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1.
Biochem Biophys Res Commun ; 647: 62-71, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36731335

RESUMO

BACKGROUND: Dysfunction of pancreatic ß-cells induced by glucocorticoids contributes to diabetes mellitus development. Long noncoding RNAs (lncRNAs) have been recognized to contain short open reading frames (ORFs) that can be translated into functional small peptides. Here, we investigated whether the short peptide encoded by the lncRNA MIR7-3 host gene (MIR7-3HG) can affect dexamethasone (DEX)-induced ß-cell dysfunction. METHODS: Bioinformatics analysis was used for selection of MIR7-3HG and prediction of its protein encoding potential. The small peptide was identified by a western blot method. The cell-permeable TAT was fused into MIR7-3HG ORF to produce the cell-permeable fusion peptide (TAT-MIR7-3HG-ORF). The effects of TAT-MIR7-3HG-ORF on DEX-induced ß-cell dysfunction were evaluated by examining cell viability, apoptosis, insulin secretion, and reactive oxygen species (ROS) generation. RESULTS: DEX induced ß-TC6 cell dysfunction by impairing cell viability, insulin secretion and promoting cell apoptosis and ROS generation. The MIR7-3HG ORF could encode a 125-amino-acid-long short peptide. TAT-MIR7-3HG-ORF effectively transduced into ß-TC6 cells and attenuated DEX-induced dysfunction in ß-TC6 cells. Moreover, transduced TAT-MIR7-3HG-ORF reversed DEX-mediated inhibition of the activation of the PI3K/AKT signaling pathway. The inhibitor of the PI3K/AKT pathway partially abolished the alleviative effect of transduced TAT-MIR7-3HG-ORF on DEX-induced ß-TC6 cell dysfunction. CONCLUSION: The lncRNA MIR7-3HG encodes a short peptide, which can protect pancreatic ß-cells from DEX-induced dysfunction by activating the PI3K/AKT pathway. Our study broadens the diversity and breadth of lncRNAs in human disorders.


Assuntos
Células Secretoras de Insulina , MicroRNAs , RNA Longo não Codificante , Humanos , Apoptose/genética , Dexametasona/efeitos adversos , MicroRNAs/genética , MicroRNAs/farmacologia , Peptídeos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Células Secretoras de Insulina/efeitos dos fármacos
2.
Physiol Plant ; 174(2): e13636, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35122261

RESUMO

Nitrogen (N) is one of the most important nutrients for crop growth and yield formation, as it is an important constituent in a large amount of proteins, cell walls, and membranes related to photosynthesis. Recently, increasing studies have suggested the important roles of photosynthetic induction and stomatal movement under fluctuating light in regulating plant carbon assimilation and water use efficiency. How leaf N content affects photosynthetic induction remains uncertain. Here, we observed a significantly faster photosynthetic induction with the increasing supply of N under fluctuating light conditions. Photosynthetic induction was mainly limited by biochemical processes but not stomatal opening after a stepwise increase in irradiance across different N supplies. Higher N supply enhanced photosynthetic efficiency under constant and fluctuating light conditions but reduced leaf intrinsic water use efficiency (WUEi ). This study is mainly focused on clarifying the crucial limitation of photosynthetic induction under different N treatments, which may facilitate the improvement of photosynthetic efficiency under complicated environments in the future.


Assuntos
Oryza , Luz , Nitrogênio/metabolismo , Oryza/metabolismo , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Água/metabolismo
3.
IUBMB Life ; 73(11): 1325-1333, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34409730

RESUMO

Emerging evidence has demonstrated that N6 -methyladenosine (m6 A) and long noncoding RNAs (lncRNAs) are both crucial regulators in gastric cancer (GC) tumorigenesis. However, the interaction of m6 A and lncRNAs in GC progression are still unclear. Here, our team discovered that lncRNA LINC00958 expression up-regulated in GC tissue and cells. Clinically, high-expression of LINC00958 was clinically correlated to lower survival of GC patients. Functionally, in vitro assays demonstrated that LINC00958 promoted the GC cells' aerobic glycolysis. Mechanistically, methylated RNA immunoprecipitation sequencing (MeRIP-Seq) found that there were m6 A-modificated sites in LINC00958, and moreover m6 A methyltransferase KIAA1429 catalyzed the m6 A modification on LINC00958 loci. Moreover, LINC00958 interacted with GLUT1 mRNA via the m6 A-dependent manner to enhance GLUT1 mRNA transcript stability, thereby positively regulating the aerobic glycolysis of GC. In conclusion, our findings reveal the function and mechanism of KIAA1429-induced LINC00958 in GC, delineating novel understanding of m6 A-lncRNA in cancer biology.


