.92 ± 6.84 HU vs. -78.76 ± 6.28 HU, P < 0.001). Multivariate analysis showed lower EAT volume (OR: 0.885 [95%CI 0.822 ~ 0.947]) and higher density (OR: 1.845 [95%CI 1.023 ~ 3.437]) were both independently associated with the incidence of HFimpEF. Subgroup analysis revealed that the association between EAT properties and HFimpEF was not modified by HF etiology. CONCLUSIONS: This study reveals that lower EAT volume and higher EAT density are associated with development of HFimpEF. Therapies targeted at reducing EAT quantity and improving its quality might provide favorable effects on myocardial recovery in HF patients.


Asunto(s)
Adiposidad , Angiografía por Tomografía Computarizada , Tejido Adiposo Epicárdico , Insuficiencia Cardíaca , Pericardio , Recuperación de la Función , Volumen Sistólico , Función Ventricular Izquierda , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Angiografía Coronaria , Tejido Adiposo Epicárdico/diagnóstico por imagen , Tejido Adiposo Epicárdico/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/diagnóstico por imagen , Pericardio/diagnóstico por imagen , Pericardio/fisiopatología , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Remodelación Ventricular
6.
FASEB J ; 37(2): e22743, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36645109

RESUMEN

Thrombospondin-2 (Tsp2), a glycoprotein in the extracellular matrix, plays a critical role in the maintenance of vascular homeostasis. However, its role in the pathogenesis of cardiovascular disorders such as intimal hyperplasia is not fully elucidated. This study, therefore, aims to explore the effect of Tsp2 on intimal hyperplasia and its associated underlying mechanisms. Intimal hyperplasia (IH) was established using a modified wire-mediated femoral artery injury model. Immunofluorescence and qPCR identified upregulated Tsp2 expression in the injured femoral artery compared with the uninjured femoral artery. Similarly, TSP2 expression was also increased in human samples from the atherosclerotic femoral artery and colocalized with vascular smooth muscle cells (VSMCs). Compared with the wild-type littermates, Tsp2 knockout mice displayed a mitigated IH in the injured femoral artery, as demonstrated by a decreased neointimal area and intimal/median ratio. Primary mouse VSMCs were cultured to explore the mechanism by which Tsp2 influenced IH in vitro. PDGF-stimulated VSMCs presented an elevated Tsp2 expression and enhanced migration and proliferation. However, Tsp2 knockdown by siRNA blocked the increased migration and proliferation of VSMCs. Further analysis identified an association between Notch3 and IH when the intracellular domain of Notch3 (Nicd3) was upregulated in PDGF-stimulated VSMCs and femoral arteries with IH in human tissues. Along with the overexpression and downregulation of Tsp2, the Nicd3 expression was also up and downregulated accordingly. Tsp2 was associated with IH and may serve as a therapeutic target for IH. Downregulation of Tsp2 could mitigate the progression of IH by modulating the proliferation and migration of VSMCs.


Asunto(s)
Músculo Liso Vascular , Neointima , Trombospondinas , Animales , Humanos , Ratones , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Hiperplasia/metabolismo , Ratones Noqueados , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Neointima/metabolismo , Trombospondinas/genética , Trombospondinas/metabolismo
7.
Analyst ; 149(2): 395-402, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38051224

RESUMEN

A europium-functionalized, dual-emissive, metal-organic framework-based fluorescence sensor (EuUCNDA) was constructed via post-synthetic modification of an UiO-66-type precursor through coordination interactions. EuUCNDA exhibited extremely high selectivity and sensitivity for malachite green (MG) with a low detection limit of 13.01 nM, a wide linear concentration range (0.05-50 µM), excellent anti-interference properties, a rapid response (<1 min), and the possibility of recycling. The good sensing performance of EuUCNDA enables the practical detection of MG in fish pond water and grass carp with good recoveries. Moreover, EuUCNDA can be reused for sensing MG and over 90% of fluorescence intensity can be restored after 7 cycles. Furthermore, EuUCNDA-embedded paper-based sensors combined with smartphone imaging afford portable and visual monitoring of MG in real samples. Notably, besides good sensing performance, EuUCNDA could efficiently remove MG from water. Hence, this work provides a recyclable and sensitive fluorescence sensor for portable, visual, rapid detection and efficient removal of MG.

