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1.
Molecules ; 29(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38276572

RESUMEN

Selective supported catalysts have emerged as a promising approach to enhance carrier separation, particularly in the realm of photocatalytic hydrogen production. Herein, a pioneering exploration involves the loading of PdS and Pt catalyst onto g-C3N4 nanosheets to construct g-C3N4@PdS@Pt nanocomposites. The photocatalytic activity of nanocomposites was evaluated under visible light and full spectrum irradiation. The results show that g-C3N4@PdS@Pt nanocomposites exhibit excellent properties. Under visible light irradiation, these nanocomposites exhibit a remarkable production rate of 1289 µmol·g-1·h-1, marking a staggering 60-fold increase compared to g-C3N4@Pt (20.9 µmol·g-1·h-1). Furthermore, when subjected to full spectrum irradiation, the hydrogen production efficiency of g-C3N4@PdS@Pt-3 nanocomposites reaches an impressive 11,438 µmol·g-1·h-1, representing an eightfold enhancement compared to g-C3N4@Pt (1452 µmol·g-1·h-1) under identical conditions. Detailed investigations into the microstructure and optical properties of g-C3N4@PdS catalysts were conducted, shedding light on the mechanisms governing photocatalytic hydrogen production. This study offers valuable insights into the potential of these nanocomposites and their pivotal role in advancing photocatalysis.

2.
Molecules ; 28(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38067575

RESUMEN

Ultra-thin two-dimensional materials are attracting widespread interest due to their excellent properties, and they are becoming ideal candidates for a variety of energy and environmental photocatalytic applications. Herein, CdS nanorods are successfully grown in situ between a monolayer of g-C3N4 using a chemical water bath method. Continuous ultrasound is introduced during the preparation process, which effectively prevents the accumulation of a g-C3N4 layer. The g-C3N4@CdS nanocomposite exhibits significantly enhanced photocatalytic activity for hydrogen production under visible-light irradiation, which is attributed to a well-matched band structure and an intimate van der Waals heterojunction interface. The mechanism of photocatalytic hydrogen production is discussed in detail. Moreover, our work can serve as a basis for the construction of other highly catalytically active two-dimensional heterostructures.

3.
Molecules ; 28(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37110776

RESUMEN

The effects of variations in the heat treatment process of milk on its quality and flavor are inevitable. This study investigated the effect of direct steam injection and instantaneous ultra-high-temperature (DSI-IUHT, 143 °C, 1-2 s) sterilization on the physicochemical properties, whey protein denaturation (WPD) rate, and volatile compounds (VCs) of milk. The experiment compared raw milk as a control with high-temperature short-time (HTST, 75 °C 15 s and 85 °C 15 s) pasteurization and indirect ultra-high-temperature (IND-UHT, 143 °C, 3-4 s) sterilization. The results showed no significant differences (p > 0.05) in physical stability between milk samples with different heat treatments. The DSI-IUHT and IND-UHT milks presented smaller particle sizes (p < 0.05) and more concentrated distributions than the HTST milk. The apparent viscosity of the DSI-IUHT milk was significantly higher than the other samples (p < 0.05) and is consistent with the microrheological results. The WPD of DSI-IUHT milk was 27.52% lower than that of IND-UHT milk. Solid-phase microextraction (SPME) and solvent-assisted flavor evaporation (SAFE) were combined with the WPD rates to analyze the VCs, which were positively correlated with ketones, acids, and esters and negatively associated with alcohols, heterocycles, sulfur, and aldehydes. The DSI-IUHT samples exhibited a higher similarity to raw and HTST milk than the IND-UHT samples. In summary, DSI-IUHT was more successful in preserving the milk's quality due to its milder sterilization conditions compared to IND-UHT. This study provides excellent reference data for the application of DSI-IUHT treatment in milk processing.