Assuntos
Transportador de Glucose Tipo 1/genética , Glicólise/genética , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Neoplasias Gástricas/genética , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/metabolismo , Humanos , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Estabilidade de RNA , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Cell Biochem ; 121(2): 1353-1361, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31478258

RESUMO

The aim of this study was to investigate the functional role and the underlying molecular mechanism of long noncoding RNA (lncRNA) prostate cancer-associated transcript 1 (PCAT-1) in cisplatin resistance of gastric cancer (GC). Our results indicated that PCAT-1 was overexpressed in CDDP-resistant GC tumor tissues and cell lines. High expression of PCAT-1 was closely correlated with short overall survival in patients with GC. Downregulation of PCAT-1 resensitized CDDP-resistant GC cells to cisplatin. In addition, PCAT-1 epigenetically silenced PTEN through binding to the histone methyltransferase enhancer of zeste homolog 2 (EZH2), thus increasing H3K27me3. More importantly, PTEN silencing counteracted PCAT-1 knockdown-mediated enhancement in cisplatin sensitivity of CDDP-resistant GC cells. In summary, PCAT-1 led to cisplatin resistance in GC cells through epigenetically suppressing PTEN expression, providing a novel therapeutic strategy for GC patients with chemoresistance.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , PTEN Fosfo-Hidrolase/antagonistas & inibidores , RNA Longo não Codificante/genética , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Regulação Neoplásica da Expressão Gênica , Humanos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(4): 314-317, 2018 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29658458

RESUMO

OBJECTIVE: To explore the abilities of verbal and visual-spatial memory in Chinese children with developmental dyslexia. METHODS: Thirty-two children with developmental dyslexia (aged 8-12 years) and thirty-nine age- and gender-matched normal children were involved in the study. Their verbal short-term and verbal working memories were measured using the digit ordering and the digit span tests, respectively. Their visual-spatial short-term and visual-spatial working memories were examined using the forward and backward block-tapping tests, respectively. RESULTS: The DD children scored lower in the digit ordering and the digit span tests than the control children (P<0.05). The scores for the forward and backward block-tapping tests did not vary between the two groups (P>0.05). CONCLUSIONS: The children with DD have the deficits in both verbal short-term memory and verbal working memory.


Assuntos
Dislexia/psicologia , Memória de Curto Prazo , Memória Espacial , Criança , Feminino , Humanos , Masculino
6.
Int Orthop ; 41(5): 901-909, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27650276

RESUMO

PURPOSE: Removal of an infected prosthesis was considered the gold standard for eradication of infection. However, removal of well-fixed components can result in structural bone damage and compromised reconstruction. In these situations we questioned whether the infection after the total hip arthroplasty could be treated effectively and retain the well-fixed implant in a single-stage exchange. METHODS: A retrospective analysis which included 31 patients with chronic infected THA who underwent major partial single-stage revision, including routinely exchanged femoral head and liner components, aggressive soft tissue debridement, removal of the femoral stem or acetabular cup and retention of the well-fixed component, thorough exposed component brushing, and adequate surgical soaking. Powdered Vancomycin was poured into the surgical area and the infection control rate and clinical outcomes were evaluated. The failure to treat the infection was defined as a recurrence of infection in the same hip. The average follow-up was five years (2-15 years). RESULT: There were four (12.9 %) failures during the study period at an average of 15 months (9-21 months) after partial single-stage revision. Of the 31 patients, 27 (87.1 %) patients had a satisfactory outcome and required no additional surgical or medical treatment for recurrence of infection. Acetabular cups were revised in 22 patients and femoral stems in nine patients. The mean post-operative Harris hip score at the most recent assessment was 74.6 (68-82). CONCLUSIONS: Treatment of chronic infected THA with retention of the well-fixed implant in a single-stage exchange can be fairly effective in the treatment of infection and achieving acceptable functional outcomes, which indicated that this may be an attractive alternative in highly selected patients. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Artroplastia de Quadril , Infecções Relacionadas à Prótese/cirurgia , Administração Tópica , Adulto , Idoso , Antibacterianos/administração & dosagem , Artroplastia de Quadril/efeitos adversos , Doença Crônica , Remoção de Dispositivo , Feminino , Seguimentos , Prótese de Quadril/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Osseointegração , Infecções Relacionadas à Prótese/etiologia , Reoperação , Estudos Retrospectivos , Vancomicina/administração & dosagem , Adulto Jovem
7.
J Arthroplasty ; 31(3): 668-75, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26643734

