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1.
BMC Plant Biol ; 24(1): 189, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38486149

RESUMEN

BACKGROUND: Growing evidence demonstrates that the synergistic interaction of far-red light with shorter wavelength lights could evidently improve the photosynthesis efficiency of multiple species. However, whether/how far-red light affects sink organs and consequently modulates the source‒sink relationships are largely unknown. RESULTS: Here, equal intensities of white and far-red lights were added to natural light for grape plantlets to investigate the effects of far-red light supplementation on grapevine growth and carbon assimilate allocation, as well as to reveal the underlying mechanisms, through physiological and transcriptomic analysis. The results showed that additional far-red light increased stem length and carbohydrate contents in multiple organs and decreased leaf area, specific leaf weight and dry weight of leaves in comparison with their counterparts grown under white light. Compared to white light, the maximum net photosynthetic rate of the leaves was increased by 31.72% by far-red light supplementation, indicating that far-red light indeed elevated the photosynthesis efficiency of grapes. Transcriptome analysis revealed that leaves were most responsive to far-red light, followed by sink organs, including stems and roots. Genes related to light signaling and carbon metabolites were tightly correlated with variations in the aforementioned physiological traits. In particular, VvLHCB1 is involved in light harvesting and restoring the balance of photosystem I and photosystem II excitation, and VvCOP1 and VvPIF3, which regulate light signal transduction, were upregulated under far-red conditions. In addition, the transcript abundances of the sugar transporter-encoding genes VvSWEET1 and VvSWEET3 and the carbon metabolite-encoding genes VvG6PD, VvSUS7 and VvPGAM varied in line with the change in sugar content. CONCLUSIONS: This study showed that far-red light synergistically functioning with white light has a beneficial effect on grape photosystem activity and is able to differentially affect the growth of sink organs, providing evidence for the possible addition of far-red light to the wavelength range of photosynthetically active radiation (PAR).


Asunto(s)
Clorofila , Luz Roja , Clorofila/metabolismo , Transcriptoma , Fotosíntesis , Azúcares , Carbono
2.
J Org Chem ; 89(9): 6149-6158, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38635972

RESUMEN

The detailed mechanism of transition metal-free-catalyzed monomethylation of 2-naphthyl acetonitrile (1a) with CO2 in the presence of triazabicyclodecene (TBD) and BH3NMe3 was investigated using density functional theory. The C-methylation process proved to generate formaldehyde followed by the formation of the product via an alcohol rather than a methoxyborane intermediate. During the reaction, CO2 is activated to form the TBD-CO2 adduct and BH3NMe3 is changed into TBD-BH2 (IM2) in the presence of TBD. IM2 plays a real reducing role within the system due to the unique coordination capability of the B atom. In addition to enhancing the nucleophilicity of 1a through deprotonation by tBuOK, our research also indicates that the generated tBuOH not only assists in proton transfer to generate an alcohol intermediate but also promotes the regeneration of TBD.

3.
Oecologia ; 205(1): 69-80, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38683388

RESUMEN

Hard limestone substrates, which are extensively distributed, are believed to exacerbate drought and increase the difficulty of restoration in vulnerable karst regions. Fissures in such substrates may alleviate the negative effect of drought on plants, but the underlying mechanisms remain poorly understood. In a two-way factorial block design, the growth and photosynthesis of 2-year-old Phoebe zhennan seedlings were investigated in two water availabilities (high versus low) and three stimulated fissure habitat groups (soil, soil-filled fissure and non-soil-filled fissure). Moreover, the fissure treatments included both small and big fissures. Compared to the soil group, the non-soil-filled fissure group had decreased the total biomass, root biomass, total root length, and the root length of fine roots in the soil layer at both water availabilities, but increased net photosynthetic rate (Pn) and retained stable water use efficiency (WUE) at low water availability. However, there were no significant differences between the soil-filled fissure group and soil group in the biomass accumulation and allocation as well as Pn. Nevertheless, the SF group decreased the root distribution in total and in the soil layer, and also increased WUE at low water availability. Across all treatments, fissure size had no effect on plant growth or photosynthesis. Karst fissures filled with soil can alleviate drought impacts on plant root growth, which involves adjusting root distribution strategies and increasing water use efficiency. These results suggest that rock fissures can be involved in long-term plant responses to drought stress and vegetation restoration in rocky mountain environments under global climate change.