8.
Acta Pharmacol Sin ; 45(1): 180-192, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37644132

RESUMEN

Adhesion molecules play essential roles in the homeostatic regulation and malignant transformation of hematopoietic cells. The dysregulated expression of adhesion molecules in leukemic cells accelerates disease progression and the development of drug resistance. Thus, targeting adhesion molecules represents an attractive anti-leukemic therapeutic strategy. In this study, we investigated the prognostic role and functional significance of cytohesin-1 (CYTH1) in acute myeloid leukemia (AML). Analysis of AML patient data from the GEPIA and BloodSpot databases revealed that CYTH1 was significantly overexpressed in AML and independently correlated with prognosis. Functional assays using AML cell lines and an AML xenograft mouse model confirmed that CYTH1 depletion significantly inhibited the adhesion, migration, homing, and engraftment of leukemic cells, delaying disease progression and prolonging animal survival. The CYTH1 inhibitor SecinH3 exerted in vitro and in vivo anti-leukemic effects by disrupting leukemic adhesion and survival programs. In line with the CYTH1 knockdown results, targeting CYTH1 by SecinH3 suppressed integrin-associated adhesion signaling by reducing ITGB2 expression. SecinH3 treatment efficiently induced the apoptosis and inhibited the growth of a panel of AML cell lines (MOLM-13, MV4-11 and THP-1) with mixed-lineage leukemia gene rearrangement, partly by reducing the expression of the anti-apoptotic protein MCL1. Moreover, we showed that SecinH3 synergized with the BCL2-selective inhibitor ABT-199 (venetoclax) to inhibit the proliferation and promote the apoptosis of ABT-199-resistant leukemic cells. Taken together, our results not only shed light on the role of CYTH1 in cell-adhesion-mediated leukemogenesis but also propose a novel combination treatment strategy for AML.


Asunto(s)
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Ratones , Animales , Leucemia Mieloide Aguda/tratamiento farmacológico , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Moléculas de Adhesión Celular , Progresión de la Enfermedad , Línea Celular Tumoral
9.
J Med Internet Res ; 26: e54876, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39094114

RESUMEN

BACKGROUND: The integration of telehealth-supported programs in chronic disease management has become increasingly common. However, its effectiveness for individuals with knee osteoarthritis (KOA) remains unclear. OBJECTIVE: This study aimed to assess the effectiveness of telehealth-supported exercise or physical activity programs for individuals with KOA. METHODS: A comprehensive literature search encompassing Embase, MEDLINE, CENTRAL, Web of Science, PubMed, Scopus, PEDro, GreyNet, and medRxiv from inception to September 2023 was conducted to identify randomized controlled trials comparing telehealth-supported exercise or physical activity programs to a control condition for KOA. Data were extracted and qualitatively synthesized across eligible studies, and a meta-analysis was performed to evaluate the effects. The study was reported according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020. RESULTS: In total, 23 studies met eligibility criteria, with 20 included in the meta-analysis. Results showed that telehealth-supported exercise or physical activity programs reduced pain (g=-0.39; 95% CI -0.67 to -0.11; P<.001), improved physical activity (g=0.13; 95% CI 0.03-0.23; P=.01), and enhanced physical function (g=-0.51; 95% CI -0.98 to -0.05; P=.03). Moreover, significant improvements in quality of life (g=0.25; 95% CI 0.14-0.36; P<.001), self-efficacy for pain (g=0.72; 95% CI 0.53-0.91; P<.001), and global improvement (odds ratio 2.69, 95% CI 1.41-5.15; P<.001) were observed. However, self-efficacy for physical function (g=0.14; 95% CI -0.26 to 0.53; P=.50) showed insignificant improvements. Subgroup analyses based on the World Health Organization classification of digital health (pain: χ22=6.5; P=.04 and physical function: χ22=6.4; P=.04), the type of teletechnology in the intervention group (pain: χ24=4.8; P=.31 and function: χ24=13.0; P=.01), and active or inactive controls (pain: χ21=5.3; P=.02 and physical function: χ21=3.4; P=.07) showed significant subgroup differences. CONCLUSIONS: Telehealth-supported exercise or physical activity programs might reduce knee pain and improve physical activity, physical function, quality of life, self-efficacy, and global improvement in individuals with KOA. Future research should consider longer implementation durations and assess the feasibility of incorporating wearables and standardized components into large-scale interventions to evaluate the effects. TRIAL REGISTRATION: PROSPERO CRD42022359658; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=359658.