RESUMO

BACKGROUND: Developmental dysplasia of the hip (DDH) is widespread in developing countries, and treating Crowe IV-Hartofilakidis Type III DDH in adults requires the use of a highly demanding technique. METHODS: We sought to determine the outcome of cementless total hip arthroplasty using Zweymüller components to treat Crowe IV-Hartofilakidis Type III DDH. Fifty-eight patients (71 hips) with a mean age of 35.8 years at time of index operation were included in our study. The average duration of follow-up was 70.5 months. The acetabular component was placed in the true acetabulum in all cases, and subtrochanteric shortening osteotomy was performed in 61 hips. RESULTS: With any component revision for any reason as the end point, Kaplan-Meier survivorship analysis at 98 months revealed a cumulative survival rate for implanted components of 91.40%. The mean Harris Hip Score improved from 35.6 preoperatively to 82.9 postoperatively. There were 20 cases of intraoperative fracture, 1 case of complete nerve palsy, and 7 cases of transient nerve palsy. Revision surgery was performed in 7 patients because of cup loosening in 1, severe polyethylene wear in 4, cup breakage in 1, and dislocation in 1. CONCLUSIONS: Midterm results for cementless total hip arthroplasty in patients with Crowe IV-Hartofilakidis Type III DDH was satisfactory; however, intraoperative fracture and polyethylene wear were major complications.


Assuntos
Artroplastia de Quadril/métodos , Luxação Congênita de Quadril/cirurgia , Acetábulo/cirurgia , Adolescente , Adulto , Artroplastia de Quadril/efeitos adversos , Feminino , Luxação Congênita de Quadril/classificação , Luxação Congênita de Quadril/diagnóstico por imagem , Prótese de Quadril , Humanos , Desigualdade de Membros Inferiores/cirurgia , Masculino , Pessoa de Meia-Idade , Osteotomia , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Falha de Prótese , Radiografia , Reoperação , Resultado do Tratamento , Adulto Jovem
8.
Zhonghua Wai Ke Za Zhi ; 53(2): 130-4, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25908287

RESUMO

OBJECTIVE: To analyze the results of pathogenic bacteria culture on chronic periprosthetic joint infection after total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: The medical data of 23 patients with chronic periprosthetic joint infection after TKA or THA from September 2010 to March 2014 were reviewed. Fifteen cases of TKA and 8 cases of THA were included in this study. There were 12 male and 11 female patients with the mean age of 62 years (range from 32 to 79 years), and among them 9 patients with sinus. All patients discontinued antibiotic therapy for a minimum of 2 weeks before arthrocentesis, taking pathogenic bacteria culture and antimicrobial susceptibility test by using synovial fluid taken preoperatively and intraoperatively of revision. Common pathogenic bacteria culture and pathological biopsy were taken on tissues intraoperatively of revision. Culture-negative specimens were prolonged the period of incubation for 2 weeks. RESULTS: The overall culture-positive rate of all 23 patients for 1 week before revision was 30.4% (7/23), and the positive rate of culture-negative samples which prolonged for 2 weeks was 39.1% (9/23). The overall culture-positive rate of patients for 1 week intraoperatively of revision was 60.9% (14/23), and the positive rate of culture-negative samples which prolonged for 2 weeks was 82.6% (19/23). The incubation results of 7 cases (30.4%) preoperatively conformed to that of intraoperation. CONCLUSION: The culture-positive rate of pathogenic bacteria culture can be increased evidently by discontinuing antimicrobial therapy for a minimum of 2 weeks prior to the definite diagnosis.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Bactérias/isolamento & purificação , Infecções Relacionadas à Prótese , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação
9.
Cancer Cell Int ; 14: 79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25788862

