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1.
Theor Appl Genet ; 137(4): 87, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512468

RESUMEN

KEY MESSAGE: A total of 38 putative additive QTLs and 55 pairwise putative epistatic QTLs for tiller-related traits were reported, and the candidate genes underlying qMtn-KJ-5D, a novel major and stable QTL for maximum tiller number, were characterized. Tiller-related traits play an important role in determining the yield potential of wheat. Therefore, it is important to elucidate the genetic basis for tiller number when attempting to use genetic improvement as a tool for enhancing wheat yields. In this study, a quantitative trait locus (QTL) analysis of three tiller-related traits was performed on the recombinant inbred lines (RILs) of a mapping population, referred to as KJ-RILs, that was derived from a cross between the Kenong 9204 (KN9204) and Jing 411 (J411) lines. A total of 38 putative additive QTLs and 55 pairwise putative epistatic QTLs for spike number per plant (SNPP), maximum tiller number (MTN), and ear-bearing tiller rate (EBTR) were detected in eight different environments. Among these QTLs with additive effects, three major and stable QTLs were first documented herein. Almost all but two pairwise epistatic QTLs showed minor interaction effects accounting for no more than 3.0% of the phenotypic variance. The genetic effects of two colocated major and stable QTLs, i.e., qSnpp-KJ-5D.1 and qMtn-KJ-5D, for yield-related traits were characterized. The breeding selection effect of the beneficial allele for the two QTLs was characterized, and its genetic effects on yield-related traits were evaluated. The candidate genes underlying qMtn-KJ-5D were predicted based on multi-omics data, and TraesKN5D01HG00080 was identified as a likely candidate gene. Overall, our results will help elucidate the genetic architecture of tiller-related traits and can be used to develop novel wheat varieties with high yields.


Asunto(s)
Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Mapeo Cromosómico/métodos , Ligamiento Genético , Fitomejoramiento , Fenotipo
2.
World J Urol ; 42(1): 89, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376590

RESUMEN

PURPOSE: To investigate the effect of the postural drainage lithotripsy system developed by our experimental team on the vital signs of patient with urinary stones during the stone removal process. METHODS: Four groups of 15 subjects (0°, 10°, 40°, and 70°) were subjected to different angles of head-down tilt to measure middle cerebral artery blood flow velocity (MCAv), cerebrovascular conductance coefficient (CVCi), intracranial pressure (nICP), heart rate (HR), and mean arterial blood pressure (MAP). RESULTS: As the angle of HDT changed, MCAv values, nICP values, CVCi values, HR values, and MAP values changed significantly (all P ≤ 0.001), and the difference was statistically significant. During 10°HDT, despite a slight increase in nICP, the other measurements remained stable. During 40°HDT, only the MCAv values did not change significantly, whereas the rest of the measures were significantly altered. During 70°HDT, all indicators changed significantly. CONCLUSIONS: The significant alterations in cerebral blood flow, intracranial pressure, and hemodynamics induced during the treatment of renal residual fragments with postural drainage should be used with caution in individuals with cerebrovascular accidents. CHINA CLINICAL TRIALS REGISTRY: ChiCTR2300070671; Registration date: 2023-04-18.


Asunto(s)
Presión Intracraneal , Litotricia , Humanos , Presión Sanguínea , Frecuencia Cardíaca , Drenaje Postural , Circulación Cerebrovascular
3.
Cell Mol Biol Lett ; 29(1): 82, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822260