Asunto(s)
Terapia por Ejercicio , Ejercicio Físico , Osteoartritis de la Rodilla , Telemedicina , Humanos , Osteoartritis de la Rodilla/rehabilitación , Osteoartritis de la Rodilla/terapia , Terapia por Ejercicio/métodos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Femenino , Masculino , Persona de Mediana Edad
10.
Chem Biodivers ; 21(2): e202301655, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38084071

RESUMEN

Six novel withanolides, along with nine known related compounds were isolated from the leaves of Datura stramonium L. The structures and absolute configurations of the new withanolides were elucidated by employing various spectral techniques and comparing them with those previously reported in the literature. In addition, four withanlides demonstrated interesting cytotoxic activity on LN229 cells with IC50 <20 µM.


Asunto(s)
Antineoplásicos , Datura stramonium , Witanólidos , Witanólidos/farmacología , Witanólidos/química , Estructura Molecular , Hojas de la Planta/química
11.
J Craniofac Surg ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264184

RESUMEN

OBJECTIVE: The authors compared the effect of 2 insertion methods, namely the conventional laryngeal mask airway (LMA) insertion and the index finger-assisted LMA insertion, on the incidence of complications associated with LMA Protector insertion. METHODS: The authors enrolled 300 patients, who underwent painless bronchoscopy. The patients ranged in age between 18 and 75 and were classified as American Society of Anesthesiologists grade I to III. They were randomly divided into 2 groups: a control group of 150 patients and an assisted group comprising 150 patients. LMA was inserted using the conventional and index finger-assisted insertion methods in both groups, respectively. The primary outcome was postoperative complications, such as oral mucosal injury and pharyngeal pain. Secondary outcomes included the success rate of first-time insertion, the incidence rate of inverse folding of LMA tips, oropharyngeal leak pressure (OLP), and other postoperative complications. RESULTS: Compared with the conventional LMA insertion method, index finger-assisted LMA insertion can significantly reduce the incidence rate of oral mucosal injury and pharyngeal pain, with fewer insertion failures. There was a statistically significant difference between the 2 groups in the visual field grading before adjustment for LMA alignment (P<0.0001). The conventional insertion method increased the likelihood of inverse folding of LMA tips. When the conventional insertion method was utilized, there was a significant difference in airway pressure and tidal volume before and after alignment under a fiberoptic bronchoscope (P<0.0001), but no significant difference in visual field grading and respiratory mechanics-related indicators. CONCLUSIONS: Index finger-assisted insertion can significantly reduce the incidence rate of LMA Protector-related complications and inverse folding of LMA tips.

12.
J Asian Nat Prod Res ; 26(8): 1001-1008, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38607260

RESUMEN

Phytochemical investigation on the fruiting bodies of the medicinal fungus Ganoderma lingzhi led to the isolation of a new norsteroid, namely ganonorsterone A (1), together with one known steroid, cyathisterol (2). The structure and absolute configuration of compound 1 were assigned by extensive analysis of MS, NMR data, and quantum-chemical calculations including electronic circular dichroism (ECD) and calculated 13C NMR-DP4+ analysis. Bioassay results showed that compound 1 displayed moderate inhibition on NO production in RAW 264.7 macrophages.


Asunto(s)
Ganoderma , Óxido Nítrico , Ganoderma/química , Ratones , Células RAW 264.7 , Animales , Estructura Molecular , Óxido Nítrico/biosíntesis , Óxido Nítrico/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Cuerpos Fructíferos de los Hongos/química
13.
Aesthetic Plast Surg ; 48(12): 2231-2238, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38528128

