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1.
Plant Physiol ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276362

RESUMEN

Verticillium wilt (VW) caused by Verticillium dahliae (V. dahliae) is one of the most destructive diseases in cotton (Gossypium spp.). Histone acetylation plays critical roles in plant development and adaptive responses to biotic and abiotic stresses. However, the relevance of histone acetylation in cotton VW resistance remains largely unclear. Here, we identified Histone Deacetylase 5 (GhHDA5) from upland cotton (Gossypium hirsutum L.), as a negative regulator of VW resistance. GhHDA5 expression was responsive to V. dahliae infection. Silencing GhHDA5 in upland cotton led to improved resistance to V. dahliae, while heterologous expression of GhHDA5 in Arabidopsis (Arabidopsis thaliana) compromised V. dahliae tolerance. GhHDA5 repressed the expression of several lignin biosynthesis-related genes, such as 4-coumarate: CoA ligase gene Gh4CL3 and ferulate 5-hydroxylase gene GhF5H, through reducing the acetylation level of Histone H3 Lysine 9 and 14 (H3K9K14ac) at their promoter regions, thereby resulting in an increased deposition of lignin, especially S monomers, in the GhHDA5-silenced cotton plants. The silencing of GhF5H impaired cotton VW tolerance. Additionally, the silencing of GhHDA5 also promoted the production of reactive oxygen species (ROS), elevated the expression of several pathogenesis-related genes (PRs), and altered the content and signaling of the phytohormones salicylic acid (SA), jasmonic acid (JA) and strigolactones (SLs) after V. dahliae infection. Taken together, our findings suggest that GhHDA5 negatively regulates cotton VW resistance through modulating disease-induced lignification and the ROS- and phytohormone-mediated defense response.

2.
J Exp Bot ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303008

RESUMEN

Anthocyanins, a group of flavonoids, play diverse roles in plant growth and environmental adaptation. The biosynthesis and accumulation of anthocyanin are regulated by environmental cues, such as high light. However, the precise mechanism underlying anthocyanin biosynthesis under high light conditions remains largely unclear. Here, we report that the R3-MYB repressor MYB-LIKE 2 (MYBL2) negatively regulates high light-induced anthocyanin biosynthesis by repressing two R2R3-MYB activators, PRODUCTION OF ANTHOCYANIN PIGMENT 1 (PAP1) and PAP2, which are core components of the MYB-bHLH-WD40 (MBW) complex. We found that MYBL2 interacts with PAP1/2 and reduces their transcriptional activation activities, thus disrupting the expression of key genes involved in anthocyanin biosynthesis, such as DIHYDROFLAVONOL 4-REDUCTASE (DFR) and TRANSPARENT TESTA 19 (TT19). Additionally, MYBL2 attenuates the transcriptional activation of PAP1 on its own expression, but not PAP2. Conversely, PAP1 collaborates with TT8, a bHLH member of the MBW complex, to activate MYBL2 transcription when excessive anthocyanins are accumulated. Taken together, our findings reveal a negative feedback regulatory module composed of MYBL2 and PAP1 that fine-tunes high light-induced anthocyanin biosynthesis through modulating MBW complex assembly.

3.
Sensors (Basel) ; 24(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39275466

RESUMEN

China's rail transit system is developing rapidly, but achieving seamless high-precision localization of trains throughout the entire route in closed environments such as tunnels and culverts still faces significant challenges. Traditional localization technologies cannot meet current demands, and the present paper proposes an autonomous localization method for trains based on pulse observation in a tunnel environment. First, the Letts criterion is used to eliminate abnormal gyro data, the CEEMDAN method is employed for signal decomposition, and the decomposed signals are classified using the continuous mean square error and norm method. Noise reduction is performed using forward linear filtering and dynamic threshold filtering, respectively, maximizing the retention of its effective signal components. A SINS/OD integrated localization model is established, and an observation equation is constructed based on velocity matching, resulting in an 18-dimensional complex state space model. Finally, the EM algorithm is used to address Non-Line-Of-Sight and multipath effect errors. The optimized model is then applied in the Kalman filter to better adapt to the system's observation conditions. By dynamically adjusting the noise covariance, the localization system can continue to maintain continuous high-precision position information output in a tunnel environment.

