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1.
Immunology ; 168(1): 49-62, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35908188

RESUMO

Obesity is generally associated with low-grade inflammation. Adipose tissue macrophages (ATMs) orchestrate metabolic inflammation. The classical (M1-like) or alternative (M2-like) activation of ATMs is functionally coupled with the metabolic status of fat tissues. It has been found that T-cell immunoglobulin- and mucin-domain-containing molecule-4 (Tim-4) inhibits inflammation by regulating macrophages. However, the exact role of Tim-4 in macrophage polarization and obesity remains unknown. Here, we identified Tim-4 as a critical switch governing macrophage M1/M2 polarization and energy homeostasis. Tim-4 deletion led to spontaneous obesity in elder mice and promoted obesity severity of db/db mice. Obesity microenvironment enhanced the expression of Tim-4 in white adipose tissue and ATMs. In vitro, we detected an increase in M1-like cells and decrease in M2-like cells in both peritoneal macrophages and bone marrow-derived macrophages from Tim-4 knockout mice. Mechanistically, we demonstrated that Tim-4 promoted M2-like macrophages polarization via suppressing nuclear factor kappa B (NF-κB) signaling pathway. In addition, we found that Tim-4 promoted TLR4 internalization, which might contribute to regulation of NF-κB signaling. Collectively, these results indicated that Tim-4 maintained adipose tissue homeostasis by regulating macrophage polarization via NF-κB pathway, which would provide a new target for obesity intervention.


Assuntos
Tecido Adiposo , Macrófagos , Proteínas de Membrana , Animais , Camundongos , Homeostase , Imunoglobulinas/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Obesidade/metabolismo , Linfócitos T/metabolismo , Transdução de Sinais
2.
Physiol Plant ; 169(2): 244-257, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32020618

RESUMO

The biological functionality of many members of the 14-3-3 gene family is regulated via phosphorylation at multiple amino acid residues. The specific phosphorylation-mediated regulation of these proteins during cassava root tuberization, however, is not well understood. In this study, 15 different 14-3-3 genes (designated MeGRF1 - 15) were identified within the cassava genome. Based upon evolutionary conservation and structural analyses, these cassava 14-3-3 proteins were grouped into ε and non-ε clusters. We found these 15 MeGRF genes to be unevenly distributed across the eight cassava chromosomes. When comparing the expression of these genes during different developmental stages, we found that three of these genes (MeGRF9, 12 and 15) were overexpressed at all developmental stages at 75, 104, 135, 182 and 267 days post-planting relative to the fibrous root stage, whereas two (MeGRF5 and 7) were downregulated during these same points. In addition, the expression of most MeGRF genes changed significantly in the early and middle stages of root tuberization. This suggests that these different MeGRF genes likely play distinct regulatory roles during cassava root tuberization. Subsequently, 18 phosphorylated amino acid residues were detected on nine of these MeGRF proteins. A phosphomimetic mutation at serine-65 in MeGRF3 in Arabidopsis thaliana (Arabidopsis) slightly influenced starch metabolism in these plants, and significantly affected the role of MeGRF3 in salt stress responses. Together these results indicate that 14-3-3 genes play key roles in responses to abiotic stress and the regulation of starch metabolism, offering valuable insights into the functions of these genes in cassava.


Assuntos
Proteínas 14-3-3/genética , Manihot/genética , Família Multigênica , Proteínas de Plantas/genética , Proteínas 14-3-3/química , Metabolismo dos Carboidratos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Fosforilação , Filogenia , Proteínas de Plantas/química , Estresse Fisiológico
3.
Int J Mol Sci ; 20(20)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31614967

RESUMO

Rubber particles are a specific organelle for natural rubber biosynthesis (NRB) and storage. Ethylene can significantly improve rubber latex production by increasing the generation of small rubber particles (SRPs), regulating protein accumulation, and activating many enzyme activities. We conducted a quantitative proteomics study of different SRPs upon ethylene stimulation by differential in-gel electrophoresis (DIGE) and using isobaric tags for relative and absolute quantification (iTRAQ) methods. In DIGE, 79 differentially accumulated proteins (DAPs) were determined as ethylene responsive proteins. Our results show that the abundance of many NRB-related proteins has been sharply induced upon ethylene stimulation. Among them, 23 proteins were identified as rubber elongation factor (REF) and small rubber particle protein (SRPP) family members, including 16 REF and 7 SRPP isoforms. Then, 138 unique phosphorylated peptides, containing 129 phosphorylated amino acids from the 64 REF/SRPP family members, were identified, and most serine and threonine were phosphorylated. Furthermore, we identified 226 DAPs from more than 2000 SRP proteins by iTRAQ. Integrative analysis revealed that almost all NRB-related proteins can be detected in SRPs, and many proteins are positively responsive to ethylene stimulation. These results indicate that ethylene may stimulate latex production by regulating the accumulation of some key proteins. The phosphorylation modification of REF and SRPP isoforms might be crucial for NRB, and SRP may act as a complex natural rubber biosynthetic machine.


