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1.
Mol Cell ; 82(23): 4503-4518.e8, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36306795

RESUMEN

In the type III-E CRISPR-Cas system, a Cas effector (gRAMP) is associated with a TPR-CHAT to form Craspase (CRISPR-guided caspase). However, both the structural features of gRAMP and the immunity mechanism remain unknown for this system. Here, we report structures of gRAMP-crRNA and gRAMP:cRNA:target RNA as well as structures of Craspase and Craspase complexed with cognate target RNA (CTR) or non-cognate target RNA (NTR). Importantly, the 3' anti-tag region of NTR and CTR binds at two distinct channels in Craspase, and CTR with a non-complementary 3' anti-tag induces a marked conformational change of the TPR-CHAT, which allosterically activates its protease activity to cleave an ancillary protein Csx30. This cleavage then triggers an abortive infection as the antiviral strategy of the type III-E system. Together, our study provides crucial insights into both the catalytic mechanism of the gRAMP and the immunity mechanism of the type III-E system.


Asunto(s)
Proteínas Asociadas a CRISPR , Proteínas Asociadas a CRISPR/genética , ARN/metabolismo , Antivirales , Sistemas CRISPR-Cas , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo
2.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38171931

RESUMEN

The advancement of single-cell sequencing technology has smoothed the ability to do biological studies at the cellular level. Nevertheless, single-cell RNA sequencing (scRNA-seq) data presents several obstacles due to the considerable heterogeneity, sparsity and complexity. Although many machine-learning models have been devised to tackle these difficulties, there is still a need to enhance their efficiency and accuracy. Current deep learning methods often fail to fully exploit the intrinsic interconnections within cells, resulting in unsatisfactory results. Given these obstacles, we propose a unique approach for analyzing scRNA-seq data called scMPN. This methodology integrates multi-layer perceptron and graph neural network, including attention network, to execute gene imputation and cell clustering tasks. In order to evaluate the gene imputation performance of scMPN, several metrics like cosine similarity, median L1 distance and root mean square error are used. These metrics are utilized to compare the efficacy of scMPN with other existing approaches. This research utilizes criteria such as adjusted mutual information, normalized mutual information and integrity score to assess the efficacy of cell clustering across different approaches. The superiority of scMPN over current single-cell data processing techniques in cell clustering and gene imputation investigations is shown by the experimental findings obtained from four datasets with gold-standard cell labels. This observation demonstrates the efficacy of our suggested methodology in using deep learning methodologies to enhance the interpretation of scRNA-seq data.


Asunto(s)
Benchmarking , Análisis de Expresión Génica de una Sola Célula , Análisis por Conglomerados , Análisis de Datos , Redes Neurales de la Computación , Análisis de Secuencia de ARN , Perfilación de la Expresión Génica
3.
BMC Plant Biol ; 24(1): 590, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38902595

RESUMEN

BACKGROUND: The Prunus sibirica seeds with rich oils has great utilization, but contain amygdalin that can be hydrolyzed to release toxic HCN. Thus, how to effectively reduce seed amygdalin content of P. sibirica is an interesting question. Mandelonitrile is known as one key intermediate of amygdalin metabolism, but which mandelonitrile lyase (MDL) family member essential for its dissociation destined to low amygdalin accumulation in P. sibirica seeds still remains enigmatic. An integration of our recent 454 RNA-seq data, amygdalin and mandelonitrile content detection, qRT-PCR analysis and function determination is described as a critical attempt to determine key MDL and to highlight its function in governing mandelonitrile catabolism with low amygdalin accumulation in Prunus sibirica seeds for better developing edible oil and biodiesel in China. RESULTS: To identify key MDL and to unravel its function in governing seed mandelonitrile catabolism with low amygdalin accumulation in P. sibirica. Global identification of mandelonitrile catabolism-associated MDLs, integrated with the across-accessions/developing stages association of accumulative amount of amygdalin and mandelonitrile with transcriptional level of MDLs was performed on P. sibirica seeds of 5 accessions to determine crucial MDL2 for seed mandelonitrile catabolism of P. sibirica. MDL2 gene was cloned from the seeds of P. sibirica, and yeast eukaryotic expression revealed an ability of MDL2 to specifically catalyze the dissociation of mandelonitrile with the ideal values of Km (0.22 mM) and Vmax (178.57 U/mg). A combination of overexpression and mutation was conducted in Arabidopsis. Overexpression of PsMDL2 decreased seed mandelonitrile content with an increase of oil accumulation, upregulated transcript of mandelonitrile metabolic enzymes and oil synthesis enzymes (involving FA biosynthesis and TAG assembly), but exhibited an opposite situation in mdl2 mutant, revealing a role of PsMDL2-mediated regulation in seed amygdalin and oil biosynthesis. The PsMDL2 gene has shown as key molecular target for bioengineering high seed oil production with low amygdalin in oilseed plants. CONCLUSIONS: This work presents the first integrated assay of genome-wide identification of mandelonitrile catabolism-related MDLs and the comparative association of transcriptional level of MDLs with accumulative amount of amygdalin and mandelonitrile in the seeds across different germplasms and developmental periods of P. sibirica to determine MDL2 for mandelonitrile dissociation, and an effective combination of PsMDL2 expression and mutation, oil and mandelonitrile content detection and qRT-PCR assay was performed to unravel a mechanism of PsMDL2 for controlling amygdalin and oil production in P. sibirica seeds. These findings could offer new bioengineering strategy for high oil production with low amygdalin in oil plants.


