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1.
Cell Commun Signal ; 22(1): 212, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566100

RESUMO

The pathogenesis of Parkinson's disease (PD) is strongly associated with neuroinflammation, and type I interferons (IFN-I) play a crucial role in regulating immune and inflammatory responses. However, the specific features of IFN in different cell types and the underlying mechanisms of PD have yet to be fully described. In this study, we analyzed the GSE157783 dataset, which includes 39,024 single-cell RNA sequencing results for five PD patients and six healthy controls from the Gene Expression Omnibus database. After cell type annotation, we intersected differentially expressed genes in each cell subcluster with genes collected in The Interferome database to generate an IFN-I-stimulated gene set (ISGs). Based on this gene set, we used the R package AUCell to score each cell, representing the IFN-I activity. Additionally, we performed monocle trajectory analysis, and single-cell regulatory network inference and clustering (SCENIC) to uncover the underlying mechanisms. In silico gene perturbation and subsequent experiments confirm NFATc2 regulation of type I interferon response and neuroinflammation. Our analysis revealed that microglia, endothelial cells, and pericytes exhibited the highest activity of IFN-I. Furthermore, single-cell trajectory detection demonstrated that microglia in the midbrain of PD patients were in a pro-inflammatory activation state, which was validated in the 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model as well. We identified transcription factors NFATc2, which was significantly up-regulated and involved in the expression of ISGs and activation of microglia in PD. In the 1-Methyl-4-phenylpyridinium (MPP+)-induced BV2 cell model, the suppression of NFATc2 resulted in a reduction in IFN-ß levels, impeding the phosphorylation of STAT1, and attenuating the activation of the NF-κB pathway. Furthermore, the downregulation of NFATc2 mitigated the detrimental effects on SH-SY5Y cells co-cultured in conditioned medium. Our study highlights the critical role of microglia in type I interferon responses in PD. Additionally, we identified transcription factors NFATc2 as key regulators of aberrant type I interferon responses and microglial pro-inflammatory activation in PD. These findings provide new insights into the pathogenesis of PD and may have implications for the development of novel therapeutic strategies.


Assuntos
Interferon Tipo I , Neuroblastoma , Doença de Parkinson , Camundongos , Animais , Humanos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doenças Neuroinflamatórias , Células Endoteliais/metabolismo , NF-kappa B/metabolismo , Análise de Célula Única , Camundongos Endogâmicos C57BL
2.
Int J Prosthodont ; 0(0): 1-27, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477844

RESUMO

PURPOSE: The aim of this study was to determine and compare color differences of pressed lithium disilicate ceramic specimens after repeated firing cycles. An additional objective was to determine and evaluate correlation of CIEDE2000 values analyzed by X-Rite Color i5 Spectrophotometer, VITA EasyShade Advance 4.0 and Adobe Photoshop. MATERIAL AND METHODS: Tile specimens (N=36) with 8 x 10 x 1.5mm dimensions were prepared by IPS e.max Press lithium disilicate MT Monochromatic ingots and IPS e.max Multi Press lithium disilicate Multichromatic ingots. Specimens were exposed to 7 repeated firing cycles. Color analysis was performed after the 1st, 2nd, 3rd, 5th, and 7th firing cycles. CIE L*a*b* values were measured by X-Rite Color i5 Spectrophotometer, VITA EasyShade Advance 4.0 and Adobe Photoshop. CIE DE*2000 (ΔE*00) was calculated to estimate color differences. RESULTS: Linear regression and multiple comparison analysis (Tukey's HSD test) showed a statistically significant (p<.001) color difference ΔE*00 after multiple firing cycles. Statistically significant differences (p<.05) were also noted in different shade groups and between different instruments used for shade evaluation. Moreover, significant differences (p<.05) were found in interactive effects between different shades tested by different instrument, different shades tested after multiple firing cycles and different instruments after multiple firing cycles. CONCLUSIONS: Lithium disilicate material shows significant color differences after repeated firing cycles tested by three color analysis instruments. Measuring instruments used to evaluate CIE L*a*b* color values showed significant differences in color values analysis, which may lead to altered level of interpretation, particularly to determine perceptibility and clinical acceptability thresholds.

