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1.
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
2.
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.

3.
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.

4.
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.

5.
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.

6.
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.

7.
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
8.
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
9.
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
10.
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
11.
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.

12.
Plants (Basel) ; 11(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36297775

RESUMO

Tea plant is susceptible to low temperature, while the cold injury recovery mechanisms of tea leaves are still unclear. Windbreak has an effective and gradient range of protecting tea plants. Tea plants with increasing cold damage degree have varying recovery status accordingly, which are the ideal objects for investigating the cold injury recovery mechanisms of tea leaves. Here, we investigated the transcriptome and phytohormone profiles of tea leaves with different cold injury degrees in recovery (adjacent to the windbreak), and the levels of chlorophylls, malondialdehyde, major phytohormones as well as the activities of peroxidase (POD) and superoxide dismutase (SOD) were also measured. The results showed the content of total chlorophylls and the activity of POD in mature tea leaves gradually decreased with the distance to windbreak, while SOD showed the opposite. The major phytohormones were highly accumulated in the moderately cold-injured tea leaves. The biosynthesis of abscisic acid (ABA) was enhanced in the moderate cold damaged tea leaves, suggesting that ABA plays an important role in the cold response and resistance of tea plants. The transcriptomic result showed that the samples in different rows were well discriminated, and the pathways of plant-pathogen interaction and flavonoid biosynthesis were enriched based on KEGG analysis. WRKY, GRAS and NAC were the top classes of transcription factors differentially expressed in the different cold-injured tea leaves. Thus, windbreak is effective to protect adjacent tea plants from cold wave, and phytohormones importantly participate in the cold injury recovery of tea leaves.

13.
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.

14.
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
15.
Microbiol Spectr ; 10(1): e0278021, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35196796

RESUMO

Understanding the immune response to severe acute respiratory syndrome coronavirus (SARS-CoV-2) is critical to overcome the current coronavirus disease (COVID-19) pandemic. Efforts are being made to understand the potential cross-protective immunity of memory T cells, induced by prior encounters with seasonal coronaviruses, in providing protection against severe COVID-19. In this study we assessed T-cell responses directed against highly conserved regions of SARS-CoV-2. Epitope mapping revealed 16 CD8+ T-cell epitopes across the nucleocapsid (N), spike (S), and open reading frame (ORF)3a proteins of SARS-CoV-2 and five CD8+ T-cell epitopes encoded within the highly conserved regions of the ORF1ab polyprotein of SARS-CoV-2. Comparative sequence analysis showed high conservation of SARS-CoV-2 ORF1ab T-cell epitopes in seasonal coronaviruses. Paradoxically, the immune responses directed against the conserved ORF1ab epitopes were infrequent and subdominant in both convalescent and unexposed participants. This subdominant immune response was consistent with a low abundance of ORF1ab encoded proteins in SARS-CoV-2 infected cells. Overall, these observations suggest that while cross-reactive CD8+ T cells likely exist in unexposed individuals, they are not common and therefore are unlikely to play a significant role in providing broad preexisting immunity in the community. IMPORTANCE T cells play a critical role in protection against SARS-CoV-2. Despite being highly topical, the protective role of preexisting memory CD8+ T cells, induced by prior exposure to circulating common coronavirus strains, remains less clear. In this study, we established a robust approach to specifically assess T cell responses to highly conserved regions within SARS-CoV-2. Consistent with recent observations we demonstrate that recognition of these highly conserved regions is associated with an increased likelihood of milder disease. However, extending these observations we observed that recognition of these conserved regions is rare in both exposed and unexposed volunteers, which we believe is associated with the low abundance of these proteins in SARS-CoV-2 infected cells. These observations have important implications for the likely role preexisting immunity plays in controlling severe disease, further emphasizing the importance of vaccination to generate the immunodominant T cells required for immune protection.