Asunto(s)
Calor , Leche , Animales , Leche/química , Vapor , Temperatura , Esterilización , Proteína de Suero de Leche/análisis
4.
Small ; 18(40): e2204155, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36050884

RESUMEN

The coordination environment of Ru centers determines their catalytic performance, however, much less attention is focused on cluster-induced charge transfer in a Ru single-atom system. Herein, by density functional theory (DFT) calculations, a competitive coordination-pairing between Ru clusters (RuRu bond) and single-atoms (RuO bond) is revealed leading to the charge redistribution between Ru and O atoms in ZnFe2 O4 units which share more free electrons to participate in the hydrogen desorption process, optimizing the proton adsorption and hydrogen desorption. Thus, a clicking confinement strategy for building a competitive coordination-pairing between Ru clusters and single-atoms anchored on ZnFe2 Ox nanosheets over carbon via RuO ligand (Ru1, n -ZnFe2 Ox -C) is proposed. Benefiting from the optimized coordination effect and the electronic synergy between Ru clusters and single-atoms, such a catalyst demonstrates the excellent activity and excellent stability in alkaline and seawater media, which has exceptional hydrogen evolution reaction activity with overpotentials as low as 10.1 and 15.9 mV to reach the current density of 10 mA cm-2 in alkaline and seawater media, respectively, higher than that of commercial Pt/C catalysts as a benchmark. Furthermore, it owns remarkably outstanding mass activity, approximately 2 and 8 times higher than that of Pt catalysts in alkaline and seawater media, respectively.

5.
Analyst ; 145(3): 858-864, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-31845653

RESUMEN

A novel electrochemical biosensor was reported for the first time to achieve highly sensitive DNA detection based on photoinduced atom transfer radical polymerization (photoATRP). In this work, PNA was applied as the capture probe to specifically recognize the target DNA (TDNA), and we utilized lung cancer DNA as TDNA. The ATRP initiator was introduced to the electrode surface via phosphate-Zr4+-carboxylate chemistry. PhotoATRP was activated under blue light irradiation based on a photoinitiator I2959, which produced free radicals via homolytic cleavage. Subsequently, Cu2+ was reduced to Cu+ with the assistance of the free radicals, and numerous electroactive probes were grafted onto the electrode surface. Under optimal conditions, the limit of detection (LOD) of this method was 3.16 fM (S/N = 3, R2 = 0.992), and the linear range was from 10 fM to 1.0 nM. More importantly, the preparation process of this biosensor was simple and less laborious with a low background signal, suggesting good potential in practical applications.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/análisis , ADN de Neoplasias/análisis , Técnicas Electroquímicas , Electrodos , Humanos , Luz , Límite de Detección , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Polimerizacion
6.
J Cell Physiol ; 233(9): 6742-6749, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29226348

RESUMEN

This study aimed to detect the effect of sevoflurane anesthesia on liver injury through modulating IGF-1. The expression of IGF-1 and IGF-1R in liver tissues of sevoflurane-exposed rats was examined by qRT-PCR and Western blot. The expression levels of miR-214 in liver cells treated with different concentration of sevoflurane at different time points were detected by qRT-PCR. Enzyme-linked immunosorbent (ELISA) assay was used to analyze serum IGF-1 concentration in cell culture media. After pre-treatment with 100 nM miR-214 inhibitor followed by exposure to sevoflurane, the expression level of miR-214 and IGF-1 protein in liver cells was examined. Hematoxylin-Eosin (HE) staining and TUNEL assay was performed to analyze liver tissue necrosis and apoptosis. The expression levels of apoptosis-related proteins (caspase 3 and Bcl-xL) were examined using Western blot. The mRNA and protein expression level of IGF-1 and IGF-1R in rats was significantly down-regulated after 90 min exposure to sevoflurane. QRT-PCR results suggested that exposure to sevoflurane upregulated the expression level of miR-214 and decreased the concentration of IGF-1 in a dose and time dependent manner. Sevoflurane inhibited the expression of IGF-1 through up-regulating miR-214. IGF-1 inhibited the positive effect of sevoflurane on cell necrosis and apoptosis. Sevoflurane could induce liver injury by modulating IGF-1 expression via miR-214.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Hígado/efectos de los fármacos , MicroARNs/metabolismo , Sevoflurano/farmacología , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Hígado/metabolismo , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor IGF Tipo 1/metabolismo , Regulación hacia Arriba/efectos de los fármacos
7.
Mol Pain ; 13: 1744806917706582, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28580822

