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1.
BMC Plant Biol ; 24(1): 540, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872080

RESUMEN

BACKGROUND: Diosgenin is an important steroidal precursor renowned for its diverse medicinal uses. It is predominantly sourced from Dioscorea species, particularly Dioscorea zingiberensis. Dioscorea zingiberensis has an ability to accumulate 2-16% diosgenin in its rhizomes. In this study, a diverse population of 180 D. zingiberensis accessions was used to evaluate the genomic regions associated with diosgenin biosynthesis by the genome wide association study approach (GWAS). RESULTS: The whole population was characterized for diosgenin contents from tubers by gas chromatography mass spectrometry. The individuals were genotyped by the genotyping-by-sequencing approach and 10,000 high-quality SNP markers were extracted for the GWAS. The highest significant marker-trait-association was observed as an SNP transversion (G to T) on chromosome 10, with 64% phenotypic variance explained. The SNP was located in the promoter region of CYP94D144 which is a member of P450 gene family involved in the independent biosynthesis of diosgenin from cholesterol. The transcription factor (TF) binding site enrichment analysis of the promoter region of CYP94D144 revealed NAC TF as a potential regulator. The results were further validated through expression profiling by qRT-PCR, and the comparison of high and low diosgenin producing hybrids obtained from a bi-parental population. CONCLUSIONS: This study not only enhanced the understanding of the genetic basis of diosgenin biosynthesis but also serves as a valuable reference for future genomic investigations on CYP94D144, with the aim of augmenting diosgenin production in yam tubers.


Asunto(s)
Dioscorea , Diosgenina , Estudio de Asociación del Genoma Completo , Tubérculos de la Planta , Polimorfismo de Nucleótido Simple , Diosgenina/metabolismo , Dioscorea/genética , Dioscorea/metabolismo , Tubérculos de la Planta/genética , Tubérculos de la Planta/metabolismo , Variación Genética
2.
Langmuir ; 40(18): 9579-9591, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38657205

RESUMEN

Herein, a fiber-supported iron-based ionic liquid as a type of fibrous catalyst has been developed for the synthesis of bioactive 3,4-dihydropyrimidin-2-(1H)-ones (DHPMs) via three-component Biginelli reactions in a cleaner manner. The described fibrous catalyst was obtained from the commercially available polyetheretherketone (PEEK) fiber by postfunctionalization processes and was characterized and analyzed in detail by means of diversified technologies. Furthermore, the fiber-supported iron-based ionic liquids could mediate the classical three-component Biginelli reactions to proceed smoothly to gain a variety of substituted DHPMs with yields of up to 99%. The superior catalytic activities of the fibrous catalyst were ascribed to the quasi-homogeneous medium by ionic liquids generated in the surface layer of the PEEK fiber, which could afford an appropriate reaction zone and could further be available for the aggregation of substrates to facilitate the three-component reaction. Notably, the fibrous catalyst is available for recycling over 10 runs just by a pair of tweezers, and the operational procedure was capable of enlarging the catalytic system to the gram-scale without any performance degradation, which provided a cleaner manner to take advantage of the iron-based catalyst in organic synthesis with potential industrialization prospects.

3.
Langmuir ; 40(17): 8950-8960, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38623603

RESUMEN

Highly selective synthesis of primary amines from renewable biomass has attracted increasing attention, but it still faces great challenges in chemical industry applications. In this study, an electron-rich Ru catalyst was constructed by doping N into coffee biochar using a one-pot carbonization method (Ru/NCB-600). Ru/NCB-600 showed high catalytic activity and yield for the reductive amination of furfural with green and cheap NH3 and H2. The excellent catalytic performance of Ru/NCB-600 was closely correlated to the formation of electron-rich Ruδ- species (Ruδ--Nxδ+), which endowed Ru/NCB-600 with an enhanced H2 adsorption and activation ability. Ru/NCB-600 showed a high formation rate of 95.6 gfurfurylamine·gRu-1·h-1 and a high yield of furfurylamine (98.6%) at 50 °C. Ru/NCB-600 can also be used for the reductive amination of various carbonyl compounds in good to excellent yield (95.4-99%). This study thus provides a potential pathway for the highly selective reductive amination of carbonyl compounds by regulating the electron density of Ru.