Asunto(s)
Sequías , Fotosíntesis , Suelo , Biomasa , Agua , Raíces de Plantas/crecimiento & desarrollo , Ecosistema
4.
Phys Chem Chem Phys ; 26(4): 3069-3080, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38180441

RESUMEN

The binary T-X phase diagram of salicylic acid (SA) and 4-hydroxybenzoic acid (4HBA) has been constructed from 20 °C to melting, revealing a partially miscible system with an eutectic composition of 27.3 mol% 4HBA in SA. Terminal crystalline solid solutions were obtained at the extremes of the phase diagram with solid-state miscibility limits below 0.4% at 20 °C. The limited phase boundaries could be captured experimentally by both DSC analyses at around melting temperature and solid-liquid equilibria studies at 20 °C in two solvent systems. The NRTL model was applied to regress phase boundaries and generate the final binary T-X phase diagram. The NRTL model was also used to regress solubility data, and reproduce the ternary SA/4HBA/solvent phase diagram at 20 °C and 1 atm. 4HBA was obtained as two crystal forms, viz. anhydrate and monohydrate. It is shown how the monohydrate of 4HBA is less miscible with SA in the solid state than the anhydrous form of 4HBA. As compared to pure SA and 4HBA, the crystalline solid solutions exhibited significant changes in physical properties that are relevant for organic and pharmaceutical materials in the context of impurity effects. A lattice incorporation of just 0.2 mol% 4HBA in SA caused a 10% reduction in melting enthalpy and a 66% solubility increase in 40 wt% MeOH in H2O. The reasons for this thermodynamic effect are discussed.

5.
Environ Res ; 246: 118079, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38160967

RESUMEN

Remanufacturing has attracted much attention for its enormous potential in resource recycling and low-carbon emission reduction. To investigate the effects of different government intervention policies on remanufacturing and carbon emissions, two profit maximization models of the capital-constrained manufacturer under carbon tax and low-carbon credit policies are constructed respectively. Then, through theoretical and numerical analyses, some significant findings are drawn: (1) Both carbon tax and low-carbon credit policies can encourage capital-constrained manufacturers to produce more remanufactured products, but which intervention policy is more advantageous also depends on the carbon emission cost of new products or financing cost of the remanufactured products. (2) Although carbon tax policy can effectively control carbon emissions, it is always at the expense of both capital-constrained manufacturers and consumers; while low-carbon credit policy can help capital-constrained manufacturers achieve the goal of win-win economic and environmental benefits when the remanufacturing carbon savings advantages are more apparent. (3) From the perspective of consumer benefits, carbon tax is more advantageous when the consumer willingness to pay for remanufactured products is higher; otherwise, low-carbon credit policy should be implemented. (4) The higher the environmental damage coefficient is, the more it can highlight the advantages of the two intervention policies in social welfare enhancement, especially the carbon tax policy; and when the environmental damage coefficient is given, the stronger the consumers' willingness to pay for remanufactured products is, the more it is conducive to reducing the negative effects caused by the carbon tax or low-carbon credit policy in social welfare enhancement, or increasing the corresponding positive effects. Based on above findings, some managerial insights and policy implications are provided to capital-constrained manufacturers and policy-makers.


Asunto(s)
Carbono , Políticas , Costos y Análisis de Costo , Gobierno , Reciclaje , Comercio
6.
Phys Rev Lett ; 131(17): 176401, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955469

RESUMEN

The disorder systems host three types of fundamental quantum states, known as the extended, localized, and critical states, of which the critical states remain being much less explored. Here we propose a class of exactly solvable models which host a novel type of exact mobility edges (MEs) separating localized states from robust critical states, and propose experimental realization. Here the robustness refers to the stability against both single-particle perturbation and interactions in the few-body regime. The exactly solvable one-dimensional models are featured by a quasiperiodic mosaic type of both hopping terms and on-site potentials. The analytic results enable us to unambiguously obtain the critical states which otherwise require arduous numerical verification including the careful finite size scalings. The critical states and new MEs are shown to be robust, illustrating a generic mechanism unveiled here that the critical states are protected by zeros of quasiperiodic hopping terms in the thermodynamic limit. Further, we propose a novel experimental scheme to realize the exactly solvable model and the new MEs in an incommensurate Rydberg Raman superarray. This Letter may pave a way to precisely explore the critical states and new ME physics with experimental feasibility.