RESUMEN

Objective To investigate the effects of microRNA-223 on morphine analgesic tolerance by targeting NLRP3 in a rat model of neuropathic pain. Methods Our study selected 100 clean grade healthy Sprague-Dawley adult male rats weighing 200 to 250 g. After establishment of a rat model of chronic constriction injury, these rats were divided into 10 groups (10 rats in each group): the normal control, sham operation, chronic constriction injury, normal saline, morphine, miR-223, NLRP3, miR-223 + morphine, NLRP3 + morphine, and miR-223 + NLRP3 + morphine groups. The real-time quantitative polymerase chain reaction assay, Western blotting, and enzyme-linked immunosorbent assay were used for detecting the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, Interleukin (IL)-1ß, and IL-18 in sections of lumbar spinal cord. Immunohistochemistry was applied for detecting the positive rates of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1ß, and IL-18. Results The paw withdrawal threshold and percentage maximum possible effect (%MPE) were higher in chronic constriction injury group when compared with the normal control and sham operation groups. Behavioral tests showed that compared with the chronic constriction injury and normal saline groups, the morphine and miR-223 + morphine groups showed obvious analgesic effects. Expressions of miR-223 in the miR-223, miR-223 + morphine, and miR-223 + NLRP3 + morphine were significantly higher than those in the chronic constriction injury, normal saline, and morphine groups. Compared with chronic constriction injury, normal saline and morphine groups, the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1ß, and IL-18 were significantly decreased in the miR-223 and miR-223 + morphine groups, while mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1ß, and IL-18 were significantly increased in the NLRP3 and NLRP3 + morphine group. Conclusion Our study provides strong evidence that miR-223 could suppress the activities of NLRP3 inflammasomes ( NLRP3, apoptosis-associated speck-like protein, and Caspase-1) to relieve morphine analgesic tolerance in rats by down-regulating NLRP3.


Asunto(s)
MicroARNs/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Neuralgia/tratamiento farmacológico , Neuralgia/metabolismo , Analgésicos Opioides/uso terapéutico , Animales , Inmunohistoquímica , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , MicroARNs/genética , Morfina , ARN Mensajero/metabolismo , Ratas Sprague-Dawley
8.
Cell Physiol Biochem ; 41(1): 181-192, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28214854

RESUMEN

BACKGROUND: Neuropathic pain is a type of chronic pain that results from dysfunctions of the somatosensory nerve system. This study was aimed to investigate the effect of mTOR/VEGF signaling pathway on neuropathic pain and the regulation mechanisms of miR-183 on AMPA Receptors through mTOR/VEGF signaling pathway. METHODS: Chronic compress injury (CCI) model was constructed in the current study, we used paw withdrawal mechanic threshold (PWMT) and paw withdrawal thermal latency (PWTL) to observe mTOR and VEGF receptors. Dual luciferase analysis, western blot and qRT-PCR were also applied to complete this experiment. RESULTS: It was observed that the inhibition of mTOR and VEGF receptors could significantly relieve neuropathic pain in the CCI model. Moreover mTOR was confirmed as the direct target of miR-183. Furthermore, miR-183 could modulate VEGF through regulating mTOR expressions. We also found the expressions of AMPA receptors (i.e. GluR1 and GluR2), located in the downstream of mTOR/VEGF signaling pathway, were significantly upregulated when miR-183 was downregulated or when the mTOR/VEGF signaling pathway was activated. CONCLUSION: The inhibition of mTOR or VEGF receptors can significantly relieve neuropathic pain, and the upregulation of miR-183 can suppress AMPA receptors by inhibiting mTOR/VEGF pathway.


Asunto(s)
MicroARNs/metabolismo , Neuralgia/patología , Receptores AMPA/metabolismo , Regiones no Traducidas 3' , Animales , Secuencia de Bases , Modelos Animales de Enfermedad , Regulación hacia Abajo , Inmunohistoquímica , Masculino , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Neuralgia/metabolismo , Oligonucleótidos/química , Oligonucleótidos/metabolismo , Células PC12 , Ratas , Ratas Sprague-Dawley , Receptores AMPA/genética , Alineación de Secuencia , Transducción de Señal , Médula Espinal/metabolismo , Médula Espinal/patología , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
PLoS Biol ; 11(9): e1001655, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24058297

