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1.
Small ; : e2405608, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39428889

RESUMEN

Transition metal nitrides (TMNs) with high theoretical capacity and excellent electrical conductivity have great potential as anode materials for lithium-ion batteries (LIBs), but suffer from poor rate performance due to the slow kinetics. Herein, taking the Fe2N for instance, Co doping is utilized to enhance the work function of Fe2N, which accelerates the charge transfer and strengthens the adsorption of Li+ ions. The Fe2N nanoparticles with various Co dopants are anchoring on the surface of honeycomb porous carbon foam (named Cox-Fe2N@C). Co-doping can enlarge the work function of pristine Fe2N and thereby optimize the charging/discharging kinetics. The work function can be increased from 5.23 eV (pristine Fe2N) to 5.67 eV for Co0.3-Fe2N@C and 5.56 eV for Co0.1-Fe2N@C. As expected, the Co0.1-Fe2N@C electrode exhibits the highest specific capacity (673 mA h g-1 at 100 mA g-1) and remarkable rate capability (375 mA h g-1 at 5 000 mA g-1), outperforming most reported TMNs electrodes. Therefore, this work provides a promising strategy to design and regulate anode materials for high-performance and even commercially available LIBs.

2.
Plant Signal Behav ; 19(1): 2371694, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38916149

RESUMEN

MYB transcription factor is one of the largest families in plants. There are more and more studies on plants responding to abiotic stress through MYB transcription factors, but the mechanism of some family members responding to salt stress is unclear. In this study, physiological and transcriptome techniques were used to analyze the effects of the R2R3-MYB transcription factor AtMYB72 on the growth and development, physiological function, and key gene response of Arabidopsis thaliana. Phenotypic observation showed that the damage of overexpression strain was more serious than that of Col-0 after salt treatment, while the mutant strain showed less salt injury symptoms. Under salt stress, the decrease of chlorophyll content, the degree of photoinhibition of photosystem II (PSII) and photosystem I (PSI) and the degree of oxidative damage of overexpressed lines were significantly higher than those of Col-0. Transcriptome data showed that the number of differentially expressed genes (DEGs) induced by salt stress in overexpressed lines was significantly higher than that in Col-0. GO enrichment analysis showed that the response of AtMYB72 to salt stress was mainly by affecting gene expression in cell wall ectoplast, photosystem I and photosystem II, and other biological processes related to photosynthesis. Compared with Col-0, the overexpression of AtMYB72 under salt stress further inhibited the synthesis of chlorophyll a (Chla) and down-regulated most of the genes related to photosynthesis, which made the photosynthetic system more sensitive to salt stress. AtMYB72 also caused the outbreak of reactive oxygen species and the accumulation of malondialdehyde under salt stress, which decreased the activity and gene expression of key enzymes in SOD, POD, and AsA-GSH cycle, thus destroying the ability of antioxidant system to maintain redox balance. AtMYB72 negatively regulates the accumulation of osmotic regulatory substances such as soluble sugar (SS) and soluble protein (SP) in A. thaliana leaves under salt stress, which enhances the sensitivity of Arabidopsis leaves to salt. To sum up, MYB72 negatively regulates the salt tolerance of A. thaliana by destroying the light energy capture, electron transport, and antioxidant capacity of Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Estrés Oxidativo , Fotosíntesis , Hojas de la Planta , Estrés Salino , Arabidopsis/genética , Arabidopsis/efectos de los fármacos , Arabidopsis/fisiología , Arabidopsis/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Estrés Salino/genética , Estrés Oxidativo/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema I/metabolismo , Clorofila/metabolismo
3.
PLoS One ; 18(6): e0284238, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37267409

