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1.
Appl Environ Microbiol ; 87(12): e0296520, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33837014

RESUMO

Warming strongly stimulates soil nitrous oxide (N2O) emission, contributing to the global warming trend. Submerged paddy soils exhibit huge N2O emission potential; however, the N2O emission pathway and underlying mechanisms for warming are not clearly understood. We conducted an incubation experiment using 15N to investigate the dynamics of N2O emission at controlled temperatures (5, 15, 25, and 35°C) in 125% water-filled pore space. The community structures of nitrifiers and denitrifiers were determined via high-throughput sequencing of functional genes. Our results showed that elevated temperature sharply enhanced soil N2O emission from submerged paddy soil. Denitrification was the main contributor, accounting for more than 90% of total N2O emission at all treatment temperatures. N2O flux was coordinatively regulated by nirK-, nirS-, and nosZ-containing denitrifiers but not ammonia-oxidizing archaea or ammonia-oxidizing bacteria. The nirS-containing denitrifiers were more sensitive to temperature shifts, especially at a lower temperature range (5 to 25°C), and showed a stronger correlation with N2O flux than that of nirK-containing denitrifiers. In contrast, nosZ-containing denitrifiers exhibited substantial variation at higher temperatures (15 to 35°C), thereby playing an important role in N2O consumption. Certain taxa of nirS- and nosZ-containing denitrifiers regulated N2O flux, including nirS-containing denitrifiers affiliated with Rhodanobacter and Cupriavidus as well as nosZ-containing denitrifiers affiliated with Azoarcus and Azospirillum. Together, these findings suggest that elevated temperature can significantly increase N2O emission from denitrification in submerged paddy soils by shifting the overall community structures and enriching some indigenous taxa of nirS- and nosZ-containing denitrifiers. IMPORTANCE The interdependence between global warming and greenhouse gas N2O has always been the hot spot. However, information on factors contributing to N2O and temperature-dependent community structure changes is scarce. This study demonstrated high-temperature-induced N2O emission from submerged paddy soils, mainly via stimulating denitrification. Further, we speculate that key functional denitrifiers drive N2O emission. This study showed that denitrifiers were more sensitive to temperature rise than nitrifiers, and the temperature sensitivity differed among denitrifier communities. N2O-consuming denitrifiers (nosZ-containing denitrifiers) were more sensitive at a higher temperature range than N2O-producing denitrifiers (nirS-containing denitrifiers). This study's findings help predict N2O fluxes under different degrees of warming and develop strategies to mitigate N2O emissions from paddy fields based on microbial community regulation.


Assuntos
Poluentes Atmosféricos/análise , Desnitrificação , Óxido Nitroso/análise , Microbiologia do Solo , Poluentes do Solo/análise , Aquecimento Global , Concentração de Íons de Hidrogênio , Nitrificação , Oryza , Solo/química , Temperatura
2.
Microb Ecol ; 81(2): 425-436, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32901387

RESUMO

Biological nitrogen (N2) fixation as a source of new N input into the soil by free-living diazotrophs is important for achieving sustainable rice agriculture. However, the dominant environmental drivers or factors influencing N2 fixation and the functional significance of the diazotroph community structure in paddy soil across a climatic gradient are not yet well understood. Thus, we characterized the diazotroph community and identified the ecological predictors of N2 fixation potential in four different climate zones (mid-temperate, warm-temperate, subtropical, and tropical paddy soils) in eastern China. Comprehensive nifH gene sequencing, functional activity detection, and correlation analysis with environmental factors were estimated. The potential nitrogenase activity (PNA) was highest in warm-temperate regions, where it was 6.2-, 2.9-, and 2.2-fold greater than in the tropical, subtropical, and mid-temperate regions, respectively; nifH gene abundance was significantly higher in warm-temperate and subtropical zones than in the tropical or mid-temperate zones. Diazotroph diversity was significantly higher in the tropical climate zone and significantly lower in the mid-temperate zone. Non-metric multidimensional scaling and canonical correlation analysis indicated that paddy soil diazotroph populations differed significantly among the four climate zones, mainly owing to differences in climate and soil pH. Structural equation models and automatic linear models revealed that climate and nutrients indirectly affected PNA by affecting soil pH and diazotroph community, respectively, while diazotroph community, C/P, and nifH gene abundance directly affected PNA. And C/P ratio, pH, and the diazotroph community structure were the main predictors of PNA in paddy soils. Collectively, the differences in diazotroph community structure have ecological significance, with important implications for the prediction of soil N2-fixing functions under climate change scenarios.