RESUMO

BACKGROUND: Aberrant DNA methylation is an acquired epigenetic alteration that serves as an alternative to genetic defects in the inactivation of tumor suppressor genes and other genes in diverse human cancers. Gastric carcinoma is one of the tumors with a high frequency of aberrant methylation in promoter region. Hence we investigated the promoter methylation status and expression level of HOXA11 gene which may involve in GC development. METHODS: Thirty-two surgical excised gastric cancer specimens, twelve paired adjacent non-cancerous specimens and seven normal gastric mucosas were examined. The methylation status and expression level of HOXA11 gene were determined by bisulfite sequencing polymerase chain reaction (BSP), real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) respectively. HOXA11 expression was knocked-down with siRNA to mimic HOXA11 gene hypermethylation and ability of cell proliferation and migration was determinate. In addition, we analyzed and correlated the findings with clinicopathological features. RESULTS: The methylation level of HOXA11 gene in gastric cancer tissues and adjacent non-cancerous tissues were higher than those in normal gastric mucosa (P < 0.05). The methylation level was higher in TNM III and IV patients of GC than those in TNM I and II patients (P < 0.05). The expression of HOXA11 mRNA and protein decreased in normal gastric mucosa, peri-cancer tissue and GC (P < 0.05). HOXA11 expression was inversely correlated with DNA methylation (P < 0.05). Knocked-down of HOXA11 expression with siRNA in BGC-823 cells enhanced cell proliferation compared with control, but no significant different was observed in migration ability. CONCLUSION: Hypermethylation and decreased expression of HOXA11 gene may be involved in the carcinogenesis and development of GC and may provide useful information for the prediction of the malignant behaviors of GC. And the expression of HOXA11 is impaired by DNA methylation. However, repression of HOXA11 expression promoted BGC-823 cell proliferation.

10.
Polymers (Basel) ; 16(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38891512

RESUMO

The application of hexanitrohexaazaisowurtzitane (HNIW) as an oxidizer in solid propellants aligns with the pursuit of high-energy materials. However, the phase transformation behavior and high impact sensitivity of HNIW are its limitations. Due to the strong adhesion and mild synthesis conditions, polydopamine (PDA) has been employed to modify HNIW. However, the method suffers from a slow coating process and a non-ideal coating effect under short reaction time. Herein, oxygen-accelerated dopamine in situ polymerization coating method was developed. It was found that oxygen not only reduced the coating time but also contributed to forming a dense and uniform PDA layer. HNIW@PDA coated in oxygen for 6 h exhibited the most favorable performance, with a delay of 20.8 °C in the phase transition temperature and a reduction of 145.45% in the impact sensitivity. The -OH groups on the surface of PDA enhanced the interaction between HNIW and polymer binders, resulting in a 20.36% reduction in the dewetting percentage. The lower content of PDA in HNIW@PDA (1.17%) resulted in minimal variation in the heat of explosion for HNIW@PDA-based HTPB propellant (6287 kJ/kg) in comparison to HNIW-based HTPB propellant (6297 kJ/kg). Hence, HNIW@PDA-based propellants are expected to offer an alternative with promising safety and mechanical performance compared to existing HNIW-based propellants, thus facilitating the application of HNIW in high-energy propellants. This work presents a low-cost method for efficiently inhibiting the phase transformation of polycrystalline explosives and reducing the impact sensitivity. It also offers a potential approach to enhance the interfacial interaction between nitro-containing explosives and polymer binders.

11.
Polymers (Basel) ; 16(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38543400

RESUMO

Glycidyl azide polymer (GAP)-based polyurethane is an ideal elastomeric matrix for high-energy, low-smoke, and insensitive solid propellants. As the skeleton structure of GAP propellants, changes in the structure and properties of GAP elastomers during aging lead to the deterioration of propellant performance (especially in relation to mechanical properties), which causes safety risks. A high-temperature-accelerated aging experiment (70 °C) on a GAP elastomer was conducted. The evolution of the microstructure of the GAP elastomer system was analyzed by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR), and variations in the macroscopic properties were analyzed by the hardness test and the uniaxial tensile test. The experimental results showed that thermal aging of the GAP elastomer is a coupled process of multiple chemical reactions. The azide groups, urethane groups, and ether bonds were the weak links in the network structure, breaking during the aging process, and the crosslinking density rose and then decreased. Macroscopic properties also showed segmented changes. The aging process was divided into three stages: post-curing (stage one); when the crosslinked network began to break (stage two), and when the crosslinked network was destroyed (stage three). Changes in the microstructure and macroscopic properties were consistent. This work is of great significance for exploring the aging mechanism of GAP propellants and extending their storage life.