RESUMEN

BACKGROUND: Hepatic stellate cells (HSCs) play a crucial role in the development of fibrosis in non-alcoholic fatty liver disease (NAFLD). Small extracellular vesicles (sEV) act as mediators for intercellular information transfer, delivering various fibrotic factors that impact the function of HSCs in liver fibrosis. In this study, we investigated the role of lipotoxic hepatocyte derived sEV (LTH-sEV) in HSCs activation and its intrinsic mechanisms. METHODS: High-fat diet (HFD) mice model was constructed to confirm the expression of LIMA1. The relationship between LIMA1-enriched LTH-sEV and LX2 activation was evaluated by measurement of fibrotic markers and related genes. Levels of mitophagy were detected using mt-keima lentivirus. The interaction between LIMA1 and PINK1 was discovered through database prediction and molecular docking. Finally, sEV was injected to investigate whether LIMA1 can accelerate HFD induced liver fibrosis in mice. RESULTS: LIMA1 expression was upregulated in lipotoxic hepatocytes and was found to be positively associated with the expression of the HSCs activation marker α-SMA. Lipotoxicity induced by OPA led to an increase in both the level of LIMA1 protein in LTH-sEV and the release of LTH-sEV. When HSCs were treated with LTH-sEV, LIMA1 was observed to hinder LX2 mitophagy while facilitating LX2 activation. Further investigation revealed that LIMA1 derived from LTH-sEV may inhibit PINK1-Parkin-mediated mitophagy, consequently promoting HSCs activation. Knocking down LIMA1 significantly attenuates the inhibitory effects of LTH-sEV on mitophagy and the promotion of HSCs activation. CONCLUSIONS: Lipotoxic hepatocyte-derived LIMA1-enriched sEVs play a crucial role in promoting HSCs activation in NAFLD-related liver fibrosis by negatively regulating PINK1 mediated mitophagy. These findings provide new insights into the pathological mechanisms involved in the development of fibrosis in NAFLD.


Asunto(s)
Dieta Alta en Grasa , Vesículas Extracelulares , Células Estrelladas Hepáticas , Hepatocitos , Cirrosis Hepática , Ratones Endogámicos C57BL , Mitofagia , Animales , Humanos , Masculino , Ratones , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/patología , Cirrosis Hepática/patología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/genética , Mitofagia/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/genética , Proteínas Quinasas/metabolismo , Proteínas Quinasas/genética
4.
Planta ; 257(3): 61, 2023 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-36808254

RESUMEN

MAIN CONCLUSION: P. polyphylla selectively enriches beneficial microorganisms to help their growth. Paris polyphylla (P. polyphylla) is an important perennial plant for Chinese traditional medicine. Uncovering the interaction between P. polyphylla and the related microorganisms would help to utilize and cultivate P. polyphylla. However, studies focusing on P. polyphylla and related microbes are scarce, especially on the assembly mechanisms and dynamics of the P. polyphylla microbiome. High-throughput sequencing of the 16S rRNA genes was implemented to investigate the diversity, community assembly process and molecular ecological network of the bacterial communities in three root compartments (bulk soil, rhizosphere, and root endosphere) across three years. Our results demonstrated that the composition and assembly process of the microbial community in different compartments varied greatly and were strongly affected by planting years. Bacterial diversity was reduced from bulk soils to rhizosphere soils to root endosphere and varied over time. Microorganisms benefit to plants was selectively enriched in P. polyphylla roots as was its core microbiome, including Pseudomonas, Rhizobium, Steroidobacter, Sphingobium and Agrobacterium. The network's complexity and the proportion of stochasticity in the community assembly process increased. Besides, nitrogen metabolism, carbon metabolism, phosphonate and phosphinate metabolism genes in bulk soils increased over time. These findings suggest that P. polyphylla exerts a selective effect to enrich the beneficial microorganisms and proves the sequential increasing selection pressure with P. polyphylla growth. Our work adds to the understanding of the dynamic processes of plant-associated microbial community assembly, guides the selection and application timing of P. polyphylla-associated microbial inoculants and is vital for sustainable agriculture.


Asunto(s)
Liliaceae , Microbiota , Microbiología del Suelo , ARN Ribosómico 16S , Raíces de Plantas/microbiología , Bacterias/genética , Rizosfera , Suelo , Liliaceae/genética
5.
J Magn Reson Imaging ; 57(3): 884-896, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35929909

