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1.
EMBO J ; 41(23): e112338, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36254605

RESUMEN

A defining characteristic of mammalian prions is their capacity for self-sustained propagation. Theoretical considerations and experimental evidence suggest that prion propagation is modulated by cell-autonomous and non-autonomous modifiers. Using a novel quantitative phospholipase protection assay (QUIPPER) for high-throughput prion measurements, we performed an arrayed genome-wide RNA interference (RNAi) screen aimed at detecting cellular host-factors that can modify prion propagation. We exposed prion-infected cells in high-density microplates to 35,364 ternary pools of 52,746 siRNAs targeting 17,582 genes representing the majority of the mouse protein-coding transcriptome. We identified 1,191 modulators of prion propagation. While 1,151 modified the expression of both the pathological prion protein, PrPSc , and its cellular counterpart, PrPC , 40 genes selectively affected PrPSc . Of the latter 40 genes, 20 augmented prion production when suppressed. A prominent limiter of prion propagation was the heterogeneous nuclear ribonucleoprotein Hnrnpk. Psammaplysene A (PSA), which binds Hnrnpk, reduced prion levels in cultured cells and protected them from cytotoxicity. PSA also reduced prion levels in infected cerebellar organotypic slices and alleviated locomotor deficits in prion-infected Drosophila melanogaster expressing ovine PrPC . Hence, genome-wide QUIPPER-based perturbations can discover actionable cellular pathways involved in prion propagation. Further, the unexpected identification of a prion-controlling ribonucleoprotein suggests a role for RNA in the generation of infectious prions.


Asunto(s)
Enfermedades por Prión , Priones , Ratones , Animales , Ovinos/genética , Priones/genética , Priones/metabolismo , Drosophila melanogaster/genética , Ribonucleoproteínas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Enfermedades por Prión/genética , Enfermedades por Prión/patología , Mamíferos/genética
2.
Nano Lett ; 24(14): 4256-4264, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38557048

RESUMEN

Biological materials exhibit fascinating mechanical properties for intricate interactions at multiple interfaces to combine superb toughness with wondrous strength and stiffness. Recently, strong interlayer entanglement has emerged to replicate the powerful dissipation of natural proteins and alleviate the conflict between strength and toughness. However, designing intricate interactions in a strong entanglement network needs to be further explored. Here, we modulate interlayer entanglement by introducing multiple interactions, including hydrogen and ionic bonding, and achieve ultrahigh mechanical performance of graphene-based nacre fibers. Two essential modulating trends are directed. One is modulating dynamic hydrogen bonding to improve the strength and toughness up to 1.58 GPa and 52 MJ/m3, simultaneously. The other is tailoring ionic coordinating bonding to raise the strength and stiffness, reaching 2.3 and 253 GPa. Modulating various interactions within robust entanglement provides an effective approach to extend performance limits of bioinspired nacre and optimize multiscale interfaces in diverse composites.

3.
BMC Immunol ; 25(1): 10, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297222

RESUMEN

PURPOSE: More than 90% of patients with diabetes worldwide are type 2 diabetes (T2D), which is caused by insulin resistance or impaired producing insulin by pancreatic ß cells. T2D and its complications, mainly large cardiovascular (LCV) and kidney (Ne) complications, are the major cause of death in diabetes patients. Recently, the dysregulation of peripheral T cell immune homeostasis was found in most T2D patients. However, the characteristics of T-cell receptors (TCR) remain largely unexplored in T2D patients. PATIENTS AND METHODS: Here we investigated the TCR repertoire using high-throughput sequencing in peripheral blood collected from T2D patient with (8 LCV and 7 Ne) or without complications. RESULTS: Our analysis of TCR repertoires in peripheral blood samples showed that TCR profiles in T2D patients with complications tended to be single and specific compared to controls, according to the characteristics of TCR repertoire in V-J combination number, diversity, principal component analysis (PCA) and differential genes. And we identified some differentially expressed V-J gene segments and amino acid clonotypes, which had the potential to contribute to distinguishing T2D patient with or without complications. As the progression of the disease, we found that the profiling of TCR repertoire was also differential between T2D patients with LVD and Ne complications base on this pilot analysis. CONCLUSION: This study demonstrated the protentional unique property of TCR repertoire in peripheral blood of T2D patient with and without complications, or T2D patients with LVD and Ne complications, which provided the possibility for future improvements in immune-related diagnosis and therapy for T2D complications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Linfocitos T , Humanos , Receptores de Antígenos de Linfocitos T/genética , Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T alfa-beta/genética
4.
Small ; : e2400415, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698600