12.
Plants (Basel) ; 13(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931077

RESUMO

Photosynthetic induction and stomatal kinetics are acknowledged as pivotal factors in regulating both plant growth and water use efficiency under fluctuating light conditions. However, the considerable variability in methodologies and light regimes used to assess the dynamics of photosynthesis (A) and stomatal conductance (gs) during light induction across studies poses challenges for comparison across species. Moreover, the influence of stomatal morphology on both steady-state and non-steady-state gs remains poorly understood. In this study, we show the strong impact of IRGA Chamber Illumination and Whole Plant Illumination on the photosynthetic induction of two rice species. Our findings reveal that these illuminations significantly enhance photosynthetic induction by modulating both stomatal and biochemical processes. Moreover, we observed that a higher density of smaller stomata plays a critical role in enhancing the stomatal opening and photosynthetic induction to fluctuating light conditions, although it exerts minimal influence on steady-state gs and A under constant light conditions. Therefore, future studies aiming to estimate photosynthetic induction and stomatal kinetics should consider the light environments at both the leaf and whole plant levels.

13.
Food Chem ; 399: 134017, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055068

RESUMO

Rice ratooning system is becoming increasingly important for food security in China, however, information on grain cadmium (Cd) and arsenic (As) levels is lacking. We collected grain samples of main crop (MC) and ratoon crop (RC) from five sites, where the same eleven varieties were planted, and determined the Cd and As concentration in brown rice. Results showed that differences in grain Cd level between MC and RC were inconsistent across experimental sites, although the average value was comparable. In contrast, the grain As level was significantly higher in MC than in RC by 99.8% on average, which was consistent across all sites. Moreover, there was a significant positive correlation in grain Cd concentration between RC and MC. Overall, RC-produced rice is safer than MC with dramatically lower As concentration, and planting rice varieties with low Cd accumulation capacity is important for production of safe rice in rice ratooning system.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Cádmio/análise , China , Grão Comestível/química , Solo , Poluentes do Solo/análise
14.
RSC Adv ; 13(10): 7020-7029, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36874934

RESUMO

Hydroxyl-terminated polybutadiene (HTPB) is a flexible telechelic compound with a main chain containing a slightly cross-linked activated carbon-carbon double bond and a hydroxyl group at the end. Therefore, in this paper, HTPB was used as a terminal diol prepolymer, and sulfonate AAS and carboxylic acid DMPA were used as hydrophilic chain extenders to prepare low-temperature adaptive self-matting waterborne polyurethane (WPU). Due to the fact that the non-polar butene chain in the HTPB prepolymer cannot form a hydrogen bond with the urethane group, and the solubility parameter difference between the hard segment formed by the urethane group is large, the gap of T g between the soft and hard segments of the WPU increases by nearly 10 °C, with more obvious microphase separation. At the same time, by adjusting the HTPB content, WPU emulsions with different particle sizes can be obtained, thereby obtaining WPU emulsions with good extinction properties and mechanical properties. The results show that HTPB-based WPU with a certain degree of microphase separation and roughness obtained by introducing a large number of non-polar carbon chains has good extinction ability, and the 60° glossiness can be as low as 0.4 GU. Meanwhile, the introduction of HTPB can improve the mechanical properties and low temperature flexibility of WPU. The T g,s (the glass transition temperature of soft segment) of WPU modified by the HTPB block decreased by 5.82 °C, and the ΔT g increased by 21.04 °C, indicating that the degree of microphase separation increased. At -50 °C, the elongation at break and tensile strength of WPU modified by HTPB can still maintain 785.2% and 76.7 MPa, which are 1.82 times and 2.91 times those of WPU with only PTMG as soft segment, respectively. The self-matting WPU coating prepared in this paper can meet the requirements of severe cold weather and has potential application prospects in the field of finishing.