4.
Biomacromolecules ; 25(7): 4449-4468, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38819927

RESUMEN

The γ-cyclodextrin (γ-CD) metal-organic frameworks (CD-MOF-1) consist of γ-CD and potassium (K+) ions through coordinating an eight-coordinated K+ ion with two C5-linked oxygen and C6-linked hydroxyl (C5-O/C6-OH) groups in the primary faces of adjacent γ-CD units and two C2- and C3-linked hydroxyl (C2-OH/C3-OH) groups in the secondary faces. Herein, we found polysaccharide gels with only C2-OH/C3-OH or C5-O/C6-OH groups in pyranoid rings can form four-coordinated K+ ions and then coordinate γ-CD in a KOH solution for CD-MOF-1 growth. Exposure of C2-OH/C3-OH or C5-O/C6-OH groups in polysaccharide gels is important to form active four-coordinated K+ ions. Mechanism supporting this work is that four-coordinated K+ ion sites are first formed after coordinating C2-OH/C3-OH groups in pectin and then coordinating C5-O/C6-OH groups in the primary faces of γ-CD units. Alternatively, four-coordinated K+ ions with C5-O/C6-OH groups in chitosan can coordinate the C2-OH/C3-OH groups in the secondary faces of γ-CD units. Mechanism of CD-MOF-1 growing on pectin and chitosan gels through the proposed four-coordinated K+ ions is also universally applicable to other polysaccharide gels with similar C2-OH/C3-OH or C5-O/C6-OH groups such as alginate gel. Based on this mechanism, we developed pectin and chitosan gel-based CD-MOF-1 composites and exemplified applications of them in antibacterial and organic dye removal. To help future research and applications of this mechanism, we share our theoretical assumption for further investigations that any matrices with an ortho-hydroxyl carbon chain or ortho-hydroxyl ether structures may form four-coordinated K+ ions for CD-MOF-1 growth. The proposed mechanism will broaden the development of novel CD-MOF-1 composites in various fields.


Asunto(s)
Geles , Potasio , Potasio/química , Geles/química , Porosidad , gamma-Ciclodextrinas/química , Estructuras Metalorgánicas/química , Polisacáridos/química , Pectinas/química , Iones/química
5.
Inorg Chem ; 63(32): 15154-15160, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39080828

RESUMEN

Recently, organic-inorganic hybrid perovskites exhibiting facile structural phase transitions have accumulated significant attention due to their switchable second-order nonlinear optical (NLO) properties, which hold significant promise for next-generation intelligent optoelectronic devices. In this study, we present a novel one-dimensional hexagonal hybrid perovskite, (4-methoxypiperidinium)CdCl3, which undergoes a reversible high-temperature structural phase transition at 389 K. Notably, (4-methoxypiperidinium)CdCl3 demonstrates switchable second-order NLO and dielectric properties, accompanied by symmetry breaking from the centrosymmetric Pnma to noncentrosymmetric Pna21 space group. Variable-temperature structure analyses reveal that this transition is mainly driven by the order-disorder transformation of the 4-methoxypiperidinium cations. Furthermore, it also features a promising photoluminescence performance with blue-light emission and a long lifetime of 25.34 ns. It is anticipated that this study will expand the family of hybrid perovskites exhibiting high-temperature phase transitions and offer valuable guidance for the design of new NLO switching materials with superior optoelectronic properties.

6.
J Biochem Mol Toxicol ; 38(7): e23759, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39003567

RESUMEN

Fetal growth restriction (FGR) severely affects the health outcome of newborns and represents a major cause of perinatal morbidity. The precise involvement of circCULT1 in the progression of FGR remains unclear. We performed next-generation sequencing and RT-qPCR to identify differentially expressed circRNAs in placental tissues affected by FGR by comparing them with unaffected counterparts. Edu, flow cytometry, and transwell assay were conducted to detect HTR8/SVneo cell's function in regard to cell proliferation, migration, and invasion. The interaction between circCUL1 and hsa-miR-30e-3p was assessed through dual-luciferase reporter assays, validation of the interaction between circCUL1 and ANXA1 was performed using RNA pulldown and immunoprecipitation assays. Western blot analysis was performed to evaluate protein levels of autophagy markers and components of the PI3K/AKT signaling pathway. A knockout (KO) mouse model was established for homologous mmu-circ-0001469 to assess fetal mouse growth and development indicators. Our findings revealed an upregulation of circCUL1 expression in placental tissues from patients with FGR. We found that suppression of circCUL1 increased the trophoblast cell proliferation, migration, and invasion, circCUL1 could interact with hsa-miR-30e-3p. Further, circCUL1 stimulated autophagy, modulating trophoblast cell autophagy via the ANXA1/PI3K/AKT pathway, and a notable disparity was observed, with KO mice displaying accelerated embryo development and exhibiting heavier placentas in comparison to wild-type C57BL/6 mice. By modulating the ANXA1/PI3K/AKT signaling pathway through the interaction with hsa-miR-30e-3p, circCUL1 promotes autophagy while concurrently suppressing trophoblast cell proliferation, migration, and invasion. These findings offer novel insights into potential diagnostic markers and therapeutic targets for FGR research.


