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1.
Abdom Radiol (NY) ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704783

RESUMEN

OBJECTIVE: To compare radiomics and non-radiomics in predicting early recurrence (ER) in patients with hepatocellular carcinoma (HCC) after curative surgery. METHODS: We systematically searched PubMed and Embase databases. Studies with clear reference criteria were selected. Data were extracted and assessed for quality using the quality in prognosis studies tool (QUIPS) by two independent authors. All included radiomics studies underwent radiomics quality score (RQS) assessment. We calculated sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using random or fixed models with a 95%CI. Forest maps visualized the data, and summary receiver operating characteristic (sROC) curves with the area under the curve (AUC) were generated. Meta-regression and subgroup analyses explored sources of heterogeneity. We compared sensitivity, specificity, PLR, and NLR using the z-test and compared AUC values using the Delong test. RESULTS: Our meta-analysis included 10 studies comprising 1857 patients. For radiomics, the pooled sensitivity, specificity, AUC of sROC, PLR and NLR were 0.84(95%CI: 0.78-0.89), 0.80(95%CI: 0.75-0.85), 0.89(95%CI: 0.86-0.91), 4.28(95%CI: 3.48-5.27) and 0.20(95%CI: 0.14-0.27), respectively, but with significant heterogeneity (I2 = 60.78% for sensitivity, I2 = 55.79% for specificity) and potential publication bias (P = 0.04). The pooled sensitivity, specificity, AUC of sROC, PLR, NLR for non-radiomics were 0.75(95%CI:0.68-0.81), 0.78(95%CI:0.72-0.83), 0.83(95%CI: 0.80-0.86), 3.45(95%CI: 2.68-4.44) and 0.32(95%CI: 0.24-0.41), respectively. There was no significant heterogeneity in this group (I2 = 0% for sensitivity, I2 = 17.27% for specificity). Radiomics showed higher diagnostic accuracy (AUC: 0.89 vs. 0.83, P = 0.0456), higher sensitivity (0.84 vs. 0.75, P = 0.0385) and lower NLR (0.20 vs. 0.32, P = 0.0287). CONCLUSION: The radiomics from preoperative MRI effectively predicts ER of HCC and has higher diagnostic accuracy than non-radiomics. Due to potential publication bias and suboptimal RQS scores in radiomics, these results should be interpreted cautiously.

2.
Acad Radiol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38664142

RESUMEN

RATIONALE AND OBJECTIVES: Microvascular invasion (MVI) is a key prognostic factor for hepatocellular carcinoma (HCC). The predictive models for solitary HCC could potentially integrate more comprehensive tumor information. Owing to the diverse findings across studies, we aimed to compare radiomic and non-radiomic methods for preoperative MVI detection in solitary HCC. MATERIALS AND METHODS: Articles were reviewed from databases including PubMed, Embase, Web of Science, and the Cochrane Library until April 7, 2023. The pooled sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated using a random-effects model within a 95% confidence interval (CI). Diagnostic accuracy was assessed using summary receiver-operating characteristic curves and the area under the curve (AUC). Meta-regression and Z-tests identified heterogeneity and compared the predictive accuracy. Subgroup analyses were performed to compare the AUC of two methods according to study type, study design, tumor size, modeling methods, and imaging modality. RESULTS: The analysis incorporated 26 studies involving 3539 patients with solitary HCC. The radiomics models showed a pooled sensitivity and specificity of 0.79 (95%CI: 0.72-0.85) and 0.78 (95%CI: 0.73-0.82), with an AUC at 0.85 (95%CI: 0.82-0.88). Conversely, the non-radiomics models had sensitivity and specificity of 0.74 (95%CI: 0.65-0.81) and 0.88 (95%CI: 0.82-0.92) and an AUC of 0.88 (95%CI: 0.85-0.91). Subgroups with preoperative MRI, larger tumors, and functional imaging had higher accuracy than those using preoperative CT, smaller tumors, and conventional imaging. CONCLUSION: Non-radiomic methods outperformed radiomic methods, but high heterogeneity calls across studies for cautious interpretation.

