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1.
J Nanobiotechnology ; 22(1): 8, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167113

RESUMO

Electroconductive hydrogels offer a promising avenue for enhancing the repair efficacy of spinal cord injuries (SCI) by restoring disrupted electrical signals along the spinal cord's conduction pathway. Nonetheless, the application of hydrogels composed of diverse electroconductive materials has demonstrated limited capacity to mitigate the post-SCI inflammatory response. Recent research has indicated that the transplantation of M2 microglia effectively fosters SCI recovery by attenuating the excessive inflammatory response. Exosomes (Exos), small vesicles discharged by cells carrying similar biological functions to their originating cells, present a compelling alternative to cellular transplantation. This investigation endeavors to exploit M2 microglia-derived exosomes (M2-Exos) successfully isolated and reversibly bonded to electroconductive hydrogels through hydrogen bonding for synergistic promotion of SCI repair to synergistically enhance SCI repair. In vitro experiments substantiated the significant capacity of M2-Exos-laden electroconductive hydrogels to stimulate the growth of neural stem cells and axons in the dorsal root ganglion and modulate microglial M2 polarization. Furthermore, M2-Exos demonstrated a remarkable ability to mitigate the initial inflammatory reaction within the injury site. When combined with the electroconductive hydrogel, M2-Exos worked synergistically to expedite neuronal and axonal regeneration, substantially enhancing the functional recovery of rats afflicted with SCI. These findings underscore the potential of M2-Exos as a valuable reparative factor, amplifying the efficacy of electroconductive hydrogels in their capacity to foster SCI rehabilitation.


Assuntos
Exossomos , Traumatismos da Medula Espinal , Ratos , Animais , Microglia/metabolismo , Exossomos/metabolismo , Hidrogéis/farmacologia , Traumatismos da Medula Espinal/metabolismo , Neurônios/metabolismo
2.
Plant Biotechnol J ; 21(3): 621-634, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36495424

RESUMO

More than half of the world's food is provided by cereals, as humans obtain >60% of daily calories from grains. Producing more carbohydrates is always the final target of crop cultivation. The carbohydrate partitioning pathway directly affects grain yield, but the molecular mechanisms and biological functions are poorly understood, including rice (Oryza sativa L.), one of the most important food sources. Here, we reported a prolonged grain filling duration mutant 1 (gfd1), exhibiting a long grain-filling duration, less grain number per panicle and bigger grain size without changing grain weight. Map-based cloning and molecular biological analyses revealed that GFD1 encoded a MATE transporter and expressed high in vascular tissues of the stem, spikelet hulls and rachilla, but low in the leaf, controlling carbohydrate partitioning in the stem and grain but not in the leaf. GFD1 protein was partially localized on the plasma membrane and in the Golgi apparatus, and was finally verified to interact with two sugar transporters, OsSWEET4 and OsSUT2. Genetic analyses showed that GFD1 might control grain-filling duration through OsSWEET4, adjust grain size with OsSUT2 and synergistically modulate grain number per panicle with both OsSUT2 and OsSWEET4. Together, our work proved that the three transporters, which are all initially classified in the major facilitator superfamily family, could control starch storage in both the primary sink (grain) and temporary sink (stem), and affect carbohydrate partitioning in the whole plant through physical interaction, giving a new vision of sugar transporter interactome and providing a tool for rice yield improvement.


Assuntos
Grão Comestível , Oryza , Proteínas de Plantas , Humanos , Grão Comestível/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Amido/metabolismo , Açúcares/metabolismo
3.
Med Sci Monit ; 29: e939711, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37231639