RESUMEN

Highly flexible and superelastic aerogels at large deformation have become urgent mechanical demands in practical uses, but both properties are usually exclusive. Here a trans-scale porosity design is proposed in graphene nanofibrous aerogels (GNFAs) to break the trade-off between high flexibility and superelasticity. The resulting GNFAs can completely recover after 1000 fatigue cycles at 60% folding strain, and notably maintain excellent structural integrity after 10000 cycles at 90% compressive strain, outperforming most of the reported aerogels. The mechanical robustness is demonstrated to be derived from the trans-scale porous structure, which is composed of hyperbolic micropores and porous nanofibers to enable the large elastic deformation capability. It is further revealed that flexible and superelastic GNFAs exhibit high sensitivity and ultrastability as an electrical sensors to detect tension and flexion deformation. As proof, The GNFA sensor is implemented onto a human finger and achieves the intelligent recognition of sign language with high accuracy by multi-layer artificial neural network. This study proposes a highly flexible and elastic graphene aerogel for wearable human-machine interfaces in sensor technology.

5.
BMC Cancer ; 24(1): 685, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840106

RESUMEN

BACKGROUND: Gastric cancer is one of the most common tumors worldwide, and most patients are deprived of treatment options when diagnosed at advanced stages. PRDM14 has carcinogenic potential in breast and non-small cell lung cancer. however, its role in gastric cancer has not been elucidated. METHODS: We aimed to elucidate the expression of PRDM14 using pan-cancer analysis. We monitored the expression of PRDM14 in cells and patients using quantitative polymerase chain reaction, western blotting, and immunohistochemistry. We observed that cell phenotypes and regulatory genes were influenced by PRDM14 by silencing PRDM14. We evaluated and validated the value of the PRDM14-derived prognostic model. Finally, we predicted the relationship between PRDM14 and small-molecule drug responses using the Connectivity Map and The Genomics of Drug Sensitivity in Cancer databases. RESULTS: PRDM14 was significantly overexpressed in gastric cancer, which identified in cell lines and patients' tissues. Silencing the expression of PRDM14 resulted in apoptosis promotion, cell cycle arrest, and inhibition of the growth and migration of GC cells. Functional analysis revealed that PRDM14 acts in epigenetic regulation and modulates multiple DNA methyltransferases or transcription factors. The PRDM14-derived differentially expressed gene prognostic model was validated to reliably predict the patient prognosis. Nomograms (age, sex, and PRDM14-risk score) were used to quantify the probability of survival. PRDM14 was positively correlated with sensitivity to small-molecule drugs such as TPCA-1, PF-56,227, mirin, and linsitinib. CONCLUSIONS: Collectively, our findings suggest that PRDM14 is a positive regulator of gastric cancer progression. Therefore, it may be a potential therapeutic target for gastric cancer.


Asunto(s)
Proteínas de Unión al ADN , Regulación Neoplásica de la Expresión Génica , Neoplasias Gástricas , Factores de Transcripción , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Humanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Pronóstico , Línea Celular Tumoral , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Femenino , Masculino , Nomogramas , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Epigénesis Genética
6.
Environ Sci Technol ; 58(19): 8393-8403, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38691770

RESUMEN

The chemistry of ozone (O3) on indoor surfaces leads to secondary pollution, aggravating the air quality in indoor environments. Here, we assess the heterogeneous chemistry of gaseous O3 with glass plates after being 1 month in two different kitchens where Chinese and Western styles of cooking were applied, respectively. The uptake coefficients of O3 on the authentic glass plates were measured in the dark and under UV light irradiation typical for indoor environments (320 nm < λ < 400 nm) at different relative humidities. The gas-phase product compounds formed upon reactions of O3 with the glass plates were evaluated in real time by a proton-transfer-reaction quadrupole-interface time-of-flight mass spectrometer. We observed typical aldehydes formed by the O3 reactions with the unsaturated fatty acid constituents of cooking oils. The formation of decanal, 6-methyl-5-hepten-2-one (6-MHO), and 4-oxopentanal (4-OPA) was also observed. The employed dynamic mass balance model shows that the estimated mixing ratios of hexanal, octanal, nonanal, decanal, undecanal, 6-MHO, and 4-OPA due to O3 chemistry with authentic grime-coated kitchen glass surfaces are higher in the kitchen where Chinese food was cooked compared to that where Western food was cooked. These results show that O3 chemistry on greasy glass surfaces leads to enhanced VOC levels in indoor environments.