Asunto(s)
Amigdalina , Prunus , Semillas , Amigdalina/metabolismo , Prunus/genética , Prunus/metabolismo , Prunus/enzimología , Semillas/metabolismo , Semillas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Aceites de Plantas/metabolismo , Aldehído-Liasas/metabolismo , Aldehído-Liasas/genética , Regulación de la Expresión Génica de las Plantas
4.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38931803

RESUMEN

The rapid advancement of blockchain technology has fueled the prosperity of the cryptocurrency market. Unfortunately, it has also facilitated certain criminal activities, particularly the increasing issue of phishing scams on blockchain platforms such as Ethereum. Consequently, developing an efficient phishing detection system is critical for ensuring the security and reliability of cryptocurrency transactions. However, existing methods have shortcomings in dealing with sample imbalance and effective feature extraction. To address these issues, this study proposes an Ethereum phishing scam detection method based on DA-HGNN (Data Augmentation Method and Hybrid Graph Neural Network Model), validated by real Ethereum datasets to prove its effectiveness. Initially, basic node features consisting of 11 attributes were designed. This study applied a sliding window sampling method based on node transactions for data augmentation. Since phishing nodes often initiate numerous transactions, the augmented samples tended to balance. Subsequently, the Temporal Features Extraction Module employed Conv1D (One-Dimensional Convolutional neural network) and GRU-MHA (GRU-Multi-Head Attention) models to uncover intrinsic relationships between features from the time sequences and to mine adequate local features, culminating in the extraction of temporal features. The GAE (Graph Autoencoder) concept was then leveraged, with SAGEConv (Graph SAGE Convolution) as the encoder. In the SAGEConv reconstruction module, by reconstructing the relationships between transaction graph nodes, the structural features of the nodes were learned, obtaining reconstructed node embedding representations. Ultimately, phishing fraud nodes were further identified by integrating temporal features, basic features, and embedding representations. A real Ethereum dataset was collected for evaluation, and the DA-HGNN model achieved an AUC-ROC (Area Under the Receiver Operating Characteristic Curve) of 0.994, a Recall of 0.995, and an F1-score of 0.994, outperforming existing methods and baseline models.

5.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474323

RESUMEN

This work aimed to identify the chemical compounds of Cinnamomum burmannii leaf essential oil (CBLEO) and to unravel the antibacterial mechanism of CBLEO at the molecular level for developing antimicrobials. CBLEO had 37 volatile compounds with abundant borneol (28.40%) and showed good potential to control foodborne pathogens, of which Staphylococcus aureus had the greatest inhibition zone diameter (28.72 mm) with the lowest values of minimum inhibitory concentration (1.0 µg/mL) and bactericidal concentration (2.0 µg/mL). To unravel the antibacterial action of CBLEO on S. aureus, a dynamic exploration of antibacterial growth, material leakage, ROS formation, protein oxidation, cell morphology, and interaction with genome DNA was conducted on S. aureus exposed to CBLEO at different doses (1/2-2×MIC) and times (0-24 h), indicating that CBLEO acts as an inducer for ROS production and the oxidative stress of S. aureus. To highlight the antibacterial action of CBLEO on S. aureus at the molecular level, we performed a comparative association of ROS accumulation with some key virulence-related gene (sigB/agrA/sarA/icaA/cidA/rsbU) transcription, protease production, and biofilm formation in S. aureus subjected to CBLEO at different levels and times, revealing that CBLEO-induced oxidative stress caused transcript suppression of virulence regulators (RsbU and SigB) and its targeted genes, causing a protease level increase destined for the biofilm formation and growth inhibition of S. aureus, which may be a key bactericidal action. Our findings provide valuable information for studying the antibacterial mechanism of essential oil against pathogens.