4.
Mol Ther ; 30(1): 244-255, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34687846

RESUMEN

Cas12a is an RNA-guided endonuclease that has been widely used for convenient multiplex gene editing with low off-target effects. To minimize off-targeting in gene editing, we engineered a variant of LbCas12a (termed Lb-K538R) with more stringent PAM recognition, lower off-targeting capability, and similar editing efficiency in vivo compared with LbCas12a. We also demonstrated that Lb2Cas12a from Lachnospiraceae bacterium MA2020 has extensive gene-editing activities in mammalian cells. Similar to Lb-K538R, the designed Lb2Cas12a variant (termed Lb2-K518R) not only had a more stringent PAM sequence change from YYN to TYN (Y is T or C, N is A, T, C, or G), but also displayed lower off-target effects, thereby enabling more potential target site selections with low off-targeting than the common TTTV (V is A, G, or C) PAM. To determine whether this type of mutation at the homologous position had similar effects in other Cas12a, As-K548R was evaluated. Based on the results of the genome-wide off-target test, As-K548R displayed lower off-target effects. Collectively, our findings indicate that the Cas proteins could be designed to be stringent in PAM recognition to reduce their off-target effects, which suggests a promising and practical approach for minimizing off-targets effects in genome editing.


Asunto(s)
Proteínas Asociadas a CRISPR , Sistemas CRISPR-Cas , Animales , Proteínas Asociadas a CRISPR/genética , Proteínas Asociadas a CRISPR/metabolismo , Endonucleasas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Mamíferos , ARN/genética
5.
Artif Organs ; 45(8): 866-880, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33432632

RESUMEN

Neurological dysfunction commonly occurs after cardiac surgery with deep hypothermic circulatory arrest (DHCA). The mechanisms underlying DHCA-associated brain injury remain poorly understood. This study determined the changes in expression profiles of circular RNAs (circRNAs) in the hippocampus in rats that underwent DHCA, with an attempt to explore the potential role of circRNAs in the brain injury associated with DHCA. Adult male Sprague Dawley rats were subjected to cardiopulmonary bypass with DHCA. Brain injury was evaluated by neurological severity scores and histological as well as transmission electron microscope examinations. The expression profiles of circRNAs in the hippocampal tissues were screened by microarray. Quantitative real-time PCR (RT-qPCR) was used to validate the reliability of the microarray results. Bioinformatic algorithms were applied to construct a competing endogenous RNA (ceRNA) network, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to explore the potential biological roles of the circRNAs. Out of 14 145 circRNAs screened, 56 were differentially expressed in the hippocampus between the DHCA and sham-operated rats, including 30 upregulated and 26 downregulated circRNAs. The expression changes of six selected circRNAs (upregulated: rno_circRNA_011190, rno_circRNA_012988, rno_circRNA_000544; downregulated: rno_circRNA_010393, rno_circRNA_012043, rno_circRNA_015149) were further confirmed by RT-qPCR. Bioinformatics analysis showed the enrichment of these confirmed circRNAs and their potential target mRNAs in several KEGG pathways including histidine metabolism, adipocytokine signaling, and cAMP signaling. By revealing the change expression profiles of circRNAs in the brain after DHCA, this study indicates possible involvements of these dysregulated circRNAs in brain injury and suggests a potential of targeting circRNAs for prevention and treatment of neurological dysfunction associated with DHCA.