RESUMEN

BACKGROUND: Noninvasive determination of Notch signaling is important for prognostic evaluation and therapeutic intervention in glioma. PURPOSE: To predict Notch signaling using multiparametric (mp) MRI radiomics and correlate with biological characteristics in gliomas. STUDY TYPE: Retrospective. POPULATION: A total of 63 patients for model construction and 47 patients from two public databases for external testing. FIELD STRENGTH/SEQUENCE: A 1.5 T and 3.0 T, T1-weighted imaging (T1WI), T2WI, T2 fluid attenuated inversion recovery (FLAIR), contrast-enhanced (CE)-T1WI. ASSESSMENT: Radiomic features were extracted from CE-T1WI, T1WI, T2WI, and T2FLAIR and imaging signatures were selected using a least absolute shrinkage and selection operator. Diagnostic performance was compared between single modality and a combined mpMRI radiomics model. A radiomic-clinical nomogram was constructed incorporating the mpMRI radiomic signature and Karnofsky Performance score. The performance was validated in the test set. The radiomic signatures were correlated with immunohistochemistry (IHC) analysis of downstream Notch pathway components. STATISTICAL TESTS: Receiver operating characteristic curve, decision curve analysis (DCA), Pearson correlation, and Hosmer-Lemeshow test. A P value < 0.05 was considered statistically significant. RESULTS: The radiomic signature derived from the combination of all sequences numerically showed highest area under the curve (AUC) in both training and external test sets (AUCs of 0.857 and 0.823). The radiomics nomogram that incorporated the mpMRI radiomic signature and KPS status resulted in AUCs of 0.891 and 0.859 in the training and test sets. The calibration curves showed good agreement between prediction and observation in both sets (P= 0.279 and 0.170, respectively). DCA confirmed the clinical usefulness of the nomogram. IHC identified Notch pathway inactivation and the expression levels of Hes1 correlated with higher combined radiomic scores (r = -0.711) in Notch1 mutant tumors. DATA CONCLUSION: The mpMRI-based radiomics nomogram may reflect the intratumor heterogeneity associated with downstream biofunction that predicts Notch signaling in a noninvasive manner. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Glioma , Imágenes de Resonancia Magnética Multiparamétrica , Humanos , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Glioma/diagnóstico por imagen , Transducción de Señal
6.
Theor Appl Genet ; 136(10): 211, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37737910

RESUMEN

KEY MESSAGE: A major stable QTL for kernel number per spike was narrowed down to a 2.19-Mb region containing two potential candidate genes, and its effects on yield-related traits were characterized. Kernel number per spike (KNPS) in wheat is a key yield component. Dissection and characterization of major stable quantitative trait loci (QTLs) for KNPS would be of considerable value for the genetic improvement of yield potential using molecular breeding technology. We had previously reported a major stable QTL controlling KNPS, qKnps-4A. In the current study, primary fine-mapping analysis, based on the primary mapping population, located qKnps-4A to an interval of approximately 6.8-Mb from 649.0 to 655.8 Mb on chromosome 4A refering to 'Kenong 9204' genome. Further fine-mapping analysis based on a secondary mapping population narrowed qKnps-4A to an approximately 2.19-Mb interval from 653.72 to 655.91 Mb. Transcriptome sequencing, gene function annotation analysis and homologous gene related reports showed that TraesKN4A01HG38570 and TraesKN4A01HG38590 were most likely to be candidate genes of qKnps-4A. Phenotypic analysis based on paired near-isogenic lines in the target region showed that qKnps-4A increased KNPS mainly by increasing the number of central florets per spike. We also evaluated the effects of qKnps-4A on other yield-related traits. Moreover, we dissected the QTL cluster of qKnps-4A and qTkw-4A and proved that the phenotypic effects were probably due to close linkage of two or more genes rather than pleiotropic effects of a single gene. This study provides molecular marker resource for wheat molecular breeding designed to improve yield potential, and lay the foundation for gene functional analysis of qKnps-4A.


Asunto(s)
Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Barajamiento de ADN , Anotación de Secuencia Molecular , Fenotipo
7.
J Neurooncol ; 165(2): 301-312, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37995007