7.
Phys Rev Lett ; 131(14): 146602, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37862668

RESUMEN

The Dirac material ZrTe_{5} at very low carrier density was recently found to be a nodal-line semimetal, where ultraflat bands are expected to emerge in magnetic fields parallel to the nodal-line plane. Here, we report that in very low carrier-density samples of ZrTe_{5}, when the current and the magnetic field are both along the crystallographic a axis, the current-voltage characteristics presents a pronounced nonlinearity which tends to saturate in the ultra quantum limit. The magnetic-field dependence of the nonlinear coefficient is well explained by the Boltzmann theory for flat-band transport, and we argue that this nonlinear transport is likely due to the combined effect of flat bands and charge puddles; the latter appear due to very low carrier densities.

8.
Ann Bot ; 132(5): 1033-1050, 2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-37850481

RESUMEN

Anthocyanin composition is responsible for the red colour of grape berries and wines, and contributes to their organoleptic quality. However, anthocyanin biosynthesis is under genetic, developmental and environmental regulation, making its targeted fine-tuning challenging. We constructed a mechanistic model to simulate the dynamics of anthocyanin composition throughout grape ripening in Vitis vinifera, employing a consensus anthocyanin biosynthesis pathway. The model was calibrated and validated using six datasets from eight cultivars and 37 growth conditions. Tuning the transformation and degradation parameters allowed us to accurately simulate the accumulation process of each individual anthocyanin under different environmental conditions. The model parameters were robust across environments for each genotype. The coefficients of determination (R2) for the simulated versus observed values for the six datasets ranged from 0.92 to 0.99, while the relative root mean square errors (RRMSEs) were between 16.8 and 42.1 %. The leave-one-out cross-validation for three datasets showed R2 values of 0.99, 0.96 and 0.91, and RRMSE values of 28.8, 32.9 and 26.4 %, respectively, suggesting a high prediction quality of the model. Model analysis showed that the anthocyanin profiles of diverse genotypes are relatively stable in response to parameter perturbations. Virtual experiments further suggested that targeted anthocyanin profiles may be reached by manipulating a minimum of three parameters, in a genotype-dependent manner. This model presents a promising methodology for characterizing the temporal progression of anthocyanin composition, while also offering a logical foundation for bioengineering endeavours focused on precisely adjusting the anthocyanin composition of grapes.


Asunto(s)
Vitis , Vino , Vitis/genética , Antocianinas/análisis , Antocianinas/metabolismo , Frutas/genética , Frutas/metabolismo , Vino/análisis
9.
Nanotechnology ; 34(22)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36808905

RESUMEN

Molecular dynamics simulation is used to study the transport characteristics of NaCl solution in boron nitride nanotubes (BNNTs). It presents an interesting and well-supported MD study of the crystallization of NaCl from its water solution under the confinement of a 3 nm thick boron nitride nanotube with varied surface charging conditions. The results of the molecular dynamics simulation indicate that NaCl crystallization occurs in charged BNNTs at room temperature when the concentration of NaCl solution reaches about 1.2 M. The reason for this phenomenon is as follows: when the number of ions in the nanotubes is high, the double electric layer that forms at the nanoscale near the charged wall surface, the hydrophobicity of BNNTs, and the interaction among ions cause ions to aggregate in the nanotubes. As the concentration of NaCl solution increases, the concentration of ions when they aggregate in the nanotubes reaches the saturation concentration of the NaCl solution, resulting in the crystalline precipitation phenomenon.

10.
Molecules ; 28(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37687118

RESUMEN

The ethylenediamine-N,N'-disuccinic acid (EDDS) was utilized to form Fe-EDDS complex to activate peroxymonosulfate (PMS) in the electrochemical (EC) co-catalytic system for effective oxidation of naphthenic acids (NAs) under neutral pH conditions. 1-adamantanecarboxylic acid (ACA) was used as a model compound to represent NAs, which are persistent pollutants that are abundantly present in oil and gas field wastewater. The ACA degradation rate was significantly enhanced in the EC/PMS/Fe(III)-EDDS system (96.6%) compared to that of the EC/PMS/Fe(III) system (65.4%). The addition of EDDS led to the formation of a stable complex of Fe-EDDS under neutral pH conditions, which effectively promoted the redox cycle of Fe(III)-EDDS/Fe(II)-EDDS to activate PMS to generate oxidative species for ACA degradation. The results of quenching and chemical probe experiments, as well as electron paramagnetic resonance (EPR) analysis, identified significant contributions of •OH, 1O2, and SO4•- in the removal of ACA. The ACA degradation pathways were revealed based on the results of high resolution mass spectrometry analysis and calculation of the Fukui index. The presence of anions, such as NO3-, Cl-, and HCO3-, as well as humic acids, induced nonsignificant influence on the ACA degradation, indicating the robustness of the current system for applications in authentic scenarios. Overall results indicated the EC/PMS/Fe(III)-EDDS system is a promising strategy for the practical treatment of NAs in oil and gas field wastewater.