RESUMEN

This study investigated the impact of axial load on the dynamic response of reinforced concrete (RC) members to asymmetrical lateral impact loads. A series of asymmetrical-span impact tests were conducted on circular and square RC members with and without Carbon Fiber Reinforced Polymers (CFRP) while varying the axial compression ratios. The impact process was simulated using ABAQUS software, and the time history curves of deflection and impact were measured. The study found that specific impact loads caused bending and shearing failures. The axial compression ratio ranged from 0.05 to 0.13 when the impact curve reached its maximum deflection before the component's impact resistance decreased. Analysis of the impact point and inclined crack location revealed that axial load affects the maximum local concrete. The speed of inclined crack penetration and inclined cracks take longer to form, with weaker resistance to damage to local concrete when the axial compression ratio is between 0.05 and 0.13. When the axial compression ratio is greater than 0.13, inclined cracks form sooner with more brittle and severe damage to the impact point's concrete. The study also identified key parameters affecting the dynamic response of RC members, including impact height, CFRP layer thickness, axial force, and impact location. Thicker CFRP layers in RC can improve impact resistance, especially when the impact location is farther from the center. However, there is a limit to the impact of axial force on this resistance.


Asunto(s)
Compresión de Datos , Polímeros , Fibra de Carbono , Plásticos
4.
Nanoscale Adv ; 5(3): 970-979, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36756530

RESUMEN

Ta2O5 holds great potential for lithium storage due to its high theoretical capacity and long-life cycling. However, it still suffers from an unsatisfactory rate capability because of its low conductivity and significant volume expansion during the charging/discharging process. In this study, a zero-strain strategy was developed to composite Ta2O5 with zero-strain TaC as an anode for lithium-ion batteries (LIBs). The zero-strain TaC, featuring negligible lattice expansion, can alleviate the volume variation of Ta2O5 when cycling, thereby enhancing the rate capacity and long-term cycling stability of the whole electrode. Further, the formation of a heterostructure between Ta2O5 and TaC was confirmed, giving rise to an enhancement in the electrical conductivity and structural stability. As expected, this anode displayed a reversible specific capacity of 395.5 mA h g-1 at 0.5 A g-1 after 500 cycles. Even at an ultrahigh current density of 10 A g-1, the Ta2O5/TaC anode delivered a high capacity of 144 mA h g-1 and superior durability with a low-capacity decay rate of 0.08% per cycle after 1000 cycles. This zero-strain strategy provides a promising avenue for the rational design of anodes, sequentially contributing to the development of high-rate capacity and long cycling LIBs.

5.
Sci Rep ; 12(1): 14793, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042277

RESUMEN

Traffic accidents and derailed train-related incidents have occurred more often than ever in recent years, resulting in some economic damage and casualties. Reinforced concrete (RC) constructions often involve derailed train and vehicle accidents. Rarely are such side collisions studied in previous studies. To do this, high-fidelity simulation-based finite-element (FE) models are created in this paper to accurately simulate the collision of circular RC members with a derailed train. The reinforced concrete member structure is common in high-speed railway stations. The impact energy of the impact body is significant, causing structural member failure. It analyses the dynamic behavior of reinforced concrete members under unequal span impact loads. Numerical implementations of impact issues are discussed from the perspective of geometric, contact, and material properties. The reliability and precision of the ABAQUS code to solve impact issues are verified by comparing failure modes, impact, and deflection time history experimental outputs. By analysing the impact response characteristics, used the control variables to study the failure process and mode (including the characteristics of impact and reaction forces, deflection time history curve, impact force-deflection curve, and bearing reaction force-deflection curve). The reinforcement ratio, impact velocity, concrete strength, and slenderness ratio significantly affect shear crack pattern and development. Changes in impact velocity and slenderness ratio also affect member failure modes.