Asunto(s)
Autofagia , Movimiento Celular , Retardo del Crecimiento Fetal , MicroARNs , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Trofoblastos , Animales , Femenino , Humanos , Ratones , Embarazo , Anexina A1 , Retardo del Crecimiento Fetal/metabolismo , Retardo del Crecimiento Fetal/genética , Retardo del Crecimiento Fetal/patología , Ratones Noqueados , MicroARNs/metabolismo , MicroARNs/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Transducción de Señal , Trofoblastos/metabolismo , Trofoblastos/patología
7.
Mem Cognit ; 52(5): 1210-1227, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38393534

RESUMEN

Investigations of information-seeking often highlight people's tendency to forgo financial reward in return for advance information about future outcomes. Most of these experiments use tasks in which reward contingencies are described to participants. The use of such descriptions leaves open the question of whether the opportunity to obtain such noninstrumental information influences people's ability to learn and represent the underlying reward structure of an experimental environment. In two experiments, participants completed a two-armed bandit task with monetary incentives where reward contingencies were learned via trial-by-trial experience. We find, akin to description-based tasks, that participants are willing to forgo financial reward to receive information about a delayed, unchangeable outcome. Crucially, however, there is little evidence this willingness to pay for information is driven by an inaccurate representation of the reward structure: participants' representations approximated the underlying reward structure regardless of the presence of advance noninstrumental information. The results extend previous conclusions regarding the intrinsic value of information to an experience-based domain and highlight challenges of probing participants' memories for experienced rewards.


Asunto(s)
Recompensa , Humanos , Adulto , Adulto Joven , Masculino , Femenino , Aprendizaje/fisiología , Conducta en la Búsqueda de Información/fisiología
8.
Plant Dis ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982672

RESUMEN

Pomegranate (Punica granatum) is an important fruit crop for therapeutic and food applications. In June 2022, brown spots were observed on the fruit surface of pomegranate cultivar named Guangyan in Mengzi (23°20'6''N,103°25'5''E), Yunnan, China. The early spots appeared as circular or irregular lesions, measuring 1~1.5 mm in diameter. They were light brown with a clear boundary between disease and healthy tissues. Over time, these spots developed into polygonal lesions covering the entire fruit surface. Eventually, the diseased fruits decayed, and more than 50% of fruits were infected in pomegranate orchards. The tissues from the interface between health and disease were cut down, immersed in 75% ethanol for 15 s, then 5% NaOCl disinfecting for 2 min, washed three times with sterile water, and the PDA cultured at 26 °C in an incubator under dark conditions. Twenty-five samples were collected for pathogen isolation, ten fungal isolates were obtained by single spore germination, and these isolates had similar morphological characters. The colonies were white with 81 mm diameter at 7 days of incubation, containing undulate edges with dense aerial mycelium. After 14 days, the black conidiomata formed superficially, gathering into black droplets. Conidiogenous cells were hyaline, short, and filiform. Conidia were fusiform, straight or slightly curved, and comprised five cells, 24.12 to 34.53 (x̄=29.78) µm × 4.21 to 12.15 (x̄=8.68) µm (n=50). The three median cells were 13.13 to 25.22 µm (x̄=18.54), dark brown, whose septa and periclinal walls were darker than the other two cells. The apical cells showed two to four appendages, 12.31 to 29.15 (x̄=21.56) µm. Only a single appendage was found on the basal cell, 2.34 to 7.16 µm. Based on morphological features, these isolates were identified as Neopestalotiopsis clavispora (Maharachchikumbura et al., 2012, 2014). Molecular identification of isolate YNSL-3 was performed by amplification and sequencing of ITS4/ITS5, BT2A/ BT2B and EF1-728F/EF-2, respectively (White et al. 1990, Glass et al.1995, Carbone et al. 1999, O'Donnell et al. 1998). These base sequences were deposited in GenBank with accession numbers OQ891378 (ITS), OR088917 (Tef) and OR513439(Tub), respectively. BLAST searches of the sequences revealed 100% (478/478 bp), 100% (484/484 bp), and 94.67% (426/450 bp) homology with those of N. clavispora NM16311a from GenBank (LC209216, LC209220, and LC209221), respectively. Phylogenetic analysis (IQ-TREE) by maximum likelihood method showed that the isolate YNSL-3 was clustered with N. clavispora. The pathogenicity was tested with the isolate of YNSL-3, YNSL-5 and YNSL-8 by detached assay. The fruit surface of pomegranate cultivar Guangyan was wounded with a sterilized needle. The mycelial blocks (5mm2) of isolates cultured on PDA for 7 days were attached to the points of inoculation. Controls were inoculated with sterile PDA agar. All inoculated fruits were maintained in a growth chamber at 26°C with 75% relative humidity. The test was performed thrice. The brown lesions were observed after 7 days, whereas the controls showed no symptoms. The same pathogens reisolated were identical to the original isolates based on morphological characterization and molecular analyses. N. clavispora could cause different diseases in many plants (Rajashekara et al. 2023, Loredana et al. 2020). To our knowledge, this is the first report of fruit brown spot on Punica granatum caused by N. clavispora in China. This finding will help improve management strategies against the fruit brown spots on P. granatum in China.