11.
Phys Rev Lett ; 128(17): 176602, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35570449

RESUMEN

Topological materials with broken inversion symmetry can give rise to nonreciprocal responses, such as the current rectification controlled by magnetic fields via magnetochiral anisotropy. Bulk nonreciprocal responses usually stem from relativistic corrections and are always very small. Here we report our discovery that ZrTe_{5} crystals in proximity to a topological quantum phase transition present gigantic magnetochiral anisotropy, which is the largest ever observed to date. We argue that a very low carrier density, inhomogeneities, and a torus-shaped Fermi surface induced by breaking of inversion symmetry in a Dirac material are central to explain this extraordinary property.

12.
Ecol Appl ; : e2756, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36196517

RESUMEN

Functional traits are frequently proposed to determine the invasiveness of alien species. However, few empirical studies have directly manipulated functional traits and tested their importance in the invasion success of alien species into native plant communities, particularly under global change. We manipulated clonal integration (a key clonal functional trait) of four alien clonal plants by severing inter-ramet connections or keeping them intact and simulated their invasion into native plant communities with two levels of species diversity, population density and nutrient availability. High community diversity and density impeded the invasion success of the alien clonal plants. Clonal integration of the alien plants promoted their invasion success, particularly in the low-density communities associated with low species diversity or nutrient addition, which resulted in a negative correlation between the performance of alien plants and native communities, as expected under global change. Thus, clonal integration can favor the invasion success of alien clonal plants into degraded resident communities with a high degree of disturbance and eutrophication. Our findings confirm the role of clonal functional traits in facilitating alien plant invasions into native plant communities and suggest that clonal functional traits should be considered to efficiently restore degraded communities heavily invaded by alien clonal plants.

13.
Cardiovasc Drugs Ther ; 36(6): 1075-1089, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34436706

RESUMEN

PURPOSE: Anti-inflammatory therapy is important for reducing myocardial injury after acute myocardial infarction (MI). New anti-inflammatory drugs and their mechanism are necessary to be explored to improve clinical efficacy. We aimed to improve the efficacy of colchicine on attenuating MI injury by nano-drug delivery systems and to investigate the mechanism of anti-inflammatory. METHODS: A colchicine-containing delivery system based on calcium carbonate nanoparticles (ColCaNPs) was synthesized. The protection against MI by ColCaNPs was evaluated using an in vivo rat model established by ligating the left anterior descending coronary artery. Macrophage polarization and the levels of inflammatory cytokines were determined using immunohistochemistry, Western blot, and ELISA analysis. RESULTS: ColCaNP treatment showed about a 45% reduction in myocardial infarct size and attenuating myocardial fibrosis compared with groups without drug intervention after MI. Furthermore, ColCaNPs significantly decreased the levels of CRP, TNF-α, and IL-1ß in serum and the expression of proinflammatory cytokine in myocardial tissues after MI (p < 0.05). We also found that ColCaNPs notably restrained pyroptosis and inhibited inflammatory response by modulating on M1/M2 macrophage polarization and suppressing TLR4/NFκB/NLRP3 signal pathway. CONCLUSION: Colchicine-containing nanoparticles can protect against MI injury in a clinically relevant rat model by reducing inflammation. In addition, calcium carbonate nanoparticles can increase the cardioprotective effects of colchicine.