Assuntos
COVID-19/imunologia , Epitopos de Linfócito T/imunologia , SARS-CoV-2/imunologia , Sequência de Aminoácidos , Linfócitos T CD8-Positivos/imunologia , COVID-19/genética , COVID-19/virologia , Sequência Conservada , Coronavirus/química , Coronavirus/classificação , Coronavirus/genética , Coronavirus/imunologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Reações Cruzadas , Mapeamento de Epitopos , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Humanos , Células T de Memória/imunologia , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
16.
Med Eng Phys ; 95: 51-63, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34479693

RESUMO

The mechanism of cerebral autoregulation ensures a continuous and sufficient blood supply to the brain to maintain normal function in the presence of changes in blood pressure. Impaired cerebral autoregulation is implicated in a range of brain diseases. We thus present here a multiscale model of cerebral autoregulation to provide a more detailed basis for a better understanding of the mechanisms behind impaired autoregulation. This model is built around a model of single arteriole, which includes a model of Nitric Oxide (NO) transport, the myogenic response, and a 4-state kinetic model coupled to a mechanical model of the vessel wall. In particular, the NO component of the model is added here to better understand the interaction mode between NO and the myogenic response, since the role of NO, the recognized effective vasodilator, is poorly understood in this context. This vessel model is then integrated within a model of the full-brain vasculature. The model is validated using a range of experimental data from the literature, both steady-state and dynamic. The model is able to predict the response of the arteriole to changes in both driving pressure and baseline pressure, indicating that the model captures well the balance between the myogenic and metabolic mechanisms. We next plan to examine the ways in which impaired autoregulation is manifested in different patient groups, potentially leading to improved therapy.


Assuntos
Encéfalo , Óxido Nítrico , Pressão Sanguínea , Circulação Cerebrovascular , Homeostase , Humanos
17.
Orthop Surg ; 12(6): 1882-1889, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33112035

RESUMO

OBJECTIVES: Plantar fasciitis (PF) is the most common cause of heel pain. Though PF is self-limited, it can develop into chronic pain and thus treatment is needed. Early and accurate prognostic assessment of patients with PF is critically important for selecting the optimal treatment pathway. Nevertheless, there is no scoring system to determine the severity of PF and no prognostic model in choosing between conservative or surgical treatment. The study aimed to develop a novel scoring system to evaluate the severity of plantar fasciitis and predict the prognosis of conservative treatment. METHODS: Data of consecutive patients treated from 2014 to 2018 were retrospectively collected. One hundred and eighty patients were eligible for the study. The demographics and clinical characteristics served as independent variables. The least follow-up time was 6 months. A minimal reduction of 60% in the visual analog scale (VAS) score from baseline was considered as minimal clinically important difference (MCID). Those factors significantly associated with achieving MCID in univariate analyses were further analyzed by multivariate logistic regression. A novel scoring system was developed using the best available literature and expert-opinion consensus. Inter-observer reliability and intra-observer reproducibility were evaluated. The appropriate cut-off points for the novel score system were obtained using receiver operating characteristic (ROC) curves. RESULTS: The system score = VAS (0-3 point = 1; 3.1-7 point = 3; 7.1-10 point = 5) + duration of symptoms (<6 months = 1; ≥1 6 months = 2) + ability to walk without pain (>1 h = 1; ≤1 h = 4) + heel spur in X-ray (No = 0; Yes = 2) + high intensity zone (HIZ) in MRI (No = 0; Yes = 2). The total score was divided in four categories of severity: mild (2-4 points), moderate (5-8 points), severe (9-12 points), and critical (13-15 points). Inter-observer agreement with a value of 0.84 was considered as perfect reliability. Intra-observer reproducibility with a value of 0.92 was considered as perfect reproducibility. The optimum cut-off value was 10 points. The sensitivity of predictive factors was 86.37%, 84.21%, 91.22%, 84.12%, and 89.32%, respectively; the specificity was 64.21%, 53.27%, 67.76%, 62.37%, and 79.58%, respectively; the area under curve was 0.75, 0.71, 0.72, 0.87, and 0.77, respectively. The Hosmer-Lemeshow test showed a good fitting of the score system with an overall accuracy of 90.6%. CONCLUSIONS: Based on prognostic factors, the present study establishes a novel scoring system which is highly comprehensible, reliable, and reproducible. This score system can be used to identify the severity of plantar fasciitis and predict the prognosis of conservative treatment accurately. The application of this scoring system in clinical settings can significantly improve the decision-making process.