RESUMEN

PURPOSE: To explore the impact of intrathecal pemetrexed (IP) on the survival of lung adenocarcinoma (LUAC) patients with leptomeningeal metastasis (LM). METHODS: We analyzed patients with LUAC and LM who received systemic therapy after LM diagnosis at the Fujian Cancer Hospital between July 2018 and March 2022. Patients who underwent IP were assigned to the IP group; those without IP treatment were designated as the non-IP group. Propensity score matching (PSM) was performed between the two groups. RESULTS: 165 patients were enrolled: 83 and 82 in the IP and non-IP groups, respectively. After 1:1 PSM, we included 114 patients in the matched cohort. Median overall survival (OS) was 13.2 months (95% CI 10.8-15.6 months) in the IP group versus 10.1 months (95% CI 5.3-14.9 months) in the non-IP group (P = 0.488). Only Eastern Cooperative Oncology Group Performance Status (ECOG PS) was confirmed as an independent predictor for OS in the matched cohort (hazard ratio (HR) 2.03; P = 0.023). Multivariate competing-risks analysis showed that IP significantly correlated with central nervous system-related death (HR 0.31; P = 0.046). When stratified by ECOG PS, IP improved survival in patients with poor ECOG PS (PS = 2) (14.3 months vs. 1.6 months; P = 0.003). CONCLUSIONS: Intrathecal pemetrexed did not enhance OS for the entire LUAC patient with LM compared to non-intrathecal chemotherapy. However, it exhibited the potential to reduce the risk of central nervous system-related mortality and improve survival in patients with poor ECOG PS.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinomatosis Meníngea , Humanos , Pemetrexed/uso terapéutico , Neoplasias Pulmonares/patología , Puntaje de Propensión , Adenocarcinoma del Pulmón/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinomatosis Meníngea/tratamiento farmacológico , Carcinomatosis Meníngea/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
8.
Inorg Chem ; 62(23): 9249-9258, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37256938

RESUMEN

Precatalyst reconstruction in alkaline hydrogen evolution reaction (HER) usually leads to changes in the morphology, composition, and structure, thus improving the catalytic activity, which recently receives intensive attention. However, the design strategies of cathodic reconstruction and the structural features of reconstruction products have not achieved a profound understanding. Here, from the point of thermodynamic stability, metastable nickel selenite dihydrate (NiSeO3·2H2O) is deliberately fabricated as a precatalyst to comprehensively study the reconstruction dynamics in alkaline HER. Multiple in/ex situ techniques capture the geometric, component, and phase evolutions, proving that NiSeO3·2H2O can be transformed into SeO32--decorated polycrystalline NiO nanosheets with rich active sites and good conductivity under alkaline HER conditions, which act as a real catalytic active species. Density functional theory calculations demonstrate that the adsorption of SeO32- can further promote the HER activity of NiO due to the optimized free energy of water activation and hydrogen adsorption. As a result, the SeO32--NiO catalyst exhibits a low overpotential at -10 mA cm-2 (90 mV) and long-term stability (>100 h). This work highlights the targeted design of precatalyst to trigger and utilize cathodic reconstruction and provides an available method for the development of adsorption-modulated efficient electrocatalysts.

9.
Sensors (Basel) ; 23(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571607

RESUMEN

The progress of commercial VR headsets largely depends on the progress of sensor technology, the iteration of which often means longer research and development cycles, and also higher costs. With the continuous maturity and increasing competition of VR headsets, designers need to create a balance among user needs, technologies, and costs to achieve commercial competition advantages. To make accurate judgments, consumer feedback and opinions are particularly important. Due to the increasing maturity in the technology of commercial VR headsets in recent years, the cost has been continuously decreasing, and potential consumers have gradually increased. With the increase in consumer demand for virtual reality headsets, it is particularly important to establish a perceptual quality evaluation system. The relationship between consumer perception and product quality determined by evaluations of experience is improving. Using the research method implemented in this work, through semi-structured interviews and big data analysis of VR headset consumption, the perceptual quality elements of VR headsets are proposed, and the order of importance of perceptual quality attributes is determined by questionnaire surveys, quantitative analysis, and verification. In this study, the perceptual quality elements, including technical perceptual quality (TPQ) and value perceptual quality (VPQ), of 14 types of VR headsets were obtained, and the importance ranking of the VR headsets' perceptual quality attributes was constructed. In theory, this study enriches the research on VR headsets. In practice, this study provides better guidance and suggestions for designing and producing VR headsets so that producers can better understand which sensor technology has met the needs of consumers, and which sensor technology still has room for improvement.