Asunto(s)
Paro Circulatorio Inducido por Hipotermia Profunda , Hipocampo/metabolismo , ARN Circular/metabolismo , Algoritmos , Animales , Biología Computacional/métodos , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa
6.
J Cell Physiol ; 234(9): 15607-15618, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30779109

RESUMEN

Bladder cancer (BC) is one of the most common neoplastic diseases worldwide. With the highest recurrence rate among all cancers, treatment of BC only improved a little in the last 30 years. Available biomarkers are not sensitive enough for the diagnosis of BC, whereas the standard diagnostic method, cystoscopy, is an invasive test and expensive. Hence, seeking new biomarkers of BC is urgent and challenging. With that order, we screened the overlapped differentially expressed genes (DEGs) of GSE13507 and TCGA BLCA datasets. Subsequent protein-protein interactions network analysis recognized the hub genes among these DEGs. Further functional analysis including Gene Ontology and KEGG pathway analysis and gene set enrichment analysis were processed to investigate the role of these genes and potential underlying mechanisms in BC. Kaplan-Meier analysis and Cox hazard ratio analysis were carried out to clarify the diagnostic and prognostic role of these genes. In conclusion, our present study demonstrated that ACTA2, CDC20, MYH11, TGFB3, TPM1, VIM, and DCN are all potential diagnostic biomarkers for BC. And may also be potential treatment targets for clinical implication in the future.

7.
J Sex Med ; 16(4): 522-530, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30935469

RESUMEN

INTRODUCTION: Although guidelines from the American Urological Association and European Association of Urology do not consider surgical treatment for premature ejaculation (PE), the use of selective dorsal neurectomy (SDN) has increased for many years in Asian countries. AIM: To evaluate anatomic basis and clinical effect of SDN in patients with PE in mainland China. METHODS: All of the patients included in the study had redundant foreskin, and they were assigned to 2 groups: group 1, composed of 46 patients with redundant foreskin, and group 2, composed of 96 patients with redundant foreskin and PE. The patients in group 2 were further randomly classified into group 2a (n = 48) and group 2b (n = 48). MAIN OUTCOME MEASURES: The number of dorsal penile nerve branches were compared among group 1, group 2a, and group 2b. Preoperative and postoperative intravaginal ejaculatory latency time (IELT), 5-item version of the International Index of Erectile Function, Premature Ejaculation Diagnostic Tool, and postoperative complications were compared between group 2a and group 2b. RESULTS: The patients in group 2 had a greater number of dorsal penile nerve branches of 1-2-mm-diameter, ≥2-mm-diameter, and total branches than group 1. The postoperative IELT of group 2a (257.7 ± 205.7 seconds) was longer than that of group 2b (49.3 ± 26.1 seconds). Group 2a had more ejaculation controllability and lower Premature Ejaculation Diagnostic Tool scores than group 2b after the surgery (P < .001). We did not observe permanent numbness in glans, wound infection, or hematoma in any patients. CLINICAL IMPLICATION: SDN is an effective treatment for lifelong PE patients who had poor response to medicine or refused oral medication. STRENGTH & LIMITATIONS: This study has some strengths. First, the study made a comprehensive comparison based on both the numbers of dorsal penile nerve branches and the effect. Second, a randomized controlled trial design was used for the evaluation of SDN. It also possesses a limitation-we did not determine how many dorsal nerves should be selectively resected for each person to achieve optimal IELT prolongation. CONCLUSION: The dorsal penile nerve branches of patients with lifelong PE are more and thicker than those without lifelong PE, and SDN is effective in improving lifelong PE by IELT prolongation and ejaculation controllability, with few postoperative complications. Liu Q, Li S, Zhang Y, et al. Anatomic Basis and Clinical Effect of Selective Dorsal Neurectomy for Patients with Lifelong Premature Ejaculation: A Randomized Controlled Trial. J Sex Med 2019;16:522-530.


