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1.
Stem Cell Res Ther ; 15(1): 156, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38816830

RESUMO

Mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into cells of different lineages to form mesenchymal tissues, which are promising in regard to treatment for bone diseases. Their osteogenic differentiation is under the tight regulation of intrinsic and extrinsic factors. Transforming growth factor ß (TGF-ß) is an essential growth factor in bone metabolism, which regulates the differentiation of MSCs. However, published studies differ in their views on whether TGF-ß signaling regulates the osteogenic differentiation of MSCs positively or negatively. The controversial results have not been summarized systematically and the related explanations are required. Therefore, we reviewed the basics of TGF-ß signaling and summarized how each of three isoforms regulates osteogenic differentiation. Three isoforms of TGF-ß (TGF-ß1/ß2/ß3) play distinct roles in regulating osteogenic differentiation of MSCs. Additionally, other possible sources of conflicts are summarized here. Further understanding of TGF-ß signaling regulation in MSCs may lead to new applications to promote bone regeneration and improve therapies for bone diseases.


Assuntos
Osso e Ossos , Diferenciação Celular , Células-Tronco Mesenquimais , Osteogênese , Transdução de Sinais , Fator de Crescimento Transformador beta , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Humanos , Fator de Crescimento Transformador beta/metabolismo , Osso e Ossos/metabolismo , Osso e Ossos/citologia , Animais
2.
Adv Healthc Mater ; 13(6): e2302858, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37947125

RESUMO

Cerium (Ce) is a hot topic in the field of materials research due to its electronic layer structure and the unique antioxidant abilities of its oxide (CeO2 ). Cerium oxide nanoparticles (CeO2 NPs) demonstrate their potential as an antioxidant and antibacterial agent. Current research focuses on whether they can be used to promote wound healing and in what manner. This article provides a systematic review of the various forms of CeO2 NPs that are used in wound-healing materials over the past decade, as well as the effectiveness demonstrated by in vivo and in vitro experiments, with a focus on the relationship between concentration and effectiveness. CeO2 NPs are expected to become effective ingredients in dressings that require antibacterial, antioxidant, and wound healing promoting properties. This article serves as a reference for further research and clinical applications of nano-sized CeO2 in wound healing.


Assuntos
Bandagens , Cério , Nanopartículas , Cicatrização , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cério/farmacologia
3.
Environ Res ; 231(Pt 2): 116194, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37217131

RESUMO

Fertilization and rhizosphere selection are key regulators for soil nitrogen (N) cycling and microbiome. Thus, clarifying how the overall N cycling processes and soil microbiome respond to these factors is a prerequisite for understanding the consequences of high inputs of fertilizers, enhancing crop yields, and formulating reasonable nitrogen management strategies under agricultural intensification scenarios. To do this, we applied shotgun metagenomics sequencing to reconstruct N cycling pathways on the basis of abundance and distribution of related gene families, as well as explored the microbial diversity and interaction via high throughput sequencing based on a two-decade fertilization experiment in Loess Plateau of China semiarid area. We found that bacteria and fungi respond divergent to fertilization regimes and rhizosphere selection, in terms of community diversity, niche breadth, and microbial co-occurrence networks. Moreover, organic fertilization decreased the complexity of bacterial networks but increased the complexity and stability of fungal networks. Most importantly, rhizosphere selection exerted more strongly influences on the soil overall nitrogen cycling than the application of fertilizers, accompanied by the increase in the abundance of nifH, NIT-6, and narI genes and the decrease in the abundance of amoC, norC, and gdhA genes in the rhizosphere soil. Furthermore, keystone families screening from soil microbiome (e.g., Sphingomonadaceae, Sporichthyaceae, and Mortierellaceae), which were affected by the edaphic variables, contributed greatly to crop yield. Collectively, our findings emphasize the pivotal roles of rhizosphere selection interacting with fertilization regimes in sustaining soil nitrogen cycling processes in response to decades-long fertilization, as well as the potential importance of keystone taxa in maintaining crop yield. These findings significantly facilitate our understanding of nitrogen cycling in diverse agricultural soils and lay a foundation for manipulating specific microorganisms to regulate N cycling and promote agroecosystem sustainability.