Asunto(s)
Cinnamomum , Aceites Volátiles , Aceites Volátiles/farmacología , Cinnamomum/genética , Staphylococcus aureus/fisiología , Virulencia , Especies Reactivas de Oxígeno , Antibacterianos/farmacología , Biopelículas , Estrés Oxidativo , Transcripción Genética , Péptido Hidrolasas/genética , Pruebas de Sensibilidad Microbiana
6.
Beilstein J Org Chem ; 20: 1436-1443, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952962

RESUMEN

An efficient protocol for the synthesis of polyfunctionalized tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine-3,4b,5,6,7(1H)-pentacarboxylates was developed by a three-component reaction. In the absence of any catalyst, the three-component reaction of alkyl isocyanides, dialkyl but-2-ynedioates and 5,6-unsubstituted 1,4-dihydropyridines in refluxing acetonitrile afforded polyfunctionalized tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine-3,4b,5,6,7(1H)-pentacarboxylates in high yields and with high diastereoselectivity. The reaction was finished by in situ generation of activated 5-(alkylimino)cyclopenta-1,3-dienes from addition of alkyl isocyanide to two molecules of but-2-ynedioates and sequential formal [3 + 2] cycloaddition reaction with 5,6-unsubstituted 1,4-dihydropyridine.

7.
BMC Plant Biol ; 23(1): 268, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37208597

RESUMEN

BACKGROUND: Based on our previous studied on different provenances of Pistacia chinensis, some accessions with high quality and quantity of seed oils has emerged as novel source of biodiesel. To better develop P. chinensis seed oils as woody biodiesel, a concurrent exploration of oil content, FA profile, biodiesel yield, and fuel properties was conducted on the seeds from 5 plus germplasms to determine superior genotype for ideal biodiesel production. Another vital challenge is to unravel mechanism that govern the differences in oil content and FA profile of P. chinensis seeds across different accessions. FA biosynthesis and oil accumulation of oil plants are known to be highly controlled by the transcription factors. An integrated analysis of our recent transcriptome data, qRT-PCR detection and functional identification was performed as an attempt to highlight LEC1/WRI1-mediated transcription regulatory mechanism for high-quality oil accumulation in P. chinensis seeds. RESULTS: To select ideal germplasm and unravel high oil accumulative mechanism for developing P. chinensis seed oils as biodiesel, five plus trees (accession PC-BJ/PC-AH/PC-SX/PC-HN/PC-HB) with high-yield seeds were selected to assess the variabilities in weight, oil content, FA profile, biodiesel yield and fuel property, revealing a variation in the levels of seed oil (50.76-60.88%), monounsaturated FA (42.80-70.72%) and polyunsaturated FA (18.78-43.35%), and biodiesel yield (84.98-98.15%) across different accessions. PC-HN had a maximum values of seed weight (26.23 mg), oil (60.88%) and biodiesel yield (98.15%), and ideal proportions of C18:1 (69.94%), C18:2 (17.65%) and C18:3 (1.13%), implying that seed oils of accession PC-HN was the most suitable for ideal biodiesel production. To highlight molecular mechanism that govern such differences in oil content and FA profile of different accessions, a combination of our recent transcriptome data, qRT-PCR detection and protein interaction analysis was performed to identify a pivotal role of LEC1/WRI1-mediated transcription regulatory network in high oil accumulation of P. chinensis seeds from different accessions. Notably, overexpression of PcWRI1 or PcLEC1 from P. chinensis seeds in Arabidopsis could facilitate seed development and upregulate several genes relevant for carbon flux allocation (plastidic glycolysis and acetyl-CoA generation), FA synthesis, TAG assembly and oil storage, causing an increase in seed oil content and monounsaturated FA level, destined for biodiesel fuel property improvement. Our findings may present strategies for better developing P. chinensis seed oils as biodiesel feedstock and bioengineering its high oil accumulation. CONCLUSIONS: This is the first report on the cross-accessions assessments of P. chinensis seed oils to determine ideal accession for high-quality biodiesel production, and an effective combination of PcWRI1 or PcLEC1 overexpression, morphological assay, oil accumulation and qRT-PCR detection was applied to unravel a role of LEC1/WRI1-mediated regulatory network for oil accumulation in P. chinensis seeds, and to highlight the potential application of PcWRI1 or PcLEC1 for increasing oil production. Our finding may provide new strategies for developing biodiesel resource and molecular breeding.