RESUMO

BACKGROUND Resistant starch is a novel type of dietary fiber that can be considered as a natural polymer carrier with potential development prospects in the field of oral colonic release preparations since it can be degraded by bacteria in the large intestine. MATERIAL AND METHODS In this study, oral resistant starch-drug-loaded microspheres were prepared by spraydrying, and the response surface method was used to optimize the process based on the encapsulation efficiency. RESULTS The optimal preparation process conditions for the resistant starch-aspirin-loaded microspheres were as follows: core material: wall material ratio of 1: 1.98, chitosan solution concentration of 1.98%, and spray drying air inlet temperature of 130.45°C resulted in a reliable entrapment efficiency of 68.96%. Infrared spectroscopy analysis indicated that the encapsulated aspirin-starch microspheres did not differ significantly from the original resistant starch material. The ultrastructure of the drug-loaded microspheres was evenly wrapped with the capsule core and appeared as smooth spheres. The combination of resistant starch, aspirin, and chitosan resulted in a cross-linking reaction that reduced the overall gelatinization temperature compared with the original starch material alone. The light transmittance of the drug-loaded microspheres was slightly higher than that of the original resistant starch, while digestibility was similar to that of the resistant starch, indicating that the release would exist in the environment of the large intestine. CONCLUSIONS This study provides pivotal insights into the development of resistant starch in the field of colonic release preparations.


Assuntos
Quitosana , Amido Resistente , Quitosana/química , Microesferas , Amido/química , Temperatura , Tamanho da Partícula
4.
Int J Mol Sci ; 24(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37762290

RESUMO

Rice lacks sufficient amounts of zinc despite its vitality for human health. Leaf senescence enables redistribution of nutrients to other organs, yet Zn retransfer during deficiency is often overlooked. In this hydroponic experiment, we studied the effect of Zn deficiency on rice seedlings, focusing on the fourth leaf under control and deficient conditions. Growth phenotype analysis showed that the growth of rice nodal roots was inhibited in Zn deficiency, and the fourth leaf exhibited accelerated senescence and increased Zn ion transfer. Analyzing differentially expressed genes showed that Zn deficiency regulates more ZIP family genes involved in Zn ion retransfer. OsZIP3 upregulation under Zn-deficient conditions may not be induced by Zn deficiency, whereas OsZIP4 is only induced during Zn deficiency. Gene ontology enrichment analysis showed that Zn-deficient leaves mobilized more biological pathways (BPs) during aging, and the enrichment function differed from that of normal aging leaves. The most apparent "zinc ion transport" BP was stronger than that of normal senescence, possibly due to Zn-deficient leaves mobilizing large amounts of BP related to lipid metabolism during senescence. These results provide a basis for further functional analyses of genes and the study of trace element transfer during rice leaf senescence.


Assuntos
Oryza , Oligoelementos , Humanos , Zinco , Oryza/genética , Envelhecimento , Íons
5.
Int J Mol Sci ; 24(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37372942

RESUMO

As the human population grows rapidly, food shortages will become an even greater problem; therefore, increasing crop yield has become a focus of rice breeding programs. The maize gene, ZmDUF1645, encoding a putative member of the DUF1645 protein family with an unknown function, was transformed into rice. Phenotypic analysis showed that enhanced ZmDUF1645 expression significantly altered various traits in transgenic rice plants, including increased grain length, width, weight, and number per panicle, resulting in a significant increase in yield, but a decrease in rice tolerance to drought stress. qRT-PCR results showed that the expression of the related genes regulating meristem activity, such as MPKA, CDKA, a novel crop grain filling gene (GIF1), and GS3, was significantly changed in the ZmDUF1645-overexpression lines. Subcellular colocalization showed that ZmDUF1645 was primarily localized on cell membrane systems. Based on these findings, we speculate that ZmDUF1645, like the OsSGL gene in the same protein family, may regulate grain size and affect yield through the cytokinin signaling pathway. This research provides further knowledge and understanding of the unknown functions of the DUF1645 protein family and may serve as a reference for biological breeding engineering to increase maize crop yield.


Assuntos
Secas , Oryza , Humanos , Oryza/metabolismo , Zea mays/genética , Zea mays/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Expressão Ectópica do Gene , Melhoramento Vegetal , Grão Comestível/genética , Grão Comestível/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
J Sci Food Agric ; 103(14): 7302-7313, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37499162