6.
J Clin Transl Hepatol ; 10(2): 230-237, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35528974

RESUMEN

Background and Aims: We compared lung function parameters in nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD), and examined the association between lung function parameters and fibrosis severity in MAFLD. Methods: In this cross-sectional study, we randomly recruited 2,543 middle-aged individuals from 25 communities across four cities in China during 2016 and 2020. All participants received a health check-up including measurement of anthropometric parameters, biochemical variables, liver ultrasonography, and spirometry. The severity of liver disease was assessed by the fibrosis (FIB)-4 score. Results: The prevalence of MAFLD was 20.4% (n=519) and that of NAFLD was 18.4% (n=469). After adjusting for age, sex, adiposity measures, smoking status, and significant alcohol intake, subjects with MAFLD had a significantly lower predicted forced vital capacity (FVC, 88.27±17.60% vs. 90.82±16.85%, p<0.05) and lower 1 s forced expiratory volume (FEV1, 79.89±17.34 vs. 83.02±16.66%, p<0.05) than those with NAFLD. MAFLD with an increased FIB-4 score was significantly associated with decreased lung function. For each 1-point increase in FIB-4, FVC was diminished by 0.507 (95% CI: -0.840, -0.173, p=0.003), and FEV1 was diminished by 0.439 (95% CI: -0.739, -0.140, p=0.004). The results remained unchanged when the statistical analyses was performed separately for men and women. Conclusions: MAFLD was significantly associated with a greater impairment of lung function parameters than NAFLD.

7.
Front Cell Dev Biol ; 9: 698558, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34336850

RESUMEN

BACKGROUND: Linc00312 is dysregulated in nasopharyngeal carcinoma (NPC) and participates in the initiation and progression of NPC. Our previous studies suggested that linc00312 was able to enhance the sensitivity of NPC cells to irradiation and NPC patients with higher expression of linc00312 was associated with better short-term curative effect and overall survival. The single nucleotide polymorphisms (SNPs) of lncRNAs may influence the disease course and outcome by affecting the expression, secondary structure or function of lncRNAs. However, the role of SNPs in linc00312 on the occurrence and survival of NPC remains unknown. METHODS: We recruited 684 NPC patients and 823 healthy controls to evaluate the association between linc00312 SNPs and NPC susceptibility by using multivariate logistic regression analysis. Kaplan-Meier analysis and Cox proportional hazards regression were applied to assess the effect of linc00312 SNPs on the survival of NPC patients. The relative expression of linc00312 in NPC tissues was determined by real-time PCR. The interaction between linc00312 and mir-411-3p was explored by luciferase reporter assay. In silico prediction of the changes on linc00312 folding structure was conducted by RNAfold WebServer. RESULT: We demonstrated that rs12497104 (G > A) GA genotype carriers had a higher risk than others for suffering from NPC (GA vs GG, OR = 1.437, P = 0.003). Besides, patients with rs12497104 AA genotype showed a poorer overall survival in contrast to GG genotype (AA vs GG, HR = 2.117, P = 0.011). In addition, the heterozygous carriers of rs15734 (G > A) and rs164966 (A > G) were correlated with decreased risk of NPC (GA vs GG, OR = 0.778, P = 0.031; GA vs AA, OR = 0.781, P = 0.033, respectively). We found that the three SNPs might influence the expression of linc00312 in a genotype specific feature. The local centroid secondary structure as well as the minimum free energy of linc00312 were changed following the candidate SNPs alterations. Besides, we revealed that the G to A alteration at rs12497104 disrupted the binding between mir-411-3p and linc00312. CONCLUSION: Our results indicated genetic polymorphisms of linc00312 might serve as potential biomarkers for NPC carcinogenesis and prognosis.

8.
Br J Pharmacol ; 178(8): 1741-1755, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33608889

RESUMEN

RNAi effectors (e.g. siRNA, shRNA and miRNA) can trigger the silencing of specific genes causing alteration of genomic functions becoming a new therapeutic area for the treatment of infectious diseases, neurodegenerative disorders and cancer. In cancer treatment, RNAi effectors showed potential immunomodulatory actions by down-regulating immuno-suppressive proteins, such as PD-1 and CTLA-4, which restrict immune cell function and present challenges in cancer immunotherapy. Therefore, compared with extracellular targeting by antibodies, RNAi-mediated cell-intrinsic disruption of inhibitory pathways in immune cells could promote an increased anti-tumour immune response. Along with non-viral vectors, DNA-based RNAi strategies might be a more promising method for immunomodulation to silence multiple inhibitory pathways in T cells than immune checkpoint blockade antibodies. Thus, in this review, we discuss diverse RNAi implementation strategies, with recent viral and non-viral mediated RNAi synergism to immunotherapy that augments the anti-tumour immunity. Finally, we provide the current progress of RNAi in clinical pipeline.