Asunto(s)
Contaminación del Aire Interior , Culinaria , Vidrio , Ozono , Compuestos Orgánicos Volátiles , Ozono/química , Vidrio/química , Contaminantes Atmosféricos
7.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526680

RESUMEN

Outdoor ozone transported indoors initiates oxidative chemistry, forming volatile organic products. The influence of ozone chemistry on indoor air composition has not been directly quantified in normally occupied residences. Here, we explore indoor ozone chemistry in a house in California with two adult inhabitants. We utilize space- and time-resolved measurements of ozone and volatile organic compounds (VOCs) acquired over an 8-wk summer campaign. Despite overall low indoor ozone concentrations (mean value of 4.3 ppb) and a relatively low indoor ozone decay constant (1.3 h-1), we identified multiple VOCs exhibiting clear contributions from ozone-initiated chemistry indoors. These chemicals include 6-methyl-5-hepten-2-one (6-MHO), 4-oxopentanal (4-OPA), nonenal, and C8-C12 saturated aldehydes, which are among the commonly reported products from laboratory studies of ozone interactions with indoor surfaces and with human skin lipids. These VOCs together accounted for ≥12% molecular yield with respect to house-wide consumed ozone, with the highest net product yield for nonanal (≥3.5%), followed by 6-MHO (2.7%) and 4-OPA (2.6%). Although 6-MHO and 4-OPA are prominent ozonolysis products of skin lipids (specifically squalene), ozone reaction with the body envelopes of the two occupants in this house are insufficient to explain the observed yields. Relatedly, we observed that ozone-driven chemistry continued to produce 6-MHO and 4-OPA even after the occupants had been away from the house for 5 d. These observations provide evidence that skin lipids transferred to indoor surfaces made substantial contributions to ozone reactivity in the studied house.


Asunto(s)
Contaminantes Atmosféricos/química , Monitoreo del Ambiente , Ozono/química , Compuestos Orgánicos Volátiles/química , Contaminantes Atmosféricos/aislamiento & purificación , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/prevención & control , Aldehídos/química , California/epidemiología , Humanos , Cetonas/química , Lípidos/química , Oxidación-Reducción/efectos de los fármacos , Ozono/aislamiento & purificación , Ozono/metabolismo , Escualeno/química , Compuestos Orgánicos Volátiles/aislamiento & purificación
8.
Nano Lett ; 23(8): 3352-3361, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37052245

RESUMEN

Natural materials teach that mechanical dissipative interactions relieve the conflict between strength and toughness and enable fabrication of strong yet tough artificial materials. Replicating natural nacre structure has yielded rich biomimetic materials; however, stronger interlayer dissipation still waits to be exploited to extend the performance limits of artificial nacre materials. Here, we introduce strong entanglement as a new artificial interlayer dissipative mechanism and fabricate entangled nacre materials with superior strength and toughness, across molecular to nanoscale nacre structures. The entangled graphene nacre fibers achieved high strength of 1.2 GPa and toughness of 47 MJ/m3, and films reached 1.5 GPa and 25 MJ/m3. Experiments and simulations reveal that strong entanglement can effectively dissipate interlayer energy to relieve the conflict between strength and toughness, acting as natural folded proteins. The strong interlayer entanglement opens up a new path for designing stronger and tougher artificial materials to mimic but surpass natural materials.