Asunto(s)
Realidad Virtual , Humanos , Computadores , Encuestas y Cuestionarios , Retroalimentación
10.
Angew Chem Int Ed Engl ; 62(4): e202215582, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36418237

RESUMEN

Disentangled ultrahigh molecular weight polyethylene (dis-UHMWPE) has excellent processability but can be achieved under extreme conditions. Herein, we report ethylene polymerization with the binuclear half-sandwich scandium complexes C1-Sc2 and C2-Sc2 to afford UHMWPE. C1-Sc2 bearing a short linker shows higher activity and gives higher molecular weight PEs than C2-Sc2 containing a flexible spacer and the mononuclear Sc1 . Strikingly, all UHMWPEs isolated from C1-Sc2 under broad temperature range (25-120 °C) and wide ethylene pressures (2-13 bar) feature very low degree of entanglement as proved by rheological test, DSC annealing study and SEM. These dis-UHMWPEs are facilely mediated solid-state-process at 130 °C and their tensile strength and modulus reach up to 149.2 MPa and 1.5 GPa, respectively. DFT simulations reveal that the formation of dis-UHMWPE is attributed to the binuclear synergic effect and the agostic interaction between the active center and the growing chain.

11.
J Obstet Gynaecol Res ; 48(7): 1632-1640, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35577316

RESUMEN

AIM: To develop a scoring system for the prediction of a successful pregnancy. METHODS: Data were collected prospectively from women diagnosed with pregnancy from January 1, 2015, to December 31, 2018. Pregnant days, hormone levels, and gestational sac diameters were recorded. Relationships among the pregnancy days, hormones, and gestational sac were analyzed by Spearman correlation analysis. A scoring system was established and stratified by the 5th, 50th, and 95th percentile of hormone levels and gestational sac diameters on different pregnancy days. Pregnancy outcomes were predicted by the scores using quadratic polynomial regression analyses. A portable desktop analyzer was developed and the performance was evaluated by receiver operating characteristic (ROC) curve. RESULTS: In 273 successful pregnancy cases, the length of gestational days was significantly correlated to beta-human chorionic gonadotropin (ß-hCG) (r = 0.74, p < 0.001) and E2 (r = 0.79, p < 0.001) levels, and the size of the gestational sac (r = 0.88, p < 0.001). Meanwhile, the size of gestational sac was positively correlated with ß-hCG (r = 0.93, p < 0.001) and E2 (r = 0.55, p < 0.001). For 273 delivery and 103 miscarriage cases included in this study, our scoring-based prediction model rendered an area under the ROC curve (AUC) of 0.86 with the sensitivity of 78.31% and the specificity of 80.83%. CONCLUSIONS: We successfully developed a scoring-based analyzer to evaluate the viability of embryos at different gestation stages and to predict the probability of a successful delivery, which would provide a reference for clinicians in postpregnancy management.


Asunto(s)
Aborto Espontáneo , Embarazo , Aborto Espontáneo/diagnóstico , Gonadotropina Coriónica Humana de Subunidad beta , Femenino , Saco Gestacional , Humanos , Modelos Teóricos , Embarazo/estadística & datos numéricos , Probabilidad
12.
Int J Mol Sci ; 23(19)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36232928

RESUMEN

Direct-acting antivirals (DAAs) have recently revolutionized the eradication of chronic hepatitis C virus (HCV) infection. However, the effects of DAAs on the development of hepatocellular carcinoma (HCC) remain unknown. Therefore, the present study aimed to investigate immune responses to HCC influenced by DAAs in HCV-infected patients and elucidate the underlying mechanisms. We compared immune responses to 19 different HCC-related tumor-associated antigen (TAA)-derived peptides and host immune cell profiles before and 24 weeks after a treatment with DAAs in 47 HLA-A24-positive patients. The relationships between the different immune responses and phenotypic changes in immune cells were also examined. The treatment with DAAs induced four types of immune responses to TAAs and markedly altered host immune cell profiles. Prominently, reductions in the frequencies of PD-1+CD4+ and PD-1+CD8+ T cells by DAAs were associated with enhanced immune responses to TAAs. The HCV F protein was identified as contributing to the increased frequency of PD-1+ T cells, which may be decreased after eradication by DAAs. DAAs altered the immune responses of patients to HCC by decreasing the frequency of PD-1-expressing CD4+ and CD8+ T cells.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C Crónica , Hepatitis C , Neoplasias Hepáticas , Antivirales/farmacología , Antivirales/uso terapéutico , Carcinoma Hepatocelular/patología , Antígeno HLA-A24/uso terapéutico , Hepacivirus , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Inmunidad , Neoplasias Hepáticas/patología , Receptor de Muerte Celular Programada 1
13.
Pharm Biol ; 60(1): 1038-1046, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35634656