Asunto(s)
MicroARNs , Neoplasias , Humanos , Inmunoterapia , Neoplasias/genética , Neoplasias/terapia , Interferencia de ARN , ARN Interferente Pequeño
9.
Bioact Mater ; 6(3): 613-626, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33005826

RESUMEN

The fate of mesenchymal stem cells (MSCs) is regulated by biological, physical and chemical signals. Developments in biotechnology and materials science promoted the occurrence of bioactive materials which can provide physical and chemical signals for MSCs to regulate their fate. In order to design and synthesize materials that can precisely regulate the fate of MSCs, the relationship between the properties of materials and the fate of mesenchymal stem cells need to be clarified, in which the detection of the fate of mesenchymal stem cells plays an important role. In the past 30 years, a series of detection technologies have been developed to detect the fate of MSCs regulated by bioactive materials, among which high-throughput technology has shown great advantages due to its ability to detect large amounts of data at one time. In this review, the latest research progresses of detecting the fate of MSCs regulated by bone bioactive materials (BBMs) are systematically reviewed from traditional technology to high-throughput technology which is emphasized especially. Moreover, current problems and the future development direction of detection technologies of the MSCs fate regulated by BBMs are prospected. The aim of this review is to provide a detection technical framework for researchers to establish the relationship between the properties of BMMs and the fate of MSCs, so as to help researchers to design and synthesize BBMs better which can precisely regulate the fate of MSCs.

10.
J Speech Lang Hear Res ; 64(1): 272-278, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33285083

RESUMEN

Purpose The plural is one of the first grammatical morphemes acquired by English-speaking children with normal hearing (NH). Yet, those with hearing loss show delays in both plural comprehension and production. However, little is known about the effects of unilateral hearing loss (UHL) on children's acquisition of the plural, where children's ability to perceive fricatives (e.g., the /s/ in cats ) can be compromised. This study therefore tested whether children with UHL were able to identify the grammatical number of newly heard words, both singular and plural. Method Eleven 3- to 5-year-olds with UHL participated in a novel word two-alternative forced choice task presented on an iPad. Their results were compared to those of 129 NH 3- to 5-year-olds. During the task, children had to choose whether an auditorily presented novel word was singular (e.g., tep, koss) or plural (e.g., teps, kosses) by touching the appropriate novel picture. Results Like their NH peers, children with UHL demonstrated comprehension of novel singulars. However, they were significantly less accurate at identifying novel plurals, with performance at chance. However, there were signs that their ability to identify novel plurals may improve with age. Conclusion While comparable to their NH peers at identifying novel singulars, these results suggest that young children with UHL do not yet have a robust representation of plural morphology, particularly on words they have not encountered before.


Asunto(s)
Sordera , Pérdida Auditiva Unilateral , Pérdida Auditiva , Preescolar , Comprensión , Audición , Humanos
11.
Ecotoxicol Environ Saf ; 195: 110469, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32179235