9.
Stroke ; 54(10): 2629-2639, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37586072

RESUMEN

BACKGROUND: Small extracellular vesicles (sEVs) derived from M2 microglia (M2-microglia-derived small extracellular vesicles [M2-sEVs]) contribute to central nervous system repair, although the underlying mechanism remains unknown. In this study, we aimed to identify the mechanism through which microRNA-124 (miR-124) carried in sEVs promotes neural stem cell (NSC) proliferation and neuronal differentiation in the ischemic mouse brain. METHODS: M2-sEVs with or without miR-124 knockdown were injected intravenously for 7 consecutive days after transient middle cerebral artery occlusion surgery. The atrophy volume, neurological score, and degree of neurogenesis were examined at different time points after ischemic attack. NSCs treated with different sEVs were subjected to proteomic analysis. Target protein concentrations were quantified, and subsequent bioinformatic analysis was conducted to explore the key signaling pathways. RESULTS: M2-sEV transplantation promoted functional neurological recovery following transient middle cerebral artery occlusion injury. M2-sEV treatment decreased the brain atrophy volume, neurological score, and mortality rate. The effect was reserved by knockdown of miR-124 in M2-sEVs. M2-sEVs promoted proliferation and differentiation of mature neuronal NSCs in vivo. Proteomic analysis of NSC samples treated with M2-sEVs with and without miR-124 knockdown revealed that AAK1 (adaptor-associated protein kinase 1) was the key responding protein in NSCs. The binding of AAK1 to Notch promoted the differentiation of NSCs into neurons rather than astrocytes. CONCLUSIONS: Our data suggest that AAK1/Notch is the key pathway in NSCs that responds to the miR-124 carried within M2-sEVs in the ischemic brain. M2-sEVs carrying ample quantities of miR-124 promote functional recovery after ischemic stroke by enhancing NSC proliferation and differentiation. Targeting of M2-sEVs could represent a potential therapeutic strategy for brain recovery.


Asunto(s)
Vesículas Extracelulares , Accidente Cerebrovascular Isquémico , MicroARNs , Células-Madre Neurales , Ratones , Animales , Microglía/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Proteómica , Diferenciación Celular , Vesículas Extracelulares/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo
10.
BMC Cancer ; 23(1): 1239, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102538

RESUMEN

BACKGROUND: Novel ADC drugs provide a new therapeutic strategy for gastric cancer.The present study aimed to analyze the clinical efficacy and drug toxicities of disitamab vedotin (RC48) plus immune checkpoint inhibitors(ICIs) and RC48 as third-line therapies and beyond for advanced and metastatic gastric cancer patients. METHODS: This was an observational multicenter real-world study.From August 2021 to January 2022,patients with HER2-positive or HER2-low advanced and metastatic gastric cancer and failed from two or more lines of prior therapy were enrolled and treated with RC48 plus ICIs or RC48. In this study, progression free survival(PFS) was the primary end point. Other evaluation indicators were objective response rate(ORR),disease control rate(DCR),overall survival(OS) and drug toxicities. RESULTS: 45 patients were enrolled,of which 25 patients received RC48 plus ICIs,20 patients received RC48.Patients who received RC48 plus ICIs obtained better ORR (36.0% vs. 10.0%, P = 0.044) and DCR (80.0% vs. 50.0%, P = 0.034) compared with RC48,and simultaneously,the median PFS in RC48 plus ICIs group were superior to RC48 group(6.2 m vs. 3.9 m).The median OS was not reached.No statistically differences were found between HER2-positive and HER2-low group with respect to ORR (27.3% vs. 16.7%, P = 0.464),DCR (66.7% vs. 66.7%, P = 1.000),median PFS(5.7 m vs. 4.3 m, P = 0.299).The most common adverse events (AEs) were decreased white blood count,decreased neutrophil count,fatigue,hypoaesthesia and alopecia.Grade 3-4 AEs occurred in 7(35.0%) patients of RC48 group and 10(40.0%) patients of RC48 plus ICIs group,respectively. CONCLUSION: Compared with RC48 monotherapy, ICIs plus RC48 demonstrated superior third-line and beyond therapeutic efficacy for HER2-positive or HER2-low advanced and metastatic gastric cancer patients with manageable safety.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Neoplasias del Bazo , Neoplasias Gástricas , Humanos , Inhibidores de Puntos de Control Inmunológico , Neoplasias Gástricas/tratamiento farmacológico , Alopecia
11.
Langmuir ; 39(34): 12166-12173, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37584281

RESUMEN

Understanding the dynamical behaviors of two-dimensional (2D) macromolecules is of fundamental importance for the precise modulation of their assembled structures and material performances. However, considerably less is known about how discrete macromolecular sheets aggregate into extended macroscopic assemblies in solutions. The absence of a quantitative description of the assembly process limits the precise structural control of assemblies. Here, we investigated the aggregation thermodynamic transition and kinetic behavior of 2D macromolecules in the model of single layer graphene oxide (GO). Combining Flory-Huggins theory with experimental observations, we unveiled the critical thermodynamic transition of GO to correlate with the solvent property. We proposed a theoretical falling-leaf model to quantitatively describe the kinetic aggregation process of 2D GO sheets. Experimental analysis validated the theoretical prediction that the thickness of GO aggregates has a power law relation with the poor solvent content. Our work provides a fundamental understanding of phase separation of 2D macromolecules and offers an insight into modulating the aggregated structures of their assembled materials.