RESUMEN

Plant zygote divides asymmetrically into an apical cell that develops into the embryo proper and a basal cell that generates the suspensor, a vital organ functioning as a conduit of nutrients and growth factors to the embryo proper. After the suspensor has fulfilled its function, it is removed by programmed cell death (PCD) at the late stages of embryogenesis. The molecular trigger of this PCD is unknown. Here we use tobacco (Nicotiana tabacum) embryogenesis as a model system to demonstrate that the mechanism triggering suspensor PCD is based on the antagonistic action of two proteins: a protease inhibitor, cystatin NtCYS, and its target, cathepsin H-like protease NtCP14. NtCYS is expressed in the basal cell of the proembryo, where encoded cystatin binds to and inhibits NtCP14, thereby preventing precocious onset of PCD. The anti-cell death effect of NtCYS is transcriptionally regulated and is repressed at the 32-celled embryo stage, leading to increased NtCP14 activity and initiation of PCD. Silencing of NtCYS or overexpression of NtCP14 induces precocious cell death in the basal cell lineage causing embryonic arrest and seed abortion. Conversely, overexpression of NtCYS or silencing of NtCP14 leads to profound delay of suspensor PCD. Our results demonstrate that NtCYS-mediated inhibition of NtCP14 protease acts as a bipartite molecular module to control initiation of PCD in the basal cell lineage of plant embryos.


Asunto(s)
Catepsina H/metabolismo , Cistatinas/metabolismo , Nicotiana/embriología , Semillas/embriología , Secuencia de Aminoácidos , Muerte Celular , Linaje de la Célula/genética , Cistatinas/biosíntesis , Cistatinas/genética , Regulación de la Expresión Génica de las Plantas , Unión Proteica , Semillas/genética , Semillas/metabolismo , Alineación de Secuencia , Nicotiana/metabolismo
10.
Yao Xue Xue Bao ; 51(10): 1643-50, 2016 10.
Artículo en Zh | MEDLINE | ID: mdl-29932621

RESUMEN

Jasmonic acid carboxyl methyltransferase(JMT), a key enzyme for jasmonate(JA) biosynthesis, catalyzes the methylation of JA to form Me JA. To characterize the function of JMT, a plasmid pGEX-4T- SmJMT1 harboring JMT1(SmJMT1) gene from Salvia miltiorrhiza was successfully transformed into E. coli BL21(DE3) for protein expression. The recombination SmJMT1 was separated using SDS-PAGE and the size of expressed SmJMT1 protein was consistent with the prediction. The bacterial growth conditions were determined for optimal expression, which include growth temperature, incubation time, IPTG concentrations and culture density. The optimal growth conditions for SmJMT1 were that the bacterial cultures were grown to an A600 of 0.8, and induced with IPTG at a final concentration of 0.4 mmol·L-1, and then incubated for 8 h at 20 ℃. The expression of SmJMT1 in E. coli was confirmed by Western blotting, and mass spectrometry analysis of methyltransferase family. The successful expression and purification of JMT in this study provide the basis for more study of JA biosynthetic pathway and JA-regulated secondary metabolism of medicinal plants.


Asunto(s)
Metiltransferasas/biosíntesis , Proteínas de Plantas/biosíntesis , Salvia miltiorrhiza/enzimología , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Plásmidos
11.
Genes (Basel) ; 15(2)2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38397145

RESUMEN

Rehmannia glutinosa, a member of the Scrophulariaceae family, has been widely used in traditional Chinese medicine since ancient times. The main bioactive component of R. glutinosa is catalpol. However, the biogenesis of catalpol, especially its downstream pathway, remains unclear. To identify candidate genes involved in the biosynthesis of catalpol, transcriptomes were constructed from R. glutinosa using the young leaves of three cultivars, Beijing No. 3, Huaifeng, and Jin No. 9, as well as the tuberous roots and adventitious roots of the Jin No. 9 cultivar. As a result, 71,142 unigenes with functional annotations were generated. A comparative analysis of the R. glutinosa transcriptomes identified over 200 unigenes of 13 enzymes potentially involved in the downstream steps of catalpol formation, including 9 genes encoding UGTs, 13 for aldehyde dehydrogenases, 70 for oxidoreductases, 44 for CYP450s, 22 for dehydratases, 30 for decarboxylases, 19 for hydroxylases, and 10 for epoxidases. Moreover, two novel genes encoding geraniol synthase (RgGES), which is the first committed enzyme in catalpol production, were cloned from R. glutinosa. The purified recombinant proteins of RgGESs effectively converted GPP to geraniol. This study is the first to discover putative genes coding the tailoring enzymes mentioned above in catalpol biosynthesis, and functionally characterize the enzyme-coding gene in this pathway in R. glutinosa. The results enrich genetic resources for engineering the biosynthetic pathway of catalpol and iridoids.