3.
Opt Express ; 32(6): 9837-9846, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571208

RESUMEN

Obstruction is inevitable and will significantly impact the actual output performance of photovoltaic modules, even jeopardize their operational safety. We introduced a layer of bubbles into photovoltaic glass. These bubbles can alter the path of incident light, while the internal reflection at the glass/air interface enables the redirected light rays to have longer lateral propagation distance, circumventing the obstructions. The optimized photovoltaic glass with a bubble diameter of 1.8 mm and a surface density of 16 cm-2 enables the light intensity underneath a 6.6 × 6.6 cm2 obstruction to reach 21.83% of the incident light intensity. This enhancement permits a partial shading of the photovoltaic module, increasing its output power by ∼20.8% and decreasing the reverse bias voltage on the shaded cell by ∼1.4 V.

4.
Biotechnol Adv ; 73: 108354, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38588906

RESUMEN

Thraustochytrids are marine microorganisms known for their fast growth and ability to store lipids, making them useful for producing polyunsaturated fatty acids (PUFAs), biodiesel, squalene, and carotenoids. However, the high cost of production, mainly due to expensive fermentation components, limits their wider use. A significant challenge in this context is the need to balance production costs with the value of the end products. This review focuses on integrating the efficient utilization of waste with Thraustochytrids fermentation, including the economic substitution of carbon sources, nitrogen sources, and fermentation water. This approach aligns with the 3Rs principles (reduction, recycling, and reuse). Furthermore, it emphasizes the role of Thraustochytrids in converting waste into lipid chemicals and promoting sustainable circular production models. The aim of this review is to emphasize the value of Thraustochytrids in converting waste into treasure, providing precise cost reduction strategies for future commercial production.


Asunto(s)
Fermentación , Biocombustibles , Lípidos/biosíntesis , Lípidos/química , Estramenopilos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Biotecnología/economía , Biotecnología/métodos , Carbono/metabolismo
5.
CNS Neurosci Ther ; 29(12): 3925-3934, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37381696

RESUMEN

AIMS: Status epilepticus (SE) is the most common neurological emergency in pediatric patients. This study aimed to screen for prognostic biomarkers of SE in the cerebrospinal fluid (CSF) using metabolomics. METHODS: Ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS) was conducted to identify prognostic biomarkers in CSF metabolomics by comparing the poor outcome group (N = 13) with the good outcome group (N = 15) of children with SE. Differentially expressed metabolites were identified using Mann-Whitney U test corrected by Benjamini-Hochberg and partial least squares discriminant analysis (PLS-DA). RESULTS: The PLS-DA model identified and validated significant metabolic differences between the poor and good outcome groups of children with SE (PLS-DA with R2 Y = 0.992 and Q2 = 0.798). A total of 49 prognosis-related metabolites were identified. Of these metabolites, 20 including glutamyl-glutamine, 3-iodothyronamine, and L-fucose had an area under the curve (AUC) ≥ 80% in prognostic prediction of SE. The logistic regression model combining glutamyl-glutamine and 3-iodothyronamine produced an AUC value of 0.976, with a sensitivity of 0.863 and specificity of 0.956. Pathway analysis revealed that dysregulation of the citrate cycle (TCA) and arginine biosynthesis may contribute to poor SE prognosis. CONCLUSIONS: This study highlighted the prognosis-related metabolomic disturbances in the CSF of children with SE and identified potential prognostic biomarkers. A prognostic prediction model combining glutamyl-glutamine and 3-iodothyronamine with high predictive value was established.


Asunto(s)
Glutamina , Metabolómica , Humanos , Niño , Pronóstico , Metabolómica/métodos , Metaboloma , Biomarcadores , Cromatografía Líquida de Alta Presión
6.
Front Microbiol ; 14: 1141378, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36998392

RESUMEN

Deoxynivalenol (DON) is a mycotoxin that contaminates animal feed and crops around the world. DON not only causes significant economic losses, but can also lead diarrhea, vomiting, and gastroenteritis in humans and farm animals. Thus, there is an urgent need to find efficient approaches for DON decontamination in feed and food. However, physical and chemical treatment of DON may affect the nutrients, safety, and palatability of food. By contrast, biological detoxification methods based on microbial strains or enzymes have the advantages of high specificity, efficiency, and no secondary pollution. In this review, we comprehensively summarize the recently developed strategies for DON detoxification and classify their mechanisms. In addition, we identify remaining challenges in DON biodegradation and suggest research directions to address them. In the future, an in-depth understanding of the specific mechanisms through which DON is detoxified will provide an efficient, safe, and economical means for the removal of toxins from food and feed.