Assuntos
Clima , Microbiota/fisiologia , Fixação de Nitrogênio/fisiologia , Microbiologia do Solo , Carbono/análise , Concentração de Íons de Hidrogênio , Microbiota/genética , Nitrogênio/análise , Nitrogênio/metabolismo , Nitrogenase/análise , Nitrogenase/metabolismo , Oryza , Oxirredutases/genética , Fosfatos/análise , Solo/química
3.
Cell Biochem Funct ; 37(7): 504-515, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31368195

RESUMO

The treatment of neural deficiency after cerebral infarction is challenging, with limited therapeutic options. The transplantation of mesenchymal stem cells (MSCs) to the ischemic penumbra is a potential therapeutic approach. In the present study, a cerebral infarction model was generated by performing middle cerebral artery occlusion (MCAO) in SD rats. The expression of CXCR4 increased, and the number of MSCs migrating to the peri-infarct area was higher in rats transplanted with preconditioned MSCs than in rats transplanted with untreated MSCs. The rate of apoptosis, as evaluated by TUNEL staining and immunoblotting assays, was reduced in rats receiving preconditioned MSCs. A significant amelioration of neural regeneration and improved neurological function were observed in rats injected with preconditioned MSCs compared with those injected with untreated MSCs. However, the application of an siRNA targeting CXCL12 significantly inhibited the protective role of preconditioned MSCs against apoptosis and promoted the migration of MSCs to the ischemic area, leading to impaired neuronal regeneration and limited recovery of neuronal function. Hypoxic preconditioning of MSCs prior to transplantation suppressed apoptosis and increased their migration abilities, leading to the promotion of neuronal regeneration and improvement in neural function after transplantation. This preconditioning strategy may be considered as a potential approach for the modification of MSCs prior to cell transplantation therapy in patients with cerebral infarction. SIGNIFICANCE OF THE STUDY: We found that hypoxic preconditioning of MSCs improved their ability to promote neuronal regeneration and the recovery of neuronal function. Moreover, we showed that CXCR4 inhibited apoptosis, improved cell homing, and promoted neuronal differentiation, without influencing angiogenesis. Our study provides a relatively safe preconditioning method for potential use for cell transplantation therapy in ischemic cerebral infarction. The results presented here will facilitate the development of novel strategies and techniques to improve the tolerance and migration ability of transplanted cells for the treatment of cerebral infarction sequelae.


Assuntos
Infarto Cerebral/metabolismo , Quimiocina CXCL12/metabolismo , Modelos Animais de Doenças , Hipóxia , Células-Tronco Mesenquimais/metabolismo , Receptores CXCR4/metabolismo , Animais , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular , Infarto Cerebral/terapia , Quimiocina CXCL12/antagonistas & inibidores , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Neurônios , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores CXCR4/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
4.
Biotechnol Lett ; 38(12): 2163-2167, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27627898

RESUMO

OBJECTIVE: Paddy soils contain relatively greater organic matter and water contents than other soils thereby limiting effective mRNA extraction. A modification of the conventional mRNA soil extraction method specific to paddy soils is described. RESULTS: Two main modifications for co-extraction of DNA and RNA are: (1) addition of 20 % (w/v) sodium dodecyl sulphate to 10 % (w/v) hexadecyltrimethylammonium bromide extraction buffer, and (2) fresh soil, initially frozen at -80 °C, is immediately immersed in extraction buffer. The high-quality total RNA extracted can be directly used in downstream analyses without an additional step to remove humic acid. RNA purification was conducted to remove 5S rRNA, and the mRNA was enriched by selectively digesting rRNA. cDNA synthesised by reverse transcriptase was not contaminated by the reagents or genomic DNA. CONCLUSION: The modified method for mRNA extraction from paddy soil is suitable for analysing the expression of microbial genes from fresh paddy soil.