Assuntos
Tomada de Decisões , Fasciíte Plantar/classificação , Fasciíte Plantar/terapia , Medição da Dor/normas , Medidas de Resultados Relatados pelo Paciente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos
18.
Biomolecules ; 10(10)2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050283

RESUMO

Banana Fusarium wilt (BFW), which is one of the most important banana diseases worldwide, is mainly caused by Fusarium oxysporum f. sp. cubense tropic race 4 (Foc TR4). In this study, we conducted secretome analysis of Foc R1 and Foc TR4 and discovered a total of 120 and 109 secretory proteins (SPs) from Foc R1 cultured alone or with banana roots, respectively, and 129 and 105 SPs respectively from Foc TR4 cultured under the same conditions. Foc R1 and Foc TR4 shared numerous SPs associated with hydrolase activity, oxidoreductase activity, and transferase activity. Furthermore, in culture with banana roots, Foc R1 and Foc TR4 secreted many novel SPs, of which approximately 90% (Foc R1; 57/66; Foc TR4; 50/55) were unconventional SPs without signal peptides. Comparative analysis of SPs in Foc R1 and Foc TR4 revealed that Foc TR4 not only generated more specific SPs but also had a higher proportion of SPs involved in various metabolic pathways, such as phenylalanine metabolism and cysteine and methionine metabolism. The cysteine biosynthesis enzyme O-acetylhomoserine (thiol)-lyase (OASTL) was the most abundant root inducible Foc TR4-specific SP. In addition, knockout of the OASTL gene did not affect growth of Foc TR4; but resulted in the loss of pathogenicity in banana 'Brazil'. We speculated that OASTL functions in banana by interfering with the biosynthesis of cysteine, which is the precursor of an enormous number of sulfur-containing defense compounds. Overall, our studies provide a basic understanding of the SPs in Foc R1 and Foc TR4; including a novel effector in Foc TR4.


Assuntos
Carbono-Oxigênio Liases , Fusarium/patogenicidade , Musa/microbiologia , Proteoma/metabolismo , Carbono-Oxigênio Liases/genética , Carbono-Oxigênio Liases/isolamento & purificação , Carbono-Oxigênio Liases/metabolismo , Fusarium/química , Fusarium/genética , Fusarium/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Organismos Geneticamente Modificados , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Proteoma/análise , Proteoma/genética , Via Secretória/genética , Transcriptoma , Virulência/fisiologia , Fatores de Virulência/genética , Fatores de Virulência/isolamento & purificação , Fatores de Virulência/metabolismo
19.
Ying Yong Sheng Tai Xue Bao ; 31(3): 1023-1032, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32538000

RESUMO

With survey data from three voyages in the summer of 2014, 2016, and 2017, spatial distribution and inter-annual variability of spawning grounds of Cynoglossus joyneri in the coastal waters of Yellow Sea were examined based on Tweedie-generalized additive model (GAM). The results showed that the spawning grounds of C. joyneri mainly distributed in the Haizhou Bay ranging within 34°00'-35°18' N, 119°30'-121°30' E. The other one in Subei Shoal 32°18'-34°00' N, 120°18'-122°00' E. Fish eggs of C. joyneri were few in the southern waters of Shandong Peninsula 34°42'-36°48' N, 119°30'-122°00' E. The distribution of fish eggs was significantly related to the location (i.e., longitude and latitude), depth, and sea surface temperature, and did not relate to the sea surface salinity and surface chlorophyll a. The optimal range of depth, sea surface temperature, sea surface salinity, and surface chlorophyll a were 15-26 m, 29-32 ℃, 22-25 and 0.10-3 mg·m-3, respectively. There was notable inter-annual variability in the spatial distribution of spawning grounds of C. joyneri and its influencing factors. Overall, the distribution of spawning grounds is relatively stable, but potentially move northward in the year with high sea surface temperature.


Assuntos
Clorofila A , Peixes , Animais , Salinidade , Estações do Ano , Temperatura
20.
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
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