Asunto(s)
Desnervación , Pene/cirugía , Eyaculación Prematura/cirugía , Adulto , China , Eyaculación/fisiología , Humanos , Masculino , Pene/fisiopatología , Eyaculación Prematura/fisiopatología , Resultado del Tratamiento , Adulto Joven
8.
J Sex Med ; 15(8): 1073-1082, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29960891

RESUMEN

BACKGROUND: Some studies have reported that exposure to depression increases the risk of erectile dysfunction (ED), whereas others have observed no association. Moreover, additional studies have reported that exposure to ED increases the risk of depression. AIM: To identify and quantitatively synthesize all studies evaluating the association between ED and depression and to explore factors that may explain differences in the observed association. METHODS: We conducted a systematic review and meta-analysis. We searched Medline, Ovid Embase, and the Cochrane Library through October 2017 for studies that had evaluated the association between ED and depression. Studies were included in accordance with Patient Population or Problem, Intervention, Comparison, Outcomes, and Setting (PICOS) inclusion criteria. OUTCOMES: The odds ratio (OR) was regarded as the effect size, and the heterogeneity across studies was assessed using the I2 statistic. RESULTS: We identified 49 eligible publications. The pooled OR for studies evaluating depression exposure and risk of ED was 1.39 (95% CI: 1.35-1.42; n = 46 publications with 48 studies). Although we observed large heterogeneity (I2 = 93.6%), subgroup analysis indicated that it may have been as a result of variations in study design, comorbidities, ED assessment, depression assessment, the source of the original effect size, etc. No significant publication bias was observed (P = .315), and the overall effect size did not change by excluding any single study. The pooled OR for studies evaluating ED exposure and risk of depression was 2.92 (95% CI: 2.37-3.60; n = 5 publications with 6 studies). No significant heterogeneity (P < .257, I2 = 23.5%) or publication bias (P = .260) was observed. CLINICAL IMPLICATIONS: Patients reporting ED should be routinely screened for depression, whereas patients presenting with symptoms of depression should be routinely assessed for ED. STRENGTHS AND LIMITATIONS: There are several strengths to this study. First, evaluations of the association between ED and depression are timely and relevant for clinicians, policymakers, and patients. Second, we intentionally conducted 2 meta-analyses on the association, allowing us to include all potentially relevant studies. However, our study also possesses some limitations. First, the OR is a measure of association that only reveals whether an association is present. Thus, this study was unable to determine the direction of causality between ED and depression. Second, the high heterogeneity among studies makes it difficult to generalize the conclusions. CONCLUSION: This study demonstrates an association between depression and ED. Policymakers, clinicians and patients should attend to the association between depression and ED. Liu Q, Zhang Y, Wang J, et al. Erectile dysfunction and depression: A systematic review and meta-analysis. J Sex Med 2018;15:1073-1082.


Asunto(s)
Depresión/epidemiología , Disfunción Eréctil/epidemiología , Depresión/diagnóstico , Disfunción Eréctil/diagnóstico , Humanos , Masculino , Oportunidad Relativa
9.
Eur Radiol ; 28(9): 3789-3800, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29600478

RESUMEN

OBJECTIVES: To investigate the cerebral structural changes related to venous erectile dysfunction (VED) and the relationship of these changes to clinical symptoms and disorder duration and distinguish patients with VED from healthy controls using a machine learning classification. METHODS: 45 VED patients and 50 healthy controls were included. Voxel-based morphometry (VBM), tract-based spatial statistics (TBSS) and correlation analyses of VED patients and clinical variables were performed. The machine learning classification method was adopted to confirm its effectiveness in distinguishing VED patients from healthy controls. RESULTS: Compared to healthy control subjects, VED patients showed significantly decreased cortical volumes in the left postcentral gyrus and precentral gyrus, while only the right middle temporal gyrus showed a significant increase in cortical volume. Increased axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) values were observed in widespread brain regions. Certain regions of these alterations related to VED patients showed significant correlations with clinical symptoms and disorder durations. Machine learning analyses discriminated patients from controls with overall accuracy 96.7%, sensitivity 93.3% and specificity 99.0%. CONCLUSIONS: Cortical volume and white matter (WM) microstructural changes were observed in VED patients, and showed significant correlations with clinical symptoms and dysfunction durations. Various DTI-derived indices of some brain regions could be regarded as reliable discriminating features between VED patients and healthy control subjects, as shown by machine learning analyses. KEY POINTS: • Multimodal magnetic resonance imaging helps clinicians to assess patients with VED. • VED patients show cerebral structural alterations related to their clinical symptoms. • Machine learning analyses discriminated VED patients from controls with an excellent performance. • Machine learning classification provided a preliminary demonstration of DTI's clinical use.