Assuntos
RNA Mensageiro/isolamento & purificação , Solo , Microbiologia do Solo
5.
Front Microbiol ; 15: 1374199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550861

RESUMO

The combined application of chemical and organic fertilizers has been recognized to enhance soil fertility and foster the soil microbial ecosystem. However, the optimal ratio of chemical and organic fertilizers in oilseed rape cultivation is still uncertain, and the role of rhizosphere effect is still unclear. Thus, this study aimed to elucidate the impacts of varying ratios of chemical and organic fertilizers on the structure and potential functionalities of rhizosphere and non-rhizosphere soil microbial communities. The interplay of microbial communities with soil properties and oilseed rape root exudates was investigated in controlled pot cultivations receiving varying ratios of chemical and organic fertilizers. Results indicated clear segregation in the soil bacterial community, influenced by both fertilization treatments and rhizosphere effects. The bacterial community structure significantly correlated with nitrate nitrogen, organic acids, and dissolved organic carbon (DOC) content. Rhizosphere effects led to increased bacteria abundance, reduced diversity, and decreased network stability. Notably, F3 treatment receiving 25% chemical and 75% organic fertilizers showed a significantly higher abundance at 1.43 × 1011 copies g-1 dry soil, accompanied by increased species and genetic diversity, and ecological network complexity. This treatment also yielded the highest aboveground biomass of oilseed rape. However, the application of organic fertilizers also increased the risk of plant pathogenicity. This study reveals the impact of fertilizers and rhizosphere effects on soil microbial community structure and function, shedding light on the establishment of more effective fertilization schemes for oilseed rape agriculture.

6.
Exp Gerontol ; 191: 112448, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38697555

RESUMO

BACKGROUND: Stroke is a debilitating condition with high morbidity, disability, and mortality that significantly affects the quality of life of patients. In China, the WenYang FuYuan recipe is widely used to treat ischemic stroke. However, the underlying mechanism remains unknown, so exploring the potential mechanism of action of this formula is of great practical significance for stroke treatment. OBJECTIVE: This study employed network pharmacology, molecular docking, and in vivo experiments to clarify the active ingredients, potential targets, and molecular mechanisms of the WenYang FuYuan recipe in cerebral ischemia-reperfusion injury, with a view to providing a solid scientific foundation for the subsequent study of this recipe. MATERIALS AND METHODS: Active ingredients of the WenYang FuYuan recipe were screened using the traditional Chinese medicine systems pharmacology database and analysis platform. Network pharmacology approaches were used to explore the potential targets and mechanisms of action of the WenYang FuYuan recipe for the treatment of cerebral ischemia-reperfusion injury. The Middle Cerebral Artery Occlusion/Reperfusion 2 h Sprague Dawley rat model was prepared, and TTC staining and modified neurological severity score were applied to examine the neurological deficits in rats. HE staining and Nissl staining were applied to examine the pathological changes in rats. Immunofluorescence labeling and Elisa assay were applied to examine the expression levels of certain proteins and associated factors, while qRT-PCR and Western blotting were applied to examine the expression levels of linked proteins and mRNAs in disease-related signaling pathways. RESULTS: We identified 62 key active ingredients in the WenYang FuYuan recipe, with 222 highly significant I/R targets, forming 138 pairs of medication components and component-targets, with the top five being Quercetin, Kaempferol, Luteolin, ß-sitosterol, and Stigmasterol. The key targets included TP53, RELA, TNF, STAT1, and MAPK14 (p38MAPK). Targets related to cerebral ischemia-reperfusion injury were enriched in chemical responses, enzyme binding, endomembrane system, while enriched pathways included lipid and atherosclerosis, fluid shear stress and atherosclerosis, AGE-RAGE signaling in diabetic complications. In addition, the main five active ingredients and targets in the WenYang FuYuan recipe showed high binding affinity (e.g. Stigmasterol and MAPK14, total energy <-10.5 Kcal/mol). In animal experiments, the WenYang FuYuan recipe reduced brain tissue damage, increased the number of surviving neurons, and down-regulated S100ß and RAGE protein expression. Moreover, the relative expression levels of key targets such as TP53, RELA and p38MAPK mRNA were significantly down-regulated in the WenYang FuYuan recipe group, and serum IL-6 and TNF-a factor levels were reduced. After WenYang FuYuan recipe treatment, the AGE-RAGE signaling pathway and downstream NF-kB/p38MAPK signaling pathway-related proteins were significantly modulated. CONCLUSION: This study utilized network pharmacology, molecular docking, and animal experiments to identify the potential mechanism of the WenYang FuYuan recipe, which may be associated with the regulation of the AGE-RAGE signaling pathway and the inhibition of target proteins and mRNAs in the downstream NF-kB/p38MAPK pathway.