15.
Front Plant Sci ; 13: 889542, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592562

RESUMO

Ratoon rice is proposed as a promising way to improve rice productivity via increasing harvest frequency. Nitrogen (N) is the most effective in promoting the development and growth of ratoon plants. However, limited information is available on how different N management practices affect the biomass production of the ratoon crop (RC) through influencing canopy light interception, radiation use efficiency (RUE), and N utilization. Field experiments were conducted in central China in 2016 and 2017 to examine the effects of N management practices on the biomass accumulation of RC and the underlying physiological mechanisms. The N rates (100 vs. 200 kg N ha-1) in the main crop (MC) had a small and inconsistent effect on the biomass accumulation of RC. N application at 15 days after heading of MC for promoting bud development (Nbud, 100 kg N ha-1) increased total biomass production of RC by 17.2-19.1%, due to the improvements in both pre- and post-heading biomass production during the ratoon season (BPratoon). N application at 1-2 days after harvesting of MC for promoting the growth of regenerated tillers (Ntiller, 100 kg N ha-1) increased total biomass production of RC by 7.8-15.9% due to the improvements in post-heading BPratoon alone or both pre- and post-heading BPratoon. The differences in BPratoon caused by Nbud and Ntiller were associated with crop growth rate, leaf area index, RUE, and N uptake of RC. Total N uptake of RC was improved by Nbud through increasing stubble N content at harvest of MC and by Ntiller through increasing plant N uptake during the ratoon season. N use efficiency for BPratoon was reduced by Ntiller but not by Nbud. These results suggest that both Nbud and Ntiller play important roles in improving biomass production in RC, although Nbud was more efficient than Ntiller.

16.
RSC Adv ; 12(35): 22806-22814, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36106003

RESUMO

Cu nanoparticles are more active catalytically than CuO nanoparticles, which have been widely studied as catalysts for organic synthesis, electrochemistry, and optics. However, Cu nanoparticles are easily agglomerated and oxidized in air. In this research, columnar, flower-like, bubble-like and teardrop-shaped Cu/GO nanocomposites were fabricated via a water-solvent thermal method and high temperature calcination technique using deionized water (H2O), methanol (CH3OH), ethanol (CH3CH2OH) and ethylene glycol (EG) as the solvent, respectively. The structures, the morphology and the catalytic performance and catalytic mechanism for thermal decomposition of ammonium perchlorate (AP) of the Cu/GO nanocomposites have been studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen adsorption tests (BET), simultaneous thermogravimetry-differential scanning calorimetry (TGA/DSC) and thermogravimetric couplet with Fourier transform infrared spectroscopy (TGA-FTIR), respectively. The experimental results show that the morphology of the Cu/GO nanocomposites has a significant effect on the surface area and the teardrop-shaped Cu/GO nanocomposites have the largest specific surface area and the best catalytic performance among them. When 5 wt% of the Cu/GO nanocomposites was added, the decomposition temperature of AP decreased from 426.3 °C to 345.5 °C and the exothermic heat released from the decomposition of AP increased from 410.4 J g-1 to 4159.4 J g-1. In addition, the four morphological Cu/GO nanocomposites exhibited good stability, their catalytic performance for thermal decomposition of AP remained stable after 1 month in air. Excellent catalytic performance and stability were attributed to the strong catalytic activity of pure metal nanoparticles, and GO can accelerate electron movement and inhibit the agglomeration of nanoparticles, as well as the multiple effects of inhibiting the oxidation of Cu nanoparticles in air. Therefore, it has important application potential in high-energy solid propellant.

17.
Zhonghua Yi Xue Za Zhi ; 91(11): 752-6, 2011 Mar 22.
Artigo em Zh | MEDLINE | ID: mdl-21600100

RESUMO

OBJECTIVE: To compare the early clinical outcomes of primary total knee arthroplasty by a fixed-bearing versus mobile-bearing prosthesis. METHODS: A total of 80 patients with osteoarthritis at our hospital from January 2008 to October 2008 were sequentially and randomly assigned into Group A (fixed-bearing prosthesis) (40 knees) and Group B (mobile-bearing prosthesis) (40 knees). And the data of the range of motion (ROM), Knee Society Score (KSS) and Western Ontario MacMaster (WOMAC) were collected at pre-operation and 6, 12 and 24 months post-operation respectively. RESULTS: The P values were as follows: KSS: 0.754, 0.802, 0.561, 0.764; HSS (Hospital for Special Surgery): 0.737, 0.361, 0.254, 0.330; WOMAC (Western Ontario and McMaster Universities) osteoarthritis index: 0.976, 0.557, 0.946, 0.818; ROM follow-up: 0.519, 0.646, 0.175, 0.276. No significant differences were found in clinical outcomes between two groups. CONCLUSION: The fixed-bearing and mobile-bearing prostheses show no difference in clinical outcomes.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Resultado do Tratamento
18.
Zhonghua Wai Ke Za Zhi ; 49(6): 551-7, 2011 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-21914309

