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1.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928505

RESUMO

Nannochloropsis gaditana, a microalga known for its photosynthetic efficiency, serves as a cell factory, producing valuable biomolecules such as proteins, lipids, and pigments. These components make it an ideal candidate for biofuel production and pharmaceutical applications. In this study, we genetically engineered N. gaditana to overexpress the enzyme fructose-1,6-bisphosphatase (cyFBPase) using the Hsp promoter, aiming to enhance sugar metabolism and biomass accumulation. The modified algal strain, termed NgFBP, exhibited a 1.34-fold increase in cyFBPase activity under photoautotrophic conditions. This modification led to a doubling of biomass production and an increase in eicosapentaenoic acid (EPA) content in fatty acids to 20.78-23.08%. Additionally, the genetic alteration activated the pathways related to glycine, protoporphyrin, thioglucosides, pantothenic acid, CoA, and glycerophospholipids. This shift in carbon allocation towards chloroplast development significantly enhanced photosynthesis and growth. The outcomes of this study not only improve our understanding of photosynthesis and carbon allocation in N. gaditana but also suggest new biotechnological methods to optimize biomass yield and compound production in microalgae.


Assuntos
Biomassa , Frutose-Bifosfatase , Metabolômica , Microalgas , Fotossíntese , Estramenópilas , Frutose-Bifosfatase/metabolismo , Frutose-Bifosfatase/genética , Estramenópilas/genética , Estramenópilas/metabolismo , Estramenópilas/crescimento & desenvolvimento , Estramenópilas/enzimologia , Microalgas/metabolismo , Microalgas/genética , Microalgas/crescimento & desenvolvimento , Microalgas/enzimologia , Metabolômica/métodos , Citosol/metabolismo
2.
J Biol Chem ; 298(6): 102054, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35598826

RESUMO

Myosins belong to a large superfamily of actin-dependent molecular motors. Nonmuscle myosin II (NM II) is involved in the morphology and function of neurons, but little is known about how NM II activity is regulated. Brain-derived neurotrophic factor (BDNF) is a prevalent neurotrophic factor in the brain that encourages growth and differentiation of neurons and synapses. In this study, we report that BDNF upregulates the phosphorylation of myosin regulatory light chain (MLC2), to increases the activity of NM II. The role of BDNF on modulating the phosphorylation of MLC2 was validated by using Western blotting in primary cultured hippocampal neurons. This result was confirmed by injecting BDNF into the dorsal hippocampus of mice and detecting the phosphorylation level of MLC2 by Western blotting. We further perform coimmunoprecipitation assay to confirm that this process depends on the activation of the LYN kinase through binding with tyrosine kinase receptor B, the receptor of BDNF, in a kinase activity-dependent manner. LYN kinase subsequently phosphorylates MLCK, further promoting the phosphorylation of MLC2. Taken together, our results suggest a new molecular mechanism by which BDNF regulates MLC2 activity, which provides a new perspective for further understanding the functional regulation of NM II in the nervous system.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Cadeias Leves de Miosina , Miosina Tipo II , Quinase de Cadeia Leve de Miosina , Quinases da Família src , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Hipocampo/metabolismo , Camundongos , Cadeias Leves de Miosina/metabolismo , Miosina Tipo II/metabolismo , Quinase de Cadeia Leve de Miosina/química , Neurônios/metabolismo , Fosforilação , Quinases da Família src/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38871196