Assuntos
Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , NF-kappa B , Farmacologia em Rede , Traumatismo por Reperfusão , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Masculino , Ratos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , NF-kappa B/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Sci Rep ; 13(1): 18064, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872188

RESUMO

In this study, a porous structure for a porous liquid storage medium is generated, and the homogenization theory based on displacement boundary conditions is used to predict the effective mechanical properties. The relationship between the porous material's macroscopic mechanical properties and microstructure is next analyzed. In order to establish the relationship between the microstructure of porous materials and their macroscopic mechanical properties, assuming that the pores grow along the z direction, a method is proposed to generate 3D open-cell porous materials based on six design parameters (i.e., the number of pores, porosity, irregularity of pore distribution, the randomness of pore growth in the x and y directions, and randomness of pore size). Since the porosity of oil-bearing materials ranges from 20 to 30%, the porosity of the RVE (Representative Volume Element) was kept under control at about 25%, and the effect of the six design factors on the mechanical properties of the RVE was investigated. Utilizing SLA 3D printing technology, specimens were produced, and compression tests were used to show how useful the results of the numerical analysis were. The results demonstrated that after the number of RVE pores reaches 9, the numerical results have good repeatability. The irregularity of the initial pore distribution has little effect on the effective mechanical properties of the RVE. At the same time, the increase in the randomness of pore growth and the randomness of pore size increases the degree of weakening of the mechanical properties in the z-direction, while reducing the degree of weakening in the x and y directions, but the latter has a smaller impact. Furthermore, there is a superimposition effect of design parameters on the RVE.

8.
Front Microbiol ; 14: 1130298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547687

RESUMO

Water and fertilizer managements are the most common practices to maximize crop yields, and their long-term impact on soil microbial communities has been extensively studied. However, the initial response of microbes to fertilization and soil moisture changes remains unclear. In this study, the immediate effects of nitrogen (N)-fertilizer application and moisture levels on microbial community of paddy soils were investigated through controlled incubation experiments. Amplicon sequencing results revealed that moisture had a stronger influence on the abundance and community composition of total soil bacteria, as well as ammonia oxidizing-archaea (AOA) and -bacteria (AOB). Conversely, fertilizer application noticeably reduced the connectivity and complexity of the total bacteria network, and increasing moisture slightly exacerbated these effects. NH4+-N content emerged as a significant driving force for changes in the structure of the total bacteria and AOB communities, while NO3--N content played more important role in driving shifts in AOA composition. These findings indicate that the initial responses of microbial communities, including abundance and composition, and network differ under water and fertilizer managements. By providing a snapshot of microbial community structure following short-term N-fertilizer and water treatments, this study contributes to a better understanding of how soil microbes respond to long-term agriculture managements.

9.
Comb Chem High Throughput Screen ; 26(6): 1157-1166, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35993467

RESUMO

OBJECTIVE: To explore the clinical efficacy of Zhuang Medicine Lotus Acupuncture Cupping Stasis Therapy on patients with postherpetic neuralgia (PHN) and its action mechanism. METHODS: 36 patients are randomly divided into Lotus Acupuncture Cupping Stasis Therapy group, pure cupping group and gabapentin group, with a total of five observation points for the first, fifth, tenth, fifteenth, and twentieth sessions of therapy (one session every three days). At each observation point, the venous blood of the patients is taken, and the contents of and changes in WNT3a, Frizzled8, ß-catenin, IL-18, TNF-α, NR2B, NK-1 and SP are tested by ELISA, RT-PCR and WesternBlot, respectively. The VAS scores and safety of the patients in the three groups are compared. RESULTS: With increased time spent in therapy, the VAS scores of patients in each group decreased gradually and there was a significant reduction in pain in patients in the Lotus Acupuncture Cupping Stasis Therapy group compared to the gabapentin and pure cupping groups (P<0.05). The levels of IL-18, TNF-α, NK-1, SP, WNT3a, Frizzled 8 and ß-catenin in the serum of all patients experienced a constant decline over time (P<0.05); the levels of the aforesaid factors in the serum of patients in the Lotus Acupuncture Cupping Stasis Therapy group dropped remarkably after the tenth session of therapy compared to those in gabapentin and pure cupping groups (P<0.05). CONCLUSIONS: Zhuang Medicine Lotus Acupuncture Cupping Stasis Therapy can significantly reduce the pain of PHN patients, with a good therapeutic effect, and it is worthy of clinical use.