7.
Nature ; 616(7955): 176-182, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36991118

RESUMEN

Repression of gene expression by protein complexes of the Polycomb group is a fundamental mechanism that governs embryonic development and cell-type specification1-3. The Polycomb repressive deubiquitinase (PR-DUB) complex removes the ubiquitin moiety from monoubiquitinated histone H2A K119 (H2AK119ub1) on the nucleosome4, counteracting the ubiquitin E3 ligase activity of Polycomb repressive complex 1 (PRC1)5 to facilitate the correct silencing of genes by Polycomb proteins and safeguard active genes from inadvertent silencing by PRC1 (refs. 6-9). The intricate biological function of PR-DUB requires accurate targeting of H2AK119ub1, but PR-DUB can deubiquitinate monoubiquitinated free histones and peptide substrates indiscriminately; the basis for its exquisite nucleosome-dependent substrate specificity therefore remains unclear. Here we report the cryo-electron microscopy structure of human PR-DUB, composed of BAP1 and ASXL1, in complex with the chromatosome. We find that ASXL1 directs the binding of the positively charged C-terminal extension of BAP1 to nucleosomal DNA and histones H3-H4 near the dyad, an addition to its role in forming the ubiquitin-binding cleft. Furthermore, a conserved loop segment of the catalytic domain of BAP1 is situated near the H2A-H2B acidic patch. This distinct nucleosome-binding mode displaces the C-terminal tail of H2A from the nucleosome surface, and endows PR-DUB with the specificity for H2AK119ub1.


Asunto(s)
Enzimas Desubicuitinizantes , Histonas , Complejo Represivo Polycomb 1 , Proteínas del Grupo Polycomb , Humanos , Microscopía por Crioelectrón , Histonas/química , Histonas/metabolismo , Nucleosomas/química , Nucleosomas/genética , Nucleosomas/metabolismo , Complejo Represivo Polycomb 1/química , Complejo Represivo Polycomb 1/metabolismo , Complejo Represivo Polycomb 1/ultraestructura , Proteínas del Grupo Polycomb/química , Proteínas del Grupo Polycomb/metabolismo , Proteínas del Grupo Polycomb/ultraestructura , Ubiquitina/metabolismo , Ubiquitina Tiolesterasa/química , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina Tiolesterasa/ultraestructura , Ubiquitinación , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Proteínas Represoras/ultraestructura , Dominio Catalítico , Enzimas Desubicuitinizantes/clasificación , Enzimas Desubicuitinizantes/metabolismo , Enzimas Desubicuitinizantes/ultraestructura , Especificidad por Sustrato , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/ultraestructura
8.
ACS Appl Mater Interfaces ; 15(9): 11875-11884, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36808943

RESUMEN

A photorechargeable device can generate power from sunlight and store it in one device, which has a broad application prospect in the future. However, if the working state of the photovoltaic part in the photorechargeable device deviates from the maximum power point, its actual power conversion efficiency will reduce. The strategy of voltage match on the maximum power point is reported to achieve a high overall efficiency (ηoa) of the photorechargeable device assembled by a passivated emitter and rear cell (PERC) solar cell and Ni-based asymmetric capacitors. According to matching the voltage of the maximum power point of the photovoltaic part, the charging characteristics of the energy storage part are adjusted to realize a high actual power conversion efficiency of the photovoltaic part (ηpv). The ηpv of a Ni(OH)2-rGO-based photorechargeable device is 21.53%, and the ηoa is up to 14.55%. This strategy can promote further practical application for the development of photorechargeable devices.

