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1.
Proc Natl Acad Sci U S A ; 121(8): e2316716121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38349874

RESUMO

Understanding the molecular-level mechanisms involved in transmembrane ion selectivity is essential for optimizing membrane separation performance. In this study, we reveal our observations regarding the transmembrane behavior of Li+ and Mg2+ ions as a response to the changing pore solvation abilities of the covalent-organic-framework (COF) membranes. These abilities were manipulated by adjusting the lengths of the oligoether segments attached to the pore channels. Through comparative experiments, we were able to unravel the relationships between pore solvation ability and various ion transport properties, such as partitioning, conduction, and selectivity. We also emphasize the significance of the competition between Li+ and Mg2+ with the solvating segments in modulating selectivity. We found that increasing the length of the oligoether chain facilitated ion transport; however, it was the COF membrane with oligoether chains containing two ethylene oxide units that exhibited the most pronounced discrepancy in transmembrane energy barrier between Li+ and Mg2+, resulting in the highest separation factor among all the evaluated membranes. Remarkably, under electro-driven binary-salt conditions, this specific COF membrane achieved an exceptional Li+/Mg2+ selectivity of up to 1352, making it one of the most effective membranes available for Li+/Mg2+ separation. The insights gained from this study significantly contribute to advancing our understanding of selective ion transport within confined nanospaces and provide valuable design principles for developing highly selective COF membranes.

2.
Small ; 20(25): e2310791, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38214692

RESUMO

The evolution of porous membranes has revitalized their potential application in sustainable osmotic-energy conversion. However, the performance of multiporous membranes deviates significantly from the linear extrapolation of single-pore membranes, primarily due to the occurrence of ion-concentration polarization (ICP). This study proposes a robust strategy to overcome this challenge by incorporating photoelectric responsiveness into permselective membranes. By introducing light-induced electric fields within the membrane, the transport of ions is accelerated, leading to a reduction in the diffusion boundary layer and effectively mitigating the detrimental effects of ICP. The developed photoelectric-responsive covalent-organic-framework membranes exhibit an impressive output power density of 69.6 W m-2 under illumination, surpassing the commercial viability threshold by ≈14-fold. This research uncovers a previously unexplored benefit of integrating optical electric conversion with reverse electrodialysis, thereby enhancing energy conversion efficiency.

3.
Chemistry ; 29(63): e202302460, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37605607

RESUMO

Insufficient access to clean water and resources has emerged as one of the most pressing issues affecting people globally. Membrane-based ion separation has become a focal point of research for the generation of fresh water and the extraction of energy elements. This Review encapsulates recent advancements in the selective ion transport of covalent organic framework (COF) membranes, accomplished by strategically pairing diverse monomers to create membranes with various pore sizes and environments for specific purposes. We first discuss the merits of using COF materials as a basis for fabricating membranes for ion separation. We then explore the development of COF membranes in areas such as desalination, acid recovery, and energy element extraction, with a particular emphasis on the fundamental principles of membrane design. Lastly, we address both theoretical and practical challenges, as well as potential opportunities in the targeted design of ion-selective membranes. The goal of this Review is to stimulate future investigative efforts in this field, which is of significant scientific and strategic importance.

4.
Respir Res ; 23(1): 328, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463140

RESUMO

BACKGROUND: Bronchiectasis is a highly heterogeneous chronic airway disease with marked geographic and ethnic variations. Most influential cohort studies to date have been performed in Europe and USA, which serve as the examples for developing a cohort study in China where there is a high burden of bronchiectasis. The Establishment of China Bronchiectasis Registry and Research Collaboration (BE-China) is designed to: (1) describe the clinical characteristics and natural history of bronchiectasis in China and identify the differences of bronchiectasis between the western countries and China; (2) identify the risk factors associated with disease progression in Chinese population; (3) elucidate the phenotype and endotype of bronchiectasis by integrating the genome, microbiome, proteome, and transcriptome with detailed clinical data; (4) facilitate large randomized controlled trials in China. METHODS: The BE-China is an ongoing prospective, longitudinal, multi-center, observational cohort study aiming to recruit a minimum of 10,000 patients, which was initiated in January 2020 in China. Comprehensive data, including medical history, aetiological testing, lung function, microbiological profiles, radiological scores, comorbidities, mental status, and quality of life (QoL), will be collected at baseline. Patients will be followed up annually for up to 10 years to record longitudinal data on outcomes, treatment patterns and QoL. Biospecimens, if possible, will be collected and stored at - 80 °C for further research. Up to October 2021, the BE-China has enrolled 3758 patients, and collected 666 blood samples and 196 sputum samples from 91 medical centers. The study protocol has been approved by the Shanghai Pulmonary Hospital ethics committee, and all collaborating centers have received approvals from their local ethics committee. All patients will be required to provide written informed consent to their participation. CONCLUSIONS: Findings of the BE-China will be crucial to reveal the clinical characteristics and natural history of bronchiectasis and facilitate evidence-based clinical practice in China. Trial registration Registration Number in ClinicalTrials.gov: NCT03643653.