RESUMEN

CONTEXT: Panax ginseng C. A. Meyer (Araliaceae) is a famous Asian medicine. Ginsenoside Rc is a component isolated from Panax ginseng. OBJECTIVE: This study evaluates the effect of ginsenoside Rc on myocardial ischaemic injury. MATERIALS AND METHODS: Male Swiss mice were subcutaneously injected with 50 mg/kg isoproterenol once a day for three days. Ginsenoside Rc (10, 20, or 40 mg/kg) was intragastrically administered 1 h after isoproterenol injection. The mice in the control group were subcutaneously injected with normal saline and intragastrically given 0.5% CMC-Na. CK-MB and troponin T were assayed. Histopathological examination of myocardium was conducted. The expression of Nrf2, GCLC, GCLM and HO-1 in heart tissues was evaluated by Western blot. RESULTS: In myocardial ischaemic mice, ginsenoside Rc reduced the levels of CK-MB (197.1 ± 15.7, 189.9 ± 19.0, 184.0 ± 14.4 vs. 221.6 ± 27.9) and troponin T (10.3 ± 1.7, 9.5 ± 1.3, 8.7 ± 1.7 vs. 13.4 ± 2.4). Ginsenoside Rc attenuated the necrosis and inflammatory cells infiltration in myocardium. Furthermore, ginsenoside Rc not only decreased the contents of MDA, TNF-α but also increased GSH level in the heart tissues. The expression of Nrf2, GCLC, GCLM and HO-1 was significantly increased in the animals treated with ginsenoside Rc. ML385, an Nrf2 inhibitor, blocked partially the ginsenoside Rc-mediated cardioprotective effect. Ginsenoside Rc attenuated myocardial ischaemic injury in mice, which may be, in part, through its antioxidative and anti-inflammatory effects. CONCLUSIONS: This study indicated that ginsenoside Rc might be a novel candidate for treatment of myocardial ischaemia.


Asunto(s)
Antioxidantes , Panax , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Ginsenósidos , Isoproterenol , Masculino , Ratones , Factor 2 Relacionado con NF-E2/metabolismo , Panax/metabolismo , Troponina T
14.
Angew Chem Int Ed Engl ; 61(9): e202112966, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-34931421

RESUMEN

Syndioselective polymerization of unprotected polar styrenes has achieved great success via specially designed catalysts and the establishment of "self-assisted" theory. In contrast, isospecific polymerization of polar styrenes has remained less explored. Herein, we present new racemic ansa-bis(benz[e]indenyl) rare-earth metal complexes and their high activity and perfect isoselectivity (mmmm>99 %) for the polymerization of unmasked polar styrenes without any activators. Moreover, the copolymerizations of para- and meta-methoxystyrenes with styrene give gradient and random copolymers, respectively. The insertion rate of polar monomers could be readily tuned in the range of 0-100 mol % by changing their loading ratios. The resultant isotactic polar polystyrenes are quantitatively transformed into hydroxyl or methylsulfonyl polystyrenes with high Tg s. DFT calculations reveal the isospecific mechanism.

15.
Neuroradiology ; 63(5): 685-693, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32997164

RESUMEN

PURPOSE: Comprehensive understanding glioma metabolic characters is of great help for patient management. We aimed to compare amide proton transfer imaging (APTw) and magnetization transfer imaging (MT) in predicting glioma malignancy and reflecting tumor proliferation. METHODS: Thirty low-grade gliomas (LGGs) and 39 high-grade gliomas (HGGs) were prospectively included, of which 58 samples Ki-67 levels were quantified. Anatomical MRI, APTw, and MT were scanned, and magnetization transfer ratio (MTR) and asymmetric magnetic transfer ratio at 3.5 ppm (MTRasym(3.5ppm)) were calculated. ROIs were semi-automatically drawn with ImageJ, from which histogram features, including 5th, 25th, 50th, mean, 70th, 90th, and 95th percentiles were extracted. The independent t test was used to test differences in LGGs and HGGs, and correlations between histogram features and tumor grades, Ki-67 were revealed by Spearman's rank or Pearson's correlation analysis. RESULTS: The maximum correlation coefficient (R) values of APTw were 0.526 (p < 0.001) with tumor grades and 0.397 (p < 0.001) with Ki-67 at 90th percentiles, while only 5th and 25th percentiles of MT significantly correlated with tumor grades. Moreover, APTw features were significantly different in LGGs and HGGs, except 5th percentile. The most significantly different feature was 95th percentile, providing the excellent AUC of 0.808. However, the best feature in MTR was 5th percentiles with AUC of 0.703. Combing 5th and 95th of APTw achieved highest AUC Of 0.837. CONCLUSIONS: Both APTw and MT provide quantitative information for tumor metabolite imaging. However, APTw supplys more specific information in reflecting glioma biological behaviors than MT, and well differentiates glioma malignancy.