9.
Nanotechnology ; 34(20)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36796094

RESUMEN

Metal-organic frameworks (MOFs), as a class of promising material with adjustable function and controllable structure, have been widely used in the food industry, chemical industry, biological medicine, and sensors. Biomacromolecules and living systems play a critical role in the world. However, the insufficiency in stability, recyclability, and efficiency, significantly impedes their further utilization in slightly harsh conditions. MOF-bio-interface engineering effectively address the above-mentioned shortages of biomacromolecules and living systems, and thereby attracting considerable attentions. Herein, we systematically review the achievements in the area of MOF-bio-interface. In particular, we summarize the interface between MOFs and proteins (enzymes and non-enzymatic proteins), polysaccharides, DNA, cells, microbes, and viruses. Meanwhile, we discuss the limitations of this approach and propose future research directions. We expect that this review could provide new insights and inspire new research efforts towards life science and material science.


Asunto(s)
Estructuras Metalorgánicas
10.
J Hazard Mater ; 443(Pt B): 130331, 2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36444056

RESUMEN

B-doped graphene, as an efficient and environmental-friendly metal-free catalyst, has aroused much attention in the electrochemical advanced oxidation process (EAOP), but the bottleneck in this field is to determine the relationship between the surface structure regulation and activity of catalysts. Herein, the B-doped graphene aerogel (BGA) fabricated gas diffusion electrode was prepared and used as a cathode for EAOP to remove tetracycline (TC). Higher free radical yield (169.59 µM), faster reaction speed (0.35 min-1) and higher TC removal rate (99.93%) were found in the BGA system. Molecular dynamics simulation unveiled the interaction energy of BGA was greater than the raw graphene aerogel (GA). The adsorption-activation process of H2O2 and the degradation process of TC occurred in the first adsorption layer of catalysts. And both processes turned more orderly after B doping, which accelerated the reaction efficiency. Results of density functional theory displayed the contribution of three B-doped structures to improve the binding strength between H2O2 and BGA was: - BCO2 (-0.23 eV) > - BC2O (-0.16 eV) > - BC3 (-0.09 eV). -BCO2 was inferred to be the main functional region of H2O2 in-situ activation to hydroxyl radical (•OH), while -BC2O and -BC3 were responsible for improving H2O2 production.

11.
Appl Biochem Biotechnol ; 195(2): 1574-1588, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36346559

RESUMEN

Solar-driven biocatalysis technologies can combine inorganic photocatalytic materials with biological catalysts to convert CO2, light, and water into chemicals, offering the promise of high energy efficiency and a broader product scope than that of natural photosynthesis. Solar energy is the most abundant renewable energy source on earth, but it cannot be directly utilized by current industrial microorganisms. Therefore, the establishment of a solar-driven bio-catalysis platform, a bridge between solar energy and heterotrophic microorganisms, can dramatically increase carbon flux in biomanufacturing systems and consequently may revolutionize the biorefinery. This review first discusses the main applications of microbe-photocatalyst hybrid (MPH) systems in biorefinery processes. Then, various strategies to improve the electron transfer by microorganisms at the inorganic photocatalytic material interface are discussed, especially biohybrid systems based on autotrophic or heterotrophic bacteria and photocatalytic materials. Finally, we discuss the current challenges and offer potential solutions for the development of MPH systems.


Asunto(s)
Fotosíntesis , Energía Solar , Energía Renovable , Agua/química , Transporte de Electrón
12.
J Safety Res ; 83: 119-127, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36481003

RESUMEN

INTRODUCTION: This study examined the impact of daylight saving time changes on traffic crashes in the United States. Using a data-driven regression analysis approach, the study analyzed 2014-2016 crash data from six states spanning all four major time zones in the contiguous United States. METHOD: The researchers developed regression models for a number of analysis scenarios and by days of week separately. Based on the crash data, the team used an eight-week impact period for the spring time change and a four-week impact period for the fall time change. RESULTS: The regression analysis showed that the spring time change was followed by an overall crash reduction of 18% during the eight-week period immediately after the time change, with a considerably higher crash reduction for freeway crashes (24%), rural crashes (24%), or non-intersection crashes (21%). The time change back to SDT in fall was followed by a 6% overall crash increase during the following four weeks, with considerably higher increases for freeway crashes (15%), non-intersection crashes (9%), nighttime crashes (28%), single-vehicle crashes (28%), and crashes in urban areas (12%). This study provides additional insights, including in many cases more comprehensive knowledge on how the changes to and from DST each year affect roadway traffic crashes. PRACTICAL APPLICATIONS: The findings of this project further add to the current understanding on how the time changes affect public health in the form of traffic crashes. They also serve as additional evidence for public policy makers to better weigh the benefits and impacts associated with the time changes in the United States for relevant policy makings.