Asunto(s)
Biocombustibles , Pistacia , Aceites de Plantas , Arabidopsis/metabolismo , Ácidos Grasos/metabolismo , Pistacia/genética , Pistacia/metabolismo , Aceites de Plantas/metabolismo , Semillas
8.
BMC Med ; 21(1): 94, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36927541

RESUMEN

BACKGROUND: Previous studies have shown that monotherapy with apatinib, an oral tyrosine kinase inhibitor, has promising efficacy for treating recurrent or metastatic (RM) nasopharyngeal carcinoma (NPC) patients. In this study, we aimed to assess the efficacy and safety of apatinib combined with capecitabine as a second-line therapy or beyond for treating RM-NPC patients who failed the first-line platinum-based chemotherapy. METHODS: In this single-arm, phase II study, we enrolled RM-NPC patients who had at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST v1.1). The sample size was determined using Simon's two-stage design. All patients were administered with apatinib 500 mg once daily and capecitabine 1000 mg/m2 twice per day on days 1-14 of each 21-day cycle. The primary endpoint was the objective response rate (ORR), and the secondary endpoints comprised disease control rate (DCR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: We enrolled 64 patients from September 2018 to August 2020. The ORR and DCR were 39.1% (95% CI, 27.1-52.1) and 85.9% (95% CI, 75.0-93.4), respectively. The median DoR was 14.4 months (95% CI, 7.8-21.0). As of April 20, 2021, the median follow-up duration was 12.0 months. The median PFS was 7.5 months (95% CI, 5.0-10.0) and the median OS was 15.7 months (95% CI, 11.3-20.1). The most common toxicities of any grade were anemia (75.0%), hand-foot syndrome (65.6%), and proteinuria (64.0%). Grade 3-4 toxicities were observed in 36 (56.3%) patients, with hypertension (14.1%), mucositis (12.4%), and fatigue (10.9%) most commonly observed. CONCLUSIONS: Apatinib plus capecitabine shows promising efficacy as a second-line treatment option in pretreated platinum-refractory RM-NPC patients. Dose selection of this combination needs further investigation considering the toxicity. TRIAL REGISTRATION: Chi-CTR1800017229.


Asunto(s)
Neoplasias Nasofaríngeas , Humanos , Capecitabina/efectos adversos , Estudios Prospectivos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/tratamiento farmacológico
9.
Epilepsia ; 64(10): 2667-2678, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37522416

RESUMEN

OBJECTIVE: Bone metabolism can be influenced by a range of factors. We selected children with self-limited epilepsy with centrotemporal spikes (SeLECTS) and lifestyles similar to those of healthy children to control for the confounding factors that may influence bone metabolism. We aimed to identify the specific effects of epilepsy and/or anti-seizure medications (ASMs) on bone metabolism. METHODS: Patients with SeLECTS were divided into an untreated group and a monotherapy group, and the third group was a healthy control group. We determined the levels of various biochemical markers of bone metabolism, including procollagen type I nitrogenous propeptide (PINP), alkaline phosphatase (ALP), osteocalcin (OC), collagen type I cross-linked C-telopeptide (CTX), calcium, magnesium, phosphorus, parathyroid hormone (PTH), and vitamin D3 (VD3 ). RESULTS: A total of 1487 patients (from 19 centers) were diagnosed with SeLECTS; 1032 were analyzed, including 117 patients who did not receive any ASMs (untreated group), 643 patients who received only one ASM (monotherapy group), and 272 children in the healthy control group. Except for VD3 , other bone metabolism of the three groups were different (p < .001). Bone metabolism was significantly lower in the untreated group than the healthy control group (p < .05). There were significant differences between the monotherapy and healthy control group in the level of many markers. However, when comparing the monotherapy and untreated groups, the results were different; oxcarbazepine, levetiracetam, and topiramate had no significant effect on bone metabolism. Phosphorus and magnesium were significantly lower in the valproic acid group than the untreated group (adjusted p < .05, Cliff's delta .282-.768). CTX was significantly higher in the lamotrigine group than in the untreated group (adjusted p = .012, Cliff's delta = .316). SIGNIFICANCE: Epilepsy can affect many aspects of bone metabolism. After controlling epilepsy and other confounders that affect bone metabolism, we found that the effects of ASMs on bone metabolism differed. Oxcarbazepine, levetiracetam, and topiramate did not affect bone metabolism, and lamotrigine corrected some of the abnormal markers of bone metabolism in patients with epilepsy.

10.
Nucleic Acids Res ; 49(17): 10178-10191, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34432044

RESUMEN

CRISPR-Cas systems are bacterial adaptive immune systems, and phages counteract these systems using many approaches such as producing anti-CRISPR (Acr) proteins. Here, we report the structures of both AcrIF14 and its complex with the crRNA-guided surveillance (Csy) complex. Our study demonstrates that apart from interacting with the Csy complex to block the hybridization of target DNA to the crRNA, AcrIF14 also endows the Csy complex with the ability to interact with non-sequence-specific dsDNA as AcrIF9 does. Further structural studies of the Csy-AcrIF14-dsDNA complex and biochemical studies uncover that the PAM recognition loop of the Cas8f subunit of the Csy complex and electropositive patches within the N-terminal domain of AcrIF14 are essential for the non-sequence-specific dsDNA binding to the Csy-AcrIF14 complex, which is different from the mechanism of AcrIF9. Our findings highlight the prevalence of Acr-induced non-specific DNA binding and shed light on future studies into the mechanisms of such Acr proteins.