Asunto(s)
Monoterpenos Acíclicos , Glucósidos Iridoides , Plantas Medicinales , Rehmannia , Plantas Medicinales/genética , Rehmannia/genética , Rehmannia/metabolismo , Perfilación de la Expresión Génica
12.
Artículo en Inglés | MEDLINE | ID: mdl-39136503

RESUMEN

BACKGROUND: Si-Ni-San (SNS) is the formula prescription of Traditional Chinese Medicine (TCM) with anti-depression properties, but its underlying mechanisms remain unclear. OBJECTIVE: This study provides novel approaches for the study of Traditional Chinese Medicine (TCM) and offers new opportunities for exploring the pharmacological properties of SNS. METHODS: The ingredients in SNS implicated in the treatment of depression were identified and studied using network pharmacology. SwissTargetPrediction and molecular docking were used to study the interaction of SNS ingredients and their targets. The protective effect of these ingredients and their cocktail in rat pheochromocytoma cells (PC12) exposed to corticosterone (Cor) were evaluated using the CCK-8 assay, Hoechst 33342 staining, 2',7'-dichlorodihydro fluorescein diacetate (H2DCFDA) staining, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and in-cell Western analysis. RESULTS: The network pharmacology study showed that the HIF-1 signaling pathway was the most crucial pathway implicated in the anti-depressive property of SNS. MAPK1 (ERK2), MAPK3 (ERK1), AKT1, VEGFA, STAT3, and EGF were identified as hub target proteins in the HIF-1 signaling pathway. Quercetin, naringenin, licochalcone A, and kaempferol from SNS, which targeted the six proteins mentioned above, were used to create a cocktail. This cocktail exerted protective properties, decreased the oxidative stress in PC12 exposed to Cor, and successfully regulated the expressions of AKT1, p-AKT1, ERK1, ERK2, p-ERK1/2, STAT3, p- STAT3, and VEGFA induced by Cor exposure. The SwissTargetPrediction and molecular docking study showed that the cocktail may regulate the HIF-1 signaling pathway by directly binding with AKT1 and MAPK1. CONCLUSION: The cocktail from SNS comprised of quercetin, naringenin, licochalcone A, and kaempferol exerts anti-depression potentiality by modulating the HIF-1 signaling pathway via direct interactions with AKT1 and MAPK1.

13.
J Exp Bot ; 64(1): 215-28, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23162119

RESUMEN

The roles of cell polarity and the first asymmetric cell division during early embryogenesis in apical-basal cell fate determination remain unclear. Previously, a novel Brassica napus microspore embryogenesis system was established, by which rape exine-dehisced microspores were induced by physical stress. Unlike traditional microspore culture, cell polarity and subsequent asymmetric division appeared in the exine-dehisced microspore, which finally developed into a typical embryo with a suspensor. Further studies indicated that polarity is critical for apical-basal cell fate determination and suspensor formation. However, the pattern of the first division was not only determined by cell polarity but was also regulated by the position of the ruptured exine. The first division could be equal or unequal, with its orientation essentially perpendicular to the polar axis. In both types of cell division, the two daughter cells could have different cell fates and give rise to an embryo with a suspensor, similar to zygotic apical-basal cell differentiation. The alignment of the two daughter cells is consistent with the orientation of the apical-basal axis of future embryonic development. Thus, the results revealed that exine dehiscing induces rape microspore polarization, and this polarity results in a different cell fate and fixes the apical-basal axis of embryogenesis, but is uncoupled from cell asymmetric division. The present study demonstrated the relationships among cell polarity, asymmetric cell division, and cell fate determination in early embryogenesis.