9.
Nanomaterials (Basel) ; 14(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38535668

RESUMEN

Carbon nanotube (CNT)-based networks are promising reinforcements for polymer nanocomposites without the issue of CNT agglomeration. In this study, the CNT junction, a vital and representative structure of CNT-based networks, was applied as the reinforcement of the polyethylene (PE) matrix. The tensile properties of the CNT-junction/PE nanocomposite were investigated via molecular dynamics (MD) simulations and compared with those of pure PE matrix and conventional CNT/PE nanocomposites. The CNT junction was found to significantly increase the mechanical properties of the PE matrix. The Young's modulus, yield strength, and toughness rose by 500%, 100%, and 200%, respectively. This mechanism is related to the enhanced interfacial energy, which makes the polymer matrix denser and stimulates the bond and angle deformations of the polymer chains. Furthermore, the CNT junction demonstrated a more profitable reinforcement efficiency compared to conventional straight CNTs in the PE matrix. Compared to the ordinary CNT/PE model, the improvements in the Young's modulus and toughness induced by the CNT junction were up to 60% and 25%. This is attributed to the reduced mobility induced by the geometry of the CNT junction and stronger interfacial interactions provided by the Stone-Wales defects of the CNT junction, slowing down the void propagation of the nanocomposite. With the understanding of the beneficial reinforcing effect of the CNT junction, this study provides valuable insights for the design and application of CNT-based networks in polymer nanocomposites.

10.
ACS Nano ; 18(13): 9670-9677, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38516986

RESUMEN

Employing water as a hydrogen source to participate in the hydrogen atom transfer (HAT) process is a low-cost and carbon-free process demonstrating great economic and environmental potential in catalysis. However, the low efficiency of hydrogen atom abstraction from water leads to slow kinetics of HAT for most hydrogenative reactions. Here, we prepared ultrathin Bi4O5Cl2 nanosheets where the surface can be in situ reconstructed via hydroxylation under light illumination to facilitate the abstraction of hydrogen atoms from pure water for efficient nitrogen fixation. Consequently, the isotope labeling in situ Fourier-transform infrared spectroscopy (FT-IR) involving H2O and D2O has clearly revealed that the hydroxyl groups tend to be adsorbed on the chloride vacancy sites on the Bi4O5Cl2 surface to form hydroxylated surfaces, where the hydroxylated photocatalyst surface enables partial dehydrogenation of water into H2O2, allowing the utilization of H atoms for efficient of N2 hydrogenation via HAT steps. This work elucidates the in-depth reaction mechanism of hydrogen atom extraction from H2O molecules via the light-generated chloride vacancy to promote photocatalytic nitrogen fixation, ultimately enabling the inspiration and providing crucial rules for the design of important functional materials that can efficiently deliver active hydrogen for chemical synthesis.