Asunto(s)
Sistemas CRISPR-Cas/genética , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Endodesoxirribonucleasas/metabolismo , Pseudomonas aeruginosa/genética , Bacteriófagos/genética , Bacteriófagos/crecimiento & desarrollo , Proteínas Asociadas a CRISPR/metabolismo , ADN/genética , Proteínas de Unión al ADN/antagonistas & inhibidores , Conformación Proteica , Pseudomonas aeruginosa/virología , Proteínas Virales/genética , Proteínas Virales/metabolismo
11.
Mikrochim Acta ; 190(6): 246, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37256373

RESUMEN

Two-dimensional metal-organic framework (MOF) composites were produced by incorporating Fe-MOFs into reduced graphene oxide (rGO) nanosheets to form Fe-MOF/rGO composites by hydrothermal synthesis. SEM, TEM, XRD, XPS, and measurements of contact angles were used to characterize the composites. TEM studies revealed that the rod-like-shaped Fe-MOFs were extensively dispersed on the rGO sheets. Incorporating Fe-MOF into rGO significantly improves performance due to the large surface area, chemical stability, and high electrical conductivity. The response signals for the electrochemical sensing performance of Fe-MOF/rGO-modified electrodes to nitrofurazone (NFZ) were significantly enhanced. Differential pulse voltammetry was used to detect the NFZ, and the MOF/rGO sensor possesses a lower detection limit (0.77µM) with two dynamic ranges from 0.6-60 to 128-499.3 µM and high sensitivity (1.909 µA·mM-1·cm-2). Moreover, the anti-interference properties of the sensor were quite reproducible and stable. To understand the mechanism responsible for the enhanced sensing performance of the composite, grand canonical Monte Carlo calculations were performed for Fe-MOF/rGO composites with five unit cells of Fe-MOF and four layers of rGO. We attributed the improvement to the fact that the interface between the Fe-MOF and rGO absorbed increased NFZ molecules. The findings reported herein confirm that such Fe-MOF/rGO composites have significantly improved electrochemical performance and practical applicability of sensing nitrofurazone.

12.
Molecules ; 28(4)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36838776

RESUMEN

In order to explore the mechanism responsible for the interactions in the surfactant-polymer composite flooding and broaden the application range of the binary system in heterogeneous oil reservoirs, in this paper, the influences of different surfactants on the viscosity of two polymers with similar molecular weights, partially hydrolyzed polyacrylamide (HPAM) and hydrophobically modified polyacrylamide (HMPAM), were studied at different reservoir environments. In addition, the relationship between the surfactant-polymer synergistic effects and oil displacement efficiency was also investigated. The experimental results show that for HPAM, surfactants mainly act as an electrolyte to reduce its viscosity. For HMPAM, SDBS and TX-100 will form aggregates with the hydrophobic blocks of polymer molecules, reducing the bulk viscosity. However, zwitterionic surfactant aralkyl substituted alkyl sulfobetaine BSB molecules can build "bridges" between different polymer molecules through hydrogen bonding and electrostatic interaction. After forming aggregates with HMPAM molecules, the viscosity will increase. The presence of two polymers all weakened the surfactant oil-water interfacial membrane strength to a certain extent, but had little effect on the interfacial tension. The synergistic effect of the "bridge" between HMPAM and BSB under macroscopic conditions also occurs in the microscopic pores of the core, which has a beneficial effect on improving oil recovery.


Asunto(s)
Polímeros , Tensoactivos , Tensoactivos/química , Polímeros/química , Resinas Acrílicas/química
13.
Molecules ; 28(3)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36770949

RESUMEN

Betaine is a new surfactant with good application prospects in high-temperature and high-salinity reservoirs. The interfacial properties of two kinds of betaine mixtures with a good synergistic effect were evaluated in this paper. On this basis, the effects of temperature-resistant, salt-resistant polymers with different contents of 2-acrylamide-2-methylpropanesulfonic acid (AMPS) on dynamic interfacial tensions (IFTs) against n-alkanes and crude oil were studied. The experimental results show that the IFTs between betaine ASB and n-alkanes can be reduced to ultra-low values by compounding with anionic surfactant petroleum sulfonate (PS) and extended anionic surfactant alkoxyethylene carboxylate (AEC), respectively. ASB@AEC is very oil-soluble with nmin value ≥14, and ASB@PS is relatively water-soluble with nmin value of 10. The water solubility of both ASB@PS and ASB@AEC is enhanced by the addition of water-soluble polymers. The HLB of the ASB@AEC solution becomes better against crude oil after the addition of polymers, and the IFT decreases to an ultra-low value as a result. On the contrary, the antagonistic effect in reducing the IFT can be observed for ASB@PS in the same case. In a word, polymers affect the IFTs of surfactant solutions by regulating the HLB.