RESUMO

BACKGROUND: Chalkiness in rice reduces its market value and affects consumer acceptance. Research on the mechanism of chalkiness formation has focused primarily on the activity of key enzymes of carbon metabolism and starch accumulation. The relationship between the formation of chalkiness induced by N fertilizer and rice starch's multi-level structure and thermal properties still needs to be fully elucidated. RESULTS: In this study, the rates of chalky grains and degree of chalkiness decreased with the increase in N fertilizer dosage. This was attributed to an increased proportion of short chains, ordered structure carbon chains, small starch granules, and branched starches, and a higher degree of crystallinity and ΔHg in protein, and a decreased proportion of amylose, large starch granules, and weighted average diameter of starch granule surface area and volume. Application of N fertilizer promoted an increased proportion of short-branched chain amylopectin to develop a more ordered carbohydrate structure and crystalline lamella. These effects enhanced the normal development and compactness of starch granules in grains, and improved their arrangement morphology, thereby reducing the chalkiness in rice. CONCLUSION: These changes in starch multi-level structure and protein improve the physicochemical characteristics of starch and enhance the fullness, crystallinity and compactness of starch granules, while synergistically increasing the regularity and homogeneity of starch granules and thus optimizing the stacking pattern of starch granules, leading to a reduction in rice chalkiness under nitrogen fertilization and thus improving the appearance of rice. © 2023 Society of Chemical Industry.

7.
Environ Microbiol ; 23(10): 5946-5961, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33989446

RESUMO

Rice sheath blight caused by Rhizoctonia solani is the major disease of rice that seriously threatens food security worldwide. Efficient and eco-friendly biological approaches are urgently needed since no resistant cultivars are available. In this study, fallow and paddy soils were initially subjected to microbiome analyses, and the results showed that Talaromyces spp. were significantly more abundant in the paddy soil, while Trichoderma spp. were more abundant in the fallow soil, suggesting that Talaromyces spp. could live and survive better in the paddy soil. Five Talaromyces isolates, namely, TF-04, TF-03, TF-02, TF-01 and TA-02, were isolated from the paddy soil using sclerotia of R. solani as baits and were further evaluated for their activity against rice sheath blight. These isolates efficiently parasitized the hyphae and rotted the sclerotia even at higher water contents in the sterilized sand and the soil. Isolate TF-04 significantly promoted rice growth, reduced the severity of rice sheath blight and increased the rice yield under outdoor conditions. Defence-related genes were upregulated and enzyme activities were enhanced in rice treated with isolate TF-04. Our research supplies a microbiome-guided approach to screen biological control agents and provides Talaromyces isolates to biologically control rice sheath blight.


Assuntos
Microbiota , Oryza , Talaromyces , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Rhizoctonia , Solo , Talaromyces/genética
8.
Oncologist ; 25(1): e160-e169, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395751

RESUMO

BACKGROUND: This multicenter, open-label, phase Ib study investigated the safety and efficacy of binimetinib (MEK inhibitor) in combination with buparlisib (phosphatidylinositol 3-kinase [PI3K] inhibitor) in patients with advanced solid tumors with RAS/RAF alterations. MATERIALS AND METHODS: Eighty-nine patients were enrolled in the study. Eligible patients had advanced solid tumors with disease progression after standard therapy and/or for which no standard therapy existed. Evaluable disease was mandatory, per RECIST version 1.1 and Eastern Cooperative Oncology Group performance status 0-2. Binimetinib and buparlisib combinations were explored in patients with KRAS-, NRAS-, or BRAF-mutant advanced solid tumors until the maximum tolerated dose and recommended phase II dose (RP2D) were defined. The expansion phase comprised patients with epidermal growth factor receptor (EGFR)-mutant, advanced non-small cell lung cancer, after progression on an EGFR inhibitor; advanced RAS- or BRAF-mutant ovarian cancer; or advanced non-small cell lung cancer with KRAS mutation. RESULTS: At data cutoff, 32/89 patients discontinued treatment because of adverse events. RP2D for continuous dosing was buparlisib 80 mg once daily/binimetinib 45 mg twice daily. The toxicity profile of the combination resulted in a lower dose intensity than anticipated. Six (12.0%) patients with RAS/BRAF-mutant ovarian cancer achieved a partial response. Pharmacokinetics of binimetinib were not altered by buparlisib. Pharmacodynamic analyses revealed downregulation of pERK and pS6 in tumor biopsies. CONCLUSION: Although dual inhibition of MEK and the PI3K pathways showed promising activity in RAS/BRAF ovarian cancer, continuous dosing resulted in intolerable toxicities beyond the dose-limiting toxicity monitoring period. Alternative schedules such as pulsatile dosing may be advantageous when combining therapies. IMPLICATIONS FOR PRACTICE: Because dysregulation of the mitogen-activated protein kinase (MAPK) and the phosphatidylinositol 3-kinase (PI3K) pathways are both frequently involved in resistance to current targeted therapies, dual inhibition of both pathways may be required to overcome resistance mechanisms to single-agent tyrosine kinase inhibitors or to treat cancers with driver mutations that cannot be directly targeted. A study investigating the safety and efficacy of combination binimetinib (MEK inhibitor) and buparlisib (PI3K inhibitor) in patients harboring alterations in the RAS/RAF pathway was conducted. The results may inform the design of future combination therapy trials in patients with tumors harboring mutations in the PI3K and MAPK pathways.