Assuntos
Nitrogênio , Solo , Nitrogênio/análise , Fertilizantes/análise , Microbiologia do Solo , Agricultura , Bactérias/metabolismo
4.
Mater Today Bio ; 19: 100595, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36910271

RESUMO

The biological functions of rare-earth elements (REEs) have become a focus of intense research. Recent studies have demonstrated that ion doping or alloying of some REEs can optimize the properties of traditional biomaterials. Europium (Eu), which is an REE with low toxicity and good biocompatibility, has promising applications in biomedicine. This article systematically reviews the osteogenic, angiogenic, neuritogenic, antibacterial, and anti-tumor properties of Eu-containing biomaterials, thereby paving the way for biomedical applications of Eu. Data collection for this review was completed in October 2022, and 30 relevant articles were finally included. Most articles indicated that doping of Eu ions or Eu-compound nanoparticles in biomaterials can improve their osteogenic, angiogenic, neuritogenic, antibacterial, and anti-tumor properties. The angiogenic, antibacterial, and potential neuritogenic effects of Eu(OH)3 nanoparticles have also been demonstrated.

5.
Sci Total Environ ; 871: 162063, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36746286

RESUMO

Deciphering the ecological role of soil communities in the maintenance of multiple ecosystem functions is pivotal for the conservation and sustainability of soil biodiversity. However, few studies have investigated niche differentiation of abundant and rare microbiota, as well as their contributions to multiple soil elemental cycles, particularly in agroecosystems that have received decades of intense fertilization. Here, we characterized the environmental thresholds and phylogenetic signals for the environmental adaptation of both abundant and rare microbial subcommunities via amplicon sequencing and metagenomic sequencing and explored their importance in sustaining soil multiple nutrient cycling in agricultural fields that were fertilized for two decades. The results showed that rare taxa exhibited narrower niche breadths and weaker phylogenetic signals than abundant species. The assembly of abundant subcommunity was shaped predominantly by dispersal limitation (explained 71.1 % of the variation in bacteria) and undominated processes (explained 75 % of the variation in fungi), whereas the assembly of rare subcommunity was dominated by homogeneous selection process (explained 100 % of the variation in bacteria and 60 % of the variation in fungi). Soil ammonia nitrogen was the leading factor mediating the balance between stochastic and deterministic processes in both abundant (R2 = 0.15, P < 0.001) and rare (R2 = 0.08, P < 0.001) bacterial communities. Notably, the rare biosphere largely contributed to key soil processes such as carbon (R2bacteria = 0.03, P < 0.05; R2fungi = 0.05, P < 0.05) and nitrogen (R2bacteria = 0.03, P < 0.05; R2fungi = 0.17, P < 0.001) cycling. Collectively, these findings facilitate our understanding of the maintenance of rhizosphere bacterial and fungal diversity in response to agricultural fertilization and highlight the key role of rare taxa in sustaining agricultural ecosystem functions.


Assuntos
Microbiota , Solo , Filogenia , Microbiologia do Solo , Bactérias/genética , Nitrogênio
6.
J Transl Med ; 21(1): 8, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36617569

RESUMO

BACKGROUND: Astronauts undergo significant microgravity-induced bone loss during space missions, which has become one of the three major medical problems hindering human's long-term space flight. A risk-free and antiresorptive drug is urgently needed to prevent bone loss during space missions. D-mannose is a natural C-2 epimer of D-glucose and is abundant in cranberries. This study aimed to investigate the protective effects and potential mechanisms of D-mannose against bone loss under weightlessness. METHODS: The hind legs of tail-suspended (TS) rats were used to mimic weightlessness on Earth. Rats were administered D-mannose intragastrically. The osteoclastogenic and osteogenic capacity of D-mannose in vitro and in vivo was analyzed by micro-computed tomography, biomechanical assessment, bone histology, serum markers of bone metabolism, cell proliferation assay, quantitative polymerase chain reaction, and western blotting. RNA-seq transcriptomic analysis was performed to detect the underlying mechanisms of D-mannose in bone protection. RESULTS: The TS rats showed lower bone mineral density (BMD) and poorer bone morphological indices. D-mannose could improve BMD in TS rats. D-mannose inhibited osteoclast proliferation and fusion in vitro, without apparent effects on osteoblasts. RNA-seq transcriptomic analysis showed that D-mannose administration significantly inhibited the cell fusion molecule dendritic cell-specific transmembrane protein (DC-STAMP) and two indispensable transcription factors for osteoclast fusion (c-Fos and nuclear factor of activated T cells 1 [NFATc1]). Finally, TS rats tended to experience dysuria-related urinary tract infections (UTIs), which were suppressed by treatment with D-mannose. CONCLUSION: D-mannose protected against bone loss and UTIs in rats under weightlessness. The bone protective effects of D-mannose were mediated by inhibiting osteoclast cell fusion. Our findings provide a potential strategy to protect against bone loss and UTIs during space missions.