RESUMEN

To explore the mechanism of how lead (Pb) and cadmium (Cd) stress affects photosynthesis of mulberry (Morus alba L.), we looked at the effects of different concentrations of Pb and Cd stress (at 100 and 200 µmol L-1), which are two heavy metal elements, on leaf chlorophyll (Chl), photosynthesis gas exchange, Chl fluorescence, and reactive oxygen species (ROS) metabolism in mulberry leaves. The results showed that higher concentrations of Pb and Cd reduced leaf Chl content, especially in Chl a where content was more sensitive than in Chl b. Under Pb and Cd stress, the photosynthetic carbon assimilation capacity of mulberry leaves was reduced, which was a consequence of combined limitations of stomatal and non-stomatal factors. The main non-stomatal factors were decreased photosystem II (PSII) and photosystem I (PSI) activity and carboxylation efficiency (CE). Damage to the donor side of the PSII reaction center was greater than the acceptor side. After being treated with 100 µmol L-1 of Pb and Cd, mulberry leaves continued to be able to dissipate excess excitation energy by starting non-photochemical quenching (NPQ), but when Pb and Cd concentrations were increased to 200 µmol L-1, the protection mechanism that depends on NPQ was impaired. Excessive excitation energy from chloroplasts promoted a great increase of ROS, such as superoxide anion (O2•-) and H2O2. Moreover, under high Pb and Cd stress, superoxide dismutase (SOD) and ascorbate peroxidase (APX) were also inhibited to some extent, and excessive ROS also resulted in a significantly higher degree of oxidative damage. Compared with Cd, the effect of Pb stress at the same concentration level displayed a significantly lower impact on Chl content, photosynthetic carbon assimilation, and stomatal conductance. Meanwhile, Pb stress mainly damaged activity of the oxygen-evolving complex (OEC) located on PSII donor side, but it reduced the electronic pressure on the PSII acceptor side and PSI. Furthermore, under Pb stress, the NPQ, SOD, and APX activity were all significantly higher than those under Cd stress. Thus under Pb stress, the degree of photoinhibition and oxidative damage of PSII and PSI in mulberry leaves were significantly lower than under Cd stress.


Asunto(s)
Cadmio/toxicidad , Plomo/toxicidad , Morus/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ascorbato Peroxidasas/metabolismo , Clorofila/metabolismo , Cloroplastos/efectos de los fármacos , Cloroplastos/metabolismo , Peróxido de Hidrógeno/metabolismo , Morus/enzimología , Morus/metabolismo , Fotosíntesis/efectos de los fármacos , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Plantones/efectos de los fármacos , Plantones/metabolismo , Superóxido Dismutasa/metabolismo
12.
Ecotoxicol Environ Saf ; 193: 110259, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32097787

RESUMEN

In this paper, the effects of 100 mM NaCl and NaHCO3 stress on reactive oxygen species (ROS) and physiological and proteomic aspects of ROS metabolism in mulberry seedling leaves were studied. The results showed that NaCl stress had little effect on photosynthesis and respiration of mulberry seedling leaves. Superoxide dismutase (SOD) activity and the expression of related proteins in leaves increased by varying degrees, and accumulation of superoxide anion (O2·-) not observed. Under NaHCO3 stress, photosynthesis and respiration were significantly inhibited, while the rate of O2·- production rate and H2O2 content increased. The activity of catalase (CAT) and the expression of CAT (W9RJ43) increased under NaCl stress. In response to NaHCO3 stress, the activity and expression of CAT were significantly decreased, but the ability of H2O2 scavenging of peroxidase (POD) was enhanced. The ascorbic acid-glutathione (AsA-GSH) cycle in mulberry seedling leaves was enhancement in both NaCl and NaHCO3 stress. The expression of 2-Cys peroxiredoxin BAS1 (2-Cys Prx BAS1), together with thioredoxin F (TrxF), thioredoxin O1 (TrxO1), thioredoxin-like protein CITRX (Trx CITRX), and thioredoxin-like protein CDSP32 (Trx CDSP32) were significantly increased under NaCl stress. Under NaHCO3 stress, the expression of the electron donor of ferredoxin-thioredoxin reductase (FTR), together with Trx-related proteins, such as thioredoxin M (TrxM), thioredoxin M4 (TrxM4), thioredoxin X (TrxX), TrxF, and Trx CSDP32 were significantly decreased, suggesting that the thioredoxin-peroxiredoxin (Trx-Prx) pathway's function of scavenging H2O2 of in mulberry seedling leaves was inhibited. Taken together, under NaCl stress, excessive production of O2·- mulberry seedlings leaves was inhibited, and H2O2 was effectively scavenged by CAT, AsA-GSH cycle and Trx-Prx pathway. Under NaHCO3 stress, despite the enhanced functions of POD and AsA-GSH cycle, the scavenging of O2·- by SOD was not effective, and that of H2O2 by CAT and Trx-Prx pathway were inhibited; and in turn, the oxidative damage to mulberry seedling leaves could not be reduced.