RESUMEN

BACKGROUND:  Infraorbital filler injection is a commonly used minimally invasive cosmetic procedure on the face, which can cause vascular complications. OBJECTIVE:  In this study, we aimed to explore the anatomical structure of the infraorbital vasculature and to establish an accurate protocol for infraorbital filler injection. METHODS:  The vascular structure of the infraorbital region was evaluated in 84 hemifacial specimens using computed tomography. Four segments (P1-P4) and five sections (C1-C5) were considered. We recorded the number of identified arteries in each slice and at each location and the number of deep arteries. Furthermore, we also measured the infraorbital artery (IOA) distribution. RESULTS:  At P1-P4, the lowest number of arteries was detected in segment P4, with a 317/1727 (18.4%) and 65/338 (2.3%) probability of total and deep arterial identification, respectively. The probabilities of encountering an identified artery at the five designated locations (C1-C5) were 277/1727 (16%), 318/1727 (18.4%), 410/1727 (23.7%), 397/1727 (23%), and 325/1727 (18.8%), respectively. The probability of an IOA being identified at C2 was 68/84 (81%). CONCLUSION:  We described an effective filler injection technique in the infraorbital region to minimize the associated risks. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Rellenos Dérmicos , Órbita , Humanos , Femenino , Masculino , Rellenos Dérmicos/efectos adversos , Rellenos Dérmicos/administración & dosificación , Órbita/irrigación sanguínea , Técnicas Cosméticas/efectos adversos , Cadáver , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Anciano , Cara/irrigación sanguínea , Anciano de 80 o más Años
14.
J Environ Manage ; 355: 120504, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38447513

RESUMEN

Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.


Asunto(s)
Ecosistema , Suelo , Suelo/química , Amoníaco/química , Carbono , Oxidación-Reducción , Archaea , Nitrificación , Microbiología del Suelo
15.
Molecules ; 29(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38542919

RESUMEN

To improve the mess-specific activity of Co supported on zeolite catalysts in Fischer-Tropsch (FT) synthesis, the Co-MCM-22 catalyst was prepared by simply grinding the MCM-22 with nanosized Co3O4 prefabricated by the thermal decomposition of the Co(II)-glycine complex. It is found that this novel strategy is effective for improving the mess-specific activity of Co catalysts in FT synthesis compared to the impregnation method. Moreover, the ion exchange and calcination sequence of MCM-22 has a significant influence on the dispersion, particle size distribution, and reduction degree of Co. The Co-MCM-22 prepared by the physical grinding of prefabricated Co3O4 and H+-type MCM-22 without a further calcination process exhibits a moderate interaction between Co3O4 and MCM-22, which results in the higher reduction degree, higher dispersion, and higher mess-specific activity of Co. Thus, the newly developed method is more controllable and promising for the synthesis of metal-supported catalysts.

16.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2766-2775, 2024 May.
Artículo en Zh | MEDLINE | ID: mdl-38812177

RESUMEN

Panax ginseng is reputed to be capable of replenishing healthy Qi and bolstering physical strength, and P. notoginseng can resolve blood stasis and alleviate pain. P. ginseng and P. notoginseng are frequently employed to treat ischemic heart diseases caused by blockages in the heart vessels. Mitochondrial dysfunction often coexists with abnormal mitochondrial morphology, and mitochondrial plasticity and dynamics play key roles in cardiovascular diseases. In this study, primary neonatal rat cardiomyocytes were exposed to 4 hours of hypoxia(H) followed by 2 hours of reoxygenation(R). MitoTracker Deep Red and Hoechst 33342 were used to label mitochondria and nuclei, respectively. Fluorescence images were then acquired using ImageXpress Micro Confocal. Automated image processing and parameter extraction/calculation were carried out using ImagePro Plus. Subsequently, representative parameters were selected as indicators to assess alterations in mitochondrial morphology and function. The active compounds of P. ginseng and P. notoginseng were screened out and identified based on the UPLC-Triple-TOF-MS results and mitochondrial morphometric parameters. The findings demonstrated that RS-2, RS-4, SQ-1, and SQ-4 significantly increased the values of three key morphometric parameters, including mitochondrial length, branching, and area, which might contribute to rescuing morphological features of myocardial cells damaged by H/R injury. Among the active components of the two medicinal herbs, 20(R)-ginsenoside Rg_3, ginsenoside Re, and gypenoside ⅩⅦ exhibited the strongest protective effects on mitochondria in cardiomyocytes. Specifically, 20(R)-ginsenoside Rg_3 might upregulate expression of optic atrophy 1(OPA1) and mitofusin 2(MFN2), and ginsenoside Re and gypenoside ⅩⅦ might selectively upregulate OPA1 expression. Collectively, they promoted mitochondrial membrane fusion and mitigated mitochondrial damage, thereby exerting protective effects on cardiomyocytes. This study provides experimental support for the discovery of novel therapeutic agents for myocardial ischemia-reperfusion injury from P. ginseng and P. notoginseng and offers a novel approach for large-scale screening of bioactive compounds with cardioprotective effects from traditional Chinese medicines.