Asunto(s)
Brassica napus/citología , Linaje de la Célula , Polaridad Celular , Polen/anatomía & histología , Polen/citología , Semillas/citología , Brassica napus/embriología , Brassica napus/ultraestructura , División Celular , Modelos Biológicos , Polen/ultraestructura
14.
Nanomaterials (Basel) ; 13(8)2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37110956

RESUMEN

Photocatalyst performance is often limited by the poor separation and rapid recombination of photoinduced charge carriers. A nanoheterojunction structure can facilitate the separation of charge carrier, increase their lifetime, and induce photocatalytic activity. In this study, CeO2@ZnO nanocomposites were produced by pyrolyzing Ce@Zn metal-organic frameworks prepared from cerium and zinc nitrate precursors. The effects of the Zn:Ce ratio on the microstructure, morphology, and optical properties of the nanocomposites were studied. In addition, the photocatalytic activity of the nanocomposites under light irradiation was assessed using rhodamine B as a model pollutant, and a mechanism for photodegradation was proposed. With the increase in the Zn:Ce ratio, the particle size decreased, and surface area increased. Furthermore, transmission electron microscopy and X-ray photoelectron spectroscopy analyses revealed the formation of a heterojunction interface, which enhanced photocarrier separation. The prepared photocatalysts show a higher photocatalytic activity than CeO2@ZnO nanocomposites previously reported in the literature. The proposed synthetic method is simple and may produce highly active photocatalysts for environmental remediation.

15.
Plant J ; 65(1): 131-145, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21175896

RESUMEN

The maternal-to-zygotic transition (MZT) is characterized by the turnover of zygote development from maternal to zygotic control, and has been extensively studied in animals. A majority of studies have suggested that early embryogenesis is maternally controlled and that the zygotic genome remains transcriptionally inactive prior to the MZT. However, little is known about the MZT in higher plants, and its timing and impact remain uncharacterized. Here, we constructed cDNA libraries from tobacco (Nicotiana tabacum) egg cells, zygotes and two-celled embryos for gene expression profiling analysis, followed by RT-PCR confirmation. These analyses, together with experiments using zygote microculture coupled with transcription inhibition, revealed that a marked change in transcript profiles occurs approximately 50 h after fertilization, and that the MZT is initiated prior to zygotic division in tobacco. Although maternal transcripts deposited in egg cells support several early developmental processes, they appear to be insufficient for zygotic polar growth and subsequent cell divisions. Thus, we propose that de novo transcripts are probably required to trigger embryogenesis in later zygotes in tobacco.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Nicotiana/embriología , Cigoto/citología , ADN Complementario/genética , Perfilación de la Expresión Génica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Nicotiana/citología
16.
Nanomaterials (Basel) ; 12(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35407242

RESUMEN

The degradation of pollutants in wastewater using abundant resources and renewable energy sources, such as light, is attractive from an environmental perspective. ZnO is a well-known photocatalytic material. Therefore, in this study, a hierarchical ZnO microsphere precursor was prepared using a hydrothermal method. The precursor was subsequently annealed at different temperatures, which enabled the production of a ZnO catalyst having a controllable morphology. Specifically, as the annealing temperature increased, the precursor crystallized into hexagonal wurtzite and the crystallinity also increased. The catalysts were tested for their photocatalytic activity for the degradation of dye molecules (methylene blue and rhodamine B), and the catalyst sample annealed at 400 °C showed the best photocatalytic activity. The origin of this activity was studied using electron paramagnetic resonance spectroscopy and transient photocurrent measurements, and the structure of the optimal catalyst was invested using electron microscopy measurements, which revealed that it was formed of two-dimensional nanosheets having smooth surfaces, forming a 2D cellular network. Thus, we have presented a promising photocatalyst for the mineralization of organic contaminants in wastewater.

17.
Biomed Res Int ; 2022: 3370499, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35928920

RESUMEN

Baseball itself is a new sport. In the process of training, teachers often use traditional training methods, which leads to unsatisfactory training results. High-intensity intermittent and intensive interval training can better improve the efficiency of athletes' oxidation and energy supply and ultimately play a positive role in improving athletes' performance. This paper takes the influence of high-intensity and intensive interval training on the special endurance of baseball players as the research object. A series of functional training programs are developed through adaptive training, testing, coordination training, and recovery training. Through the use of experimental means to understand the influence of high-intensity interval training and intensive interval training on the physical fitness of baseball players, the paper is aimed at providing ways and means to improve the physical fitness level of baseball players in the future. Based on the experimental test data, functional training is different from traditional training methods to make up for the lack of training research. It is to improve the competitive ability of our baseball players and promote the development of our baseball. It plays an active role in improving the specific endurance, speed, and intermittent endurance of baseball players.