Asunto(s)
Neoplasias Encefálicas , Glioma , Amidas , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Protones
16.
Med Sci Monit ; 27: e930025, 2021 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-34003815

RESUMEN

BACKGROUND Aberrant DNA methylation is an important biological regulatory mechanism in malignant tumors. However, it remains underutilized for establishing prognostic models for triple-negative breast cancer (TNBC). MATERIAL AND METHODS Methylation data and expression data downloaded from The Cancer Genome Atlas (TCGA) were used to identify differentially methylated sites (DMSs). The prognosis-related DMSs were selected by univariate Cox regression analysis. Functional enrichment was analyzed using DAVID. A protein-protein interaction (PPI) network was constructed using STRING. Finally, a methylation-based prognostic signature was constructed using LASSO method and further validated in 2 validation cohorts. RESULTS Firstly, we identified 743 DMSs corresponding to 332 genes, including 357 hypermethylated sites and 386 hypomethylated sites. Furthermore, we selected 103 prognosis-related DMSs by univariate Cox regression. Using a LASSO algorithm, we established a 5-DMSs prognostic signature in TCGA-TNBC cohort, which could classify TNBC patients with significant survival difference (log-rank p=4.97E-03). Patients in the high-risk group had shorter overall survival than patients in the low-risk group. The excellent performance was validated in GSE78754 (HR=2.42, 95%CI: 1.27-4.59, log-rank P=0.0055). Moreover, for disease-free survival, the prognostic performance was verified in GSE141441 (HR=2.09, 95%CI: 1.28-3.44, log-rank P=0.0027). Multivariate Cox regression analysis indicated that the 5-DMSs signature could serve as an independent risk factor. CONCLUSIONS We constructed a 5-DMSs signature with excellent performance for the prediction of disease-free survival and overall survival, providing a guide for clinicians in directing personalized therapeutic regimen selection of TNBC patients.


Asunto(s)
Metilación de ADN/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Estudios de Cohortes , Supervivencia sin Enfermedad , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Persona de Mediana Edad , Pronóstico , Mapas de Interacción de Proteínas/genética
17.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34681932

RESUMEN

Pentatricopeptide repeat (PPR) proteins form a large protein family in land plants, with hundreds of different members in angiosperms. In the last decade, a number of studies have shown that PPR proteins are sequence-specific RNA-binding proteins involved in multiple aspects of plant organellar RNA processing, and perform numerous functions in plants throughout their life cycle. Recently, computational and structural studies have provided new insights into the working mechanisms of PPR proteins in RNA recognition and cytidine deamination. In this review, we summarized the research progress on the functions of PPR proteins in plant growth and development, with a particular focus on their effects on cytoplasmic male sterility, stress responses, and seed development. We also documented the molecular mechanisms of PPR proteins in mediating RNA processing in plant mitochondria and chloroplasts.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Desarrollo de la Planta , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteínas de Plantas/genética
18.
FASEB J ; 33(2): 1695-1710, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30226809