Asunto(s)
Antioxidantes/metabolismo , Morus/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Bicarbonato de Sodio/toxicidad , Cloruro de Sodio/toxicidad , Peróxido de Hidrógeno/metabolismo , Morus/crecimiento & desarrollo , Morus/metabolismo , Peroxirredoxinas/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteómica , Plantones/efectos de los fármacos , Plantones/metabolismo , Tiorredoxinas/metabolismo
14.
Ecotoxicol Environ Saf ; 190: 110164, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31927191

RESUMEN

Chlorophyll (Chl) and effective photoprotective mechanism are important prerequisites to ensure the photosynthetic function of plants under stress. In this study, the effects of 100 mmol L-1 NaCl and NaHCO3 stress on chlorophyll synthesis and photosynthetic function of mulberry seedlings were studied by physiological combined with proteomics technology. The results show that: NaCl stress had little effect on the expression of Chl synthesis related proteins, and there were no significant changes in Chl content and Chl a:b ratio. However, 13 of the 15 key proteins in the process of Chl synthesis were significantly decreased under NaHCO3 stress, and the contents of Chl a and Chl b were significantly decreased (especially Chl a). Although stomatal conductance (Gs) decreased significantly under NaCl stress, net photosynthetic rate (Pn), PSII maximum photochemical efficiency (Fv/Fm) and electron transfer rate (ETR) did not change significantly, but under NaHCO3 stress, not only Gs decreased significantly, PSII activity and photosynthetic carbon were the same. In the photoprotective mechanism under NaCl stress, NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow (CEF) enhanced, the expression of related proteins subunit, ndhH, ndhI, ndhK, and ndhM, the key enzyme of the xanthophyll cycle, violaxanthin de-epoxidase (VDE) were up-regulated, the ratio of (A + Z)/(V + A + Z) and non-photochemical quenching (NPQ) was increased. The expressions of proteins FTR and Fd-NiR were also significant up-regulated under NaCl stress, Fd-dependent ROS metabolism and nitrogen metabolism can effectively reduce the electronic pressure on Fd. Under NaHCO3 stress, the expressions of NDH-dependent CEF related proteins subunit (ndhH, ndhI, ndhK, ndhM and ndhN), VDE, ZE, FTR, Fd-NiR and Fd-GOGAT, were significant down-regulated, and ZE, CP26, ndhK, ndhM, Fd-NiR, Fd-GOGAT and FTR genes expression also significantly decreased, the photoprotective mechanism, like the xanthophyll cycle,CEF and Fd-dependent ROS metabolism and nitrogen metabolism might be damaged, resulting in the inhibition of PSII electron transfer and carbon assimilation in mulberry leaves under NaHCO3 stress.


Asunto(s)
Clorofila/metabolismo , Morus/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Estrés Salino , Plantones/efectos de los fármacos , Bicarbonato de Sodio/toxicidad , Cloruro de Sodio/toxicidad , Transporte de Electrón , Morus/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteómica , Plantones/metabolismo
15.
Ecotoxicol Environ Saf ; 184: 109624, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31487570