Assuntos
Aminopiridinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/uso terapêutico , Morfolinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Critérios de Avaliação de Resposta em Tumores Sólidos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Invest New Drugs ; 38(6): 1774-1783, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32410080

RESUMO

Background Overcoming resistance to anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) in patients with KRAS wildtype (WT) metastatic colorectal cancer (mCRC) could help meet the needs of patients with limited treatment options. Methods In this phase 1b study, patients with N/KRAS WT, MET-positive mCRC who had progressed following anti-EGFR mAb treatment received escalating oral doses of capmatinib (150, 300, and 400 mg) twice daily plus weekly intravenous cetuximab (at the approved dose). The primary objective was to establish a recommended dose for expansion (RDE) of capmatinib in combination with cetuximab. Safety, preliminary activity, pharmacokinetics, and pharmacodynamics were also explored. Results Thirteen patients were enrolled. No patients experienced a dose-limiting toxicity at investigated doses; the RDE was established as capmatinib 400 mg twice daily plus cetuximab. All patients experienced adverse events (AEs) suspected to be related to the study treatment. Five patients (38.5%) reported study-drug-related AEs of grade 3/4 in severity. No patients achieved a complete or partial response according to RECIST v1.1; however, tumor shrinkage of 29-44% was observed in 4 patients. Conclusions Capmatinib plus cetuximab was well tolerated. Preliminary signs of activity were observed. Further investigation is warranted to obtain efficacy data and refine predictive biomarkers of response. Clinical trial registration NCT02205398.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Benzamidas/administração & dosagem , Cetuximab/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Imidazóis/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Triazinas/administração & dosagem , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Benzamidas/efeitos adversos , Benzamidas/farmacocinética , Linhagem Celular Tumoral , Cetuximab/efeitos adversos , Cetuximab/farmacocinética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Imidazóis/efeitos adversos , Imidazóis/farmacocinética , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas c-met/metabolismo , Critérios de Avaliação de Resposta em Tumores Sólidos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Triazinas/efeitos adversos , Triazinas/farmacocinética , Proteínas ras/genética
10.
Opt Express ; 24(1): 699-707, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26832299

RESUMO

Flexible vertical InGaN micro-light emitting diode (micro-LED) arrays have been fabricated and characterized for potential applications in flexible micro-displays and visible light communication. The LED epitaxial layers were transferred from initial sapphire substrates to flexible AuSn substrates by metal bonding and laser lift off techniques. The current versus voltage characteristics of flexible micro-LEDs degraded after bending the devices, but the electroluminescence spectra show little shift even under a very small bending radius 3 mm. The high thermal conductivity of flexible metal substrates enables high thermal saturation current density and high light output power of the flexible micro-LEDs, benefiting the potential applications in flexible high-brightness micro-displays and high-speed visible light communication. We have achieved ~40 MHz modulation bandwidth and 120 Mbit/s data transmission speed for a typical flexible micro-LED.