11.
Front Pharmacol ; 15: 1348688, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948474

RESUMEN

Purpose: To evaluate the cost-effectiveness of sotorasib versus docetaxel in non-small cell lung cancer (NSCLC) patients with KRASG12C mutation from the China and United States'social perspective. Materials and Methods: A Markov model that included three states (progression-free survival, post-progression survival, and death) was developed. Incremental cost-effectiveness ratio (ICER), quality-adjusted life-year (QALY), and incremental QALY were calculated for the two treatment strategies. One-way sensitivity analysis was used to investigate the factors that had a greater impact on the model results, and tornado diagrams were used to present the results. Probabilistic sensitivity analysis was performed with 1,000 Monte Carlo simulations. Assume distributions based on parameter types and randomly sample all parameter distributions each time., The results were presented as cost-effectiveness acceptable curves. Results: This economic evaluation of data from the CodeBreak 200 randomized clinical trial. In China, sotorasib generated 0.44 QAYL with a total cost of $84372.59. Compared with docetaxel, the ICER value of sotorasib was $102701.84/QALY, which was higher than willingness to pay (WTP), so sotorasib had no economic advantage. In the US, sotorasib obtained 0.35 QALY more than docetaxel, ICER was $15,976.50/QALY, which was more than 1 WTP but less than 3 WTP, indicating that the increased cost of sotorasib was acceptable. One-way sensitivity analysis showed that the probability of sotorasib having economic benefits gradually increased when the cost of follow-up examination was reduced in China. And there was no influence on the conclusions within the range of changes in China. When the willingness to pay (WTP) exceeds $102,500, the probability of sotorasib having cost effect increases from 0% to 49%. Conclusion: Sotorasib had a cost effect from the perspective in the United States. However, sotorasib had no cost effect from the perspective in China, and only when the WTP exceeds $102,500, the probability of sotorasib having cost effect increases from 0% to 49%.

12.
World J Clin Cases ; 12(20): 4057-4064, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39015897

RESUMEN

BACKGROUND: Psychological factors such as anxiety and depression will not only aggravate the symptoms of chronic obstructive pulmonary disease (COPD) patients and reduce the quality of life of patients, but also affect the treatment effect and long-term prognosis. Therefore, it is of great significance to explore the clinical application of senile comprehensive assessment in the treatment of COPD and its influence on psychological factors such as anxiety and depression. AIM: To explore the clinical application of comprehensive geriatric assessment in COPD care and its impact on anxiety and depression in elderly patents. METHODS: In this retrospective study, 60 patients with COPD who were hospitalized in our hospital from 2019 to 2020 were randomly divided into two groups with 30 patients in each group. The control group was given routine nursing, and the observation group was given comprehensive assessment. Clinical symptoms, quality of life [COPD assessment test (CAT) score], anxiety and depression Hamilton Anxiety Rating Scale (HAMA) and Hamilton Depression Rating Scale (HAMD) were compared between the two groups. RESULTS: CAT scores in the observation group decreased from an average of 24.5 points at admission to an average of 18.3 points at discharge, and in the control group from an average of 24.7 points at admission to an average of 18.3 points at discharge. The average score was 22.1 (P < 0.05). In the observation group, HAMA scores decreased from 14.2 points at admission to 8.6 points at discharge, and HAMD scores decreased from 13.8 points at admission to 7.4 points at discharge. The mean HAMD scores in the control group decreased from an average of 14.5 at admission to an average of 12.3 at discharge, and from an average of 14.1 at admission to an average of 11.8 at discharge. CONCLUSION: The application of comprehensive geriatric assessment in COPD care has a significant effect on improving patients' clinical symptoms and quality of life, and can effectively reduce patients' anxiety and depression.

13.
Phys Rev E ; 109(1-1): 014214, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38366462

RESUMEN

Reservoir computing (RC) has been widely applied to predict the chaotic dynamics in many systems. Yet much broader areas related to nonsmooth dynamics have seldom been touched by the RC community which have great theoretical and practical importance. The generalization of RC to this kind of system is reported in this paper. The numerical work shows that the conventional RC with a hyperbolic tangent activation function is not able to predict the dynamics of nonsmooth systems very well, especially when reconstructing attractors (long-term prediction). A nonsmooth activation function with a piecewise nature is proposed. A kind of physics-informed RC scheme is established based on this activation function. The feasibility of this scheme has been proven by its successful application to the predictions of the short- and long-term (reconstructing chaotic attractor) dynamics of four nonsmooth systems with different complexity, including the tent map, piecewise linear map with a gap, both noninvertible and discontinuous compound circle maps, and Lozi map. The results show that RC with the new activation function is efficient and easy to run. It can make perfectly both short- and long-term predictions. The precision of reconstructing attractors depends on their complexity. This work reveals that, to make efficient predictions, the activation function of an RC approach should match the smooth or nonsmooth nature of the dynamical systems.