RESUMEN

In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO3 stress were studied by using chlorophyll fluorescence and gas exchange technique combined with TMT proteomics. The results showed that NaCl stress had no significant effect on photosystem II (PSII) activity in M. alba seedling leaves. In addition, the expressions of proteins of the PSII oxygen-evolving complex (OEE3-1 and PPD4) and the LHCII antenna (CP24 10A, CP26, and CP29) were increased, and the photosystem I (PSI) activity in the leaves of M. alba seedlings was increased, as well as expressions of proteins, such as PsaF, PsaG, PsaH, PsaL, PsaN, and Ycf4. Under NaHCO3 stress, the activity of PSII and PSI and the expression of their protein complexes and the electron transfer-related proteins significantly decreased. NaCl stress had little effect on RuBP regeneration during dark reaction in the leaves and the expressions of glucose synthesis related proteins and net photosynthetic rate (Pn) did not decrease significantly. The leaves could adapt to NaCl stress by reducing stomatal conductance (Gs) and increasing water use efficiency (WUE). Under NaHCO3 stress, the expression of dark reaction-related proteins was mostly down-regulated, while Gs was reduced, which indicated that non-stomatal factors can be responsible for inhibition of carbon assimilation.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Morus/efectos de los fármacos , Estrés Salino , Bicarbonato de Sodio/toxicidad , Cloruro de Sodio/toxicidad , Adaptación Fisiológica/fisiología , Morus/metabolismo , Morus/fisiología , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteómica , Plantones/efectos de los fármacos , Plantones/metabolismo , Plantones/fisiología
16.
Cell Death Dis ; 10(3): 172, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30787286

RESUMEN

MicroRNAs (miRs) play an essential role in the regulation of bone formation and homeostasis. miR-185 has been reported to negatively regulate osteogenesis in vitro. However, whether it has an impact on in vivo bone homeostasis remains unknown. Here, we demonstrated that primary osteoblasts and mesenchymal stem cells derived from miR-185-knockout (KO) mice exhibited enhanced osteogenesis. Further, we constructed an ovariectomized mouse model to investigate the role of miR-185 during osteoporosis. Micro-computed tomography revealed an increased bone volume in KO compared to wild-type mice 6 weeks after surgery, indicating redundant bone formation after miR-185 depletion. Dual-luciferase reporter assays identified biglycan (Bgn), which promotes bone formation through the BMP/Smad pathway, as the direct target of miR-185. Taken together, these findings indicate that blocking miR-185 expression increases bone formation during osteoporosis, which may partly occur through the regulation of Bgn expression and BMP/Smad signaling.


Asunto(s)
Biglicano/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , MicroARNs/metabolismo , Osteoblastos/metabolismo , Osteoporosis/metabolismo , Proteínas Smad/metabolismo , Células 3T3 , Animales , Biglicano/antagonistas & inhibidores , Biglicano/genética , Huesos , Diferenciación Celular , Modelos Animales de Enfermedad , Estrógenos/metabolismo , Femenino , Regulación de la Expresión Génica , Células HEK293 , Humanos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Noqueados , MicroARNs/genética , Osteogénesis/genética , Osteoporosis/genética , Osteoporosis/patología , Ovariectomía , Transducción de Señal/genética , Microtomografía por Rayos X
17.
Exp Cell Res ; 376(1): 1-10, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30716301

RESUMEN

Glucoside xylosyltransferase2 (GXYLT2), a member of the human α-1,3-D-xylosyltransferases, functions to modify the first xylose to the O-Glucose residue on epidermal growth factor (EGF) repeats of Notch receptors. It is well-established that the Notch signaling pathway plays a critical role in proper development and homeostasis. However, the regulatory role of EGF xylosylation in Notch signaling and different cell activities in human cells remains unknown. In this study, we showed that knockdown of GXYLT2 suppressed human cell proliferation and induced G1/S phase cell cycle arrest. GXYLT2 downregulation also inhibited cell migration and invasion, whereas the overexpression of GXYLT2 had the opposite effects. Additionally, GXYLT2 activated Notch signaling and promoted the phosphorylation of MAPKs but not PI3K and Akt. Taken together, our findings indicated that GXYLT2 plays an important role in cell activities via regulation of the Notch signaling.