Asunto(s)
Encefalopatías/diagnóstico por imagen , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Disfunción Eréctil/diagnóstico , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Adulto , Biomarcadores , Encefalopatías/complicaciones , Encefalopatías/patología , Imagen de Difusión Tensora/métodos , Disfunción Eréctil/complicaciones , Humanos , Masculino , Imagen Multimodal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Mol Biotechnol ; 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37919618

RESUMEN

Deep hypothermic circulatory arrest (DHCA) can protect the brain during cardiac and aortic surgery by cooling the body, but meanwhile, temporary or permanent brain injury may arise. H2S protects neurons and the central nervous system, especially from secondary neuronal injury. We aim to unveil part of the mechanism of H2S's attenuating effect on brain injury induced by DHCA by exploring crucial target genes, and further promote the clinical application of H2S in DHCA. Nine SD rats were utilized to provide histological and microarray samples, and further the differential expression analysis. Then we conducted GO and KEGG pathway enrichment analyses on candidate genes. The protein-protein interaction (PPI) networks were performed by STRING and GeneMANIA. Crucial target genes' expression was validated by qRT-PCR and western blot. Histological study proved DHCA's damaging effect and H2S's repairing effect on brain. Next, we got 477 candidate genes by analyzing differentially expressed genes. The candidate genes were enriched in 303 GO terms and 28 KEGG pathways. Then nine genes were selected as crucial target genes. The function prediction by GeneMANIA suggested their close relation to immunity. FGF2 was identified as the crucial gene. FGF2 plays a vital role in the pathway when H2S attenuates brain injury after DHCA. Our research provides more information for understanding the mechanism of H2S attenuating brain injury after DHCA. We infer the process might probably be closely associated with immunity.

11.
J Vis Exp ; (192)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36847364

RESUMEN

The goal of this article is to present the application of a 24 G cannula and 3-0 polypropylene suture as a simple method for the exploration of the vas deferens. During the exploration of the vas deferens, a 24 G cannula needle was used to puncture it. The fluid in the smear confirmed the presence of sperm, to determine whether or not there was concomitant obstruction at the junction of the epididymis and the vas deferens. Then, a 3-0 polypropylene suture (this suture specification has the advantages of a smooth surface, robust quality, and can be passed through a 24 G cannula needle) was passed through the cannula needle to probe the location of the obstructed site. With this technique, exploration of the vas deferens could be more targeted and accurate.


Asunto(s)
Saltamontes , Yodo , Animales , Masculino , Conducto Deferente/cirugía , Polipropilenos , Cánula , Semen , Epidídimo , Suturas
12.
J Clin Med ; 12(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36769462

RESUMEN

Neurological dysfunction is a common complication of deep hypothermic circulatory arrest (DHCA). Endoplasmic reticulum (ER) stress plays a role in neuronal ischemia-reperfusion injury; however, it is unknown whether it contributes to DHCA-induced brain injury. Here, we aimed to investigate the role of ER stress in a rat DHCA model and cell hypothermic oxygen-glucose deprivation reoxygenation (OGD/R) model. ER stress and apoptosis-related protein expression were identified using Western blot analysis. Cell counting assay-8 and flow cytometry were used to determine cell viability and apoptosis, respectively. Brain injury was evaluated using modified neurological severity scores, whereas brain injury markers were detected through histological examinations and immunoassays. We observed significant ER stress molecule upregulation in the DHCA rat hippocampus and in hypothermic OGD/R PC-12 cells. In vivo and in vitro experiments showed that ER stress or activating transcription factor 6 (ATF6) inhibition alleviated rat DHCA-induced brain injury, increased cell viability, and decreased apoptosis accompanied by C/EBP homologous protein (CHOP). ER stress is involved in DHCA-induced brain injury, and the inhibition of the ATF6 branch of ER stress may ameliorate this injury by inhibiting CHOP-mediated apoptosis. This study establishes a scientific foundation for identifying new therapeutic targets for perioperative brain protection in clinical DHCA.