14.
Life Sci ; 338: 122412, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38191051

RESUMEN

AIMS: Hepatitis C virus (HCV) relies on the viral and host factors to complete its life cycle. It has evolved to profit from Akt activation at some stage in its life cycle through various mechanisms, notably by activating lipogenesis, which is crucial for infectious virions production. MATERIALS AND METHODS: By employing an Akt-specific inhibitor, the impact of Akt on intracellular and extracellular infectivity was investigated. To ascertain the role of Akt in the HCV life cycle, the two-part cell culture-derived HCV infection protocol utilizing Akt1 small interfering RNAs (siRNAs) was implemented. The impact of Akt1 on intracellular HCV transition was determined using membrane flotation assay and proximity ligation assay coupled with Anti-Rab7 immunoprecipitation and immunofluorescence. KEY FINDINGS: Akt1 silencing reduced infectious virions release to a degree comparable to that of ApoE, a host component involved in the HCV assembly and release, suggesting Akt1 was critical in the late stage of the HCV life cycle. Extracellular infectivity of HCV was inhibited by brefeldin A, and the inhibitory effect was augmented by Akt1 silencing and partially restored by ectopic Akt1 expression. Immunofluorescence revealed that Akt1 inhibition suppressed the interaction between HCV core protein and lipid droplet. Akt1 silencing impeded the transition of HCV from the endoplasmic reticulum to the endosome and hence inhibited the secretion of HCV infectious virions from the late endosome. SIGNIFICANCE: Our study demonstrates that Akt1 has an impact on the lipogenesis pathway and plays a critical role in the assembly and secretion of infectious HCV.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Retículo Endoplásmico/metabolismo , Endosomas , Hepacivirus/metabolismo , Hepatitis C/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/metabolismo , Virión , Ensamble de Virus/fisiología
15.
Acad Radiol ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38458887

RESUMEN

BACKGROUND: Gliomas are the most common primary brain tumours and constitute approximately half of all malignant glioblastomas. Unfortunately, patients diagnosed with malignant glioblastomas typically survive for less than a year. In light of this circumstance, genotyping is an effective means of categorising gliomas. The Ki67 proliferation index, a widely used marker of cellular proliferation in clinical contexts, has demonstrated potential for predicting tumour classification and prognosis. In particular, magnetic resonance imaging (MRI) plays a vital role in the diagnosis of brain tumours. Using MRI to extract glioma-related features and construct a machine learning model offers a viable avenue to classify and predict the level of Ki67 expression. METHODS: This study retrospectively collected MRI data and postoperative immunohistochemical results from 613 glioma patients from the First Affliated Hospital of Nanjing Medical University. Subsequently, we performed registration and skull stripping on the four MRI modalities: T1-weighted (T1), T2-weighted (T2), T1-weighted with contrast enhancement (T1CE), and Fluid Attenuated Inversion Recovery (FLAIR). Each modality's segmentation yielded three distinct tumour regions. Following segmentation, a comprehensive set of features encompassing texture, first-order, and shape attributes were extracted from these delineated regions. Feature selection was conducted using the least absolute shrinkage and selection operator (LASSO) algorithm with subsequent sorting to identify the most important features. These selected features were further analysed using correlation analysis to finalise the selection for machine learning model development. Eight models: logistic regression (LR), naive bayes, decision tree, gradient boosting tree, and support vector classification (SVM), random forest (RF), XGBoost, and LightGBM were used to objectively classify Ki67 expression. RESULTS: In total, 613 patients were enroled in the study, and 24,455 radiomic features were extracted from each patient's MRI. These features were eventually reduced to 36 after LASSO screening, RF importance ranking, and correlation analysis. Among all the tested machine learning models, LR and linear SVM exhibited superior performance. LR achieved the highest area under the curve score of 0.912 ± 0.036, while linear SVM obtained the top accuracy with a score of 0.884 ± 0.031. CONCLUSION: This study introduced a novel approach for classifying Ki67 expression levels using MRI, which has been proven to be highly effective. With the LR model at its core, our method demonstrated its potential in signalling a promising avenue for future research. This innovative approach of predicting Ki67 expression based on MRI features not only enhances our understanding of cell activity but also represents a significant leap forward in brain glioma research. This underscores the potential of integrating machine learning with medical imaging to aid in the diagnosis and prognosis of complex diseases.