RESUMO

PURPOSE: With the coming era of digital medicine and healthcare technology, mathematical modeling of tumors has become a key step to optimize and realize precision radiation therapy. The purpose of this study was to develop a mathematical model for simulating the change of head and neck (HN) tumor volume during radiation therapy. METHODS AND MATERIALS: A formula was developed to describe the dynamic change of oxygenated compartment within a tumor, which was combined with the lethal lesions model to describe various cell processes during radiation therapy, including potentially lethal lesion repair and misrepair, cell proliferation/loss, and tumor reoxygenation. Parameter sensitivity analysis was performed to evaluate the impacts of lesion- and repair-related biological factors on radiation therapy outcomes. RESULTS: We tested our model on 14 available patients with HN cancer and compared the performance with 3 other models. The mean error of our model for the 12 good fit cases was 12.2%, which is considerably smaller than that of the linear quadratic model (19.7%), the generalized linear quadratic model (19.1%), and a 4-level cell population model (16.6%). Correlation analysis results revealed that for small tumors, there was a positive correlation (correlation coefficient r=0.9416) between hypoxic fraction (hf) and tumor volume, whereas the correlation became negative and not significant (r=-0.4365) for large tumors. It is demonstrated from sensitivity analysis that the production rate of lethal lesions (ηl) has a far greater impact on tumor volume than other parameters. The hf had an insignificant impact on tumor volume but had a notable influence on the volume of surviving cells. The final volume of surviving cells athf=0.5 was almost 8 ×102 times that of hf=0.01. The potentially lethal lesion-related parameters (the production rate of potentially lethal lessions per unit dose ηpl, the rate of correct repair per unit time εpl, and the rate of binary misrepair per unit time ε2pl) had rather small impacts (<1%) on both tumor volume and the volume of surviving cells, which indicates that the repaired and misrepaired sublethal cells only take up a small portion of the total cancer cell population. CONCLUSIONS: A population-based tumor-volume model for HN cancer during radiation therapy with a dynamic oxygenated compartment was developed in this study. Comprehensively considering the damage process of tumor cells caused by radiation therapy, the accurate prediction of the volume change of HN tumors during treatment was revealed. Meanwhile, various cell activities and their principles in the process of antitumor treatment were reflected, which has positive clinical reference significance for radiobiology.

4.
Chempluschem ; : e202400240, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949230

RESUMO

Lithium-ion batteries (LIBs) are widely used in electric vehicles, portable electronic devices, clean energy storage, and other fields due to their long service life, high energy density, and low self-discharge rate, which also puts forward higher requirements for the performance of lithium-ion batteries. As an anode for lithium-ion batteries, SiO materials have garnered significant attention from researchers due to its high specific capacity (2400 mAh·g-1), abundance of raw materials, and simple preparation. However, its large volume change (~ 200%) and poor electrical conductivity hinder its large-scale commercial application. Researchers employ various methods to reduce the volume change of SiO during lithium intercalation and improve its structural stability during cycling. This work mainly reviews the chemical structure and lithium storage mechanism of SiO, as well as the latest research progress on the preparation methods of SiO/C anode materials, focusing on summarizing the following preparation strategies: chemical vapor deposition, mechanical ball milling, spray drying, and in-situ reduction/oxidation methods. The obtained SiO-based anode materials' structural characteristics and electrochemical properties are compared and summarized. Finally, this review discusses the advantages and disadvantages of the current preparation methods, the future research directions, and the development prospects of SiO-based anode materials.

5.
Dalton Trans ; 53(26): 10866-10874, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38873998

RESUMO

Vanadate electrodes are potential candidates for lithium-ion batteries (LIBs) due to their large theoretical specific capacity. However, their easy dissolution in the electrolyte, large structural changes, low conductivity and capacity decay during cycling hinder their further application. Herein, a lithium-ion battery electrode of Na5V12O32 (NVO) nanowires covered with a carbon film and formed by the reconstruction of carbon quantum dots (CDs) was obtained using an in situ capping strategy. Remarkably, the carbon film could prevent direct contact between the NVO nanowires and the electrolyte, thus slowing down the occurrence of side reactions and avoiding the dissolution of the NVO nanowires. Among the electrodes treated at different temperatures, the C@NVO-400 electrode exhibits high capacity and excellent cycling stability as the electrode of LIBs, with a discharge specific capacity of 779.1 and 315.5 mAh g-1 after 400 and 1000 cycles at a current density of 0.1 and 2 A g-1, respectively. An in situ coating strategy is proposed here to contribute to the further development of coated vanadate electrodes for high-performance LIBs.