Assuntos
Antígenos de Plantas/genética , Hevea/genética , Látex/biossíntese , Proteínas de Plantas/genética , Sequência de Aminoácidos , Etilenos/metabolismo , Hevea/metabolismo , Proteoma/genética , Proteômica , Borracha/química , Borracha/metabolismo
4.
BMC Med Res Methodol ; 18(1): 96, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30249204

RESUMO

BACKGROUND: We are witnessing an exponential increase in the number of randomized controlled trials (RCTs) reported from mainland China. The increase is particularly notable in the field of new generation antidepressants and antipsychotics. Several previous studies have raised doubts regarding their quality. However, the quality of most recent RCTs published in China may have improved. METHODS: We searched RCTs that examined new generation antidepressants and antipsychotics published between 2013 and 2016 in the China National Knowledge Infrastructure (CNKI), the largest database of scientific publications in China. We interviewed the authors of a random subset of the identified references. We assessed the methodological rigor of each study based on the published reports and telephone interviews with the authors using six methodological domains adapted from the Cochrane's risk of bias tool. RESULTS: The final sample consisted of 138 studies, for which we interviewed 58 authors; the authors of 51 studies declined the interview, and the authors of 29 studies could not be contacted. The 51 studies with refused interviews were significantly less likely to be reported from university-affiliated hospitals and were less likely to be published in Chinese core journals. Based on the published reports, most of the 58 studies were assessed to be at unclear risk of bias in most methodological domains. After the interview, only 10 studies were assessed to be at low risk of bias for sequence generation and allocation concealment. Assuming that the studies for which the authors declined interviews had an unclear risk, the proportion of RCTs at low risk of bias in both sequence generation and allocation concealment was 9.2% (10/109, 95% confidence interval [CI]: 5.0 to 16.2). The interviews indicated that the studies were at high risk of bias for most of the other domains. CONCLUSION: In general, RCTs that evaluate new generation antidepressants or antipsychotics and are indexed in the CNKI continue to be of low quality. When conducting systematic reviews and meta-analyses in this field, it would be wise to include a specialist from China as a coresearcher to help assess the risk of bias in the identified studies.


Assuntos
Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Confiabilidade dos Dados , Bases de Dados Factuais/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , China , Humanos , Entrevistas como Assunto/estatística & dados numéricos , Publicações/normas , Publicações/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Projetos de Pesquisa/normas , Projetos de Pesquisa/tendências , Gestão da Qualidade Total/métodos , Gestão da Qualidade Total/normas , Gestão da Qualidade Total/tendências
5.
Int J Mol Sci ; 18(5)2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28468331

RESUMO

Rubber elongation factor (REF) and small rubber particle protein (SRPP) are two key factors for natural rubber biosynthesis. To further understand the roles of these proteins in rubber formation, six different genes for latex abundant REF or SRPP proteins, including REF138,175,258 and SRPP117,204,243, were characterized from Hevea brasiliensis Reyan (RY) 7-33-97. Sequence analysis showed that REFs have a variable and long N-terminal, whereas SRPPs have a variable and long C-terminal beyond the REF domain, and REF258 has a ß subunit of ATPase in its N-terminal. Through two-dimensional electrophoresis (2-DE), each REF/SRPP protein was separated into multiple protein spots on 2-DE gels, indicating they have multiple protein species. The abundance of REF/SRPP proteins was compared between ethylene and control treatments or among rubber tree clones with different levels of latex productivity by analyzing 2-DE gels. The total abundance of each REF/SRPP protein decreased or changed a little upon ethylene stimulation, whereas the abundance of multiple protein species of the same REF/SRPP changed diversely. Among the three rubber tree clones, the abundance of the protein species also differed significantly. Especially, two protein species of REF175 or REF258 were ethylene-responsive only in the high latex productivity clone RY 8-79 instead of in RY 7-33-97 and PR 107. Some individual protein species were positively related to ethylene stimulation and latex productivity. These results suggested that the specific protein species could be more important than others for rubber production and post-translational modifications might play important roles in rubber biosynthesis.