Assuntos
Terapia por Acupuntura , Lotus , Neuralgia Pós-Herpética , Humanos , Neuralgia Pós-Herpética/terapia , Interleucina-18 , beta Catenina , Gabapentina , Fator de Necrose Tumoral alfa , Resultado do Tratamento
10.
Appl Microbiol Biotechnol ; 95(4): 1061-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22159889

RESUMO

Carbon dioxide (CO(2)) assimilation by autotrophic bacteria is an important process in the soil carbon cycle with major environmental implications. The long-term impact of fertilizer on CO(2) assimilation in the bacterial community of paddy soils remains poorly understood. To narrow this knowledge gap, the composition and abundance of CO(2)-assimilating bacteria were investigated using terminal restriction fragment length polymorphism and quantitative PCR of the cbbL gene [that encodes ribulose-1,5-biphosphate carboxylase/oxygenase (RubisCO)] in paddy soils. Soils from three stations in subtropical China were used. Each station is part of a long-term fertilization experiment with three treatments: no fertilizer (CK), chemical fertilizers (NPK), and NPK combined with rice straw (NPKM). At all of the stations, the cbbL-containing bacterial communities were dominated by facultative autotrophic bacteria such as Rhodopseudomonas palustris, Bradyrhizobium japonicum, and Ralstonia eutropha. The community composition in the fertilized soil (NPK and NPKM) was distinct from that in unfertilized soil (CK). The bacterial cbbL abundance (3-8 × 10(8) copies g soil(-1)) and RubisCO activity (0.40-1.76 nmol CO(2) g soil(-1) min(-1)) in paddy soils were significantly positively correlated, and both increased with the addition of fertilizer. Among the measured soil parameters, soil organic carbon and pH were the most significant factors influencing the community composition, abundance, and activity of the cbbL-containing bacteria. These results suggest that long-term fertilization has a strong impact on the activity and community of cbbL-containing bacterial populations in paddy soils, especially when straw is combined with chemical fertilizers.


Assuntos
Bactérias/metabolismo , Fertilizantes , Ribulose-Bifosfato Carboxilase/metabolismo , Microbiologia do Solo , Bactérias/classificação , Bactérias/enzimologia , Bactérias/genética , Clonagem Molecular , Genes Bacterianos , Concentração de Íons de Hidrogênio , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
11.
J Sci Food Agric ; 92(5): 1064-72, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-21796637

RESUMO

BACKGROUND: Denitrification is a microbial process that has received considerable attention during the past decade since it can result in losses of added nitrogen fertilisers from agricultural soils. Paddy soil has been known to have strong denitrifying activity, but the denitrifying microorganisms responsible for fertilisers in paddy soil are not well known. The objective of this study was to explore the impacts of 17-year application of inorganic and organic fertiliser (rice straw) on the abundance and composition of a nosZ-denitrifier community in paddy soil. Soil samples were collected from CK plots (no fertiliser), N (nitrogen fertiliser), NPK (nitrogen, phosphorus and potassium fertilisers) and NPK + OM (NPK plus organic matter). The nitrous oxide reductase gene (nosZ) community composition was analysed using terminal restriction fragment length polymorphism, and the abundance was determined by quantitative PCR. RESULTS: Both the largest abundance of nosZ-denitrifier and the highest potential denitrifying activity (PDA) occurred in the NPK + OM treatment with about four times higher than that in the CK and two times higher than that in the N and NPK treatments (no significant difference). Denitrifying community composition differed significantly among fertilisation treatments except for the comparison between CK and N treatments. Of the measured abiotic factors, total organic carbon was significantly correlated with the observed differences in community composition and abundance (P < 0.01 by Monte Carlo permutation). CONCLUSION: This study shows that the addition of different fertilisers affects the size and composition of the nosZ-denitrifier community in paddy soil.


Assuntos
Bactérias/genética , Desnitrificação , Fertilizantes , Nitrogênio/metabolismo , Oryza/metabolismo , Oxirredutases/genética , Microbiologia do Solo , Agricultura , Bactérias/metabolismo , Carbono/análise , Desnitrificação/genética , Genes Bacterianos , Método de Monte Carlo , Oryza/microbiologia , Polimorfismo de Fragmento de Restrição , Solo/química
12.
J Tissue Eng Regen Med ; 16(4): 409-421, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156316