Asunto(s)
Política Pública , Humanos
13.
Biotechnol Biofuels Bioprod ; 15(1): 151, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36581946

RESUMEN

BACKGROUND: As an attractive platform chemical, malic acid has been commonly used in the food, feed and pharmaceutical field. Microbial fermentation of biobased sources to produce malic acid has attracted great attention because it is sustainable and environment-friendly. However, most studies mainly focus on improving yield and ignore shortening fermentation time. A long fermentation period means high cost, and hinders the industrial applications of microbial fermentation. Stresses, especially oxidative stress generated during fermentation, inhibit microbial growth and production, and prolong fermentation period. Previous studies have shown that polypeptides could effectively relieve stresses, but the underlying mechanisms were poorly understood. RESULTS: In this study, polypeptides (especially elastin peptide) addition improves the productivity of malic acid in A. niger, resulting in shortening of fermentation time from 120 to 108 h. Transcriptome and biochemical analyses demonstrated that both antioxidant enzyme-mediated oxidative stress defense system, such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and nonenzymatic antioxidant system, such as glutathione, were enhanced in the presence of elastin peptide, suggesting elastin peptide relieving oxidative stresses is involved in many pathways. In order to further investigate the relationship between oxidative stress defense and malic acid productivity, we overexpressed three enzymes (Sod1, CAT, Tps1) related to oxidation resistance in A. niger, respectively, and these resulting strains display varying degree of improvement in malic acid productivity. Especially, the strain overexpressing the Sod1 gene achieved a malate titer of 91.85 ± 2.58 g/L in 96 h, corresponding to a productivity of 0.96 g/L/h, which performs better than elastin peptide addition. CONCLUSIONS: Our investigation provides an excellent reference for alleviating the stress of the fungal fermentation process and improving fermentation efficiency.

14.
Phys Chem Chem Phys ; 24(46): 28429-28435, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36398884

RESUMEN

Subhani et al. found that Sm-doping in CsPbIBr2 decreased its bandgap from 2.05 eV to 1.8 eV; thus, the efficiency of CsPbIBr2 solar cells was improved by ∼30%. However, Sm is a vital strategic resource with high costs. Metal Sn is much more abundant and cheaper than Sm; meanwhile, it has been proven that Sn can adjust the bandgap of CsPbIBr2 in a broader range, 2.05 eV to 1.64 eV. Therefore, Sn-doping in CsPbIBr2 may improve the efficiency of CsPbIBr2 solar cells, even to a greater extent. In this work, we established the TiO2/CsPbIBr2 interface model by gradient Sn-doping in CsPbIBr2 and investigated the impacts of such gradient doping on the carrier separation behaviors at the TiO2/CsPbIBr2 interface from the aspects of the cross-interface electric field, bandgap, and band matching, based on first-principles calculations. It is found that gradient Sn-doping can transfer more electrons from TiO2 to perovskites, thus creating an enhanced cross-interface electric field conducive to the separation of carriers at the TiO2/CsPbIBr2 interface. Affected by the existence of the interface, the bandgap of each perovskite layer gradually increases as it moves away from the interface; in addition, due to the gradient Sn-doping, the steps between the bandgaps of adjacent perovskite layers become smaller and more uniform, which is favorable for the separation of electrons. In summary, gradient Sn-doping can improve the carrier separation at the TiO2/CsPbIBr2 interface.