Assuntos
Etilenos/farmacologia , Hevea/efeitos dos fármacos , Látex/biossíntese , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Hevea/metabolismo , Proteínas de Plantas/genética , Proteoma/genética
6.
Electrophoresis ; 37(22): 2930-2939, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27699805

RESUMO

The extraction of high-purity proteins from the washing solution (WS) of rubber particles (also termed latex-producing organelles) from laticifer cells in rubber tree for proteomic analysis is challenging due to the low concentration of proteins in the WS. Recent studies have revealed that proteins in the WS might play crucial roles in natural rubber biosynthesis. To further examine the involvement of these proteins in natural rubber biosynthesis, we designed an efficiency method to extract high-purity WS proteins. We improved our current borax and phenol-based method by adding reextraction steps with phenol (REP) to improve the yield from low protein concentration samples. With this new method, we extracted WS proteins that were suitable for proteomics. Indeed, compared to the original borax and phenol-based method, the REP method improved both the quality and quantity of isolated proteins. By repeatedly extracting from low protein concentration solutions using the same small amount of phenol, the REP method yielded enough protein of sufficiently high-quality from starting samples containing less than 0.02 mg of proteins per milliliter. This method was successfully applied to extract the rubber particle proteins from the WS of natural rubber latex samples. The REP-extracted WS proteins were resolved by 2DE, and 28 proteins were positively identified by MS. This method has the potential to become widely used for the extraction of proteins from low protein concentration solutions for proteomic analysis.


Assuntos
Espectrometria de Massas/métodos , Proteínas de Plantas/análise , Proteínas de Plantas/isolamento & purificação , Proteômica/métodos , Borracha/química , Boratos , Fracionamento Químico , Eletroforese em Gel Bidimensional/métodos , Fenol
7.
Arch Phys Med Rehabil ; 95(8): 1585-93, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24662810

RESUMO

OBJECTIVE: To assess the efficacy of extracorporeal shockwave therapy (ESWT) and provide clinicians with an evidence base for their clinical decision making. DATA SOURCES: PubMed, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Evidence-Based Medicine Reviews. STUDY SELECTION: All randomized or quasi-randomized controlled trials of ESWT for chronic recalcitrant plantar fasciitis were searched. Searching identified 108 potentially relevant articles; of these, 7 studies with 550 participants met inclusion criteria. DATA EXTRACTION: Number of patients, population, body mass index, duration of symptoms, adverse effects, blinding method, and details of shockwave therapy were extracted. DATA SYNTHESIS: For intervention success rate, ESWT of low intensity was more effective than control treatment of low intensity. For pain relief, the pooled data showed a significant difference between the ESWT and control groups. For function, only low-intensity ESWT was significantly superior over the control treatment. CONCLUSIONS: The efficacy of low-intensity ESWT is worthy of recognition. The short-term pain relief and functional outcomes of this treatment are satisfactory. However, owing to the lack of a long-term follow-up, its long-term efficacy remains unknown.


Assuntos
Fasciíte Plantar/terapia , Ondas de Choque de Alta Energia/uso terapêutico , Manejo da Dor/métodos , Fasciíte Plantar/complicações , Humanos , Dor/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
ACS Omega ; 9(9): 10717-10726, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463267

RESUMO

With the severe depletion of coarse flake graphite (a critical raw material) resources, developing and utilizing fine and ultrafine graphite resources have recently attracted attention. Froth flotation is a widely used technique for the initial enrichment of graphite; however, the flotation selectivity decreases significantly along with particle size reduction. Ultrasound pretreatment would be a promising method to improve the flotation of fine particles. As an innovative approach to understand better the flotation response of different flake graphite sizes, this study conducted a comparative analysis based on flotation concentrate yield and ash as well as ash removal rate between the flake graphite with various particle sizes after ultrasound pretreatment. Particle size, X-ray powder diffraction, and scanning electron microscopy and energy dispersive X-ray spectroscopy analyses were used to investigate the effect of ultrasound treatment on mineralogical properties of the flake graphite with varied particle sizes. Process outcomes indicated that the flotation performance of fine flake graphite (mean chord length: 62.63 µm) was significantly enhanced after ultrasound pretreatment. However, flotation of the ultrafine flake graphite (mean chord length: 24.97 µm) after ultrasound treatment was limited due to the difficulty of generating sufficient fragmentation and dissociation by microjets and shock waves formed by the cavitation effect. Compared with conventional flotation, the concentrate yield of ultrasound flotation increased from 88.95 to 94.98%, ash content decreased from 5.72 to 4.87%, and ash removal rate enhanced from 36.94 to 42.61%. Particle size and mineral property analyses confirmed that further crushing and dissociation of the larger flake graphite after ultrasound pretreatment would be the main factors contributing to improved flotation performance. Additionally, the formation of air flocs in the coarse flake graphite during the ultrasound pretreatment process facilitated the flotation recovery of the crushed graphite particles.