Assuntos
Bronquiectasia , Humanos , Bronquiectasia/diagnóstico , Bronquiectasia/epidemiologia , China/epidemiologia , Estudos de Coortes , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Estudos Prospectivos , Qualidade de Vida , Sistema de Registros
5.
PLoS Genet ; 15(1): e1007423, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30615614

RESUMO

Many animals exploit several niches sequentially during their life cycles, a fitness referred to as ontogenetic niche shift (ONS). To successfully accomplish ONS, transition between development stages is often coupled with changes in one or more primitive, instinctive behaviors. Yet, the underlining molecular mechanisms remain elusive. We show here that Leptinotarsa decemlineata larvae finish their ONS at the wandering stage by leaving the plant and pupating in soil. At middle wandering phase, larvae also switch their phototactic behavior, from photophilic at foraging period to photophobic. We find that enhancement of juvenile hormone (JH) signal delays the phototactic switch, and vise verse. Moreover, RNA interference (RNAi)-aided knockdown of LdPTTH (prothoracicotropic hormone gene) or LdTorso (PTTH receptor gene) impairs avoidance response to light, a phenotype nonrescuable by 20-hydroxyecdysone. Consequently, the RNAi beetles pupate at the soil surface or in shallow layer of soil, with most of them failing to construct pupation chambers. Furthermore, a combination of depletion of LdPTTH/LdTorso and disturbance of JH signal causes no additive effects on light avoidance response and pupation site selection. Finally, we establish that TrpA1 (transient receptor potential (TRP) cation channel) is necessary for light avoidance behavior, acting downstream of PTTH. We conclude that JH/PTTH cascade concomitantly regulates metamorphosis and the phototaxis switch, to drive ONS of the wandering beetles from plant into soil to start the immobile pupal stage.


Assuntos
Hormônios de Inseto/genética , Hormônios Juvenis/genética , Metamorfose Biológica/genética , Fototaxia , Animais , Besouros/genética , Besouros/crescimento & desenvolvimento , Ecdisterona/metabolismo , Aptidão Genética/genética , Proteínas de Insetos/genética , Larva/genética , Larva/crescimento & desenvolvimento , Pupa/genética , Pupa/crescimento & desenvolvimento , Interferência de RNA , Transdução de Sinais
6.
Angew Chem Int Ed Engl ; 61(18): e202116910, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35179288

RESUMO

A vast amount of energy can be extracted from the untapped low-grade heat from sources below 100 °C and the Gibbs free energy from salinity gradients. Therefore, a process for simultaneous and direct conversion of these energies into electricity using permselective membranes was developed in this study. These membranes screen charges of ion flux driven by the combined salinity and temperature gradients to achieve thermo-osmotic energy conversion. Increasing the charge density in the pore channels enhanced the permselectivity and ion conductance, leading to a larger osmotic voltage and current. A 14-fold increase in power density was achieved by adjusting the ionic site population of covalent organic framework (COF) membranes. The optimal COF membrane was operated under simulated estuary conditions at a temperature difference of 60 K, which yielded a power density of ≈231 W m-2 , placing it among the best performing upscaled membranes. The developed system can pave the way to the utilization of the enormous supply of untapped osmotic power and low-grade heat energy, indicating the tremendous potential of using COF membranes for energy conversion applications.