12.
Crit Rev Food Sci Nutr ; : 1-13, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38117083

RESUMEN

Flavonoids are significant natural nutraceuticals and a key component of dietary supplements. Given that flavonoid glycosides are more plentiful in nature and less beneficial to human health than their aglycone counterparts, they serve as potential precursors for flavonoid production. Glycosidases have shown substantial potential within the food industry, particularly in enhancing the organoleptic properties of juice, wine, and tea. When applied to food resources, glycosidases can amplify their biological activities, thereby improving the performance of functional foods. This review provides up-to-date information on flavonoid glycosidases, including their catalytic mechanisms, biochemical properties, and natural sources, as well as their applications within the food industry. The use of flavonoid glycosidases in improving food quality is also reviewed.

13.
Environ Sci Technol ; 57(35): 13104-13113, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37610659

RESUMEN

Ozone reactions on human body surfaces produce volatile organic compounds (VOCs) that influence indoor air quality. However, the dependence of VOC emissions on the ozone concentration has received limited attention. In this study, we conducted 36 sets of single-person chamber experiments with three volunteers exposed to ozone concentrations ranging from 0 to 32 ppb. Emission fluxes from human body surfaces were measured for 11 targeted skin-oil oxidation products. For the majority of these products, the emission fluxes linearly correlated with ozone concentration, indicating a constant surface yield (moles of VOC emitted per mole of ozone deposited). However, for the second-generation oxidation product 4-oxopentanal, a higher surface yield was observed at higher ozone concentrations. Furthermore, many VOCs have substantial emissions in the absence of ozone. Overall, these results suggest that the complex surface reactions and mass transfer processes involved in ozone-dependent VOC emissions from the human body can be represented using a simplified parametrization based on surface yield and baseline emission flux. Values of these two parameters were quantified for targeted products and estimated for other semiquantified VOC signals, facilitating the inclusion of ozone/skin oil chemistry in indoor air quality models and providing new insights on skin oil chemistry.


Asunto(s)
Ozono , Compuestos Orgánicos Volátiles , Humanos , Cuerpo Humano
14.
Environ Sci Technol ; 57(8): 3260-3269, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36796310

RESUMEN

Semivolatile organic compounds (SVOCs) represent an important class of indoor pollutants. The partitioning of SVOCs between airborne particles and the adjacent air influences human exposure and uptake. Presently, little direct experimental evidence exists about the influence of indoor particle pollution on the gas-particle phase partitioning of indoor SVOCs. In this study, we present time-resolved gas- and particle-phase distribution data for indoor SVOCs in a normally occupied residence using semivolatile thermal desorption aerosol gas chromatography. Although SVOCs in indoor air are found mostly in the gas phase, we show that indoor particles from cooking, candle use, and outdoor particle infiltration strongly affect the gas-particle phase distribution of specific indoor SVOCs. From gas- and particle-phase measurements of SVOCs spanning a range of chemical functionalities (alkanes, alcohols, alkanoic acids, and phthalates) and volatilities (vapor pressures from 10-13 to 10-4 atm), we find that the chemical composition of the airborne particles influences the partitioning of individual SVOC species. During candle burning, the enhanced partitioning of gas-phase SVOCs to indoor particles not only affects the particle composition but also enhances surface off-gassing, thereby increasing the total airborne concentration of specific SVOCs, including diethylhexyl phthalate.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Dietilhexil Ftalato , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Contaminación del Aire Interior/análisis , Dietilhexil Ftalato/análisis , Contaminantes Atmosféricos/análisis , Gases/análisis , Culinaria
15.
Molecules ; 28(9)2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37175245