Asunto(s)
Infarto del Miocardio , Nanopartículas , Ratas , Animales , Colchicina/farmacología , Colchicina/uso terapéutico , Modelos Animales de Enfermedad , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/prevención & control , Infarto del Miocardio/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/prevención & control , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Citocinas , Nanopartículas/uso terapéutico , Carbonato de Calcio/uso terapéutico
14.
Biochem J ; 478(4): 839-854, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33528492

RESUMEN

Aberrant differentiation of keratinocytes disrupts the skin barrier and causes a series of skin diseases. However, the molecular basis of keratinocyte differentiation is still poorly understood. In the present study, we examined the expression of C7ORF41 using tissue microarrays by immunohistochemistry and found that C7ORF41 is specifically expressed in the basal layers of skin epithelium and its expression is gradually decreased during keratinocytes differentiation. Importantly, we corroborated the pivotal role of C7ORF41 during keratinocyte differentiation by C7ORF41 knockdown or overexpression in TPA-induced Hacat keratinocytes. Mechanismly, we first demonstrated that C7ORF41 inhibited keratinocyte differentiation mainly through formatting a complex with IKKα in the cytoplasm, which thus blocked the nuclear translocation of IKKα. Furthermore, we also demonstrated that inhibiting the PKCα/ERK signaling pathway reversed the reduction in C7ORF41 in TPA-induced keratinocytes, indicating that C7ORF41 expression could be regulated by upstream PKCα/ERK signaling pathway during keratinocyte differentiation. Collectively, our study uncovers a novel regulatory network PKCα/ERK/C7ORF41/IKKα during keratinocyte differentiation, which provides potential therapeutic targets for skin diseases.


Asunto(s)
Epidermis/metabolismo , Quinasa I-kappa B/metabolismo , Queratinocitos/citología , Transducción de Señal/fisiología , Transporte Activo de Núcleo Celular , Diferenciación Celular , Línea Celular Transformada , Regulación hacia Abajo , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Queratinocitos/metabolismo , Proteína Quinasa C-alfa/fisiología , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología
15.
Environ Toxicol ; 37(11): 2780-2792, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36214338

RESUMEN

Oxidative stress is an important factor that causes pancreatic ß-cell dysfunction leading to the development and aggravation of diabetes. Swietenine (Stn) and swietenolide (Std) were isolated from the fruits of Swietenia macrophylla King and had the potential effects on treatment and prevention of diabetes. The aim of this study is to investigate the effects of Stn and Std on insulin secretion and apoptosis in H2 O2 induced insulinoma cell line (INS-1) cells. In the present study, INS-1 cells were treated with 300 µM H2 O2 for 4 h to establish the oxidative damage model. Cell apoptosis, insulin secretion, reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH) levels, and Caspase-3 enzyme activity were measured via corresponding methods. Finally, pancreatic duodenal home box factor-1 (PDX-1), B cell lymphoma-2 (Bcl-2), and Bax protein expression were detected by western blot. Experimental results showed that Stn and Std could significantly improve the INS-1 cell viability, increase the secretion of insulin and reduce the ROS level in H2 O2 induced INS-1 cells. Furthermore, the SOD and GSH levels increased, and the MDA levels decreased compared with the model group after Stn and Std treatment. In addition, after treated with Stn and Std, cell apoptosis was improved, and the activity of Caspase 3 was also significantly inhibited. Meanwhile, Western blot results showed that Stn and Std could up-regulate the expression of PDX-1 protein, and affect the cell apoptosis pathway by up-regulating the expression of Bcl-2 protein and down-regulating the expression of Bax protein. In conclusion, Stn and Std can signifcantly improve the insulin secretion function, protect oxidative stress injury, and reduce apoptosis in H2 O2 induced INS-1 cells, which provides a research basis for Stn and Std to be new drug candidates for the treatment and prevention of diabetes.


Asunto(s)
Diabetes Mellitus , Meliaceae , Enfermedades de Transmisión Sexual , Apoptosis , Caspasa 3/metabolismo , Glutatión/metabolismo , Insulina/metabolismo , Secreción de Insulina , Limoninas , Malondialdehído/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo , Proteína X Asociada a bcl-2/metabolismo
16.
Knee Surg Sports Traumatol Arthrosc ; 30(11): 3760-3766, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35579682