3.
J Prosthodont ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409924

RESUMO

PURPOSE: The objective was to determine the accuracy of 3D-printed dental models subjected to different storage conditions using six different material and printer combinations. MATERIALS AND METHODS: Three completely dentate models were designed using dental CAD software (3Shape Dental System). A horseshoe-shaped solid base with a posterior horizontal bar was used. The models were printed in a horizontal direction against the building platform without support. The models were printed using six printers with the corresponding recommended resin material: Carbon M2 (DPR10), HeyGears A2D4K (Model HP UV2.0), Stratasys J5 (MED610), Stratasys Origin One (DM200), Envision One (E-Model LightDLP), and Asiga Pro4K (VeriModel) with a standard layer thickness of 50 µm. All printed models underwent scanning using a laboratory scanner (Sirona inEOS X5) after printing. Subsequently, the models were randomly assigned into three groups of storage conditions, LT: cold environment (4 ± 1°C), HT: hot and dry environment (50 ± 2°C), and RT: room temperature (25 ± 2°C) serving as the control. Each group was kept under the designated condition and was scanned at 1, 2, 3, 4, and 8 weeks. The total number of models (N) was 72, with 6 printers producing 12 models per printer for 3 storage conditions, resulting in 4 models for each storage condition and each printer. The generated STL files were imported into a 3D inspection software for comparison with the original STL files. In-tolerance percentage, the deviation RMS, trueness, and precision were obtained and analyzed with least square mean linear regression using JMP Pro 15 to identify the significant effects (α = 0.05). RESULTS: The in-tolerance percentage as-printed was significantly different among different printers. Significant dimension deviations were observed after the first week of storage at HT and with subsequent weeks of storage. RT and LT did not show significant dimensional changes. Models printed with Carbon M2 showed the highest in-tolerance percentages compared to the other printers. CONCLUSIONS: The model deviations were affected by storage conditions and the printer used, with high-temperature storage showed least stability compared to low and room temperatures. No significant difference was observed between low and room temperature storage conditions. The Carbon M2 printer showed the highest accuracy among all printers tested. The region had a significant effect on the deviation measured, with the abutment body showing the least deviation. Among the 3D printers evaluated, A2D4K by HeyGears and Carbon M2 printers demonstrated the highest accuracy in terms of both precision and trueness.

4.
J Neuroinflammation ; 21(1): 13, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191407

RESUMO

Ferroptosis is an iron-dependent cell death mechanism involving the accumulation of lipid peroxides. As a critical regulator, glutathione peroxidase 4 (GPX4) has been demonstrated to be downregulated in epilepsy. However, the mechanism of ferroptosis in epilepsy remains unclear. In this study, bioinformatics analysis, analysis of epilepsy patient blood samples and cell and mouse experiments revealed strong associations among epilepsy, ferroptosis, microRNA-211-5p and purinergic receptor P2X 7 (P2RX7). P2RX7 is a nonselective ligand-gated homotrimeric cation channel, and its activation mainly increases neuronal activity during epileptic seizures. In our study, the upregulation of P2RX7 in epilepsy was attributed to the downregulation of microRNA (miR)-211-5p. Furthermore, P2RX7 has been found to regulate GPX4/HO-1 by alleviating lipid peroxidation induced by suppression of the MAPK/ERK signaling pathway in murine models. The dynamic decrease in miR-211-5p expression induces hypersynchronization and both nonconvulsive and convulsive seizures, and forebrain miR-211-5p suppression exacerbates long-lasting pentylenetetrazole-induced seizures. Additionally, in this study, induction of miR-211-5p expression or genetic-silencing of P2RX7 significantly reduced the seizure score and duration in murine models through the abovementioned pathways. These results suggest that the miR-211-5p/P2RX7 axis is a novel target for suppressing both ferroptosis and epilepsy.