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of tourniquet in total knee arthroplasty. METHOD: Studies on comparison between with and without tourniquet in total knee arthroplasty were identified from Medline, PubMed, EMASE, Cochrane Library, CBM, Highwire, CNKI, VIP, Articles Digital Periodicals.All the randomized controlled trials were included for meta-analysis with RevMan 4.2.2 software. RESULTS: Nineteen studies involving 15 in foreign languages, 4 in Chinese were identified. There were 1159 cases of knee replacement patients. The results of meta-analysis indicated that there were statistical difference between two groups on intraoperative blood loss (P = 0.000), the number of deep venous thrombosis (P = 0.020), thigh pain (P = 0.000), knee hematoma (P = 0.030), wound infection (P = 0.040), skin ecchymosis area (P = 0.000), and the increasing rate of knee circumference of 3 days after the operation (P = 0.000), while there were no statistical differences with respect to the total blood loss (P = 0.100), the number of blood transfusions (P = 0.150), operation time (P = 0.120), length of hospital stay (P = 0.350), the number of pulmonary embolism (P = 0.310), and skin blisters (P = 0.170). CONCLUSIONS: The tourniquet for total knee arthroplasty can reduce intraoperative blood loss, but can not reduce total blood loss and the number of blood transfusions transfusion, can not improve operative efficiency, can not shorten the hospitalization time and promote the knee joint functional recovery. Furthermore the tourniquet increases the probability of occurrence on deep vein thrombosis, wound infection, hematoma and ecchymosis knee, it also causes knee swelling and thigh pain. It suggests minimize to use tourniquet in total knee arthroplasty.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Torniquetes/efeitos adversos , Humanos , Segurança
19.
Front Plant Sci ; 12: 754790, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35185944

RESUMO

Plants are often confronted with light fluctuations from seconds to minutes due to altering sun angles, mutual shading, and clouds under natural conditions, which causes a massive carbon loss and water waste. The effect of stomatal morphology on the response of leaf gas exchange to fluctuating light remains disputable. In this study, we investigated the differences in leaf stomatal morphology and photosynthetic induction across twelve rice genotypes after a stepwise increase in light intensity. A negative correlation was observed between stomatal size and density across rice genotypes. Smaller and denser stomata contributed to a faster stomatal response under fluctuating light. Plants with faster stomatal opening also showed faster photosynthetic induction and higher biomass accumulation but lower intrinsic water use efficiency ( i WUE) under fluctuating light. Moreover, stomatal morphology seemed to have less effect on the initial and final stomatal conductance, and there was a minimal correlation between steady-state and non-steady-state stomatal conductance among different rice genotypes. These results highlight the important role of stomatal morphology in regulating photosynthetic efficiency and plant growth under fluctuating light conditions. To simultaneously enhance leaf i WUE when improving the photosynthetic efficiency under fluctuating light, it may be necessary to take biochemical processes into account in the future.

20.
Front Plant Sci ; 11: 26, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117372

RESUMO

Photosynthesis is highly sensitive to high temperature stress, and with the rising global temperature, it is meaningful to investigate the response of photosynthesis to growth temperature and its relationship with leaf anatomy plasticity. We planted 21 cultivars including eight indica cultivars, eight japonica cultivars, and five javanica cultivars in pot experiments under high growth temperature (HT, 38/28°C, day/night) and control treatment (CK, 30/28°C, day/night). Photosynthetic rate (A), stomatal conductance (gs ), transpiration rate (E), stomatal density (SD), vein density (VD), minor vein area (SVA), and major vein area (LVA) were measured after 30 treatment days. Results showed HT significantly increased A, gs , and E, while significantly decreased SD and LVA. There was no significant difference in A among the three subspecies both under CK and HT, while the javanica subspecies had higher gs , E, SVA, and LVA under HT, and the indica cultivars had higher VD and SD both under CK and HT. The javanica subspecies had higher relative value (HT/CK) of A, gs , and E, while difference was not observed in the relative value of SD, VD, and LVA among the three subspecies. The relative value of A was positively related to that of gs , while the latter was not correlated with the relative value of SD, VD, SVA, and LVA. Overall, the results suggested the increase of A and gs at HT was not attributed to leaf anatomy plasticity in respect of stomata and vein under HT.

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