11.
Int Orthop ; 40(4): 827-34, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26112873

RESUMO

PURPOSE: To test whether a novel guide template we designed can facilitate accurate insertion of antegrade lag screws in the fixation of acetabular posterior column fractures. METHODS: We created virtual three-dimensional reconstruction models of the pelvis from CT scan data obtained from 96 adult patients without any bony problems. A virtual cylindrical implant was placed along the longitudinal axis of the acetabular posterior column passing through the ischial tuberosity. The diameter of cylindrical implant was augmented to 6.5 mm, and the direction was adjusted until the optimal screw path was found using the reverse engineering technique. The orifice of this cylinder from the iliac fossa was determined as the entry point for the antegrade lag screw. The anatomical parameters of the screw entry path were measured and saved in .stl format. The guide template was designed according to the acetabular morphology and the measured anatomical parameters before it was put into manufacture of a solid template with the rapid prototyping technique. The feasibility and accuracy of the guide template were tested in cadaveric pelvises. Finally, the guide template was used in real surgery for five patients. Furthermore, the time required for surgery was recorded. RESULTS: Under the guide of this navigation template, antegrade lag screws were successfully placed in the posterior column of the acetabulum in the cadaveric test. And five lag screws were successfully placed in five patients. The mean time of antegrade lag screw insertion required 5.8 (3-10) min. CONCLUSIONS: Antegrade lag screws can be more accurately put into the posterior column of the acetabulum with the help of this navigation template.


Assuntos
Acetábulo/cirurgia , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Técnicas Estereotáxicas/instrumentação , Acetábulo/diagnóstico por imagem , Acetábulo/lesões , Adulto , Parafusos Ósseos , Simulação por Computador , Desenho de Equipamento , Feminino , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Cirurgia Assistida por Computador , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
12.
Zhonghua Yi Xue Za Zhi ; 94(14): 1080-2, 2014 Apr 15.
Artigo em Zh | MEDLINE | ID: mdl-24851892

RESUMO

OBJECTIVE: To evaluate the imaging efficacies after Salter innominate osteotomy for developmental dysplasia of the hip (DDH). METHODS: A total of 51 DDH patients with 70 hips were recruited between March 2011 to August 2012. All of them underwent Salter innominate osteotomy. Preoperative radiographs including acetabular index (AI), sharp angle (SA), obturator angle and obturator height were measured. And postoperative radiographs were taken at 2 days, 3 months, 6 months and 1 year to measure the parameters of AI, sharp acetabular angle, obturator angle, obturator height, shifting index and descending angle of distal iliac end. Paired t test was used for statistical analyses. RESULTS: The average correction of AI was 35.5° ± 2.3° preoperatively versus 14.6° ± 1.6° postoperatively ( P = 0.000) . The average correction of Sharp angle was 50.6° ± 3.7° preoperatively versus 33.1° ± 3.2° postoperatively (P = 0.000) . The average correction of obturator angle was 58.3° ± 3.9° preoperatively versus 39.5° ± 2.8° postoperatively (P = 0.000) . The average correction of obturator height was (1.65 ± 0.26) cm preoperatively versus (1.10 ± 0.14) cm postoperatively (P = 0.000) . At 3 months, 6 months and 1 year post-operation, the average values of AI, SA, obturator angle and obturator height continued to fall. Both of them showed statistical improvement. Shifting index and descending angle of distal iliac end were 30.1% ± 3.6% and 31.3° ± 4.1° on average. Six (8.57%) Shenton lines were bad. CONCLUSIONS: The imaging evaluations of acetabulum and pelvis show marked improvements until 1 year in DDH patients after Salter innominate osteotomy. It provides data reference for operative evaluations through measuring the imaging parameters of truncation bone.


Assuntos
Diagnóstico por Imagem , Luxação Congênita de Quadril/diagnóstico , Feminino , Luxação Congênita de Quadril/cirurgia , Humanos , Masculino , Osteotomia/métodos , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
13.
J Mech Behav Biomed Mater ; 157: 106660, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39033558

RESUMO

Enhancing friction force in lubricated, compliant contacts is of particular interest due to its wide application in various engineering and biological systems. In this study, we have developed bioinspired surfaces featuring film-terminated ridges, which exhibit a significant increase in lubricated friction force compared to flat samples. We propose that the enhanced sliding friction can be attributed to the energy dissipation at the lubricated interface caused by elastic hysteresis resulting from cyclic terminal film deformation. Furthermore, increasing inter-ridge spacing or reducing terminal film thickness are favorable design criteria for achieving high friction performance. These findings contribute to our understanding of controlling lubricated friction and provide valuable insights into surface design strategies for novel functional devices.