Asunto(s)
Cardiotónicos , Medicamentos Herbarios Chinos , Miocitos Cardíacos , Panax notoginseng , Panax , Ratas Sprague-Dawley , Animales , Ratas , Panax/química , Panax notoginseng/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Cardiotónicos/farmacología , Cromatografía Líquida de Alta Presión , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Espectrometría de Masas
17.
Zhongguo Zhong Yao Za Zhi ; 49(1): 197-207, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38403352

RESUMEN

This study aims to reveal the mechanism of prenatal stress in affecting the testicular development of offspring rats and the intervention effects of Zuogui Pills via connexin 43(Cx43). Forty pregnant SD rats were randomized into a blank control group, a mo-del group, a high-dose(18.9 g·kg~(-1)) Zuogui Pills group, a low-dose(9.45 g·kg~(-1)) Zuogui Pills group, and a vitamin E(1.44 mg·kg~(-1)) group. The other groups except the blank control group was subjected to chronic unpredictable mild stress for the modeling of prenatal stress. The model was evaluated by sucrose preference test, open field test, and enzyme-linked immunosorbent assay(ELISA) of the glucocorticoid level. ELISA was employed to measure the thyroxine 4(T4), testosterone(T), and follicle-stimulating hormone(FSH) levels to assess kidney deficiency. Hematoxylin-eosin(HE) staining was employed to evaluate the status of testicular germ cells. An automatic sperm analyzer was used to measure the sperm quality. Immunofluorescence double staining was employed to detect the expression of Cx43 and follicle-stimulating hormone receptor(FSHR) in the testes of offspring rats. The mRNA and protein levels of Cx43, FSHR, phosphatidylinositol 3-kinase(PI3K), and protein kinase B(Akt) were determined by real-time fluorescence quantitative polymerase chain reaction and Western blot, respectively. Prenatal stress induced testicular development disorders in offspring rats. The HE staining results showed that on the day of birth, the model group had reduced seminiferous tubules in the testes, elevated FSH level in the serum, and lowered Cx43 level in the testicular tissue. Male offspring rats of 60 days old had reduced testicular spermatogenic function, decreased sperm quality, elevated FSH level and lowered T level in the serum, and down-regulated protein and mRNA levels of Cx43, FSHR, PI3K, and Akt in the testicular tissue. Zuogui Pills alleviated the abnormal development and dysfunction of testicles in the offspring rats caused by prenatal stress. In summary, Zuogui Pills may weaken the effects of prenatal stress on testicular development and spermatogenic function of offspring rats by activating the PI3K/Akt pathway to regulate Cx43 expression in the testicular tissue.


Asunto(s)
Conexina 43 , Medicamentos Herbarios Chinos , Proteínas Proto-Oncogénicas c-akt , Ratas , Masculino , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Conexina 43/farmacología , Ratas Sprague-Dawley , Fosfatidilinositol 3-Quinasas/metabolismo , Semen/metabolismo , Testículo , Hormona Folículo Estimulante/metabolismo , Hormona Folículo Estimulante/farmacología , ARN Mensajero/metabolismo
18.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1717-1724, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38812184

RESUMEN

Panax ginseng, known as the "king of herbs", is a highly valued medicinal plant, and its medicinal parts include roots, stems, leaves, flowers, and fruits, among which the roots are the most commonly used. The main active components of this medicinal plant include triterpenoid saponins, polysaccharides, peptides, and volatile oils. The chemical components and active metabolites endow this herb with a variety of pharmacological effects, and thus this herb is used to treat various diseases and play healthcare roles. Currently, a wide range of preparations of P. ginseng have been officially registered and marketed, including tablets, oral liquids, and injections, which demonstrate good clinical efficacy in regulating immunity, adjuvant treatment of tumors, alleviating fatigue, delaying the aging process, improving glucose and lipid metabolism, treating cardiovascular diseases, and relieving inflammation and pain. The production process and quality standards of these drugs are of great significance to ensure their efficacy. According to the theory that Ginseng Radix et Rhizoma can greatly replenish original Qi, tonify the spleen and lung, promote fluid production to quench thirst, tranquilize mind and enrich the intelligence, this paper systematically summarized the clinical application progress of P. ginseng and rela-ted preparations on the market and prospected the further development of preparations from P. ginseng, providing a reference for further exploring the medicinal value and healthcare function of this herb. The above contents, as an important basis for the in-depth development of P. ginseng and related drugs, increase the possibilities for the application of P. ginseng.