15.
Appl Microbiol Biotechnol ; 106(24): 7973-7992, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36370160

RESUMEN

Over the last few decades, increasing concerns regarding fossil fuel depletion and excessive CO2 emissions have led to extensive fundamental studies and industrial trials regarding microbial chemical production. As an additive or precursor, L-malic acid has been shown to exhibit distinctive properties in the food, pharmaceutical, and daily chemical industries. L-malic acid is currently mainly fabricated through a fumarate hydratase-based biocatalytic conversion route, wherein petroleum-derived fumaric acid serves as a substrate. In this review, for the first time, we comprehensively describe the methods of malic acid strain transformation, raw material utilization, malic acid separation, etc., especially recent progress and remaining challenges for industrial applications. First, we summarize the various pathways involved in L-malic acid biosynthesis using different microorganisms. We also discuss several strain engineering strategies for improving the titer, yield, and productivity of L-malic acid. We illustrate the currently available alternatives for reducing production costs and the existing strategies for optimizing the fermentation process. Finally, we summarize the present challenges and future perspectives regarding the development of microbial L-malic acid production. KEY POINTS: • A range of wild-type, mutant, laboratory-evolved, and metabolically engineered strains which could produce L-malic acid were comprehensively described. • Alternative raw materials for reducing production costs and the existing strategies for optimizing the fermentation were sufficiently summarized. • The present challenges and future perspectives regarding the development of microbial L-malic acid production were elaboratively discussed.

16.
Int J Food Microbiol ; 379: 109869, 2022 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-35963080

RESUMEN

Pickles are typical traditional Chinese fermented vegetables. Complex microbiota interacts throughout the fermentation and deterioration process. Minimal studies are available involving quorum sensing (QS) signaling in pickles. This study investigated the changes in the general pickle properties and microbial diversity at 4 d, 31 d, and 79 d. The QS signaling activity of various strains isolated at these key time points was screened using biosensor strains, while the types of signal molecules were further identified using UHPLC/QTOF-MS/MS. At 4 d, Lactobacillus represented the dominant genus, while Lactobacillus plantarum was identified as the bacteria with AI-2-producing ability. At 31 d, the dominant genus was also Lactobacillus, while the relative abundance of Pediococcus displayed a distinct increase. At this time point, L. plantarum represented the AI-2-producing bacteria, followed by Lactobacillus brevis, Pediococcus sp., Enterobacter sp., and Bacillus megaterium. At 79 d, Lactobacillus was displaced by Enterobacter as the dominant microorganisms, while the AI-2-producing bacteria were identified as L. plantarum, Enterobacter sp., B. megaterium, Klebsiella sp., and Staphylococcus sp. Moreover, AHL activity was only present in isolates from the 79-d brine and was identified as C4-HSL and C6-HSL. In addition, the luxS gene was amplified via cDNA reversely transcription from the total RNA extracted from the brine at all three time points using the L. plantarum luxS primers. The AHL-related genes were only amplified in the RNA of 79-d brine samples using Klebsiella pneumoniae- and Bacillus cereus-related primers. This study presented theoretical references for QS during pickle fermentation and deterioration.


Asunto(s)
Alimentos Fermentados , Percepción de Quorum , Bacterias , Fermentación , ARN , Espectrometría de Masas en Tándem
17.
Biotechnol Bioeng ; 119(9): 2471-2481, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35665482

RESUMEN

Filamentous fungi occupy a uniquely favorable position in the bioproduction of organic acids. Intracellular stress is the main stimulator in filamentous fungi to produce and accumulate organic acids with high flux. However, stress can affect the physiological activities of filamentous fungi, thereby deteriorating their fermentation performance. Herein, we report that peptide supplementation during Rhizopus oryzae fermentation significantly improved fumaric acid production. Specifically, fumaric acid productivity was elevated by approximately 100%, fermentation duration was shortened from 72 to 36 h, while maintaining the final titer. Furthermore, transcriptome profile analysis and biochemical assays indicated that the overall capabilities of the stress defense systems (enzymatic and nonenzymatic) were significantly improved in R. oryzae. Consequently, glycolytic metabolism was distinctly enhanced, which eventually resulted in improved fumaric acid production and reduced fermentation duration. We expect our findings and efforts to provide essential insights into the optimization of the fermentation performance of filamentous fungi in industrial biotechnology and fermentation engineering.