7.
Org Biomol Chem ; 17(34): 7938-7942, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31417995

RESUMO

A series of C-2' modified cinchonine-derived phase-transfer catalysts were synthesized and used in the enantioselective photo-organocatalytic aerobic oxidation of ß-dicarbonyl compounds with excellent yields (up to 97%) and high enantioselectivities (up to 90% ee). Furthermore, the reaction was carried out in a flow photomicroreactor, in which the heterogeneous gas-liquid-liquid asymmetric photocatalytic oxidation reaction was performed affording good yields (up to 97%) and enantioselectivities (up to 86% ee) within 0.89 min.

8.
Plant Cell Rep ; 36(4): 529-542, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28155114

RESUMO

KEY MESSAGE: Over-expression of SlJA2 decreased the accumulation of SA, which resulted in significant physiological and gene expression changes in transgenic tobacco plants, leading to the decreased heat tolerance of transgenic tobacco. NAC family, the largest transcription factors in plants, responses to different environmental stimuli. Here, we isolated a typical NAC transcription factor (SlJA2) from tomato and got transgenic tobacco with SlJA2 over-expression. Expression of SlJA2 was induced by heat stress (42 °C), chilling stress (4 °C), drought stress, osmotic stress, abscisic acid, and salicylic acid. Over-expression of SlJA2 decreased the accumulation of salicylic acid by regulating expression of salicylic acid degradation gene under heat stress. Compared to WT plants, stomatal apertures and water loss increased in transgenic plants, and the damage of photosynthetic apparatus and chlorophyll breakdown were more serious in transgenic plants under heat stress. Meanwhile, more H2O2 and O2·- were accumulated transgenic plants and proline synthesis was restricted, which resulted in more serious oxidative damage compared to WT. qRT-PCR analysis showed that over-expression of SlJA2 could down-regulate genes involved in reactive oxygen species scavenging, proline biosynthesis, and response to heat stress. All the above results indicated that SlJA2 may be a negative regulator responded to plant's heat tolerance. Thus, this study provides new insight into roles of NAC family member in plant response to abiotic stress.


Assuntos
Expressão Gênica , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Transdução de Sinais/genética , Estresse Fisiológico/genética , Termotolerância/genética , Secas , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Nicotiana/efeitos dos fármacos , Nicotiana/genética
9.
Pestic Biochem Physiol ; 143: 173-180, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183589

RESUMO

To accomplish consistent, long-term, integrated management (IPM) of the Colorado potato beetle, Leptinotarsa decemlineata (Say), research assessing the potential of novel, IPM-compatible insecticides is essential. Novaluron is a potent benzoylurea insecticide. In the present paper, we found that novaluron ingestion by the fourth-instar larvae inhibited foliage consumption, reduced larval fresh weight, and delayed development period, in a dose dependent manner. Most of the resulting larvae fail to pupate, and died at prepupae stage, with larvicidal activity comparable with those of cyhalothrin and spinosad but lower than those of fipronil and abamectin. Moreover, many surviving pupae that fed novaluron failed to emerge as adults, in a dose dependent pattern. Furthermore, feeding of novaluron significantly decreased chitin contents in body carcass (without midgut) and integument specimen, whereas the chitin concentration in the midgut peritrophic matrix was not affected. Furthermore, uridine diphosphate-N-acetylglucosamine-pyrophosphorylase gene (LdUAP1) and chitin synthase Aa (LdChSAa), which were mainly responsible for chitin biosynthesis in ectodermally-derived tissues, were surpressed and activated respectively after novaluron ingestion. Therefore, novaluron is an effective benzoylurea insecticide to L. decemlineata fourth-instar larvae. It inhibited chitin biosynthesis in ectodermally-derived tissues, disrupted ecdysis, impaired pupation and adult emergence, and led to death in juvenile life stages.