Assuntos
Epilepsia , Ferroptose , MicroRNAs , Humanos , Animais , Camundongos , Epilepsia/genética , Estresse Oxidativo , Convulsões , MicroRNAs/genética , Receptores Purinérgicos P2X7/genética
5.
Sci Rep ; 13(1): 8648, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37244977

RESUMO

Bronchopulmonary dysplasia (BPD) is characterized by abnormal development of the blood vessels and alveoli in lungs, which largely occurs in premature infants. Exosomes (EXO) from very preterm infants (VPI) with BPD (BPD-EXO) impair angiogenic activities of human umbilical vein endothelial cells (HUVECs) via EXO-miRNAs cargo. This study aimed to determine whether and how BPD-EXO affect the development of BPD in a mouse model. We showed that treating BPD mice with BPD-EXO chronically and irreversibly aggravated lung injury. BPD-EXO up-regulated 139 and down-regulated 735 genes in the mouse lung tissue. These differentially expressed genes were enriched to the MAPK pathway (e.g., Fgf9 and Cacna2d3), which is critical to angiogenesis and vascular remodeling. BPD-EXO suppressed expression of Fgf9 and Cacna2d3 in HUVECs and inhibited migration, tube formation, and increased cell apoptosis in HUVECs. These data demonstrate that BPD-EXO aggravate lung injury in BPD mice and impair lung angiogenesis, plausibly leading to adverse outcomes of VPI with BPD. These data also suggest that BPD-EXO could serve as promising targets for predicting and treating BPD.


Assuntos
Displasia Broncopulmonar , Exossomos , Lesão Pulmonar , Humanos , Animais , Recém-Nascido , Camundongos , Displasia Broncopulmonar/genética , Recém-Nascido Prematuro , Lesão Pulmonar/etiologia , Lesão Pulmonar/metabolismo , Exossomos/metabolismo , Sangue Fetal , Pulmão , Células Endoteliais da Veia Umbilical Humana
6.
Pharmaceutics ; 15(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37111748

RESUMO

Bacterial vaginosis (BV) is an infection of the vagina associated with thriving anaerobes, such as Gardnerella vaginitis and other associated pathogens. These pathogens form a biofilm responsible for the recurrence of infection after antibiotic therapy. The aim of this study was to develop a novel mucoadhesive polyvinyl alcohol and polycaprolactone electrospun nanofibrous scaffolds for vaginal delivery, incorporating metronidazole, a tenside, and Lactobacilli. This approach to drug delivery sought to combine an antibiotic for bacterial clearance, a tenside biofilm disruptor, and a lactic acid producer to restore healthy vaginal flora and prevent the recurrence of bacterial vaginosis. F7 and F8 had the least ductility at 29.25% and 28.39%, respectively, and this could be attributed to the clustering of particles that prevented the mobility of the crazes. F2 had the highest at 93.83% due to the addition of a surfactant that increased the affinity of the components. The scaffolds exhibited mucoadhesion between 31.54 ± 0.83% and 57.86 ± 0.95%, where an increased sodium cocoamphoacetate concentration led to increased mucoadhesion. F6 showed the highest mucoadhesion at 57.86 ± 0.95%, as compared to 42.67 ± 1.22% and 50.89 ± 1.01% for the F8 and F7 scaffolds, respectively. The release of metronidazole via a non-Fickian diffusion-release mechanism indicated both swelling and diffusion. The anomalous transport within the drug-release profile pointed to a drug-discharge mechanism that combined both diffusion and erosion. The viability studies showed a growth of Lactobacilli fermentum in both the polymer blend and the nanofiber formulation that was retained post-storage at 25 °C for 30 days. The developed electrospun scaffolds for the intravaginal delivery of Lactobacilli spp., along with a tenside and metronidazole for the management of bacterial vaginosis, provide a novel tool for the treatment and management of recurrent vaginal infection.