9.
Waste Manag ; 184: 120-131, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815286

RESUMO

The recycling of spent lithium-ion batteries (LIBs) can not only reduce the potential harm caused by solid waste piles to the local environment but also provide raw materials for manufacturing new batteries. Flotation is an alternative approach to achieve the selective separation of cathode and anode active materials from spent LIBs. However, the presence of organic binder on the surface of hydrophilic lithium transition-metal oxides results in losses of cathode materials in the froth phase. In this study, plasma treatment was utilized to remove organic layers from cathode and anode active materials. Firstly, the correlations between plasma treatment parameters (e.g., input power, air flowrate, and treatment time) were explored and the contact angles of cathode and anode active materials were investigated by the response surface methodology. Secondly, differences in the flotation recoveries of cathode and anode active materials were enhanced with plasma modification prior to flotation, which is consistent with the contact angle measurement. Finally, the plasma-modification mechanisms of hydrophobicity of cathode and anode active materials were discussed according to Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The proposed method could be a promising tool to enhance the flotation separation efficiency of cathode and anode active materials for the recycling of spent LIBs.


Assuntos
Fontes de Energia Elétrica , Eletrodos , Interações Hidrofóbicas e Hidrofílicas , Lítio , Reciclagem , Lítio/química , Reciclagem/métodos , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduo Eletrônico
10.
J Proteome Res ; 12(11): 5146-59, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23991906

RESUMO

Lutoids are specific vacuole-based organelles within the latex-producing laticifers in rubber tree Hevea brasiliensis. Primary and secondary lutoids are found in the primary and secondary laticifers, respectively. Although both lutoid types perform similar roles in rubber particle aggregation (RPA) and latex coagulation, they vary greatly at the morphological and proteomic levels. To compare the differential proteins and determine the shared proteins of the two lutoid types, a proteomic analysis of lutoid membranes and inclusions was performed, revealing 169 proteins that were functionally classified into 14 families. Biological function analysis revealed that most of the proteins are involved in pathogen defense, chitin catabolism, and proton transport. Comparison of the gene and protein changed patterns and determination of the specific roles of several main lutoid proteins, such as glucanase, hevamine, and hevein, demonstrated that Chitinase and glucanase appeared to play crucial synergistic roles in RPA. Integrative analysis revealed a protein-based metabolic network mediating pH and ion homeostasis, defense response, and RPA in lutoids. From these findings, we developed a modified regulation model for lutoid-mediated RPA that will deepen our understanding of potential mechanisms involved in lutoid-mediated RPA and consequent latex coagulation.


Assuntos
Regulação Enzimológica da Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Glicosídeo Hidrolases/metabolismo , Hevea/genética , Lisossomos/enzimologia , Proteínas de Membrana/metabolismo , Borracha/metabolismo , Análise de Variância , Western Blotting , China , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Hevea/enzimologia , Lisossomos/genética , Microscopia Confocal , Microscopia Eletrônica , Modelos Biológicos , Proteômica/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas em Tandem
11.
Physiol Meas ; 44(4)2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-37015230