Assuntos
Quitina/biossíntese , Besouros/efeitos dos fármacos , Inseticidas/toxicidade , Compostos de Fenilureia/toxicidade , Animais , Quitina Sintase/metabolismo , Besouros/metabolismo , Ingestão de Alimentos , Larva/efeitos dos fármacos , Larva/metabolismo
10.
Pestic Biochem Physiol ; 133: 26-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27742358

RESUMO

Glutathione S-transferases (GSTs) is a family of multifunctional enzymes that are involved in detoxification of poisonous compounds. In the present paper, the Leptinotarsa decemlineata genome and transcriptome dataset were mined and 30 GST genes were identified. These GSTs belonged to cytosolic (29 genes) and microsomal (1 gene) classes. Among them 3 GSTs (LdGSTe2, LdGSTs4, and LdGSTo3) possessed splice variants. Of the 29 cytosolic LdGSTs, 3, 10, 5, 4, 4, and 1 members were classified as delta, epsilon, omega, sigma, theta, and zeta subclasses respectively, along with 2 unclassified genes. Phylogenetic analysis suggest that epsilon, omega and sigma subclasses appear to undergo species-specific bloom. Moreover, most epsilon, omega and sigma GSTs are tandemly arranged in three chromosome scaffolds. To find GST candidates involving in insecticide detoxification, we tested the mRNA levels of 20 GST transcripts under stress of cyhalothrin, fipronil or endosulfan. Out of them, LdGSTe2a, LdGSTe2b, LdGSTo5 and LdGSTt1 were significantly overexpressed after exposure to each of the three insecticides. Two other genes were respectively upregulated after cyhalothrin (LdGSTe10 and LdGSTu2) or endosulfan (LdGSTd1 and LdGSTu2) treatment. The diversified expression responses to insecticide exposure suggest that the LdGSTs may depend on a functionally complex system to detoxify different classes of insecticides. In addition, our findings provide a base for a better understanding of the evolution of insecticide resistance, and functional research on specific GST genes.


Assuntos
Besouros/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Proteínas de Insetos/genética , Inseticidas/toxicidade , Animais , Besouros/efeitos dos fármacos , Besouros/enzimologia , DNA Complementar/genética , Endossulfano/toxicidade , Inativação Metabólica/genética , Nitrilas/toxicidade , Filogenia , Pirazóis/toxicidade , Piretrinas/toxicidade , Estresse Fisiológico , Transcriptoma
11.
Plant Cell Rep ; 33(1): 131-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24129846

RESUMO

KEY MESSAGE: Transgenic tomato plants overexpressing LeFAD3 sense and antisense sequences were generated. Salt stress suppressed the growth of WT and antisense plants to a higher extent than that in sense plants. In this study, we investigated the role of the LeFAD3-encoding ER-type omega-3 fatty acid desaturase in salt tolerance in tomato plants. We created transgenic tomato plants by overexpressing its sense and antisense sequences under the control of the cauliflower mosaic virus 35S promoter. Based on the results of northern and western blotting as well as quantitative reverse transcription-polymerase chain reaction, sense plants expressed more desaturase than wild-type (WT) plants, whereas antisense plants expressed less desaturase than WT. Salt stress suppressed the growth of both WT and antisense plants to a higher extent than that in sense plants, which can be attributed to the fact that sense plants performed better in maintaining the integrity of the membrane system, as revealed by electron microscopy. The concomitant increase in superoxide dismutase (EC 1.15.1.1) and ascorbate peroxidase (EC 1.11.1.7) may have alleviated the photoinhibition caused by the increased level of ROS in sense plants. Our results suggest that LeFAD3 overexpression can enhance the tolerance of early seedlings to salinity stress.


Assuntos
Retículo Endoplasmático/enzimologia , Ácidos Graxos Dessaturases/metabolismo , Salinidade , Tolerância ao Sal , Plântula/enzimologia , Solanum lycopersicum/enzimologia , Solanum lycopersicum/fisiologia , Ascorbato Peroxidases/metabolismo , Condutividade Elétrica , Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos Dessaturases/genética , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura , Plantas Geneticamente Modificadas , Tolerância ao Sal/efeitos dos fármacos , Tolerância ao Sal/genética , Plântula/efeitos dos fármacos , Plântula/fisiologia , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Superóxido Dismutase/metabolismo
12.
Sci Adv ; 10(39): eado8658, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39321297