RESUMEN

PURPOSE: The aim of this study was to evaluate the correlation between tibial tuberosity-trochlear groove distance (TT-TG) and body height or knee size, and to find height-related pathologic thresholds of increased TT-TG. METHODS: One-hundred and fifty-three patients with recurrent patellar instability and 151 controls were included. The TT-TG was measured on axial computed tomography (CT) images. Femora width and tibial width were selected to represent knee size. The correlation of TT-TG and gender, body height, femora width, and tibial width was evaluated. The height-related pathologic threshold of increased TT-TG was produced according to Dejour's method. To combine TT-TG with body height and knee size, three new indexes were introduced, ratio of TT-TG to body height (RTH), ratio of TT-TG to femoral width (RTF), and ratio of TT-TG to tibial width (RTT). The ability to predict patellar instability was assessed by the receiver-operating characteristic (ROC) curve, odds ratios (ORs), sensitivity, and specificity. RESULTS: In patients with patellar instability, TT-TG showed significantly correlation with patient height, femoral width, and tibial width respectively (range r = 0.266-0.283). This correlation was not found in the control group. The pathologic threshold of TT-TG was 18 mm in patients < 169 cm (53%), and the mean TT-TG was 21 mm in patients ≥ 169 cm (54%). There was significant difference in RTH, RTF, and RTT between the two groups. RTH, RTF and RTT have similar large area under the curve (AUC) with TT-TG. CONCLUSIONS: TT-TG showed significant correlation with body height and knee size, respectively. The pathologic threshold of increased TT-TG was suggested to be 21 mm for patients [Formula: see text] 169 cm and 18 mm for patients [Formula: see text] 169 cm. Body height-related pathologic threshold provided a supplement for indications of tibial tuberosity medialization. LEVEL OF EVIDENCE: IV.


Asunto(s)
Inestabilidad de la Articulación , Luxación de la Rótula , Articulación Patelofemoral , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/patología , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Luxación de la Rótula/patología , Articulación Patelofemoral/patología , Tibia/diagnóstico por imagen , Tibia/patología
17.
J Wound Care ; 31(Sup3): S29-S38, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35199561

RESUMEN

OBJECTIVE: The purpose of this study was to explore the paracrine effects of adipose-derived stem cells (ASCs) on cutaneous wound healing in diabetic rats. METHOD: The ASCs were isolated and identified by immunofluorescent staining. The ASCs-conditioned medium (ASCs-CM) was harvested. Cell counting kit (CCK)-8 assay, scratch experiments, western blot and quantitative polymerase chain reaction (qPCR) were performed to observe the effects of ASCs-CM on fibroblasts. A full-thickness skin wound diabetic rat model was prepared, using 34 male, Sprague Dawley rats. ASCs-CM or negative-control medium (N-CM) was injected around the wound surface. The existing wound area was measured on days 4, 8, 12 and 16 after the postoperative day, and the wound tissues were collected for immunohistochemical staining and qPCR quantitative study. RESULTS: In this experiment, the isolated cells were characterised as ASCs. The results of CCK-8 assay, cell scratch test, western blot and qPCR showed ASCs-CM could significantly promote the proliferation, migration and differentiation of fibroblasts. Simultaneously, the healing rate of full-thickness skin wounds in diabetic rats was significantly higher in the ASCs-CM group than the N-CM group on days 4, 8, 12 and 16. Immunohistochemical staining and qPCR results showed that the expression of vascular endothelial growth factor (VEGF, days 4 and 8), α-smooth muscle actin (SMA) (days 4 and 16), transforming growth factor (TGF)-ß1 (days 4, 8 and 12) were higher in the ASCs-CM group than that of the N-CM group (p<0.05). CONCLUSION: This experiment demonstrated that ASCs-CM may accelerate wound healing in diabetic rats by promoting the secretion of TGF-ß1, VEGF and the proliferation, migration and differentiation of fibroblasts.


Asunto(s)
Diabetes Mellitus Experimental , Tejido Adiposo , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Células Madre , Estreptozocina , Factor A de Crecimiento Endotelial Vascular , Cicatrización de Heridas
18.
Plant Biotechnol J ; 19(1): 35-50, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32569428