16.
Org Lett ; 26(23): 4857-4862, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38838191

RESUMEN

The efficient construction of π-conjugated polycyclic heteroarenes represents a significant task in the field of functional materials. A one-step oxidative tandem cyclization of aromatic acids with (benzo)thiophenes was developed to access planar sulfur-containing polycyclic heteroarenes. This protocol undergoes intermolecular cross-dehydrogenative coupling followed by intramolecular Friedel-Crafts acylation and provides a facile pathway to planar polycyclic compounds from inexpensive reactants. The synthesized heteroarenes serving as lipid-droplet-targeted probes exhibit outstanding performance with favorable biocompatibility and photostability.

17.
Toxicol Lett ; 398: 127-139, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38914176

RESUMEN

Increasing epidemiological evidence has shown that PM2.5 exposure is significantly associated with the occurrence of osteoporosis. It has been well demonstrated that PM2.5 exposure enhanced the differentiation and function of osteoclasts by indirectly causing chronic inflammation, while the mechanism in osteoblasts remains unclear. In our study, toxic effects were evaluated by direct exposure of 20-80 µg/ml PM2.5 to MC3T3-E1 cells and BMSCs. The results showed that PM2.5 exposure did not affect cell viability via proliferation and apoptosis, but significantly inhibited osteoblast differentiation in a dose-dependent manner. Osteogenic transcription factors Runx2 and Sp7 and other biomarkers Alp and Ocn decreased after PM2.5 exposure. RNA-seq revealed TGF-ß signaling was involved in PM2.5 exposure inhibited osteoblast differentiation, which led to P-Smad1/5 and P-Smad2 reduction in the nucleus by increasing the ubiquitination and degradation of Smad4. At last, the inflammation response increased in MC3T3-E1 cells with PM2.5 exposure. Moreover, the mRNA levels of Mmp9 increased in bone marrow-derived macrophage cells treated with the conditional medium collected from MC3T3-E1 cells exposed to PM2.5. Overall, these results indicated that PM2.5 exposure inhibits osteoblast differentiation and concurrently increases the maturation of osteoclasts. Our study provides in-depth mechanistic insights into the direct impact of PM2.5 exposure on osteoblast, which would indicate the unrecognized role of PM2.5 on osteoporosis.


Asunto(s)
Diferenciación Celular , Osteoblastos , Material Particulado , Proteína Smad4 , Ubiquitinación , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , Proteína Smad4/metabolismo , Proteína Smad4/genética , Ratones , Material Particulado/toxicidad , Ubiquitinación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Contaminantes Atmosféricos/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Proteolisis/efectos de los fármacos
18.
Sci Total Environ ; 917: 170317, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38301787

RESUMEN

Lead (Pb), a pervasive and ancient toxic heavy metal, continues to pose significant neurological health risks, particularly in regions such as Southeast Asia. While previous research has primarily focused on the adverse effects of acute, high-level lead exposure on neurological systems, studies on the impacts of chronic, low-level exposure are less extensive, especially regarding the precise mechanisms linking ferroptosis - a novel type of neuron cell death - with cognitive impairment. This study aims to explore the potential effects of chronic low-level lead exposure on cognitive function and hippocampal neuronal ferroptosis. This research represents the first comprehensive investigation into the impact of chronic low-level lead exposure on hippocampal neuronal ferroptosis, spanning clinical settings, bioinformatic analyses, and experimental validation. Our findings reveal significant alterations in the expression of genes associated with iron metabolism and Nrf2-dependent ferroptosis following lead exposure, as evidenced by comparing gene expression in the peripheral blood of lead-acid battery workers and workers without lead exposure. Furthermore, our in vitro and in vivo experimental results strongly suggest that lead exposure may precipitate cognitive dysfunction and induce hippocampal neuronal ferroptosis. In conclusion, our study indicates that chronic low-level lead exposure may activate microglia, leading to the promotion of ferroptosis in hippocampal neurons.