RESUMO

Advancing membranes with enhanced solute-solute selectivity is essential for expanding membrane technology applications, yet it presents a notable challenge. Drawing inspiration from the unparalleled selectivity of biological systems, which benefit from the sophisticated spatial organization of functionalities, we posit that manipulating the arrangement of the membrane's building blocks, an aspect previously given limited attention, can address this challenge. We demonstrate that optimizing the face-to-face orientation of building blocks during the assembly of covalent-organic-framework (COF) membranes improves ion-π interactions with multivalent ions. This optimization leads to extraordinary selectivity in differentiating between monovalent cations and anions from their multivalent counterparts, achieving selectivity factors of 214 for K+/Al3+ and 451 for NO3-/PO43-. Leveraging this attribute, the COF membrane facilitates the direct extraction of NaCl from seawater with a purity of 99.57%. These findings offer an alternative approach for designing highly selective membrane materials, offering promising prospects for advancing membrane-based technologies.

13.
Nat Commun ; 15(1): 8137, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289381

RESUMO

Efficient energy conversion using ions as carriers necessitates membranes that sustain high permselectivity in high salinity conditions, which presents a significant challenge. This study addresses the issue by manipulating the linkages in covalent-organic-framework membranes, altering the distribution of electrostatic potentials and thereby influencing the short-range interactions between ions and membranes. We show that a charge-neutral covalent-organic-framework membrane with ß-ketoenamine linkages achieves record permselectivity in high salinity environments. Additionally, the membrane retains its permselectivity under temperature gradients, providing a method for converting low-grade waste heat into electrical energy. Experiments reveal that with a 3 M KCl solution and a 50 K temperature difference, the membrane generates an output power density of 5.70 W m-2. Furthermore, guided by a short-range ionic screening mechanism, the membrane exhibits adaptable permselectivity, allowing reversible and controllable operations by finely adjusting charge polarity and magnitude on the membrane's channel surfaces via ion adsorption. Notably, treatment with K3PO4 solutions significantly enhances permselectivity, resulting in a giant output power density of 20.22 W m-2, a 3.6-fold increase over the untreated membrane, setting a benchmark for converting low-grade heat into electrical energy.

14.
Nat Commun ; 15(1): 6837, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122706

RESUMO

Membrane reactors are known for their efficiency and superior operability compared to traditional batch processes, but their limited diversity poses challenges in meeting various reaction requirements. Herein, we leverage the molecular tunability of covalent organic frameworks (COFs) to broaden their applicability in membrane reactors. Our COF membrane demonstrates an exceptional ability to achieve complete conversion in just 0.63 s at room temperature-a benchmark in efficiency for Knoevenagel condensation. This performance significantly surpasses that of the corresponding homogeneous catalyst and COF powder by factors of 176 and 375 in turnover frequency, respectively. The enhanced concentration of reactants and the rapid removal of generated water within the membrane greatly accelerate the reaction, reducing the apparent activation energy. Consequently, this membrane reactor enables reactions that are unattainable using both COF powders and homogeneous catalysts. Considering the versatility, our findings highlight the substantial promise of COF-based membrane reactors in organic transformations.

15.
Plant Physiol ; 158(4): 2028-41, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22291202

RESUMO

We report here that disruption of function of the ω-3 FATTY ACID DESATURASE7 (FAD7) enhances plant defenses against aphids. The suppressor of prosystemin-mediated responses2 (spr2) mutation in tomato (Solanum lycopersicum), which eliminates the function of FAD7, reduces the settling behavior, survival, and fecundity of the potato aphid (Macrosiphum euphorbiae). Likewise, the antisense suppression of LeFAD7 expression in wild-type tomato plants reduces aphid infestations. Aphid resistance in the spr2 mutant is associated with enhanced levels of salicylic acid (SA) and mRNA encoding the pathogenesis-related protein P4. Introduction of the Naphthalene/salicylate hydroxylase transgene, which suppresses SA accumulation, restores wild-type levels of aphid susceptibility to spr2. Resistance in spr2 is also lost when we utilize virus-induced gene silencing to suppress the expression of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1), a positive regulator of many SA-dependent defenses. These results indicate that FAD7 suppresses defenses against aphids that are mediated through SA and NPR1. Although loss of function of FAD7 also inhibits the synthesis of jasmonate (JA), the effects of this desaturase on aphid resistance are not dependent on JA; other mutants impaired in JA synthesis (acx1) or perception (jai1-1) show wild-type levels of aphid susceptibility, and spr2 retains aphid resistance when treated with methyl jasmonate. Thus, FAD7 may influence JA-dependent defenses against chewing insects and SA-dependent defenses against aphids through independent effects on JA synthesis and SA signaling. The Arabidopsis (Arabidopsis thaliana) mutants Atfad7-2 and Atfad7-1fad8 also show enhanced resistance to the green peach aphid (Myzus persicae) compared with wild-type controls, indicating that FAD7 influences plant-aphid interactions in at least two plant families.