13.
Brain Sci ; 13(3)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36979335

RESUMEN

OBJECTIVES: Postoperative neurological deficits remain a challenge in cardiac surgery employing deep hypothermic circulatory arrest (DHCA). This study aimed to investigate the effect of WIN55, 212-2, a cannabinoid agonist, on brain injury in a rat model of DHCA. METHODS: Twenty-four male Sprague Dawley rats were randomly divided into three groups: a control group (which underwent cardiopulmonary bypass (CPB) only), a DHCA group (CPB with DHCA), and a WIN group (WIN55, 212-2 pretreatment before CPB with DHCA). Histopathological changes in the brain were evaluated by hematoxylin-eosin staining. Plasma levels of superoxide dismutase (SOD) and proinflammatory cytokines including interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-a) were determined using an enzyme-linked immunosorbent assay (ELISA). The expression of SOD in the hippocampus was detected by Western blot and immunofluorescence staining. Levels of apoptotic-related protein caspase-3 and type 1 cannabinoid receptor (CB1R) in the hippocampus were evaluated by Western blot. RESULTS: WIN55, 212-2 administration attenuated histopathological injury of the hippocampus in rats undergoing DHCA, associated with lowered levels of IL-1ß, IL-6, and TNF-α (p < 0.05, p < 0.001, and p < 0.01, vs. DHCA, respectively) and an increased level of SOD (p < 0.05 vs. DHCA). WIN55, 212-2 treatment also increased the content of SOD in the hippocampus. The protein expression of caspase-3 was downregulated and the expression of CB1R was upregulated in the hippocampus by WIN55, 212-2. CONCLUSIONS: the administration of WIN55, 212-2 alleviates hippocampal injury induced by DHCA in rats by regulating intrinsic inflammatory and oxidative stress responses through a CB1R-dependent mechanism.

14.
Curr Med Sci ; 43(2): 324-328, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36892787

RESUMEN

OBJECTIVE: This study aimed to investigate the effect of penile selective dorsal neurectomy (SDN) on erectile function in rats. METHODS: Twelve adult male Sprague-Dawley rats (15 weeks old) were divided into three groups (n=4 per group): in control group, rats received no treatment; in sham group, rats underwent a sham operation; in SDN group, rats underwent SDN with half of the dorsal penile nerve severed. The mating test was performed, and the intracavernous pressure (ICP) assessed six weeks after the surgical treatment. RESULTS: At postoperative six weeks, the mating test revealed no significant difference in mounting latency and mounting frequency among the three groups (P>0.05), while the ejaculation latency (EL) was significantly longer and ejaculation frequency (EF) lower in the SDN group than in the control and sham groups (P<0.05). There were no significant differences in preoperative and postoperative ICP and ICP/mean arterial blood pressure (MAP) among the three groups (P>0.05). CONCLUSION: SDN does not adversely affect the erectile function and sexual desire of rats, and at the same time it can reduce EL and EF, providing an application basis for SDN in the clinical treatment of premature ejaculation.