14.
Zhongguo Zhong Yao Za Zhi ; 48(13): 3576-3588, 2023 Jul.
Artículo en Zh | MEDLINE | ID: mdl-37474991

RESUMEN

Network pharmacology, molecular docking, and in vivo and in vitro experiments were employed to study the molecular mechanism of Blaps rynchopetera Fairmaire in the treatment of non-small cell lung cancer(NSCLC). The components of B. rynchopetera were collected by literature review, and the active components were screened out through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). PharmMapper was used to obtain the targets of the active components. The targets of NSCLC were obtained from DrugBank, GeneCards, OMIM, TTD, and PharmGKB. The Venn diagram was drawn to identify the common targets shared by the active components of B. rynchopetera and NSCLC. The "drug component-target" network and protein-protein interaction(PPI) network were constructed by Cytoscape, and the key targets were screened by Centiscape. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the above key targets were performed by DAVID. AutoDock and PyMOL were used for the molecular docking between the key targets and corresponding active components. A total of 31 active components, 72 potential targets, and 11 key targets of B. rynchopetera against NSCLC were obtained. The active components of B. rynchopetera had good binding activity with key targets. Further, the serum containing B. rynchopetera was prepared and used to culture human lung adenocarcinoma A549 cells. The CCK-8 assay was employed to determine the inhibition rates on the growth of A549 cells in blank control group and those exposed to different concentrations of B. rynchopetera-containing serum, cisplatin, and drug combination(B. rynchopetera-containing serum+cisplatin) for different time periods. The cell migration and invasion of A549 cells were detected by cell scratch assay and Transwell assay, respectively. Western blot was employed to determine the expression levels of B-cell lymphoma-2(Bcl-2), Bcl-2-associated X(Bax), caspase-3, cell division cycle 42(CDC42), proto-oncogene tyrosine-protein kinase SRC, and vascular endothelial growth factor(VEGF) in A549 cells. C57BL/6 mice were inoculated with Lewis cells and randomly assigned into a model control group, a B. rynchopetera group, a cisplatin group, and a drug combination(B. rynchopetera+cisplatin) group, with 12 mice per group. The body weight and the long diameter(a) and short diameter(b) of the tumor were monitored every other day during treatment, and the tumor volume(mm~3) was calculated as 0.52ab~2. After 14 days of continuous medication, the mice were sacrificed for the collection of tumor, spleen, and thymus, and the tumor inhibition rate and immune organ indexes were calculated. The tissue morphology of tumors was observed by hematoxylin-eosin(HE) staining, and the positive expression of Bax, Bcl-2, caspase-3, CDC42, SRC, and VEGF in the tumor tissue was detected by immunohistochemistry. The results indicated that B. rynchopetera and the drug combination regulated the expression levels of Bax, Bcl-2, caspase-3, CDC42, SRC, and VEGF to inhibit the proliferation, migration, and invasion of A549 cells and Lewis cells, thus playing a role in the treatment of NSCLC via multiple ways.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Medicamentos Herbarios Chinos , Neoplasias Pulmonares , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Caspasa 3 , Farmacología en Red , Factor A de Crecimiento Endotelial Vascular , Cisplatino , Simulación del Acoplamiento Molecular , Proteína X Asociada a bcl-2 , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Proliferación Celular , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China
15.
Zhongguo Zhong Yao Za Zhi ; 48(20): 5603-5611, 2023 Oct.
Artículo en Zh | MEDLINE | ID: mdl-38114153