Assuntos
Afídeos/fisiologia , Resistência à Doença/efeitos dos fármacos , Ácidos Graxos Dessaturases/metabolismo , Doenças das Plantas/parasitologia , Ácido Salicílico/farmacologia , Solanum lycopersicum/enzimologia , Solanum lycopersicum/imunologia , Acetatos/farmacologia , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/enzimologia , Arabidopsis/imunologia , Arabidopsis/parasitologia , Vias Biossintéticas/efeitos dos fármacos , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Solanum lycopersicum/genética , Solanum lycopersicum/parasitologia , Mutação/genética , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Análise de Sobrevida , Transgenes/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
16.
Physiol Plant ; 149(4): 474-86, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23489195

RESUMO

NAC (NAM-ATAF1, 2-CUC2) family members play important roles in various environmental responses. Here, we cloned a full-length NAC gene (954 bp) from Solanum lycopersicum (SlNAC1). This gene belonged to ATAF subfamily which included ATAF1 and ATAF2 of Arabidopsis thaliana. SlNAC1 expression was induced by chilling stress (4°C), heat stress (40°C), high salinity, osmotic stress and mechanical wounding. SlNAC1 transcripts were enhanced after application of abscisic acid, methyl jasmonate, salicylic acid, gibberellin, ethylene, methyl viologen and hydrogen peroxide. The seedlings of transgenic plants overexpressing SlNAC1 grew more leaves but were shorter than wild-type (WT) plants. SlNAC1 overexpression increased the chilling tolerance of tomato plants by maintaining the higher maximal photochemical efficiency of photosystem II and oxygen-evolving activities. Compared with WT plants, transgenic plants showed higher superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6) activities, which reduced levels of H2 O2 and superoxide anion radicals and promoted lower ion leakage and malondialdehyde content. The expression level of SlCBF1 in transgenic plants was also higher than that in WT plants under both normal conditions and chilling stress; this increased expression may be the main factor influencing the high chilling tolerance of transgenic plants. The results suggest that SlNAC1 plays important roles in diversiform plant-stress responses and diverse signaling pathways.


Assuntos
Arabidopsis/fisiologia , Oxigênio/metabolismo , Solanum lycopersicum/genética , Fatores de Transcrição/metabolismo , Adaptação Fisiológica , Arabidopsis/genética , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/enzimologia , Solanum lycopersicum/fisiologia , Complexo de Proteína do Fotossistema II/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico , Fatores de Transcrição/genética
17.
Zhonghua Yi Xue Za Zhi ; 93(41): 3284-7, 2013 Nov 05.
Artigo em Zh | MEDLINE | ID: mdl-24401624