Asunto(s)
Disfunción Eréctil , Humanos , Ratas , Masculino , Animales , Disfunción Eréctil/etiología , Disfunción Eréctil/cirugía , Disfunción Eréctil/tratamiento farmacológico , Ratas Sprague-Dawley , Erección Peniana/fisiología , Pene/cirugía , Pene/inervación , Desnervación
15.
Materials (Basel) ; 16(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36614666

RESUMEN

Graphene is a two-dimensional nanomaterial with excellent mechanical, electrical and thermal properties. The application of graphene in cement-based materials has good prospects. However, the mechanical properties of cement-based materials are difficult to be significantly enhanced by ordinary graphene nanoplates. In this paper, nitrogen-doped graphene is first reported as an additive with dosages of 0.01, 0.02, 0.03, 0.04 and 0.05 wt.%, respectively, to prepare iron ore tailings-based cementitious composites. The iron ore tailings-based cementitious composite with 0.02 wt.% graphene shows an extremely high flexural strength of 15.05 MPa at 3 days, which is 134.4% higher than that of the iron ore tailings-based cementitious composite without graphene. The effects of graphene content and curing age on the flexural strength and microstructure of iron ore tailings-based cementitious composites were studied. In particular, the scanning electron microscope was adopted to observe the micromorphology of the composites. It is helpful to understand the graphene reinforcement mechanism for the high early flexural strength of iron ore tailings-based cementitious composites. By altering the morphology of iron ore tailings-based cementitious composites, graphene plays two roles in the composites. One role is to connect C-(A)-S-H gels, ettringite and other hydrated crystals to construct a three-dimensional structure. The other is to attract iron ore tailings distributed on its platform to enhance its flexural strength properties. These findings provide favorable guidance for the performance enhancement and mechanism replenishment of graphene-reinforced cementitious composites.

16.
Environ Technol ; 43(21): 3283-3294, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33944689

RESUMEN

In this study, red mud (RM) was modified with titanate coupling agent (triisostearoyl isopropoxy titanate, KR-TTS), and then the modified RM was melted blending with high-density polyethylene (HDPE) to prepare HDPE-based composite. The action mechanism of KR-TTS on the properties of HDPE composites was analysed combining with the movement mode of polyethylene macromolecular chain segments. The entanglement and mechanical interlocking of long alkyl chains of titanate coupling agent and the polyethylene molecular chains occurs in modified RM/HDPE composite, reflected by fracture morphology within tension process. The stronger interface interaction results in a decrease of polyethylene molecular chain segments motion under external loading, externally expressed as higher tensile strength and tensile modulus as well as storage modulus. Meanwhile, KR-TTS imparts modified RM/HDPE composite with higher elongation at break of uniaxial tension and lower damping ratio. The impact strength presents an improvement from 5.62 kJ/m2 of RM/HDPE composite to 6.56 kJ/m2 of modified RM/HDPE composite due to stronger interface strength. And modified RM/HDPE composite appears higher thermal stability, attributed to better particles dispersion and higher interface adhesion. Differential scanning calorimetric analysis shows that with the addition of coupling agent, the melt enthalpy of modified RM/HDPE composite decreases, indicating a decrement in the crystallinity of polyethylene composites (from 70.2% of RM/HDPE to 63.1% of modified RM/HDPE), resulted from the retarded stacking speed of chain segments into the crystal lattice during crystal growth.


Asunto(s)
Polietileno , Polietileno/química , Resistencia a la Tracción
17.
Materials (Basel) ; 15(10)2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35629568

RESUMEN

In this paper, the possibility of applying different welding strategies to overlay an FeCrAl layer against corrosion from heavy liquid metal on a plain plate made of 316L austenitic stainless steel was investigated. This technology could be used in manufacturing the main vessel of CiADS, which may be considered as a more economic and feasible solution than production with the corrosion-resistant FeCrAl alloy directly. The main operational parameters of the laser welding process, including laser power, weld wire feeding speed, diameter of the welding wire, etc., were adjusted correspondingly to the optimized mechanical properties of the welded plate. After performing the standard nuclear-grade bending tests, it can be preliminarily confirmed that the low-power pulse laser with specific operational parameters and an enhanced cooling strategy will be suitable to surface an Fe-10Cr-4Al-RE layer with a thickness of approximately 1 mm on a 40 mm-thick 316L stainless steel plate, thanks to the upgraded mechanical properties incurred by refined grains with a maximum size of around 300 µm in the welded layer.