RESUMEN

As a new generation of green media and functional materials, ionic liquids (ILs) have been extensively investigated in scientific and industrial communities, which have found numerous ap-plications in polymeric materials. On the one hand, much of the research has determined that ILs can be applied to modify polymers which use nanofillers such as carbon black, silica, graphene oxide, multi-walled carbon nanotubes, etc., toward the fabrication of high-performance polymer composites. On the other hand, ILs were extensively reported to be utilized to fabricate polymeric materials with improved thermal stability, thermal and electrical conductivity, etc. Despite substantial progress in these areas, summary and discussion of state-of-the-art functionalities and underlying mechanisms of ILs are still inadequate. In this review, a comprehensive introduction of various fillers modified by ILs precedes a systematic summary of the multifunctional applications of ILs in polymeric materials, emphasizing the effect on vulcanization, thermal stability, electrical and thermal conductivity, selective permeability, electromagnetic shielding, piezoresistive sensitivity and electrochemical activity. Overall, this review in this area is intended to provide a fundamental understanding of ILs within a polymer context based on advantages and disadvantages, to help researchers expand ideas on the promising applications of ILs in polymer fabrication with enormous potential.

16.
Plant Cell Environ ; 45(6): 1843-1861, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35199374

RESUMEN

Stomatal movement participates in plant immunity by directly affecting the invasion of bacteria, but the genes that regulate stomatal immunity have not been well identified. Here, we characterised the function of the bZIP59 transcription factor from Arabidopsis thaliana, which is constitutively expressed in guard cells. The bzip59 mutant is partially impaired in stomatal closure induced by Pseudomonas syringae pv. tomato strain (Pst) DC3000 and is more susceptible to Pst DC3000 infection. By contrast, the line overexpressing bZIP59 enhances resistance to Pst DC3000 infection. Furthermore, the bzip59 mutant is also partially impaired in stomatal closure induced by flagellin flg22 derived from Pst DC3000, and epistasis analysis revealed that bZIP59 acts upstream of reactive oxygen species (ROS) and nitric oxide (NO) and downstream of salicylic acid signalling in flg22-induced stomatal closure. In addition, the bzip59 mutant showed resistance and sensitivity to Sclerotinia sclerotiorum and Tobacco mosaic virus that do not invade through stomata, respectively. Collectively, our results demonstrate that bZIP59 plays an important role in the stomatal immunity and reveal that the same transcription factor can positively and negatively regulate disease resistance against different pathogens.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Solanum lycopersicum , Arabidopsis/genética , Arabidopsis/inmunología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/inmunología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/inmunología , Solanum lycopersicum/metabolismo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Estomas de Plantas/genética , Estomas de Plantas/inmunología , Pseudomonas syringae/fisiología , Factores de Transcripción/genética
17.
Environ Sci Technol ; 56(22): 15427-15436, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36327170

RESUMEN

Volatile methyl siloxanes (VMS) are ubiquitous in indoor environments due to their use in personal care products. This paper builds on previous work identifying sources of VMS by synthesizing time-resolved proton-transfer reaction time-of-flight mass spectrometer VMS concentration measurements from four multiweek indoor air campaigns to elucidate emission sources and removal processes. Temporal patterns of VMS emissions display both continuous and episodic behavior, with the relative importance varying among species. We find that the cyclic siloxane D5 is consistently the most abundant VMS species, mainly attributable to personal care product use. Two other cyclic siloxanes, D3 and D4, are emitted from oven and personal care product use, with continuous sources also apparent. Two linear siloxanes, L4 and L5, are also emitted from personal care product use, with apparent additional continuous sources. We report measurements for three other organosilicon compounds found in personal care products. The primary air removal pathway of the species examined in this paper is ventilation to the outdoors, which has implications for atmospheric chemistry. The net removal rate is slower for linear siloxanes, which persist for days indoors after episodic release events. This work highlights the diversity in sources of organosilicon species and their persistence indoors.


Asunto(s)
Compuestos de Organosilicio , Siloxanos , Siloxanos/análisis , Monitoreo del Ambiente , Ventilación
18.
Indoor Air ; 32(11): e13153, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36437662