6.
Abdom Radiol (NY) ; 49(3): 814-822, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38150141

RESUMO

BACKGROUND: To determine the utility of virtual-monoenergetic imaging (VMI) at low energy levels from contrast-enhanced dual-layer dual-energy (DLDE) computed tomography enterography (CTE) in the preoperative assessment of internal penetrating lesions of Crohn's disease (CD). MATERIALS AND METHODS: Thirty-eight patients with penetrating lesions of CD by surgery undergoing contrast-enhanced DLDE CTE were retrospectively included. Polyenergetic imaging (PEI) and VMIs at low energy levels [40-70 kiloelectron volts (keV)] with 10 keV intervals were reconstructed. The objective parameters of image quality [noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)] and the subjective parameter of image quality [diagnostic performance of lesions (DPL), overall image quality(OIQ)] of PEI and all VMIs at the low energy level were compared to determine the VMI on the optimal energy level. The lesion detection capability between PEI and the optimal VMI was compared. RESULTS: VMI40 was determined to be the optimal VMI among all VMIs at the low energy level for owning the best image quality. No significant difference was found in the detecting capability in penetrating lesions between VMI40 and PEI (p = 1.0), whereas a significant difference was found in the detecting capability in the bowel origin of the penetrating lesions (p = 0.004), the involved organ or structure by the fistula (p = 0.016) and the orifice of the fistula connected to the involved organ or structure ( p = 0.031) between them. CONCLUSIONS: Compared to conventional PEI, VMI40 improves the detection capability in anatomical details of penetrating lesions of CD, helping colorectal surgeons rationalizing preoperative plans of internal penetrating lesions of CD.


Assuntos
Doença de Crohn , Fístula , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Humanos , Doença de Crohn/diagnóstico por imagem , Doença de Crohn/cirurgia , Estudos Retrospectivos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Razão Sinal-Ruído , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
7.
Front Pharmacol ; 15: 1367358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410130

RESUMO

Prostatic cancer (PCa) is a common malignant neoplasm in men worldwide. Most patients develop castration-resistant prostate cancer (CRPC) after treatment with androgen deprivation therapy (ADT), usually resulting in death. Therefore, investigating new therapeutic targets and drugs for PCa patients is urgently needed. Nuclear Dbf2-related kinase 1 (NDR1), also known as STK38, is a serine/threonine kinase in the NDR/LATS kinase family that plays a critical role in cellular processes, including immunity, inflammation, metastasis, and tumorigenesis. It was reported that NDR1 inhibited the metastasis of prostate cancer cells by suppressing epithelial-mesenchymal transition (EMT), and decreased NDR1 expression might lead to a poorer prognosis, suggesting the enormous potential of NDR1 in antitumorigenesis. In this study, we characterized a small-molecule agonist named aNDR1, which specifically bound to NDR1 and potently promoted NDR1 expression, enzymatic activity and phosphorylation. aNDR1 exhibited drug-like properties, such as favorable stability, plasma protein binding capacity, cell membrane permeability, and PCa cell-specific inhibition, while having no obvious effect on normal prostate cells. Meanwhile, aNDR1 exhibited good antitumor activity both in vitro and in vivo. aNDR1 inhibited proliferation and migration of PCa cells and promoted apoptosis of PCa cells in vitro. We further found that aNDR1 inhibited subcutaneous tumors and lung metastatic nodules in vivo, with no obvious toxicity to the body. In summary, our study presents a potential small-molecule lead compound that targets NDR1 for clinical therapy of PCa patients.