RESUMEN

High-throughput phenotyping is increasingly becoming an important tool for rapid advancement of genetic gain in breeding programmes. Manual phenotyping of vascular bundles is tedious and time-consuming, which lags behind the rapid development of functional genomics in maize. More robust and automated techniques of phenotyping vascular bundles traits at high-throughput are urgently needed for large crop populations. In this study, we developed a standard process for stem micro-CT data acquisition and an automatic CT image process pipeline to obtain vascular bundle traits of stems including geometry-related, morphology-related and distribution-related traits. Next, we analysed the phenotypic variation of stem vascular bundles between natural population subgroup (480 inbred lines) based on 48 comprehensively phenotypic information. Also, the first database for stem micro-phenotypes, MaizeSPD, was established, storing 554 pieces of basic information of maize inbred lines, 523 pieces of experimental information, 1008 pieces of CT scanning images and processed images, and 24 192 pieces of phenotypic data. Combined with genome-wide association studies (GWASs), a total of 1562 significant single nucleotide polymorphism (SNPs) were identified for 30 stem micro-phenotypic traits, and 84 unique genes of 20 traits such as VBNum, VBAvArea and PZVBDensity were detected. Candidate genes identified by GWAS mainly encode enzymes involved in cell wall metabolism, transcription factors, protein kinase and protein related to plant signal transduction and stress response. The results presented here will advance our knowledge about phenotypic trait components of stem vascular bundles and provide useful information for understanding the genetic controls of vascular bundle formation and development.


Asunto(s)
Haz Vascular de Plantas , Zea mays , Estudios de Asociación Genética , Fenotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple , Zea mays/genética
19.
Nanotechnology ; 33(5)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34670212

RESUMEN

Nanotechnology is widely used in targeted drug delivery, but different drug delivery systems need to 're-determine' different synthesis schemes, which greatly limits the further expansion of targeted nanomedicine applications. In this study, we propose a facile and versatile modular stacking strategy to fabricate targeted drug delivery systems to enable tailored designs for patient-specific therapeutic responses. The systems were constructed by a pH-sensitive prodrug module and a mitochondrial targeting module via self-assembly. Using this modular strategy, we successfully prepared two targeting nano-drug delivery systems, TPP-DOX and PK-DOX, where the mitochondrial targeting molecules were triphenylphosphonium (TPP) and 1-(2-Chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide (PK11195), respectively. Confocal laser microscopy and flow cytometry tests revealed that TPP-DOX and PK-DOX exhibited high mitochondria targeting capability and greatly improved the drug retention in drug-resistant cells. The antitumor activity tests showed that the IC50 values of TPP-DOX and PK-DOX in MCF-7/ADR cells were 2.5- and 8.2-fold lower than that of free DOX, respectively. These results indicated that PK was more effective than TPP. The studies on their therapeutic effects on human breast cancer resistant cells verified the feasibility of the modular approach, indicated that the two modular targeted drug delivery systems: (1) retain the drug toxicity and cell-killing effect of the prodrug module, (2) have precise targeting capabilities due to mitochondrial targeting module, (3) enhance drug uptake, reduce drug efflux and reverse the multidrug resistance effect to a certain extent. The results show that modular stacking is a practical, effective and versatile method for preparing targeting drugs with broad application prospects. This study provides an easy approach on preparing customizable targeted drug delivery systems to improve precision therapies.


Asunto(s)
Antineoplásicos , Sistemas de Liberación de Medicamentos/métodos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Nanomedicina/métodos , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Mitocondrias/metabolismo , Neoplasias/metabolismo , Profármacos/química , Profármacos/farmacocinética , Profármacos/farmacología
20.
Biochem J ; 477(3): 691-708, 2020 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-31957809

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is an expanding health problem worldwide. Although many studies have made great efforts to elucidate the pathogenesis of NAFLD, the molecular basis remains poorly understood. Here, we showed that hepatic C7ORF41, a critical regulator of innate immune response, was markedly decreased in diet or genetic-induced NAFLD model. We also demonstrated that C7ORF41 overexpression significantly ameliorated hepatic inflammation and lipid accumulation in palmitic acid (PA)-treated hepatocytes, whereas C7ORF41 knockdown showed the opposite effects. Mechanistically, we found the anti-inflammatory role of C7ORF41 was attributed to the suppression of NF-κB p65-mediated induction of inflammatory cytokines. Moreover, we demonstrated that the suppression of C7ORF41 expression in hepatocytes is due to JNK activation, which promotes c-Jun-mediated transcriptional repression of C7ORF41. In conclusion, our findings suggested that a c-Jun/C7ORF41/NF-κB regulatory network controls the inflammatory response and lipid accumulation in NAFLD and may benefit the development of novel and promising therapeutic targets for NAFLD.


Asunto(s)
Inflamación/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Hepatocitos/patología , Inmunidad Innata , Metabolismo de los Lípidos , Hígado/patología , Ratones , FN-kappa B/metabolismo , Transducción de Señal
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