RESUMO

Objective. Dynamic cerebral autoregulation (dCA) is a well-established mechanism that acts to maintain cerebral blood flow (CBF) reasonably constant in response to short-term fluctuations in blood pressure. It is known to be impaired in many clinical conditions, including stenosis, which is also a major risk factor for ischaemic stroke. However, it is not yet well understood whether impairment in dCA in one brain region is independent or not on dCA impairment in other brain regions, for example, whether there are spatial effects of stenosis on dCA. This is due to the complex blood flow environment and the lack of physiological experiments.Approach. We thus establish and apply a novel computational stenosis model including the circle of Willis to investigate and to quantify the degree of dCA impairment and CBF patterns as a function of stenosis fraction, measured in different configurations of the cerebral vasculature.Main results. We find some evidence for dependence between dCA in different brain regions, although this is very preliminary and much more experimental data will be required to answer this question fully.Significance.Our study has provided a first attempt to consider the effect of stenosis in various arteries on cerebral autoregulation to investigate spatial variations in dCA. This has potential applications in the treatment of cerebrovascular diseases where the control of cerebral perfusion is critical but where measurements are scarce.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Constrição Patológica , Encéfalo , Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/fisiologia , Homeostase/fisiologia
12.
Int J Biol Macromol ; 231: 123358, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36693602

RESUMO

Separation of nucleic acids and proteins using gels has always been a crucial part of molecular biology research. For low-molecular-weight nucleic acids and proteins, low- and medium-concentration agarose gels cannot achieve the high resolution as polyacrylamide gels. We found that 6 %-14 % high-concentration agarose gels (HAGs) could be easily dissolved in an autoclave and the vertical gel cast can be effortlessly filled using an easy-made plastic box. Coupled with the improved buffer condition, HAG electrophoresis resulted in a good resolution of DNA and protein bands. With conventional TBE buffer plus 0.2 % NaCl, DNA fragments that differ by 2-5-bp within the 50-200-bp size range can be resolved on 6 %-8 % HAGs. By using TBE without NaCl, DNA fragments that differ by 2-bp or 2-nt within the 10-100-bp size range can be well resolved on >8 % HAGs. Using a buffer system comprising 1 M Tris-Cl for gel preparation, 0.2 M Tris-Cl/0.2 % SDS as upper tank buffer, and 0.2 M Tris-Cl as the lower tank buffer, HAGs achieved good molecular weight separation of total bacterial and plant proteins in the 10-200 kDa range. In conclusion, we developed a method for HAG preparation and electrophoresis of low-molecular-weight nucleic acids and proteins.


Assuntos
Ácidos Nucleicos , Peso Molecular , Sefarose , Eletroforese em Gel de Ágar/métodos , Cloreto de Sódio , Proteínas/análise , DNA , Géis , Eletroforese em Gel de Poliacrilamida
13.
Ultrason Sonochem ; 99: 106551, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37579658

RESUMO

Ultrasound has emerged as a promising technique for improving the mineral flotation performance. However, limited research exists regarding the influence of different ultrasound types on the flotation process. Specifically, the impact of combined ultrasound and the comparison of horn- and bath-type ultrasounds on flotation have not been fully investigated. To address this knowledge gap, a comprehensive study to explore the effects of different ultrasonic pretreatments on the flotation of flake graphite was conducted. A Box-Behnken design is employed to analyze the effects of combined ultrasound on graphite flotation. By characterizing the properties of graphite samples before and after the ultrasonic treatment, the aim is to elucidate the mechanism underlying the impact of ultrasound on graphite flotation. The experimental results indicated that the ultrasonic cavitation intensity exerted a significant influence on the graphite flotation recovery. Both horn- and bath- type ultrasounds contributed to flotation, but horn-type ultrasound demonstrated a more pronounced effect, leading to a 7% increase in flotation recovery, whereas bath-type ultrasound resulted in only a 2% increase. Furthermore, the cavitation intensity of combined ultrasound was found to be higher than that of single-frequency ultrasound in the same duration. However, the performance of graphite flotation was better with short duration combined ultrasound pretreatment, while the opposite trend was observed for a long duration ultrasound pretreatment. These findings may inform the development of more efficient and effective ultrasonic pretreatments for flotation separation processes.