7.
Crit Rev Food Sci Nutr ; : 1-25, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36999969

RESUMO

Microalgae have great potential as a future source to meet the increasing global demand for foods. Several microalgae are permitted as safety sources in different countries and regions, and processed as commercial products. However, edible safety, economic feasibility, and acceptable taste are the main challenges for microalgal application in the food industry. Overcome such challenges by developing technology accelerates transition of microalgae into sustainable and nutritious diets. In this review, edible safety of Spirulina, Chlamydomonas reinhardtii, Chlorella, Haematococcus pluvialis, Dunaliella salina, Schizochytrium and Nannochloropsis is introduced, and health benefits of microalgae-derived carotenoids, amino acids, and fatty acids are discussed. Technologies of adaptive laboratory evolution, kinetic model, bioreactor design and genetic engineering are proposed to improve the organoleptic traits and economic feasibility of microalgae. Then, current technologies of decoloration and de-fishy are summarized to provide options for processing. Novel technologies of extrusion cooking, delivery systems, and 3D bioprinting are suggested to improve food quality. The production costs, biomass values, and markets of microalgal products are analyzed to reveal the economic feasibility of microalgal production. Finally, challenges and future perspectives are proposed. Social acceptance is the major limitation of microalgae-derived foods, and further efforts are required toward the improvement of processing technology.

8.
Rev Sci Instrum ; 93(10): 104703, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319348

RESUMO

The development of pulsed power technology requires an electron beam accelerator with high output power and repetitive operation. A compact repetitive electron beam accelerator based on a pulse transformer and a pulse forming line of high permittivity liquid, as an essential type of one, has attracted extensive attention at the present time. In this paper, the development of a compact high energy-density electron beam accelerator, viz., HEART-20, based on a propylene carbonate (PC) forming line is presented. The accelerator HEART-20 consists of a primary energy source, a pulse transformer, a PC pulse forming line, a gas spark gap switch, and a vacuum diode. First, the operation principle of the accelerator is described. Second, the design of the accelerator's parameters is presented. A pulse transformer is developed for rapid charging of the PC-filled pulse forming line. The coupling coefficient is above 0.9, the voltage ratio is about 200, and the operation voltage is about 800 kV. Third, the energy storage characteristics of PC are investigated. The insulation characteristics of PC under positive charging voltage are found to perform better than those under negative charging voltage. The insulating strength of PC can be improved by pressurization. Finally, the development of the accelerator HEART-20 is presented. Across a vacuum diode load, it can steadily operate at a 20 GW output power in 5 Hz rep-rate. Moreover, it can drive a magnetically insulated line oscillator to produce about 2.0 GW microwave. These findings provide a good foundation for the development of a rep-rate intensive electron beam accelerator with promising applications for the future.

9.
Rev Sci Instrum ; 93(10): 104710, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319380

RESUMO

Relativistic magnetron (RM) is a promising high-power microwave source, whose advantages include high efficiency, high power, and compact configuration. Enhancing power efficiency and output power are the most important two development directions for RM. Based on the two targets, a high efficiency and high power RM is presented and investigated numerically and experimentally in this paper. When the diode voltage is 485 kV, the beam current is 6.9 kA, and the magnetic field is 0.34 T, and high power microwave is generated with the power of 1.35 GW, frequency of 1.47 GHz, and power efficiency of 40.3% in the experiments.

10.
Cell Mol Biol (Noisy-le-grand) ; 68(4): 75-85, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35988287

RESUMO

Nasopharyngeal carcinoma (NPC) is one of the most lethal head and neck cancers, threatening the health of people across the globe, especially in East and Southeast Asia, the Arctic, the Middle East and North Africa. Long non-coding RNAs (lncRNA) have been reported to regulate multiple cancers, including NPC. However, the role of LINC01140 in NPC remains to be covered. In this study, we found that LINC01140 is downregulated in NPC cells. It was uncovered from functional assays that LINC01140 inhibits the proliferation and improves the apoptosis and radiosensitivity of NPC cells. The downstream mechanism by which LINC01140 exerted its functions was explored in subsequent. As proven by mechanism experiments, cytoplasmic LINC01140 positively regulated the expression of ZNF621 through competitively binding to miR-452-5p. ZNF621 can also enhance the radiosensitivity of NPC cells. To summarize, LINC01140 regulates the radiosensitivity of NPC cells through the competing endogenous RNA (ceRNA) mode. Our study aims to identify novel biomarkers for regulating the radiosensitivity of NPC.