Asunto(s)
Medicamentos Herbarios Chinos , Panax , Panax/química , Humanos , Medicamentos Herbarios Chinos/química , Animales
19.
Zhongguo Zhong Yao Za Zhi ; 49(11): 3002-3011, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-39041160

RESUMEN

This study aims to observe the effects of the traditional Chinese medicine prescription Dahuang Zhechong Pills(DHZCP on renal aging and explore its potential multi-target effects. Rats were assigned into the normal, model, DHZCP, and vitamin E(VE)groups. Firstly, the rat model of D-galactose(D-gal)-induced renal aging was established. During the modeling period, the rats in the 4 groups were administrated with double distilled water, double distilled water, DHZCP suspension, and VE suspension, respectively,by gavage every day. On day 60 of intervention, the indicators of renal aging and injury in rats were measured, including the function,histopathological characteristics, senescence-associated ß-galactosidase( SA-ß-gal) staining, and expression levels of Klotho and proteins associated with cell cycle arrest and senescence-associated secretory phenotype(SASP) in the renal tissue. Moreover, nontargeted metabolomic analysis of the renal tissue was performed for the 4 groups of rats to screen out the potential biomarkers and metabolic pathways. Finally, the signaling pathways of key targets were preliminarily validated. The results showed that DHZCP and VE significantly improved the renal function, histopathological features of renal tubular/interstitial tissue, and degree of SA-ß-gal staining, up-regulated the expression level of Klotho, and down-regulated the expression levels of proteins associated with cell cycle arrest and SASP in the renal tissue of the aging rats. In addition, DHZCP and VE regulated the metabolites in the renal tissue of the aging rats. There were 21 common differential metabolites. Among them, 5 differential metabolites were significantly increased in the aging rats and recovered after DHZCP or VE treatment, and they were involved in the lipid metabolism and energy metabolism pathways. The areas under the curves of the groups in comparison varied within the range of 0. 88-1. DHZCP regulated multiple signaling pathways, such as the adenosine monophosphate-activated protein kinase(AMPK), cyclic guanosine monophosphate-protein kinase G( c GMP-PKG), cyclic adenylic acid( c AMP), phosphatidylinositol-3-kinase-protein kinase B( PI3K-Akt), mammalian target of rapamycin(mTOR), and autophagy signaling pathways. In addition, it affected the multiple metabolic pathways, such as renin secretion, longevity regulation pathway, diabetic cardiomyopathy, and niacin and nicotinamide metabolism. DHZCP and VE significantly up-regulated the expression level of the key proteins in the AMPK signaling pathway in the renal tissue of the aging rats. In all, DHZCP and VE could mitigate renal aging and injury. DHZCP exerted multi-target effects via multiple signaling pathways and metabolic pathways in the kidney, in which the AMPK signaling pathway may be one of the key targets for action.


Asunto(s)
Envejecimiento , Medicamentos Herbarios Chinos , Riñón , Metabolómica , Ratas Sprague-Dawley , Animales , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Ratas , Riñón/efectos de los fármacos , Riñón/metabolismo , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Masculino , Transducción de Señal/efectos de los fármacos
20.
Angew Chem Int Ed Engl ; 63(13): e202400196, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38356038

RESUMEN

The development of new chemically recyclable polymers via monomer design would provide a transformative strategy to address the energy crisis and plastic pollution problem. Biaryl-fused cyclic esters were targeted to generate axially chiral polymers, which would impart new material performance. To overcome the non-polymerizability of the biaryl-fused monomer DBO, a cyclic ester Me-DBO installed with dimethyl substitution was prepared to enable its polymerizability via enhancing torsional strain. Impressively, Me-DBO readily went through well-controlled ring-opening polymerization, producing polymer P(Me-DBO) with high glass transition temperature (Tg >100 °C). Intriguingly, mixing these complementary enantiopure polymers containing axial chirality promoted a transformation from amorphous to crystalline material, affording a semicrystalline stereocomplex with a melting transition temperature more than 300 °C. P(Me-DBO) were capable of depolymerizing back to Me-DBO in high efficiency, highlighting an excellent recyclability.

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