RESUMO

Bioceramic scaffolds for repairing mandibular bone defects have considerable effects, whereas pore architecture in porous scaffolds on osteogenesis in specific structures is still controversial. Herein 6 mol% magnesium-substituted calcium silicate scaffolds were fabricated with similar porosity (∼58%) but different cylindrical pore dimensions (Ø 480, 600, and 720 µm) via digital light processing-based three-dimensional (3D) printing technique. The mechanical properties, bioactive ion release, and bio-dissolution of the bioceramic scaffolds were evaluated in vitro, and the facilitation of scaffolds on bone formation was investigated after implanting in vivo. The results showed that as the pore dimension increased, the scaffolds indicated similar surface microstructures, but their compressive strength was enhanced gradually. There was no significant difference in vitro bio-dissolution between the 480 and 600 µm groups, whereas the 720 µm group showed a much slower dissolution and ion release. Interestingly, the two-dimensional/three-dimensional (2D/3D) micro-CT reconstruction analysis of rabbits' mandibular bone defects model showed that the 600 µm group exhibited evidently higher ratio of the newly formed bone volume to total volume (BV/TV) and trabecular number (Tb. N) values and lower ratio of the scaffolds residual volume to total volume (RV/TV) compare to the other two sizes. Furthermore, the histological analysis also revealed a considerably higher new bone ingrowth rate in the 600 µm group than the other two groups at 4-12 weeks post-implantation. Totally, it is proved from these experimental studies that the DLP-based accurately fabricated calcium (Ca) silicate bioceramic scaffolds with appropriate pore dimensions (i.e., 600 µm in pore size) are promising to guide new bone ingrowth and thus accelerate the regeneration and repair of cranial maxillofacial or periodontal bone defects.


Assuntos
Osteogênese , Alicerces Teciduais , Animais , Regeneração Óssea , Porosidade , Impressão Tridimensional , Coelhos , Crânio/patologia , Alicerces Teciduais/química
13.
Materials (Basel) ; 15(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36431677

RESUMO

Cu nanowires and a nanoporous Ag matrix were fabricated through directional solidification and selective dissolution of Ag-Cu eutectic alloys. Ag-39.9at.%Cu eutectic alloys were directionally solidified at growth rates of 14, 25, and 34 µm/s at a temperature gradient of 10 K/cm. The Cu phase in the Ag matrix gradually changed from lamellar to fibrous with an increase in the growth rate. The Ag matrix phase was selectively dissolved, and Cu nanowires of 300-600 nm in diameter and tens of microns in length were prepared in 0.1 M borate buffer with a pH of 9.18 at a constant potential of 0.7 V (vs. SCE). The nanoporous Ag matrix was fabricated through selective dissolution of Cu fiber phase in 0.1 M acetate buffer with a pH of 6.0 at a constant potential of 0.5 V (vs. SCE). The diameter of Ag pores decreased with increasing growth rate. The diameter and depth of Ag pores increased when corrosion time was extended. The depth of the pores was 30 µm after 12 h.

14.
Sci Rep ; 12(1): 13989, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35977965

RESUMO

Rising temperature affects microbial composition and function in agriculture field, especially under nitrogen fertilization. In this study, we investigated the bacterial community of paddy soil incubated at controlled temperatures (5 °C, 15 °C, 25 °C, and 35 °C). Results showed that the response of bacterial communities to temperature was not uniform. Temperature elevation from 15 to 25 °C abruptly shifted the soil bacterial community, whereas elevation from 5 to 15 °C and from 25 to 35 °C had a marginal effect. The bacterial α-diversity was higher at 5 °C and 15 °C, owing to the massively distributed taxa with low abundance. However, as the temperature increased to 25 °C and 35 °C, these taxa were diminished, whereas Firmicutes significantly increased, resulting in a strong decline in α-diversity. Simultaneously, bacterial network complexity significantly increased at 25 °C and 35 °C, indicating the bacteria had closer interactions. Nitrogen application aggravated the variation in bacterial diversity and network complexity among temperatures. Interestingly, most complex network was observed under higher temperatures in fertilized soils. Collectively, these results indicate that nitrogen exacerbates the response of the soil bacterial community to temperature, and association between diversity and network complexity may be present.


Assuntos
Nitrogênio , Microbiologia do Solo , Agricultura/métodos , Bactérias/genética , Nitrogênio/análise , Solo
15.
RSC Adv ; 11(20): 12381-12391, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35423747

RESUMO

A superamphiphobic coating is usually prepared via a reduction reaction and then deposited onto the surface of the substrate. This technology is difficult to control and achieve high bond strength, which easily leads to powder shedding. To overcome this issue, electroplating technology is usually preferred for preparing adhesion coatings. However, the coating prepared using this method is usually suitable only for hard steel substrates, and not for soft substrates such as carbon brushes. Herein, we demonstrate an air spray technology for preparing anti-greasy and conductive superamphiphobic graphite-1H,1H,2H,2H-perfluorooctyltrichlorosilane-SiO2 (GPS) coatings suitable for both soft substrates (carbon brushes) and hard substrates (collector rings). The sheet resistance of the coating with 10% graphite content is 4.8 × 10-3 Ω â–¡-1 for a 10 µm thin coating, corresponding to a resistivity of 4.8 µΩ cm. More importantly, the prepared coating has excellent liquid repellency, such as water, rapeseed oil and n-hexane. In addition, the coating has excellent anti-greasy and mechanical properties, which provide a brand-new solution for the greasy pollution in the engineering field. These advantages will enhance the application of superamphiphobic GPS coating in the fields of hydropower, wind power and transportation, and so on.