Asunto(s)
Neoplasias de la Mama/genética , Movimiento Celular/genética , Proliferación Celular/genética , Glicosiltransferasas/genética , Pentosiltransferasa/fisiología , Neoplasias de la Mama/patología , Factor de Crecimiento Epidérmico/genética , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Glucosa/genética , Humanos , Pentosiltransferasa/genética , Receptores Notch/genética , Xilosa/genética
18.
BMC Bioinformatics ; 20(Suppl 22): 719, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31888447

RESUMEN

BACKGROUND: Subcellular localization prediction of protein is an important component of bioinformatics, which has great importance for drug design and other applications. A multitude of computational tools for proteins subcellular location have been developed in the recent decades, however, existing methods differ in the protein sequence representation techniques and classification algorithms adopted. RESULTS: In this paper, we firstly introduce two kinds of protein sequences encoding schemes: dipeptide information with space and Gapped k-mer information. Then, the Gapped k-mer calculation method which is based on quad-tree is also introduced. CONCLUSIONS: >From the prediction results, this method not only reduces the dimension, but also improves the prediction precision of protein subcellular localization.


Asunto(s)
Algoritmos , Biología Computacional/métodos , Almacenamiento y Recuperación de la Información/métodos , Proteínas/química , Fracciones Subcelulares/metabolismo , Secuencia de Aminoácidos , Bases de Datos de Proteínas , Dipéptidos/química , Máquina de Vectores de Soporte
19.
RSC Adv ; 9(29): 16439-16446, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35516374

RESUMEN

A glucose biosensor based on Au nanoparticles (AuNPs), glucose oxidase (GOD) and polynorepinephrine (PNE) was fabricated by a simple and green approach. PNE-functionalized AuNPs (AuNPs@PNE) were synthetized by the polymerization of norepinephrine (NE) onto the surfaces of AuNPs and casted on an Au electrode. After dropping a solution containing NE and GOD on the AuNPs@PNE-modified Au electrode and oxidizing the monomer NE by cyclic voltammetry, a PNE, GOD and AuNP-modified Au electrode (PNE/GOD/AuNPs@PNE/Au) was obtained. The biosensor presented high sensitivity of 35.4 µA mM-1 cm-2 to glucose in the range from 0.003 mM to 3.43 mM with a response time of less than 3 s, a detection limit of 1.34 µM at a signal/noise ratio of 3, a low Michaelis-Menten constant (6.8 mM) and outstanding selectivity as well as stability. Moreover, the sensitivity and linear detection range of the as-prepared biosensor were further enhanced by the addition of the redox mediator p-benzoquinone.

20.
Biochem Biophys Res Commun ; 505(1): 249-254, 2018 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-30243719

RESUMEN

Ribosome biogenesis is a fundamental cellular process and occurs mainly in the nucleolus in eukaryotes. The process is exceptionally complex and highly regulated by numerous ribosomal and non-ribosomal factors. A recent discovery strengthened the link between ribosome biogenesis and malignant transformation. Here, we determined that Nop-7-associated 2 (NSA2) is a nucleolar protein required for ribosome biogenesis. NSA2 knockdown reduced the rate of rRNA synthesis, diminishing the 60S ribosomal subunit. Moreover, we demonstrated that depletion of NSA2 suppressed protein synthesis. To investigate the signaling pathway affected by NSA2, NSA2 was depleted, which triggered the inactivation of the mTOR signaling pathway. Taken together, our findings reveal a novel function of NSA2 and provide insight into the regulation of ribosome biogenesis by NSA2.


Asunto(s)
Proteínas Nucleares/metabolismo , Polirribosomas/metabolismo , Biosíntesis de Proteínas , Ribosomas/metabolismo , Secuencia de Aminoácidos , Células HCT116 , Células HEK293 , Humanos , Proteínas Nucleares/genética , Interferencia de ARN , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , Proteínas de Unión al ARN , Subunidades Ribosómicas Grandes de Eucariotas/genética , Subunidades Ribosómicas Grandes de Eucariotas/metabolismo , Ribosomas/genética , Homología de Secuencia de Aminoácido , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
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