14.
Plants (Basel) ; 12(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37111823

RESUMO

SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment protein receptors) are engines for almost all of the membrane fusion and exocytosis events in organism cells. In this study, we identified 84 SNARE genes from banana (Musa acuminata). Gene expression analysis revealed that the expression of MaSNAREs varied a lot in different banana organs. By analyzing their expression patterns under low temperature (4 °C), high temperature (45 °C), mutualistic fungus (Serendipita indica, Si) and fungal pathogen (Fusarium oxysporum f. sp. Cubense Tropical Race 4, FocTR4) treatments, many MaSNAREs were found to be stress responsive. For example, MaBET1d was up-regulate by both low and high temperature stresses; MaNPSN11a was up-regulated by low temperature but down-regulated by high temperature; and FocTR4 treatment up-regulated the expression of MaSYP121 but down-regulated MaVAMP72a and MaSNAP33a. Notably, the upregulation or downregulation effects of FocTR4 on the expression of some MaSNAREs could be alleviated by priorly colonized Si, suggesting that they play roles in the Si-enhanced banana wilt resistance. Foc resistance assays were performed in tobacco leaves transiently overexpressing MaSYP121, MaVAMP72a and MaSNAP33a. Results showed that transient overexpression of MaSYP121 and MaSNPA33a suppressed the penetration and spread of both Foc1 (Foc Race 1) and FocTR4 in tobacco leaves, suggesting that they play positive roles in resisting Foc infection. However, the transient overexpression of MaVAMP72a facilitated Foc infection. Our study can provide a basis for understanding the roles of MaSNAREs in the banana responses to temperature stress and mutualistic and pathogenic fungal colonization.

15.
Ultrason Sonochem ; 95: 106415, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37098313

RESUMO

This study aimed to investigate the effect of ultrasonic power and temperature on the impurity removal rate during conventional and ultrasonic-assisted leaching of aphanitic graphite. The results showed that the ash removal rate increased gradually (∼50 %) with the increase in ultrasonic power and temperature but deteriorated at high power and temperature. The unreacted shrinkage core model was found to fit the experimental results better than other models. The Arrhenius equation was used to calculate the finger front factor and activation energy under different ultrasonic power conditions. The ultrasonic leaching process was significantly influenced by temperature, and the enhancement of the leaching reaction rate constant by ultrasound was mainly reflected in the increase of the pre-exponential factor A. Ultrasound treatment improved the efficiency of impurity mineral removal by destroying the inert layer formed on the graphite surface, promoting particle fragmentation, and generating oxidation radicals. The poor reactivity of hydrochloric acid with quartz and some silicate minerals is a bottleneck limiting the further improvement of impurity removal efficiency in ultrasound-assisted aphanitic graphite. Finally, the study suggests that introducing fluoride salts may be a promising method for deep impurity removal in the ultrasound-assisted hydrochloric acid leaching process of aphanitic graphite.

16.
iScience ; 26(6): 106871, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37275527

RESUMO

Emerging evidence shows that pancreatic ß-cell function and quality are key determinants in the progression of type 2 diabetes (T2D). The transcription factor zinc finger homeobox 2 (Zhx2) is involved in proliferation and development of multiple cells. However, the exact role of Zhx2 in ß-cells and T2D remains completely unknown. Here, we report that Zhx2 orchestrates ß-cell mass and function by regulating paired box protein pax-6 (Pax6). We found that ß-cell-specific knockout Zhx2 (Zhx2BKO) mice showed a decrease in ß-cell proliferation and glucose homeostasis. Under prediabetic and diabetic conditions, we discovered glucose intolerance in both Zhx2BKO-HFD mice and Zhx2BKO-db/db mice, with reduced ß-cell mass and insulin secretion. Mechanistically, we demonstrated that Zhx2 targeted the Pax6 promoter region (-1740∼-1563; -862∼-559; -251∼+75), enhanced promoter activity. Overall, Zhx2 maintains ß-cell function by transcriptionally regulating Pax6, which provides a therapeutic target for diabetes intervention.

17.
Cell Death Dis ; 14(2): 141, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36806050

RESUMO

Mitochondrial function and homeostasis are critical to the proliferation of lung cancer cells. T-cell immunoglobulin and mucin domain-containing molecule 4 (TIM-4) promotes the development and progression of lung cancer. However, the role of TIM-4 in mitochondria homeostasis in tumor cells remains completely unknown. In this study, we found that TIM-4 promoted growth and proliferation of lung cancer cells by the oxidative phosphorylation (OXPHOS) pathway. Consistently, inhibition of OXPHOS reversed TIM-4-induced proliferation of lung cancer cells. Notably, TIM-4 promoted mitochondrial fusion via enhancing L-OPA1 protein expression. Mechanistically, TIM-4 regulated protein of L-OPA1 through the PI3K/AKT pathway, and TIM-4 interacted with ANXA2 to promote the activation of PI3K/AKT signaling. Collectively, TIM-4 promotes oxidative phosphorylation of lung cancer cells to accelerate tumor progress via ANXA2/PI3K/AKT/OPA1 axis, which sheds significant new lights on the potential role of TIM-4 in regulating tumor cell metabolism.