16.
Brain Res ; 1752: 147216, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33333054

RESUMO

Cerebral ischemia is the most common cause of hippocampal neuronal death and the most prevalent cause of stroke with high mortality rate. Ferroptosis has been suggested to affect the role of hippocampal neurons. This study explores the influence of lentivirus infection-induced ferritin overexpression in hippocampal neuronal injury and death through simulations in August Copenhagen Irish rat models. Twenty-four-hour cerebral ischemia-reperfusion injury was induced in the rats after 90-min middle cerebral artery occlusion (MCAO). Ferritin overexpression was induced through lentivirus infection. The Morris Water Maze (MWM) test and tau hyperphosphorylation test were performed on hippocampal neurons to establish a MCAO model. The effect of ferritin overexpression on hippocampal neuronal death was evaluated using hematoxylin-eosin staining and annexin V/propidium iodide flow cytometry. The MWM test revealed that MCAO modeling decreased the cognitive and locomotor capacity of the rats, whereas ferritin overexpression partially reversed the effect of MCAO. In addition, the hyperphosphorylation of tau caused by MCAO was reduced by ferritin. Pathogenic changes, impaired viability, increased apoptosis, and elevated caspase-9 cleavage in hippocampal neurons were clearly recovered by ferritin. Moreover, robust reactive oxygen species production and glutathione consumption, which was induced by MCAO modeling, were ameliorated by ferritin. Furthermore, two key modulators of ferroptosis, p53 and SLC7A11, were demonstrated to be upregulated by MCAO modeling and downregulated by ferritin. Ferritin reduction is essential for cerebral ischemia-induced hippocampal neuronal ferroptosis mediated via p53 and SLC7A11.


Assuntos
Isquemia Encefálica/metabolismo , Ferritinas/metabolismo , Ferroptose , Hipocampo/metabolismo , Neurônios/metabolismo , Transdução de Sinais , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Morte Celular , Masculino , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/metabolismo
17.
Sci Total Environ ; 787: 147523, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33992946

RESUMO

High yields and environment-related issues because of over-fertilization in rice (Oryza sativa L.) production is a major concern in China. Partial replacement of mineral fertilizer (MF) with organic matter is considered a win-win approach for resource-saving and environmentally friendly rice production. Here, we examined the effects of reduced MF and in situ crop residue on the rice yield and soil fertility in the long term. A 27-year field experiment (a randomized block design with three replicates) in subtropical China was conducted to test the feasibility of the substitution in a double rice paddy ecosystem. The treatments were CT (no fertilizer application considered as control), NPK (mineral fertilizer N, P, and K), and RFC (reduced MF and in situ crop residue to supplement the reduced NPK dose). The crop residue included half of the rice straw and green manure contents, which were retained in situ in the RFC treatment. The RFC maintained the same rice yield and soil fertility levels as NPK. In general, soil organic carbon (SOC) and total nitrogen (TN) content in RFC increased by 10.3% -20.8%, and 7.5% -28.0%, respectively, than that in NPK from the 5th to the 25th years. There was no significant difference in the content and net accumulation of SOC, TN, and TP and soil available nutrients between the RFC and NPK treatments after 25 years. The average annual yields were 9690 and 9872 kg ha-1 for the NPK and RFC treatments, respectively. There was no difference in the yield of the first, second, and annual rice crops between RFC and NPK in most years (six of the fifty-four seasons showed a significant difference). RFC increased the partial factor productivity (PFP), agronomic efficiency (AE) of MF, and yield stability (CV) (p < 0.05). Positive nutrient balance and a reduced loss of nutrients are evident reasons for achieving better indicators (PFP, AE, and CV) for nutrient compensation and organic nutrient utilization in the RFC treatment. The partial replacement of MF with in situ crop residue retention, is a simple and efficient way to maintain the soil fertility and rice yield as NPK in southern China.