Asunto(s)
Fumaratos , Rhizopus , Ácidos/metabolismo , Suplementos Dietéticos , Fermentación , Fumaratos/metabolismo , Hongos/metabolismo , Péptidos/metabolismo
18.
Materials (Basel) ; 15(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35591518

RESUMEN

High-crystalline-quality wide-bandgap metal halide perovskite materials that achieve superior performance in perovskite solar cells (PSCs) have been widely explored. Precursor concentration plays a crucial role in the wide-bandgap perovskite crystallization process. Herein, we investigated the influence of precursor concentration on the morphology, crystallinity, optical property, and defect density of perovskite materials and the photoelectric performance of solar cells. We found that the precursor concentration was the key factor for accurately controlling the nucleation and crystal growth process, which determines the crystallization of perovskite materials. The precursor concentration based on Cs0.05FA0.8MA0.15Pb(I0.84Br0.16)3 perovskite was controlled from 0.8 M to 2.3 M. The perovskite grains grow larger with the increase in concentration, while the grain boundary and bulk defect decrease. After regulation and optimization, the champion PSC with the 2.0 M precursor concentration exhibits a power conversion efficiency (PCE) of 21.13%. The management of precursor concentration provides an effective way for obtaining high-crystalline-quality wide-bandgap perovskite materials and high-performance PSCs.

19.
Science ; 375(6584): 1053-1058, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35143257

RESUMEN

Bivalent genes are ready for activation upon the arrival of developmental cues. Here, we report that BEND3 is a CpG island (CGI)-binding protein that is enriched at regulatory elements. The cocrystal structure of BEND3 in complex with its target DNA reveals the structural basis for its DNA methylation-sensitive binding property. Mouse embryos ablated of Bend3 died at the pregastrulation stage. Bend3 null embryonic stem cells (ESCs) exhibited severe defects in differentiation, during which hundreds of CGI-containing bivalent genes were prematurely activated. BEND3 is required for the stable association of polycomb repressive complex 2 (PRC2) at bivalent genes that are highly occupied by BEND3, which suggests a reining function of BEND3 in maintaining high levels of H3K27me3 at these bivalent genes in ESCs to prevent their premature activation in the forthcoming developmental stage.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/metabolismo , Proteínas Represoras/metabolismo , Activación Transcripcional , Animales , Cromatina/metabolismo , Islas de CpG , Cristalografía por Rayos X , ADN/química , ADN/metabolismo , Metilación de ADN , Células Madre Embrionarias/citología , Elementos de Facilitación Genéticos , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Histonas/metabolismo , Metilación , Ratones , Complejo Represivo Polycomb 2/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Dominios Proteicos , RNA-Seq , Proteínas Represoras/química , Proteínas Represoras/genética , Regulación hacia Arriba
20.
Mater Today Bio ; 13: 100179, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34938993

RESUMEN

The precise fabrication of artificially designed molecular complexes into ordered structures resembling their natural counterparts would find broad applications but remains a major challenge in the field. Here we genetically design chitin-binding domain (CBD)-containing amyloid proteins, and rationally fabricate well-ordered CBD-containing functional amyloid-chitin complex structures by coupling a top-down manufacturing process with a bottom-up self-assembly. Our fabrication approach starts with the dissolution of both CBD-containing functional amyloid and chitin in hexafluoroisopropanol (HFIP) to make a hybrid ink. This hybrid ink platform, coupled with multiple fabrication methods including airbrushing, electrospinning and soft-lithography, produces a series of unique freestanding structures. The structural features of the products, such as the ability to direct the light path and mimicking of the extracellular matrix enable applications in functional light gratings and cell culture, respectively. Further genetic engineering of the protein component allowed tunable functionalization of these materials, including nanoparticle immobilization and protein conjugation, resulting in broad applications in electronic devices and enzyme immobilization. Our technological platform can drive new advances in biocatalysis, tissue engineering, biomedicine, photonics and electronics.

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