Assuntos
MicroRNAs , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Tolerância a Radiação , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Tolerância a Radiação/genética , Dedos de Zinco/genética , Dedos de Zinco/fisiologia
11.
Int Dent J ; 72(6): 859-865, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36031428

RESUMO

OBJECTIVE: The aim of this research was to assess the efficiency of 4 restorative glass ionomer cements (GICs): Fuji IX (GC), ChemFil Rock (DENSPLY), Riva Self-Cure (SDI), and Ketac Nano (3M ESPE). MATERIALS AND METHODS: The 4 restorative glass ionomers' diametral tensile and compressive strengths were evaluated at room temperature for 24 hours and then stored in distilled water. The universal testing machine (INSTRON 5566A) was used to record the maximum load necessary to fracture specimens. Surface wear, diametral tensile strength, and compressive strength against dental ceramic were compared using analysis of variance followed by the Bonferroni method at a significance level of 0.05. RESULTS: Ketac Nano and ChemFil Rock were found to have better diametral tensile strength than Riva Self-Cure and Fuji IX. The significant difference between ChemFil Rock and Fuji IX (P ≤ .005) and ChemFil Rock with Riva Self-Cure (P ≤ .005) was shown by post hoc analysis. Ketac Nano had better tensile strength than Riva Self-Cure and Fuji IX. Fuji IX showed the lowest material loss of the GICs as revealed by wear against VITABLOCS Mark II (VITA Zahnfabrik). CONCLUSIONS: This study indicated a significant difference in the compressive strengths of ChemFil Rock and Riva Self-Cure. ChemFil Rock had the highest tensile strength. The diameter tensile strength of all 4 materials was statistically insignificant. Finally, Fuji IX had the least amount of material loss. ChemFil Rock was proven to be more effective than Fuji IX.


Assuntos
Resinas Acrílicas , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais
12.
Animals (Basel) ; 12(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35158586

RESUMO

Species conservation actions are guided by available information on the biogeography of the protected species. In this study, we integrated the occurrence data of Siberian musk deer (Moschus moschiferus L.) collected from 2019 to 2021 with species distribution models to estimate the species' potential distribution in Northeast China. We then identified conservation priority areas using a core-area zonation algorithm. In addition, we analyzed core patch fragmentation using FRAGSTATS. Lastly, we identified potential connectivity corridors and constructed a potential protection network based on the least-cost path and the circuit theory. The results showed concentrations of M. moschiferus in the northern Greater Khingan Mountains, the southeastern Lesser Khingan Mountains, and the eastern Changbai Mountains, with a potential distribution area of 127,442.14 km2. Conservation priority areas included 41 core patches with an area of 106,306.43 km2. Patch fragmentation mainly occurred in the Changbai Mountains and the Lesser Khingan Mountains. We constructed an ecological network composed of 41 core patches and 69 linkages for M. moschiferus in Northeast China. The results suggest that the Greater Khingan Mountains represent the most suitable area to maintain the stability of M. moschiferus populations in Northeast China. Considering the high habitat quality requirements of M. moschiferus and its endangered status, we propose that the Chinese government accelerates the construction of the Greater Khingan Mountains National Park and the Lesser Khingan Mountains National Park and enlarges the Northeast China Tiger and Leopard National Park to address the fragmentation of protected areas and the habitat of M. moschiferus.

13.
Chemosphere ; 291(Pt 3): 133053, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34861255

RESUMO

Phosphorus is a nutrient that is essential to nature and human life and has attracted attention because of its very limited reserves. Dwindling phosphorus reserves and soaring prices have made the recovery of phosphorus from waste biosolids even more urgent. Waste activated sludge, as the final destination of most of the phosphorus in human domestic and industrial water, has been considered as a reliable source of phosphorus recovery. The thermal treatment method of sewage sludge is currently a relatively environmentally friendly disposal method, which mainly includes incineration, pyrolysis and hydrothermal carbonization. This paper reviews the methods for the recovery of different forms of phosphorus (wet chemical, thermochemical and electrodialysis) from solid products obtained from different sludge thermal treatment methods (incinerated sewage sludge ash, pyrolysis of sewage sludge char and hydrochar) and the bioavailability of the recovered phosphorus products. Incineration of sewage sludge is currently the most established and effective method for recovering phosphorus from the thermal treatment products of sewage sludge. One of the wet chemical methods has been applied on a commercial scale and is expected to be further developed for future industrial applications. Pyrolysis and hydrothermal carbonation still have many research gaps in this field. Based on their principles and laboratory performance, both of them have the potential to recover phosphorus and should be further explored.