Asunto(s)
Rendimiento Atlético , Béisbol , Entrenamiento de Intervalos de Alta Intensidad , Atletas , Humanos , Aptitud Física
18.
Biomed Res Int ; 2022: 7378953, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35832853

RESUMEN

In the past, in the study of special sports quality of heavy antagonistic sports events, the study of strength quality training was emphasized. The transformation of athletes' strength quality to special strength was highlighted, and the special exercises which tended to be consistent with the characteristics of wrestling events were added. However, in competition and training, athletes' spine bears a heavy load. Long-term static contraction of lumbar muscles can lead to excessive local load and injury of lumbar muscles. In this paper, the test results of athletes' joints are analyzed, and the waist protection scheme for athletes' strength training is obtained. First of all, solve the problem of athletes' action mode and improve athletes' muscle endurance. All special sports quality evaluation can reach a good level. Then, enhance athletes' explosive power. Thus, all special sports quality evaluations can reach an excellent level. It is concluded that the waist and back are the key parts to support their participation in various sports, maintain body balance, and realize power transmission. Through the study, it is found that there are significant differences in the muscle strength indexes of the maximum strength of the waist and back of athletes of different levels, which fully proves the characteristics of the maximum strength of the waist and back. Through the test, we can understand the flexion and extension strength, range, speed, force, and flexion and extension ratio of athletes' joints and take timely optimization measures according to the test results to avoid sports injuries in training. It has a key guiding significance for the measurement, analysis, and evaluation of athletes' joint muscle strength, as well as rehabilitation training after injury and prevention of reinjury.


Asunto(s)
Entrenamiento de Fuerza , Deportes , Atletas , Humanos , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Deportes/fisiología
19.
Biomed Res Int ; 2022: 4625719, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35774272

RESUMEN

In the process of competition and training, tennis players often carry out explosive force and extreme centripetal and eccentric contraction, while the ligament and joint capsule on the shoulder joint are relatively weak, which also makes the joint often appear injury caused by overuse. It has been the direction of scientific research to help athletes recover their functions and return to the arena through effective rehabilitation training and prerehabilitation training. In this paper, the reliability and short-term effect of wearing dynamic and static shoulder joint brace after arthroscopic repair of rotator cuff injury were studied through a controlled trial of tennis exercise for the treatment of shoulder injury. The purpose of this study was to apply the dynamic and static shoulder joint brace to patients with rotator cuff injury and shorten the recovery time of shoulder joint function the operation. This paper also studies the therapeutic effect verification of patients with rotator cuff injury during rehabilitation period by wearing shoulder joint brace with dynamic and static combination. Through the comparison between the experimental group and the control group, it is verified that the effect of rehabilitation intervention is better than that of the control group, which shows that the use of dynamic and static shoulder joint brace can improve the range of motion of shoulder joint and patient satisfaction, and the effect increases with time. This study improves the shoulder strength of tennis players through functional training, demonstrates the value and significance of functional training for the development of tennis through experiments, and provides a reference for athletes to improve their physical fitness training. At the same time, the research content of this paper can also provide references and promotion for sports events.


Asunto(s)
Lesiones del Manguito de los Rotadores , Lesiones del Hombro , Articulación del Hombro , Tenis , Humanos , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Manguito de los Rotadores
20.
Nanomaterials (Basel) ; 12(20)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36296854

RESUMEN

The design and construct pn heterojunction to reduce the recombination rate of photogenerated electron-hole pairs can effectively improve photocatalytic activity. In this study, ZnO/NiO heterojunctions were fabricated by annealing a Zn/Ni metal organic framework precursor synthesized via coprecipitation. The effects of the precursor annealing temperature on the microstructure, morphology, and optical properties of the ZnO/NiO nanocomposites were investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis absorption spectroscopy. The results showed that the nanocomposite was composed of hexagonal wurtzite ZnO and cubic NiO, with the former being the dominant phase. Large ZnO nanoparticles were attached to small NiO nanoparticles, and a pn heterojunction interface was formed. The photodegradation performance of the nanomaterials was evaluated by monitoring the degradation of RhB under irradiation by ultraviolet light. The ZnO/NiO nanocomposites exhibited excellent photocatalytic activity when the annealing temperature was 550 °C. The photodegradation mechanism was also analyzed in detail, revealing that the heterojunction between the n-type ZnO and the p-type NiO played an important role in impeding the recombination of photogenerated electron-hole pairs and improving the photocatalytic efficiency.

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