14.
Foods ; 13(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38540845

RESUMO

The important reason for the commercial value of hybrid rice suffering is due to excessive chalkiness, and the biosynthesis of starch and proteins is critical for regulating chalkiness; however, it is currently unclear how the application of N fertilizer affects grains to reduce their chalkiness and improve their quality. The 2019, 2020, and 2021 trials were conducted in a split-plot design, with high and low chalky varieties as the main plot and N fertilizer rate as the split-plot. The effects of fertilization with 75, 150, and 225 kg N ha-1 on the dynamic synthesis of starch, protein, and endogenous hormones and on the amino acid of hybrid indica rice kernels with different degrees of chalkiness were investigated. Grain physiological activity was higher in low-chalky varieties than in high-chalky varieties, and these physiological parameters were strongly associated with chalkiness formation. Higher N fertilization (150 and 225 kg N ha-1) significantly reduced the proportion of chalky grains (8.93-28.02%) and chalkiness (8.61-33.99%) compared with 75 kg N ha-1. Increased N fertilization decreased the activities of granule-bound starch synthase and starch-debranching enzyme, but significantly increased adenosine diphosphate glucose pyrophosphorylase, soluble starch synthase, and starch-branching enzyme activities, synergistically improving glutamate synthetase and glutamine synthetase enzyme activities, which tended to support the synthesis of amylopectin, α-ketoglutarate, and 3-phosphoglyceric acid-derived amino acids in the endosperm cells of the grains; this favored starch and protein accumulation in the grains at 6-30 days after anthesis. Additionally, N application promoted the synthesis of endogenous hormones 1-aminocyclopropane-1-carboxylic acid, gibberellins, and abscisic acid in grains. Hence, N fertilization reduced the rice chalkiness in hybrid indica rice varieties by balancing grain protein and starch composition and enhancing some endogenous hormone synthesis.

15.
Front Plant Sci ; 15: 1400146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799091

RESUMO

Introduction: The use of controlled-release nitrogen (N) fertilizers has been shown to improve yield and N-use efficiency (NUE) in mechanical transplanted rice. However, the fertilizer requirements for mechanical direct-seeding rice differ from those for mechanical transplanted rice. The effects of controlled-release fertilizers on yield, NUE, and quality in mechanical direct-seeding rice are still unknown. Methods: Hybrid indica rice varieties Yixiangyou 2115 and Fyou 498 were used as test materials, and slow-mixed N fertilizer (120 kg hm-2) as a base (N1), N1+urea-N (30 kg hm-2) once as a base (N2), N1+urea-N (30 kg hm-2) topdressing at the tillering stage (N3), N1+urea-N (30 kg hm-2) topdressing at the booting stage (N4) four N fertilizer management to study their impact on the yield, NUE and quality of mechanical direct-seeding rice. Results and discussion: Compared with Yixiangyou 2115, Fyou 498 significantly increased photosynthetic potential, population growth rate, root vigor, and N transport rate by 3.34-23.88%. This increase further resulted in a significant improvement in the yield and NUE of urea-N topdressing by 1.73-5.95 kg kg-1. However, Fyou 498 showed a significant decrease in the head rice rate and taste value by 3.34-7.67%. All varieties were treated with N4 that significantly increase photosynthetic potential and population growth rate by 15.41-62.72%, reduce the decay rate of root vigor by 5.01-21.39%, promote the N transport amount in stem-sheaths (leaves) by 13.54-59.96%, and then significantly increase the yields by 4.45-20.98% and NUE of urea-N topdressing by 5.20-45.56 kg kg-1. Moreover, the rice processing and taste values were optimized using this model. Correlation analysis revealed to achieve synergistic enhancement of high-yield, high-quality, and high-NUE in rice, it is crucial to focus on increasing photosynthetic potential, population growth rate, and promoting leaf N transport. Specifically, increasing the contribution rate of N transport in stem-sheaths is the most important. These findings offer an effective N management strategy for 4R nutrient stewardship (right source, right method, right rate and right timing) of mechanical direct-seeding hybrid indica rice.