18.
Hum Exp Toxicol ; 40(12_suppl): S347-S358, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34533063

RESUMO

Background: Alzheimer's disease (AD) has affected numerous elderly individuals worldwide. Panax notoginseng has been shown to ameliorate AD symptoms, and notoginsenoside R2 is a key saponin identified in this plant. Purpose: In the current study, we aimed to explore whether notoginsenoside R2 could improve the prognosis of AD. Methods: Herein, primary rat cortical neurons were isolated and they were treated with amyloid beta-peptide (Aß) 25-35 oligomers. Cellular apoptosis was examined via flow cytometry and Western blotting. miR-27a and SOX8 mRNA expression levels were quantified by quantitative reverse transcription-polymerase chain reaction. Furthermore, the interaction between miR-27a and SOX8 was investigated by utilizing a dual-luciferase reporter assay. Finally, an AD mouse model was established to validate the in vitro findings. Results: Notoginsenoside R2 alleviated Aß25-35-triggered neuronal apoptosis and inflammation. During this process, miR-27a expression was decreased by notoginsenoside R2, and miR-27a negatively modulated SOX8 expression. Furthermore, activation of SOX8 upregulated ß-catenin expression, thus suppressing apoptosis and neuroinflammation. Conclusions: Our animal experiments revealed that notoginsenoside R2 enhanced the cognitive function of AD mice and inhibited neuronal apoptosis. Notoginsenoside R2 ameliorated AD symptoms by reducing neuronal apoptosis and inflammation, thus suggesting a novel direction for AD pharmacotherapy.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Apoptose/efeitos dos fármacos , Ginsenosídeos/farmacologia , Inflamação/tratamento farmacológico , MicroRNAs/metabolismo , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
19.
Kaohsiung J Med Sci ; 37(9): 803-811, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34110683

RESUMO

Epilepsy is a clinical syndrome caused by the highly synchronized abnormal discharge of brain neurons. It has the characteristics of paroxysmal, transient, repetitive, and stereotyped. Circular RNAs (circRNAs) are a recently discovered type of noncoding RNA with diverse cellular functions related to their excellent stability; additionally, some circRNAs can bind and regulate microRNAs (miRNAs). The present study was designed to screen the differentially expressed circRNA in an acute seizure model of epilepsy in mice, analyze the related miRNA and mRNA, and study their participating functions and enrichment pathways. In order to obtain the differential expression of circRNA in epilepsy and infer their function, we used next-generation sequencing and found significantly different transcripts. CIRI (circRNA identifier) software was used to predict circRNA from the hippocampus cDNA, EdgeR was applied for the differential circRNA analysis between samples, and Cytoscape 3.7.2 software was used to draw the network diagram. A total of 10,388 differentially expressed circRNAs were identified, of which 34 were upregulated and 66 were downregulated. Among them, mm9_circ_008777 and mm9_circ_004424 were the key upregulated genes, and their expression in the epilepsy group was verified using Quantitative real-time PCR (QPCR). The analysis indicated that the extracted gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were closely related to several epilepsy-associated processes. This study determined that mm9_circ_008777 and mm9_circ_004424 are potential biomarkers of epilepsy, which play important roles in epilepsy-related pathways. These results could help improve the understanding of the biological mechanisms of circRNAs and epilepsy treatments.


Assuntos
Epilepsia/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Hipocampo/patologia , RNA Circular/genética , Animais , Camundongos
20.
ACS Appl Mater Interfaces ; 12(15): 18174-18181, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32202403

RESUMO

Inspired by the gas-trapped mechanism underwater of Argyroneta aquatica, we prepared a superhydrophobic yarn with a fiber network structure via a facile and environmentally friendly method. Attributed to the low surface energy, the superhydrophobic fiber network structure on the yarn is able to trap and transport bubbles directionally underwater. The functional yarn has good superhydrophobic and superaerophilic properties underwater to realize the directional transport of bubbles underwater without being pumped. We designed demonstration experiments on the antibuoyancy directional bubble transportation, which indicated the feasibility in the applications of gas-related fields. Significantly, on further testing, where the superhydrophobic yarn is put into a U-shaped pipe, we obtain a gas-siphon underwater with a high flux. The superhydrophobic fiber structure yarn can trap the gas underwater to enable the self-starting behavior while no manual intervention is used. The gas-siphon can convey gas over the edge of a vessel and deliver it at a higher level without energy input, which is driven by the differential pressure. The relationship between the differential pressure and the volume flux of transport bubbles is investigated. The experimental results show that the prepared superhydrophobic yarn has the advantages of good stability, easy preparation, and low cost in bubble continuous transportation underwater, which provides a novel strategy for the development and application of new technologies such as directional transportation, separation, exhaustion, and collection of gases in water.

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