RESUMEN

This study aims to investigate the effects of Blaps rynchopetera Fairmaire and/or cyclophosphamide on the proliferation and apoptosis of lung cancer cells and decipher the underlying mechanism. B. rynchopetera and cyclophosphamide-containing serum and blank serum were prepared from SD rats. Cell counting kit-8(CCK-8) assay was employed to examine the proliferation of lung cancer cell lines A549 and Lewis treated with corresponding agents. The Jin's formula method was used to evaluate the combined effect of the two drugs. According to the evaluation results, appropriate drug concentrations and lung cancer cell line were selected for subsequent experiments, which included control, B. rynchopetera, cyclophosphamide, B. rynchopetera + cyclophosphamide, and B. rynchopetera + Wnt/ß-catenin pathway agonist lithium chloride(LiCl) groups. Immunocytochemistry was employed to measure the expression of proliferation-related proteins in Lewis cells after drug interventions. Flow cytometry was employed to determine the cell cycle and apoptosis. The expression levels of proliferating cell nuclear antigen(PCNA), cyclinD1, B-cell lymphoma 2(Bcl-2), Bcl-2-assiocated X protein(Bax), Wnt1, and ß-catenin were determined by Western blot. The results showed that B. rynchopetera and/or cyclophosphamide significantly inhibited the proliferation of A549 and Lewis cells. Compared with B. rynchopetera alone, the combination increased the inhibition rate on cell proliferation. The combination of B. rynchopetera and cyclophosphamide demonstrated a synergistic effect according to Jin's formula-based evaluation. Compared with the control group, the B. rynchopetera, cyclophosphamide, and B. rynchopetera + cyclophosphamide groups showed increased proportion of Lewis cells in G_0/G_1 phase, increased apoptosis rate, up-regulated expression of Bax, and down-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and ß-catenin. Compared with the cyclophosphamide group, the combination group showed increased proportion of cells in G_0/G_1 phase, increased apoptosis rate, up-regulated expression of Bax, and down-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and ß-catenin. Compared with the B. rynchopetera group, the B. rynchopetera + LiCl group had deceased proportion of cells in G_0/G_1 phase, decreased apoptosis rate, down-regulated expression of Bax, and up-regulated expression of PCNA, cyclinD1, Bcl-2, Wnt1, and ß-catenin. The results indicated that B. rynchopetera could inhibit the proliferation, arrest the cell cycle, and induce the apoptosis of lung cancer cells by inhibiting the Wnt/ß-catenin signaling pathway. Moreover, B. rynchopetera had a synergistic effect with cyclophosphamide.


Asunto(s)
Neoplasias Pulmonares , Vía de Señalización Wnt , Ratas , Animales , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , beta Catenina/genética , beta Catenina/metabolismo , Antígeno Nuclear de Célula en Proliferación , Proteína X Asociada a bcl-2/metabolismo , Ratas Endogámicas Lew , Ratas Sprague-Dawley , Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proliferación Celular , Ciclofosfamida , Línea Celular Tumoral
16.
Beilstein J Org Chem ; 19: 982-990, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37404798

RESUMEN

The three-component reaction of isoquinolines, dialkyl acetylenedicarboxylates, and 5,6-unsubstituted 1,4-dihydropyridines in acetonitrile at room temperature afforded functionalized isoquinolino[1,2-f][1,6]naphthyridines in good yields and with high diastereoselectivity. More importantly, the formal [2 + 2] cycloaddition reaction of dialkyl acetylenedicarboxylates and 5,6-unsubstituted 1,4-dihydropyridines in refluxing acetonitrile gave unique 2-azabicyclo[4.2.0]octa-3,7-dienes as major products and 1,3a,4,6a-tetrahydrocyclopenta[b]pyrroles as minor products via further rearrangement.

17.
Epilepsia ; 63(1): 120-129, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34786694

RESUMEN

OBJECTIVE: Vigabatrin (VGB) is the first-line treatment for infantile spasms (IS). Previous studies have shown that VGB exposure may cause vigabatrin-associated brain abnormalities on magnetic resonance imaging (MRI) (VABAM). Based on previous studies, this study aimed to go further to explore the possible risk factors and the incidence of VABAM. In addition, diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) were compared to explore whether DWI should be used as a routine examination sequence when MRI is performed in children receiving VGB. METHODS: Children with IS receiving VGB were selected as the study subjects. Whether VABAM occurred or not was categorized as the VABAM group and the non-VABAM group, respectively. Their general clinical data and medication exposure were collected. The possible risk factors of VABAM and different MRI sequences were compared and statistically analyzed. RESULTS: A total of 77 children with IS were enrolled in the study, of which 25 (32.5%) developed VABAM. Twenty-three of the 25 VABAM cases have a peak dosage of VGB between 50 and 150 mg/kg/day. The earliest observation time of VABAM was 30 days. Regression analysis of relevant risk factors showed that the peak dosage of VGB was the risk factor for VABAM. Comparison between different MRI sequences showed that DWI is more sensitive than T2WI to the evaluation of VABAM. SIGNIFICANCE: In our study, the occurrence of VABAM was 32.5%, indicating a higher incidence than in most previous reports. In addition, we once again verified that the peak dosage of VGB was the risk factor of VABAM. Caution should be exercised that our data also suggest that VABAM may occur even using the conventional dosage of VGB (ie, 50-150 mg/kg/day). Therefore, even when using the conventional dosage of VGB, regular MRI examination should be required. Furthermore, DWI sequence should be used as a routine examination sequence when MRI is performed in children with IS who are receiving VGB.