16.
Opt Express ; 21(7): 8444-9, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23571934

RESUMO

The performance of nitride-based LEDs was improved by inserting dual stage and step stage InGaN/GaN strain relief layer (SRL) between the active layer and n-GaN template. The influences of step stage InGaN/GaN SRL on the structure, electrical and optical characteristics of GaN-based LEDs were investigated. The analysis of strain effect on recombination rate based k·p method indicated 12.5% reduction of strain in InGaN/GaN MQWs by inserting SRL with step stage InGaN/GaN structures. The surface morphology was improved and a smaller blue shift in the electroluminescence (EL) spectral with increasing injection current was observed for LEDs with step stage SRL compared with conventional LEDs. The output power of LEDs operating at 20 mA was about 15.3 mW, increased by more than 108% by using step stage InGaN/GaN SRL, which shows great potential of such InGaN/GaN SRL in modulating InGaN/GaN MQWs optical properties based on its strain relief function.


Assuntos
Gálio/química , Índio/química , Iluminação/instrumentação , Semicondutores , Cor , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Estresse Mecânico
17.
Zhonghua Zhong Liu Za Zhi ; 35(7): 534-9, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24257308

RESUMO

OBJECTIVE: To summarize the experiences in gallbladder cancer treatment, evaluate the efficacy of postoperative radiotherapy, and investigate the method of improving the survival of gallbladder cancer patients. METHODS: One hundred and twenty-seven gallbladder cancer patients, treated in our center by radical resection (84 cases) and combined with postoperative radiotherapy (43 cases), between June 2003 to December 2009 were included in this study. Their clinical data and follow-up results were retrospectively analyzed. According to AJCC staging criteria, the survival time and 1-, 3- and 5-year survival rates of the surgery group and the postoperative radiotherapy group at the different pathological stages and resection margin status were compared. RESULTS: The median survival time of postoperative radiotherapy patients in stage III was 16.9 months, and the 1-year, 3-year, and 5-year survival rates were 55.7%, 23.5% and 18.2%, respectively, significantly higher than that of the simple operation group ( median survival time 14.3 months, and 1-year, 3-year, 5-year survival rates 42.7%, 22.6% and 16.7%, respectively) (P<0.05). The median survival time of postoperative radiotherapy patients in stage IV, the median survival time was 9.7 months in the postoperative radiotherapy group and 6.3 months in the simple surgery group, and the 1-year survival rates were 14.2% and 9.8%, the 3-year survival rates were 7.2% and 3.9%, the 5-year survival rates were 7.2% and 1.9%, respectively, all showing a statistically significant difference (P<0.05). Among the stage III and IVpatients, all the 1-, 3- and 5-year survival rates of the postoperative radiotherapy group were higher than that of the simple R0 and R1 surgical resection group (all P<0.05), but with a non-significant difference between the stageIandIIpatients (P>0.05). The main side effects in postoperative radiotherapy patients including nausea, vomiting and abdominal pain, all were successfully alleviated by symptomatic and supportive therapy, and the radiotherapy was successfully completed. CONCLUSIONS: With regard to the gallbladder cancer patients in stage III and IV, the survival rate can be obviously increased by postoperative radiotherapy. However, for patients in stageIand II, whether postoperative radiotherapy significantly improves the survival or not, needs to be further validated in larger scale studies.