Assuntos
Fósforo , Esgotos , Disponibilidade Biológica , Humanos , Incineração , Pirólise
14.
Chemosphere ; 288(Pt 2): 132549, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34653483

RESUMO

Without extra adjustment of pH, the effects of cupric ions (Cu(II)) and hydrogen peroxide (H2O2) alone or in combination on sludge dewatering were studied. It showed good dewatering capability after treated by Cu(II) and Cu(II)/H2O2, which indicated by the capillary suction times (CST) decreased from 120.8 ± 4.7 s (control) to about 40 s, and the water content (Wc) of sludge cake dropped by about 10%. The results showed that the extracellular polymeric substances (EPS) were destroyed, which characterized by a significant decrease in the biopolymers' concentrations in tightly-bound EPS. Meanwhile, more rough and porous microstructures and higher zeta potentials were obtained after conditioned. Based on the changes of physicochemical properties of sludge, the variations of EPS, and the identification of reactive species, two distinct mechanisms of improved sludge dewatering were postulated. As for Cu(II) treatment, it was mainly due to the surface charge neutralization, strong cytotoxicity of Cu(I) produced by intracellular reduction of Cu(II), and pH decline caused by Cu(II) hydrolysis that improved sludge dewatering performance, which could be noted as a "non-radical pathway". When in combination with H2O2, hydroxyl radicals (·OH) produced by Cu(II)-catalyzed Fenton-like process played a dominant role in degrading sludge flocs and EPS, which could be regarded as a "radical pathway".


Assuntos
Peróxido de Hidrogênio , Esgotos
15.
Rev Sci Instrum ; 92(10): 104708, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34717381

RESUMO

This study investigates the frequency tunability of a coaxial transverse electromagnetic mode (TEM)-linear-polarized TE11 mode tunable turnstile mode converter (TTMC) for high-power microwave applications using a combination of simulation and experiment. In the proposed structure, the sliding folded waveguide can be moved radially to meet the requirement of linear polarization, and the matching structure is designed to eliminate the undesired reflection. The simulation shows that the conversion efficiency of the TTMC can reach over 99% in the frequency range of 1.45-2.35 GHz, corresponding to a frequency tuning bandwidth of about 47.4%. Moreover, the TTMC can maintain a continuous high conversion efficiency at different frequency points by changing the tuning mechanism. The experimental investigation shows that the TTMC can convert the coaxial TEM mode into a circular waveguide TE11 mode with a conversion efficiency of above 95% in the frequency range of 1.55-2.35 GHz. The experimental measurements agree well with the simulation results, implying feasibility of the TTMC design and its superior performance.

16.
Bioresour Technol ; 337: 125406, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34147773

RESUMO

This study comprehensively explored underlying mechanism of fed-batch culture on product biosynthesis in Chromochloris zofingiensis by dynamic model, targeted metabolite determination, enzyme activity analysis, and 13C tracer-based metabolic flux analysis. Based on dynamic models of cell growth and product formation, exponential fed-batch culture and fed-batch culture based on pH changes were established to increase biomass concentration by 20.05-fold and 18.28-fold, respectively. Exponential fed-batch culture exhibited great potentials in biodiesel and protein productions from microalgae. Systematic metabolic tools revealed fed-batch culture limited photosynthetic efficiency by inhibiting photosystem and Rubisco activity, while strengthened respiratory action to provide more substances and energy for product biosynthesis. Fed-batch culture elevated biosynthetic capability for carotenoid and lipid by promoting related metabolic flux and contents of pyruvate and ace-CoA. Finally, economic analysis revealed biomass cost was decreased to 1.99 $/kg from 2.39 $/kg, suggesting fed-batch culture was a cost-effective strategy to improve economic viability of microalgal production.