Asunto(s)
Espasmos Infantiles , Vigabatrin , Anticonvulsivantes/efectos adversos , Encéfalo/diagnóstico por imagen , Niño , Humanos , Imagen por Resonancia Magnética , Estudios Retrospectivos , Espasmos Infantiles/inducido químicamente , Espasmos Infantiles/diagnóstico por imagen , Espasmos Infantiles/tratamiento farmacológico , Vigabatrin/efectos adversos
18.
Am J Med Genet A ; 185(2): 377-383, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33205896

RESUMEN

Developmental and epileptic encephalopathy (DEE) is a severe encephalopathy in infants and early childhood. In this study we reported a recurrent de novo variant (c.3985C>T, p.R1330W) in HECW2 (HECT, C2 and WW domain containing E3 ubiquitin protein ligase 2) (MIM# 617245) identified by screening 240 patients with DEE and summarized clinical features of published DEE patients with HECW2 variants. Functionally, transcriptional knockdown of zebrafish hecw2a led to early morphological abnormalities in the brain tissues. These results suggest a potential functional link between HECW2 dysfunction and brain development.


Asunto(s)
Encefalopatías/genética , Discapacidad Intelectual/genética , Ubiquitina-Proteína Ligasas/genética , Proteínas de Pez Cebra/genética , Adolescente , Animales , Encefalopatías/epidemiología , Encefalopatías/patología , Niño , Preescolar , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Humanos , Lactante , Discapacidad Intelectual/epidemiología , Discapacidad Intelectual/patología , Masculino , Mutación/genética , Secuenciación del Exoma , Pez Cebra/genética
19.
Heart Surg Forum ; 23(6): E913-E919, 2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33399529

RESUMEN

BACKGROUND: Valve-related hemodynamics and intrinsically regulated matrix proteases are 2 determined pathogenetic factors associated with medial elastin degeneration in bicuspid aortopathy. This study analyzed the association between elastic fiber deterioration and the 2 pathogenetic factors in ascending and root morphotypes, aiming to elucidate the etiological heterogeneity between the 2 morphotypes. METHODS: Four-dimensional flow cardiac magnetic resonance was used to measure the regional wall shear stress (WSS) on the ascending aorta, and matrix metalloproteinase (MMP) expression was assessed by immunoblotting. After histopathology analysis of aortic tissue, we assessed whether elevated regional WSS and increased MMP expression corresponded with medial elastin thinning. RESULTS: Increased regional WSS corresponded with medial elastin thinning in both morphotypes. Increased expression of different MMP isoforms corresponded with medial elastin degeneration in bicuspid aortopathy. The significantly increased expression of MMP-2 corresponded with a decrease of elastic fiber thickness in the ascending morphotype (P = .046), whereas elastic fiber thinning was associated with high levels of MMP-3 expression (P = .012) in the root morphotype. No association was observed between regional WSS and MMP expression. CONCLUSION: There is no difference in the effect of valve-related hemodynamics between ascending and root morphotype, and MMPs are not involved in the process of elastic fiber degeneration induced by increased WSS. The increased expression of different MMP isoforms was observed in the context of elastic fiber degeneration between the 2 morphotypes, implying that heterogeneity between them is revealed in the different intrinsic pathway of medial elastin degradation.


Asunto(s)
Aorta/diagnóstico por imagen , Enfermedades de la Aorta/etiología , Enfermedad de la Válvula Aórtica Bicúspide/diagnóstico , Hemodinámica/fisiología , Enfermedades de la Aorta/diagnóstico , Enfermedad de la Válvula Aórtica Bicúspide/complicaciones , Enfermedad de la Válvula Aórtica Bicúspide/fisiopatología , Femenino , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estrés Mecánico
20.
Analyst ; 144(13): 4081-4085, 2019 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-31169284

RESUMEN

Chelerythrine (CHE) is one of the potential drugs for cancer treatments. The interaction between hairpin DNA and CHE has been investigated by spectral and mass spectrometry methods. In this paper, the stability of hairpin DNA with different loop bases and its interaction with CHE were explored with a single α-hemolysin (α-HL) nanopore sensing interface. The results showed that the characteristic current pulses not only relate to the loop composition changes of the hairpin DNA, but also provide interaction information between CHE and the hairpin DNA molecules. The dwell time of current pulses for hairpin DNA was significantly increased (hundreds of ms) due to the addition of CHE, and two characteristic current distributions were recognized for the hairpin with T3 and C3 loops. The two characteristic current groups could be ascribed to the hairpin DNA and the ones with CHE. This study indicates that it is possible to study the interaction between single CHE and single hairpin DNA molecules by the single-nanopore sensing interface as an alternative method to conventional spectrometric methods for therapeutic mechanism and drug screening purposes.


Asunto(s)
Antineoplásicos/química , Benzofenantridinas/química , ADN/química , Nanoporos , ADN/genética , Técnicas Electroquímicas/métodos , Proteínas Hemolisinas/química , Secuencias Invertidas Repetidas , Mutación
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