Assuntos
Colecistectomia/métodos , Neoplasias da Vesícula Biliar/radioterapia , Neoplasias da Vesícula Biliar/cirurgia , Radioterapia Conformacional , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Estadiamento de Neoplasias , Radioterapia Adjuvante/efeitos adversos , Radioterapia Conformacional/efeitos adversos , Estudos Retrospectivos , Taxa de Sobrevida , Vômito/etiologia
18.
Plants (Basel) ; 12(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37765500

RESUMO

Plant height is an important agronomic trait associated with plant architecture and grain yield in rice (Oryza sativa L.). In this study, we report the identification of quantitative trait loci (QTL) for plant height using a chromosomal segment substitution line (CSSL) population with substituted segments from japonica variety Nipponbare (NIP) in the background of the indica variety 9311. Eight stable QTLs for plant height were identified in three environments. Among them, six loci were co-localized with known genes such as semidwarf-1 (sd1) and Grain Number per Panicle1 (GNP1) involved in gibberellin biosynthesis. A minor QTL qPH8.2 on chromosome 8 was verified and fine-mapped to a 74 kb region. Sequence comparison of the genomic region revealed the presence/absence of a 42 kb insertion between NIP and 9311. This insertion occurred predominantly in temperate japonica rice. Comparisons on the near-isogenic lines showed that the qPH8.2 allele from NIP exhibits pleiotropic effects on plant growth, including reduced plant height, leaf length, photosynthetic capacity, delayed heading date, decreased yield, and increased tiller angle. These results indicate that qPH8.2 from temperate japonica triggers adverse effects on plant growth and yield when introduced into the indica rice, highlighting the importance of the inter-subspecies crossing breeding programs.

19.
Front Plant Sci ; 14: 1170739, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223819

RESUMO

Introduction: To investigate the effects of no-tillage with straw mulching on the absorption and utilization of soil nitrogen (N), fertilizer N, and straw N by rice under paddy-upland rotations. Methods: A field experiment with three cropping systems: fallow-rice rotation without straw mulching (FRN), wheat-rice rotation with wheat mulching in rice season (WRS), and oilseed rape-rice rotation with oilseed rape straw mulching in rice season (ORS) was conducted from 2015 to 2017, along with a mini-plot experiment with 15N-labeled urea and straws, which was conducted in 2017. Results: No-tillage with straw reduced rice N uptake up to 20 days after transplanting, the total amount of fertilizer N uptake of WRS and ORS rice plants was 46.33 and 61.67 kg/ha, respectively, which was 9.02 and 45.10% higher than that of FRN plants. Soil N was the main source for rice growth, followed by fertilizer N. Soil N uptake by WRS and ORS rice plants was 21.75 and 26.82% higher than that of FRN plants, accounting for 72.37 and 65.47%, respectively, of the total N accumulated in rice plants. Straw mulching increased the N utilization efficiency of tillering, panicle, and total fertilizer by 2.84-25.30%; however, base fertilizer was dependent on straw mulching. The total amount of N released from WRS and ORS straw mulching in the rice season was 34.97 and 24.82 kg/ha, respectively; however, only 3.04 and 4.82% of it was absorbed by the rice plants, accounting for only 0.62 and 0.66% of the total accumulated N. Discussion: No-tillage with straw mulching under paddy-upland rotations increased the N utilization of rice, especially for the absorption of soil N. These results provide theoretical information for the effective utilization of straw and rational N application practices in rice-based cropping systems.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36752284

RESUMO

Recent breakthroughs in cell transplantation therapy have revealed the promising potential of bone marrow mesenchymal stem cells (BMSCs) for promoting the regeneration of growth plate cartilage injury. However, the high apoptosis rate and the uncertainty of the differentiation direction of cells often lead to poor therapeutic effects. Cells are often grown under three-dimensional (3D) conditions in vivo, and the stiffness and components of the extracellular matrix (ECM) are important regulators of stem cell differentiation. To this end, a 3D cartilage-like ECM hydrogel with tunable mechanical properties was designed and synthesized mainly from gelatin methacrylate (GM) and oxidized chondroitin sulfate (OCS) via dynamic Schiff base bonding under UV. The effects of scaffold stiffness and composition on the survival and differentiation of BMSCs in vitro were investigated. A rat model of growth plate injury was developed to validate the effect of the GMOCS hydrogels encapsulated with BMSCs on the repair of growth plate injury. The results showed that 3D GMOCS hydrogels with an appropriate modulus significantly promoted chondrogenic differentiation of BMSCs, and GMOCS/BMSC transplantation could effectively inhibit bone bridge formation and promote the repair of damaged growth plates. Accordingly, GMOCS/BMSC therapy can be engineered as a promising therapeutic candidate for growth plate injury.

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