8.
Int J Endocrinol ; 2022: 7808393, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35265126

RESUMO

Background: Irisin, an exercise-induced myokine and adipocytokine, has been reported to decrease in type 2 diabetic patients. Recently, several research studies indicated that circulating levels were correlated with bone mineral density (BMD). To evaluate bone metabolism, bone turnover markers (BTMs) should be included. However, with respect to newly diagnosed T2DM patients, the relevance of their irisin levels to their BTMs and BMD remains unclear. The investigation of serum irisin levels in patients who have been newly diagnosed with type 2 diabetes and illumination of the relationship between serum irisin levels and those two indices of BMD and BTMs mentioned above are the intention of this cross-sectional study. Methods: 66 new-onset type 2 diabetic patients (T2DM group), together with 82 control subjects (NGT group), were recruited in this study. Serum irisin concentrations and BTMs (including osteocalcin (OC), procollagen type 1 N-terminal propeptide (P1NP), and ß-C-terminal telopeptides of type I collagen (ß-CTX)) were determined by the enzyme-linked immunosorbent assay (ELISA). Glucose, lipid profile, and insulin were considered as measuring indicators as well. Dual-energy X-ray absorptiometry (DXA) was utilized to evaluate the indicator of BMD. Serum irisin, BTMs, and BMD were compared between diabetic patients and healthy individuals. Pearson and Spearman correlation analyses were applied as well to assess correlations between irisin and BTMs and BMD. Multiple stepwise regression analysis was conducted to identify the independent factors of irisin. ROC curve analyses were carried out for serum irisin prediction for osteoporosis/osteopenia (OP). Results: The serum levels of irisin, procollagen type 1, intact N-terminal propeptide (P1NP), and osteocalcin (OC) were evidently lower in T2DM subjects than in NGT subjects (10.90 ± 1.88 vs .11.69 ± 2.06 ng/mL, P < 0.05; 36.42(25.68,51.70) vs. 44.52(35.73,58.05)ng/ml, P < 0.05; 16.15(12.40,21.66) vs. 18.70(15.56, 23.22)ng/ml, P < 0.05). Among patients with T2DM, the circulating irisin level of those with OP was lower than that of normal BMD (9.98 ± 2.09 vs. 11.39 ± 1.57 ng/ml, P < 0.01); irisin had a negative correlation with ß-C-terminal telopeptides of type I collagen (ß-CTX) (r = -0.496, P < 0.001) and came back unrelated to Lumbar BMD; Lumbar BMD was negatively relevant to OC (r = -0.274, P < 0.05) and ß-CTX (r = -0.410, P < 0.01). Multiple linear regression analyses of stepwise models implied that TG, LDL-C, and ß-CTX were independently associated with serum irisin concentrations (P < 0.01 or P < 0.05). Conclusion: Serum irisin level was declined in patients with type 2 diabetes diagnosed in the near term and had a certain association with bone turnover markers. It is suggested to consider irisin as a potential biomarker of bone metabolic disorder in T2DM patients with the initial diagnosis.

9.
Front Microbiol ; 11: 1633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765463

RESUMO

Lignocellulose is an abundant waste resource and has been considered as a promising material for production of biofuels or other valuable bio-products. Currently, one of the major bottlenecks in the economic utilization of lignocellulosic materials is the cost-efficiency of converting lignocellulose into soluble sugars for fermentation. One way to address this problem is to seek superior lignocellulose degradation enzymes or further improve current production yields of lignocellulases. In the present study, the lignocellulose degradation capacity of a thermophilic fungus Chaetomium thermophilum was firstly evaluated and compared to that of the biotechnological workhorse Trichoderma reesei. The data demonstrated that compared to T. reesei, C. thermophilum displayed substantially higher cellulose-utilizing efficiency with relatively lower production of cellulases, indicating that better cellulases might exist in C. thermophilum. Comparison of the protein secretome between C. thermophilum and T. reesei showed that the secreted protein categories were quite different in these two species. In addition, to prove that cellulases in C. thermophilum had better enzymatic properties, the major cellulase cellobiohydrolase I (CBH1) from C. thermophilum and T. reesei were firstly characterized, respectively. The data showed that the specific activity of C. thermophilum CBH1 was about 4.5-fold higher than T. reesei CBH1 in a wide range of temperatures and pH. To explore whether increasing CBH1 activity in T. reesei could contribute to improving the overall cellulose-utilizing efficiency of T. reesei, T. reesei cbh1 gene was replaced with C. thermophilum cbh1 gene by integration of C. thermophilum cbh1 gene into T. reesei cbh1 gene locus. The data surprisingly showed that this gene replacement not only increased the cellobiohydrolase activities by around 4.1-fold, but also resulted in stronger induction of other cellulases genes, which caused the filter paper activities, Azo-CMC activities and ß-glucosidase activities increased by about 2.2, 1.9, and 2.3-fold, respectively. The study here not only provided new resources of superior cellulases genes and new strategy to improve the cellulase production in T. reesei, but also contribute to opening the path for fundamental research on C. thermophilum.

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