Asunto(s)
Ferroptosis , Plomo , Humanos , Plomo/toxicidad , Cognición , Aprendizaje Automático , Biología Computacional , Hipocampo , Neuronas
19.
FEBS J ; 291(6): 1264-1274, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38116713

RESUMEN

HCV NS5A is a dimeric phosphoprotein involved in HCV replication. NS5A inhibitors are among direct-acting antivirals (DAA) for HCV therapy. The Y93H mutant of NS5A is resistant to NS5A inhibitors, but the precise mechanism remains unclear. In this report, we proposed a Ser38-His93-Asn91 triad to dissect the mechanism. Using pymol 1.3 software, the homology structure of JFH1 NS5A was determined based on the dimer structure of genotype 1b extracted from the database Protein DataBank (www.ebi.ac.uk/pdbsum) with codes 1ZH1 and 3FQM/3FQQ. FLAG-NS5A-WT failed to form dimer in the absence of nonstructural proteins from subgenomic replicon (NS3-5A); however, FLAG-NS5A-Y93H was able to form dimer without the aid of NS3-5A. The Ser38-His93-Asn91 triad in the dimer of the Y93H variant predicts a structural crash of the cleft receiving the NS5A inhibitor daclatasvir. The dimerization assay revealed that the existence of JFH1-NS5A-1ZH1 and -3FQM homology dimers depended on each other for existence and that both NS5A-WT 1ZH1 and 3FQM dimers cooperated to facilitate RNA replication. However, NS5A-Y93H 1ZH1 alone could form dimer and conduct RNA replication in the absence of the 3FQM structure. In conclusion, this study provides novel insight into the functional significance of the Ser38-His93-Asn91 triad in resistance of the Y93H variant to NS5A inhibitors.


Asunto(s)
Antivirales , Hepatitis C Crónica , Humanos , Antivirales/farmacología , Hepatitis C Crónica/tratamiento farmacológico , Genotipo , Hepacivirus/genética , Proteínas no Estructurales Virales/genética , Farmacorresistencia Viral/genética
20.
J Ethnopharmacol ; 330: 118222, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38663778

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Cinnamomum cassia Presl (Cinnamomum cassia) is a common traditional Chinese medicine, which can promote the secretion and digestion of gastric juice, improve the function of gastrointestinal tract. Cinnamaldehyde (CA) is a synthetic food flavoring in the Chinese Pharmacopoeia. AIM OF THE STUDY: This study aimed to search for the active ingredient (CA) of inhibiting H. pylori from Cinnamomum cassia, and elucidate mechanism of action, so as to provide the experimental basis for the treatment of H. pylori infection with Cinnamomum cassia. MATERIALS AND METHODS: It's in vitro and in vivo pharmacological properties were evaluated based on minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and an acute gastric inflammation model in mice infected with H. pylori. Drug safety was evaluated using the CCK8 method and high-dose administration in mice. The advantageous characteristics of CA in inhibiting H. pylori were confirmed using acidic conditions and in combination with the antibiotics. The mechanism underlying the action of CA on H. pylori was explored using scanning electron microscopy (SEM), adhesion experiments, biofilm inhibition tests, ATP and ROS release experiments, and drug affinity responsive target stability (DARTS) screening of target proteins. The protein function and target genes were verified by molecular docking and Real-Time quantitative reverse transcription PCR (qRT-PCR). RESULTS: The results demonstrated that CA was found to be the main active ingredient against H. pylori in Cinnamomum cassia in-vitro tests, with a MIC of 8-16 µg/mL. Moreover, CA effectively inhibited both sensitive and resistant H. pylori strains. The dual therapy of PPI + CA exhibited remarkable in vivo efficacy in the acute gastritis mouse model, superior to the standard triple therapy. DARTS, molecular docking, and qRT-PCR results suggested that the target sites of action were closely associated with GyrA, GyrB, AtpA, and TopA, which made DNA replication and transcription impossible, then leading to inhibition of bacterial adhesion and colonization, suppression of biofilm formation, and inhibition ATP and enhancing ROS. CONCLUSIONS: This study demonstrated the suitability of CA as a promising lead drug against H. pylori, The main mechanisms can target GyrA ect, leading to reduce ATP and produce ROS, which induces the apoptosis of bacterial.


Asunto(s)
Acroleína , Antibacterianos , Cinnamomum aromaticum , Infecciones por Helicobacter , Helicobacter pylori , Pruebas de Sensibilidad Microbiana , Animales , Acroleína/análogos & derivados , Acroleína/farmacología , Helicobacter pylori/efectos de los fármacos , Cinnamomum aromaticum/química , Antibacterianos/farmacología , Ratones , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Masculino , Simulación del Acoplamiento Molecular , Biopelículas/efectos de los fármacos
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