Assuntos
Clorofíceas , Microalgas , Técnicas de Cultura Celular por Lotes , Biocombustíveis , Biomassa
18.
Mar Drugs ; 20(1)2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35049885

RESUMO

Adaptive laboratory evolution (ALE) has been widely utilized as a tool for developing new biological and phenotypic functions to explore strain improvement for microalgal production. Specifically, ALE has been utilized to evolve strains to better adapt to defined conditions. It has become a new solution to improve the performance of strains in microalgae biotechnology. This review mainly summarizes the key results from recent microalgal ALE studies in industrial production. ALE designed for improving cell growth rate, product yield, environmental tolerance and wastewater treatment is discussed to exploit microalgae in various applications. Further development of ALE is proposed, to provide theoretical support for producing the high value-added products from microalgal production.


Assuntos
Microalgas/crescimento & desenvolvimento , Animais , Aquicultura , Organismos Aquáticos , Biotecnologia
19.
Front Aging Neurosci ; 13: 762649, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35250531

RESUMO

BACKGROUND AND OBJECTIVE: Inflammatory mediators are closely associated with the pathogenesis of Alzheimer's disease (AD) and mild cognitive impairment (MCI). Netrin-1 is an axon guidance protein and despite its capacity to function as a neuroimmune guidance signal, its role in AD or MCI is poorly understood. In addition, the association among netrin-1, cognitive impairment and serum inflammatory cytokines such as interleukin-17 (IL-17) and tumor necrosis (TNF-α) remains unclear. The aim of this study was to determine serum levels of IL-17, TNF-α and netrin-1in a cohort of AD and MCI patients, and to study the relationship between these cytokines and cognitive status, as well as to assess the possible relationships between netrin-1 levels and inflammatory molecules. METHODS: Serum concentrations of netrin-1, TNF-α and IL-17 were determined in 20 AD patients, 22 MCI patients and 22 healthy controls using an enzyme-linked immunosorbent assay (ELISA). In addition, neuropsychological evaluations and psychometric assessments were performed in all subjects. RESULTS: Serum netrin-1 levels were decreased in AD and MCI patients and were positively correlated with Mini Mental State Examination (MMSE) scores. In contrast, serum TNF-α and IL-17 levels were elevated in AD and MCI cohorts and negatively correlated with MMSE scores. Serum netrin-1 levels were inversely related with TNF-α and IL-17 levels in AD, but not MCI, patients. CONCLUSION: Based on the findings reported here, netrin-1 may serve as a marker for the early recognition of dementia and predict cognitive impairment.

20.
Gynecol Oncol ; 159(2): 527-533, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32977988

RESUMO

OBJECTIVE: Measure the size and shape of talc particles in talcum powder and compare this data to the size and shape of talc particles found in surgically resected tissues from patients with ovarian carcinoma. METHODS: Using polarized light microscopy (PLM) and scanning electron microscopy (SEM), we measured the size and shape of talc particles in samples of talc-containing baby powder (TCBP) and surgically resected pelvic tissues (hysterectomies) from talc-exposed patients with ovarian carcinoma. RESULTS: The most frequent class of particles in TCBP can be unequivocally identified as talc, using both polarized light microscopy and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDX). The talc particles found in resected tissues from ovarian carcinoma patients are similar in size and shape to the most abundant morphological class of particles in TCBP. CONCLUSIONS: This finding, combined with previous epidemiological literature and tissue-based analytical studies, provides further evidence that the small, isodiametric particles that dominate TCBP can migrate from the perineum and become lodged in distal structures in the female reproductive tract, where they may lead to an increased risk of developing ovarian carcinoma.


Assuntos
Linfonodos/química , Omento/química , Ovário/química , Talco/análise , Adulto , Idoso , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Linfonodos/ultraestrutura , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Omento/ultraestrutura , Neoplasias Ovarianas/patologia , Ovário/ultraestrutura , Talco/efeitos adversos , Talco/farmacocinética
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