RESUMEN

We performed a cross-sectional survey of 2143 female students in a university in Tianjin, China regarding perceived air quality (PAQ) and sick building syndrome (SBS) symptoms in the student dormitory. The prevalence of general, mucosal, and skin symptoms was 22.1%, 21.9%, and 26.3%, respectively. The three most prevalent PAQ complaints were "dry air" (48.9% often), "stuffy odor" (18.2%), and "other unpleasant odors" (5.1%), and they were significant risk factors for 11-12 out of 12 SBS symptoms (adjusted odds ratios [AOR]: 1.6-5.8). Survey data of 1471 undergraduates, whose dorms were of uniform layout and furnishing, were used to further investigate the influences of occupancy level and occupant behaviors on PAQ and SBS symptoms. Frequent use of air freshener/perfume was a significant risk factor for "dry air," less frequent room cleaning and higher occupancy density were significant risk factors for "stuffy odor," and less natural ventilation was a significant risk factor for both "stuffy odor" and "pungent odor." These factors were also significantly associated with some SBS symptoms. In particular, the use of air freshener/perfume exhibited a significant dose-response pattern with "fatigue" (sometimes: AOR 1.3; often: AOR 2.0) and with "irritated, stuffy, or runny nose" (sometimes: AOR 1.6; often: AOR 2.2).


Asunto(s)
Contaminación del Aire Interior , Contaminación del Aire , Perfumes , Síndrome del Edificio Enfermo , Humanos , Femenino , Síndrome del Edificio Enfermo/epidemiología , Síndrome del Edificio Enfermo/etiología , Estudios Transversales , Contaminación del Aire Interior/efectos adversos , Estudiantes
19.
Nano Lett ; 21(12): 5116-5125, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34126742

RESUMEN

Achieving high spinning speed is critical to the production efficiency and viable application of fiber species. Graphene fiber (GF) has recently emerged as a carbonaceous fiber with excellent functionality. However, the extremely low wet spinning speed of GF has limited its applications. We realized high-speed blow spinning of neat GF and fabric by modulating the rheological properties of the graphene oxide (GO) dispersion. We achieved a speed of 556 m min-1, 2 orders of magnitude faster than that for wet spinning. We chose ultrahigh molecular weight polymers as transient additives to circumvent the intrinsic barrier effect of GO and achieve high spinning dope stretchability at low polymer percentages-down to 25 wt %. Minimizing the polymer additive content ensures the high electrical/thermal conductivity of the blow-spun fiber and fabric. This work provides insight into the unique flow properties of 2D sheets and will promote the efficient production of graphene-based fibrous materials.


Asunto(s)
Grafito , Polímeros , Textiles
20.
Plant J ; 104(4): 932-949, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32808386

RESUMEN

Brassica napus is currently cultivated as an important ornamental crop in China. Flower color has attracted much attention in rapeseed genetics and breeding. Here, we characterize an orange-flowered mutant of B. napus that exhibits an altered carotenoid profile in its petals. As revealed by map-based cloning, the change in color from yellow to orange is attributed to the loss of BnaC09.ZEP (zeaxanthin epoxidase) and a 1695-bp deletion in BnaA09.ZEP. HPLC analysis, genetic complementation and CRISPR/Cas9 experiments demonstrated that BnaA09.ZEP and BnaC09.ZEP have similar functions, and the abolishment of both genes led to a substantial increase in lutein content and a sharp decline in violaxanthin content in petals but not leaves. BnaA09.ZEP and BnaC09.ZEP are predominantly expressed in floral tissues, whereas their homologs, BnaA07.ZEP and BnaC07.ZEP, mainly function in leaves, indicating redundancy and tissue-specific diversification of BnaZEP function. Transcriptome analysis in petals revealed differences in the expression of carotenoid and flavonoid biosynthesis-related genes between the mutant and its complementary lines. Flavonoid profiles in the petals of complementary lines were greatly altered compared to the mutant, indicating potential cross-talk between the regulatory networks underlying the carotenoid and flavonoid pathways. Additionally, our results indicate that there is functional compensation by BnaA07.ZEP and BnaC07.ZEP in the absence of BnaA09.ZEP and BnaC09.ZEP. Cloning and characterization of BnaZEPs provide insights into the molecular mechanisms underlying flower pigmentation in B. napus and would facilitate breeding of B. napus varieties with higher ornamental value.


Asunto(s)
Brassica napus/genética , Carotenoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Oxidorreductasas/metabolismo , Brassica napus/enzimología , Brassica napus/fisiología , Sistemas CRISPR-Cas , Flavonoides/metabolismo , Flores/enzimología , Flores/genética , Flores/fisiología , Silenciador del Gen , Luteína/metabolismo , Oxidorreductasas/genética , Pigmentación/genética , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xantófilas/metabolismo
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