Assuntos
Doenças Ósseas Metabólicas , Reabsorção Óssea , Ausência de Peso , Ratos , Humanos , Animais , Ausência de Peso/efeitos adversos , Manose/farmacologia , Manose/metabolismo , Microtomografia por Raio-X , Osteoclastos , Densidade Óssea , Reabsorção Óssea/prevenção & controle , Reabsorção Óssea/metabolismo
7.
PLoS One ; 7(9): e45215, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23028855

RESUMO

High yield is the most important goal in crop breeding, and boron (B) is an essential micronutrient for plants. However, B deficiency, leading to yield decreases, is an agricultural problem worldwide. Brassica napus is one of the most sensitive crops to B deficiency, and considerable genotypic variation exists among different cultivars in response to B deficiency. To dissect the genetic basis of tolerance to B deficiency in B. napus, we carried out QTL analysis for seed yield and yield-related traits under low and normal B conditions using the double haploid population (TNDH) by two-year and the BQDH population by three-year field trials. In total, 80 putative QTLs and 42 epistatic interactions for seed yield, plant height, branch number, pod number, seed number, seed weight and B efficiency coefficient (BEC) were identified under low and normal B conditions, singly explaining 4.15-23.16% and 0.53-14.38% of the phenotypic variation. An additive effect of putative QTLs was a more important controlling factor than the additive-additive effect of epistatic interactions. Four QTL-by-environment interactions and 7 interactions between epistatic interactions and the environment contributed to 1.27-4.95% and 1.17-3.68% of the phenotypic variation, respectively. The chromosome region on A2 of SYLB-A2 for seed yield under low B condition and BEC-A2 for BEC in the two populations was equivalent to the region of a reported major QTL, BE1. The B. napus homologous genes of Bra020592 and Bra020595 mapped to the A2 region and were speculated to be candidate genes for B efficiency. These findings reveal the complex genetic basis of B efficiency in B. napus. They provide a basis for the fine mapping and cloning of the B efficiency genes and for breeding B-efficient cultivars by marker-assisted selection (MAS).


Assuntos
Boro/deficiência , Brassica napus/genética , Locos de Características Quantitativas , Sementes/genética , Alelos , Cruzamento , Mapeamento Cromossômico , Meio Ambiente , Epistasia Genética , Variação Genética , Genótipo , Haploidia , Fenótipo
8.
Genomics ; 100(4): 222-30, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22800764

RESUMO

The movement of transposable elements (TE) in eukaryotic genomes can often result in the occurrence of nested TEs (the insertion of TEs into pre-existing TEs). We performed a general TE assessment using available databases to detect nested TEs and analyze their characteristics and putative functions in eukaryote genomes. A total of 802 TEs were found to be inserted into 690 host TEs from a total number of 11,329 TEs. We reveal that repetitive sequences are associated with an increased occurrence of nested TEs and sequence biased of TE insertion. A high proportion of the genes which were associated with nested TEs are predicted to localize to organelles and participate in nucleic acid and protein binding. Many of these function in metabolic processes, and encode important enzymes for transposition and integration. Therefore, nested TEs in eukaryotic genomes may negatively influence genome expansion, and enrich the diversity of gene expression or regulation.


Assuntos
Elementos de DNA Transponíveis/genética , Eucariotos/genética , Genoma , Elementos Nucleotídeos Longos e Dispersos/genética , Elementos Nucleotídeos Curtos e Dispersos/genética , Animais , Evolução Molecular , Regulação da Expressão Gênica , Repetições de Microssatélites/genética , Anotação de Sequência Molecular , Software
9.
Zhongguo Zhong Yao Za Zhi ; 34(5): 605-10, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19526794