RESUMEN

Mesenchymal stem cells (MSCs) have been reported to exert therapeutic effects on immunoregulation, tissue repair, and regeneration from the bench to the bedside. Increasing evidence demonstrates that extracellular vesicles (EVs) derived from MSCs could contribute to these effects and are considered as a potential replacement for stem cell-based therapies. However, the efficacy and underlying mechanisms of EV-based treatment in hepatic ischemia-reperfusion injury (IRI) remain unclear. Here, we demonstrated that human umbilical cord MSC-EVs (huc-MSC-EVs) could protect against IRI-induced hepatic apoptosis by reducing the infiltration of neutrophils and alleviating oxidative stress in hepatic tissue in vivo. Meanwhile, huc-MSC-EVs reduced the respiratory burst of neutrophils and prevented hepatocytes from oxidative stress-induced cell death in vitro. Interestingly, we found that the mitochondria-located antioxidant enzyme, manganese superoxide dismutase (MnSOD), was encapsulated in huc-MSC-EVs and reduced oxidative stress in the hepatic IRI model. Knockdown of MnSOD in huc-MSCs decreased the level of MnSOD in huc-MSC-EVs and attenuated the antiapoptotic and antioxidant capacities of huc-MSC-EVs, which could be partially rescued by MnSOD mimetic manganese (III) 5,10,15,20-tetrakis (4-benzoic acid) porphyrin (MnTBAP). In summary, these findings provide new clues to reveal the therapeutic effects of huc-MSC-EVs on hepatic IRI and evaluate their preclinical application.-Yao, J., Zheng, J., Cai, J., Zeng, K., Zhou, C., Zhang, J., Li, S., Li, H., Chen, L., He, L., Chen, H., Fu, H., Zhang, Q., Chen, G., Yang, Y., Zhang, Y. Extracellular vesicles derived from human umbilical cord mesenchymal stem cells alleviate rat hepatic ischemia-reperfusion injury by suppressing oxidative stress and neutrophil inflammatory response.


Asunto(s)
Vesículas Extracelulares/metabolismo , Inflamación/metabolismo , Hígado/irrigación sanguínea , Células Madre Mesenquimatosas/citología , Neutrófilos/metabolismo , Estrés Oxidativo , Daño por Reperfusión/prevención & control , Cordón Umbilical/citología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Hígado/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Estallido Respiratorio
19.
Macromol Rapid Commun ; 41(10): e2000038, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32285525

RESUMEN

Streoregular poly(vinyl alcohol) is hard to obtain because vinyl alcohol is unstable relative to its tautomer acetaldehyde, and the monomer precursor vinyl ester is poisonous to the coordination catalyst. Herein, the coordination polymerization of 2-vinyl-2,1-borazanaphthalene (BN2VN) is reported by the linked or unlinked half-sandwich ligands attached scandium precursors ((FluSiMe3 )Sc(CH2 SiMe3 )2 (THF) (THF = tetrahydrofuran, 1), (FluCH2 CH2 -NHC-R)Sc(CH2 SiMe3 )2 (THF) (R = mesityl 2, i Pr 3, Me 4), and (FluCH2 Py)Sc(CH2 SiMe3 )2 (5) for the first time. Among these precursors, complex 5 converts 600 equivalents of BN2VN into polymer within 5 min to reach an activity as high as 8.99 × 105 g molSc -1 h-1 . The resultant products show excellent syndiotacticity and melting temperatures above 300 °C, which can be transferred to syndiotactic poly(vinyl alcohol) with 90% rr triad content by postpolymerization oxidation.


Asunto(s)
Naftalenos/química , Alcohol Polivinílico/síntesis química , Complejos de Coordinación/química , Estructura Molecular , Polimerizacion , Alcohol Polivinílico/química , Escandio/química , Estereoisomerismo
20.
Angew Chem Int Ed Engl ; 59(11): 4324-4328, 2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-31916646

RESUMEN

The chain-transfer reaction is rather important in coordination polymerization regarding catalytic efficiency, adjustment of molecular weight, and control of chain structure. To date, chain transfer to H2 and Al, Mg, and Zn alkyl compounds and ß-H elimination are the commonly encountered modes. Now a novel chain transfer to toluene is reported. By introducing fluorine atoms into the ß-diketimine ligands, an inert catalytic system for styrene (St) coordination polymerization was transferred into the highly active one. The activity increased with an increase in the number of fluorines in the ligands. Surprisingly, the molecular weights of resultant polystyrenes are very low (Mn =2000-6600 Da) despite of St loadings, corresponding up to 121 chains per active species. The mechanisms were investigated by DFT simulation, MALDI-TOF MS, isotope tracing experiment and 2D NMR spectrum analyses, which revealed that the fluorine activated the polymerization and directed chain transfer to toluene.

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