18.
Front Bioeng Biotechnol ; 10: 1098021, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36588936

RESUMEN

Zymomonas mobilis is a promising microorganism for industrial bioethanol production. However, ethanol produced during fermentation is toxic to Z. mobilis and affects its growth and bioethanol production. Although several reports demonstrated that the RNA-binding protein Hfq in Z. mobilis contributes to the tolerance against multiple lignocellulosic hydrolysate inhibitors, the role of Hfq on ethanol tolerance has not been investigated. In this study, hfq in Z. mobilis was either deleted or overexpressed and their effects on cell growth and ethanol tolerance were examined. Our results demonstrated that hfq overexpression improved ethanol tolerance of Z. mobilis, which is probably due to energy saving by downregulating flagellar biosynthesis and heat stress response proteins, as well as reducing the reactive oxygen species induced by ethanol stress via upregulating the sulfate assimilation and cysteine biosynthesis. To explore proteins potentially interacted with Hfq, the TEV protease mediated Yeast Endoplasmic Reticulum Sequestration Screening system (YESS) was established in Z. mobilis. YESS results suggested that Hfq may modulate the cytoplasmic heat shock response by interacting with the heat shock proteins DnaK and DnaJ to deal with the ethanol inhibition. This study thus not only revealed the underlying mechanism of enhanced ethanol tolerance by hfq overexpression, but also provided an alternative approach to investigate protein-protein interactions in Z. mobilis.

19.
Bioengineered ; 12(1): 555-564, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33517850

RESUMEN

Kidney renal clear cell carcinoma (ccRCC) is a malignant tumor originating from renal tubular epithelium, lncRNAs can regulate the occurrence and development of EMT by targeting EMT transcription factors. We constructed a new survival signature based on EMT-related differentially expressed lncRNAs obtained from the Cancer Genome Atlas (TCGA-KIRC). We first determined 1377 EMT-related lncRNAs, lncRNA AL035661.1 with the largest correlation coefficient and the target gene was PFN2 (cor = 0.843; P= 1.37E-146). Meanwhile, we found an AUC of 0.758 in our signature and we predicted the AUC values of the patients' 1, 2, 3-year survival rate as 0.768, 0.749, and 0.762 in TCGA cohort, respectively. Multivariate COX analysis was performed to determine if risk score was an independent prognostic predictor of OS. The results indicated that our risk score can be an independent predictor for OS (Univariate: HR = 1.350, 95% CI = 1.276-1.428, P< 0.001; Multivariate: HR = 1.295, 95% CI = 1.201-1.396, P< 0.001). We identified novel EMT-related lncRNAs markers for ccRCC prognosis. The underlying mechanism between EMT-related lncRNAs in ccRCC and tumor immunity is still unclear and requires further study.


Asunto(s)
Carcinoma de Células Renales , Transición Epitelial-Mesenquimal/genética , Neoplasias Renales , ARN Largo no Codificante , Transcriptoma/genética , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Minería de Datos , Humanos , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , ARN Largo no Codificante/análisis , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
20.
Materials (Basel) ; 14(8)2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33916954

RESUMEN

China is developing an ADS (Accelerator-Driven System) research device named the China initiative accelerator-driven system (CiADS). When performing a safety analysis of this new proposed design, the core behavior during the steam generator tube rupture (SGTR) accident has to be investigated. The purpose of our research in this paper is to investigate the impact from different heating conditions and inlet steam contents on steam bubble and coolant temperature distributions in ADS fuel assemblies during a postulated SGTR accident by performing necessary computational fluid dynamics (CFD) simulations. In this research, the open source CFD calculation software OpenFOAM, together with the two-phase VOF (Volume of Fluid) model were used to simulate the steam bubble behavior in heavy liquid metal flow. The model was validated with experimental results published in the open literature. Based on our simulation results, it can be noticed that steam bubbles will accumulate at the periphery region of fuel assemblies, and the maximum temperature in fuel assembly will not overwhelm its working limit during the postulated SGTR accident when the steam content at assembly inlet is less than 15%.

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