Assuntos
Anexina A2 , Neoplasias Pulmonares , Humanos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Neoplasias Pulmonares/genética , Mitocôndrias , Homeostase , GTP Fosfo-Hidrolases
18.
Int J Biol Macromol ; 204: 661-676, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35181326

RESUMO

Fatty acid desaturase (FAD) plays important roles in plant growth and development and plant defense processes. In this study, we identified 27 MaFAD genes from the banana genome. According to the amino acid sequence similarities, their encoded proteins could be classified into five subfamilies. This classification is consistently supported by their gene and protein structures, conserved motifs and subcellular localizations. Segmental duplication events were found to play predominant roles in the MaFAD gene family expansion. Thirty miRNAs targeting MaFADs were identified and many hormone- and stress-responsive cis-acting elements and transcription factor binding sites (TFBSs) were identified in their promoters, indicating that the MaFADs expression regulation was very complicated. Gene expression analysis showed that some MaFADs showed significant differential expression in response to high and low temperature. FocTR4 influenced greatly the expression of several MaFADs and greatly induced the fatty acid (FA) accumulations in roots. Although S. indica showed no significant influence on the expression of most MaFADs, it could greatly alleviate the influence of FocTR4 on several MaFADs and FA biosynthesis. Our study revealed that MaFADs contributed greatly to the responses of high and low temperature stresses and mutualistic and parasitic fungi colonization in banana.


Assuntos
Musa , Flavina-Adenina Dinucleotídeo/metabolismo , Fungos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Família Multigênica , Musa/genética , Musa/metabolismo , Filogenia , Proteínas de Plantas/química , Estresse Fisiológico/genética , Temperatura
19.
Biology (Basel) ; 11(3)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35336767

RESUMO

Recently, many control methods have been tried and applied in the Fusarium wilt disease control of banana and have achieved definite progresses. In this study, by using 'Zhongjiao No.3' and 'Zhongjiao No.4' banana seedlings as materials, the effects of Serendipita indica and bamboo fungus (Dictyophorae echinovolvata) culture substrates on the growth and Fusarium wilt disease resistance of banana were investigated. Results showed that the plant height, leaf length, leaf width, root length and root thickness, aboveground part fresh weight, root fresh weight, and relative chlorophyll content and nitrogen content in leaves of banana seedlings colonized with S. indica were all greater than those of non-colonized controls, while these parameters of banana seedlings grown in nutrient soil containing D. echinovolvata culture substrates were significantly suppressed. Both S. indica non-colonized and colonized seedlings cultivated in nutrient containing 1/4 D. echinovolvata culture substrates showed much milder symptoms compared with those cultivated in normal nutrient soil, indicating that the addition of bamboo fungus substrates to the soil can enhance the Fusarium wilt resistance of banana. The results obtained in this study can provide a basis for the application of S. indica and bamboo fungus in the prevention and control of banana Fusarium wilt disease.

20.
Front Bioeng Biotechnol ; 10: 1051117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36507279

RESUMO

Salidroside, the main bioactive compound isolated from the plant source of Rhodiola rosea L, possesses broad-spectrum pharmacological activities, but suffers from the low cell membranes permeability and alimentary absorption due to its high polarity. Therefore, a whole-cell catalytic strategy for the synthesis of salidroside esters was explored to improve its lipophilicity. The results showed that Aspergillus oryzae demonstrated the highest biocatalytic activity among the microbial strains tested. For the synthesis of salidroside caprylate, the optimum conditions of reaction medium, Aspergillus oryzae amount, molar ratio of vinyl caprylate to salidroside and reaction temperature were acetone, 30 mg/ml, 10°C and 40°C, respectively. Under these conditions, the initial reaction rate was 15.36 mM/h, and substrate conversion and regioselectivity all reached 99%. Moreover, the results indicated that although various 6'-monoesters derivatives of salidroside were exclusively obtained with excellent conversions (96%-99%), the reaction rate varied greatly with different chain-length acyl donors. This study details an efficient and cost-effective biocatalytic approach for the synthesis of salidroside esters by using Aspergillus oryzae as a catalyst for the first time. Considering the whole cell catalytic efficiency and operational stability, this strategy may provide a new opportunity to develop green industrial processes production for ester derivatives of salidroside and its analogues.

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