RESUMO

OBJECTIVE: To investigate the effects of Hydroxy Safflor yellow A (HSYA) on the growth of blood vessel of transplantation tumor of gastric adenocarcinoma cell line BGC-823 in nude mice and its underlying mechanism of antagonizing tumor angiogenesis. METHOD: The BGC-823 cells was subcutaneouly injected into the right anterior armpit of BALB/C nu/nu nude mice and established the animal model of transplantation tumor. Then nude mice were divided into 4 groups at random: model group, control group, high or low dosage of HSYA group. The model group were treated with normal sodium by intraperitoneal injection, HSYA groups were treated with HSYA at concentration of 0.056 g x L(-1) and 0.028 g x L(-1) by intraperitoneal injection, and in these groups each mouse was injected 2 times everyday with 0.2 mL by 4-6 hours interval. The control group were injected in enterocoelia 1 times every 2 days starting from the third day with cytoxan at 2 g x L(-1). 20 days later, the volume and weight of nude mice were observed. The pathological change of tumor tissue was observed under optical microscope. The mRNA expression of VEGF and bFGF of transplantation tumor were detected by real time quantitative PCR. RESULT: The volume (607.42 +/- 252.96) mm3, weight (0.88 +/- 0.14) g of transplantation tumor, the mRNA expression level of VEGF 0.49 +/- 0.13 and bFGF 0.60 +/- 0.48 are reduced significantly after treatment with HSYA at the concentration of 0.028 g x L(-1) compared with physiologic saline-treated group (P < 0.05 or P < 0.01). The tumor pathological angiogenesis of HSYA group is also less obvious than the normal sodium-treated group. CONCLUSION: HSYA in given concentration can inhibit the growth of BGC-823 transplantation tumor, and decreasing the mRNA expression of VEGF and bFGF, which suggests that inhibiting tumor angiogenesis may be one of the mechanisms of HSYA antagonizing tumor.


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Chalcona/análogos & derivados , Fatores de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinonas/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Animais , Vasos Sanguíneos/efeitos dos fármacos , Linhagem Celular Tumoral , Chalcona/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Distribuição Aleatória , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 33(14): 1743-6, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18841783

RESUMO

OBJECTIVE: To observe the effects of Pingyu capsule on such important regulatory factors as cAMP, PKA and PKC of the signal transduction in rats with chronic stress-induced depression. METHOD: Wistar male rats were randomly divided into control group, model group, paroxetine group, and Pingyu capsule low, middle and high doses groups; rats in all groups but the control group were fed in single cage for 21 days and were given such irritations as lightening stroke on pelma, ice water swimming, pyretic fumigation and tail clipping during this period; lobe cortex and hippocampus of all rats were taken out for detection of the cAMP content by means of radioactive immunization, PKA and PKC content by Elisa, and the PKA and PKC activity by radioactive isotope. RESULT: Content of cAMP in lobe cortex and hippocampus, content and activity of PKA in hippocampus, and content of PKC in lobe cortex of rats in the model group were lower than those in the normal group. Pingyu capsule and paroxetine can increase them. CONCLUSION: The anti-depression effect of Pingyu capsule maybe related to its function of adjusting the signal transduction of cAMP-PKA.


Assuntos
Depressão/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Cápsulas/administração & dosagem , Cápsulas/farmacologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Masculino , Proteína Quinase C/metabolismo , Radioimunoensaio , Ratos , Ratos Wistar
11.
Zhongguo Zhong Yao Za Zhi ; 31(13): 1094-6, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17048612

RESUMO

OBJECTIVE: To observe the effects of H. dulcis on relieving alcohol toxicity by animal experiments. METHOD: Male kunming mice were ovraiectomized and randomly divided into 5 groups: control group, model group, and aqueous extracts of H. dulcis group at 0.5, 0.25, 0.125 g x mL(-1). The acute alcohlism animals induced by gastral administration with "Er Guo Tou" and the alchol concentrations in serum were detected after treated with the extracts within 0.5-3 h by biochemical enzymes. RESULT: The alcohol concentration in blood was up to the maximum in 0.5-1.5 h. However, the alcohol concentrations in blood of aqueous extract from H. dulcis group were decreased in 0.5-3 h. The activity of ADH in the liver in aqueous extract of H. dulcis group was increased in 2-3 h, while it was significantly increased in 1-1.5 h (P <0.05). CONCLUSION: The aqueous extract of H. dulcis could reduce the alchol concentration in blood of animals and inrease the activity of ADH after given alcohol. It means the extract has the effect of relieving alcohol toxicity and preventing drunkenness through restraining the absorption of alcohol in the gastrointestinal tract and promoting the metabolism of alcohol in the liver.


Assuntos
Álcool Desidrogenase/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Etanol/sangue , Fígado/enzimologia , Rhamnaceae , Animais , Medicamentos de Ervas Chinesas/isolamento & purificação , Etanol/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos ICR , Plantas Medicinais/química , Distribuição Aleatória , Rhamnaceae/química , Sementes/química
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