RESUMO

OBJECTIVE: To prospectively explore the techniques, feasibility and safety of modified vaginal hysterectomy for large uterus. METHODS: A total of 158 patients undergoing hysterectomy at Beijing Hospital from January 2008 to December 2010 were divided into three groups: 12-16 gestational weeks large uterus for vaginal hysterectomy (n = 65, group 1), 12-16 gestational weeks uterus for abdominal hysterectomy (n = 47, group 2) and <10 gestational weeks uterus for vaginal hysterectomy (n = 46, group 3). The pattern and techniques of delivery in group 1 was based on the location of fibroids/adenomyoma (in anterior wall, posterior wall, uterine horn or broad ligament, cervix) and the direction of overall shape maximum diameter (direction towards abdomen defined as long type while the direction towards lateral pelvic wall wide type). The completion and safety were observed intraoperatively. The outpatient follow-up period was 1 month. RESULTS: A total of 158 cases of hysterectomy were performed successfully. The locations of fibroids/adenomyoma included anterior wall (n = 17), posterior wall (n = 24), unilateral uterine horn (n = 6), broad ligament (n = 3) and cervix (n = 2). in group 1, and there were long (n = 6) and wide (n = 7) types. They were all successfully delivered through vagina through various techniques. No case was converted into laparotomy. The average largest size (judged by as large as number of gestational weeks) and weight of uterus was group 2 and followed by group 1. But the difference of size and weight between two groups was insignificant (P > 0.05). Sorted by mean operative duration, mean amount of bleeding and decrease of hemoglobin, the declining order was the group 2, group 1 and group 3. The amount of bleeding for group 1 was less than that for group 2 (P < 0.05). But it was more than group 3 (P > 0.05). According to postoperative hospitalization duration, flatus time and indwelling catheter time, no statistical differences existed between groups 1 and 3. But the values of group 1 were significantly better than those of group 2 (P < 0.01, <0.05, <0.01). CONCLUSION: Vaginal hysterectomy is a safe and effective option for removing enlarged uterus. This pattern of operation can reduce the postoperative hospitalization time, flatus time and indwelling catheter time.


Assuntos
Histerectomia Vaginal/métodos , Doenças Uterinas/cirurgia , Útero , Feminino , Humanos , Tamanho do Órgão , Estudos Prospectivos
18.
Artigo em Inglês | MEDLINE | ID: mdl-36749691

RESUMO

The demand to improve the chlorine resistance of polyamide (PA) membranes is escalated with greater amounts of chlorine-containing disinfectant being used in global water treatment during the COVID-19 pandemic. In this work, we designed thiophene-functionalized poly(ethyleneimine) (TPEI) materials first and grafted them onto a conventional PA membrane to develop novel nanofiltration membranes (PEI-M, TPEI-1-M, TPEI-2-M). These membranes have dual-functionalized selective surfaces covered by hydrophilic amino groups and electron-rich thiophene moieties, which endow these membranes with superior chlorine resistance and improved separation performance. The modified membranes increase the rejection of MgCl2 from 86.5% of the nascent PA membrane (PA-M) to higher than 93.0% without sacrificing the membrane water permeability. More stable separation performance is achieved with all of the as-prepared membranes than PA-M after exposure to a 2000 ppm sodium hypochlorite solution. TPEI-2-M outperforms other membranes after being treated in a chlorination intensity of 16,000 ppm·h with the smallest flux loss and the highest MgCl2 rejection. This is mainly ascribed to the highest amount of amino and thiophene moieties on the TPEI-2-M surface. This study provides an effective protocol for developing novel PA-based nanofiltration membranes while demonstrating its superiority over current technologies with exceptional separation performance and antichlorine ability.

19.
JACS Au ; 3(8): 2166-2173, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37654585

RESUMO

Numerous chemical transformations require two or more catalytically active sites that act in a concerted manner; nevertheless, designing heterogeneous catalysts with such multiple functionalities remains an overwhelming challenge. Herein, it is shown that by the integration of acidic flexible polymers and Pd-metallated covalent organic framework (COF) hosts, the merits of both catalytically active sites can be utilized to realize heterogeneous synergistic catalysis that are active in the conversion of nitrobenzenes to carbamates via reductive carbonylation. The concentrated catalytically active species in the nanospace force two catalytic components into proximity, thereby enhancing the cooperativity between the acidic species and Pd species to facilitate synergistic catalysis. The resulting host-guest assemblies constitute more efficient systems than the corresponding physical mixtures and the homogeneous counterparts. Furthermore, this system enables easy access to a family of important derivatives such as herbicides and polyurethane monomers and can be integrated with other COFs, showing promising results. This study utilizes host-guest assembly as a versatile tool for the fabrication of multifunctional catalysts with enhanced cooperativity between different catalytic species.

20.
Clin Nutr ; 42(10): 1932-1939, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37634307

RESUMO

BACKGROUND: Postoperative skeletal muscle loss (SM loss) was reported to be associated with a poor prognosis in early-stage non-small cell lung cancer (NSCLC). Small airway dysfunction (SAD) is a common but neglected respiratory abnormality. Little information is known about the association between preoperative SAD and postoperative SM loss in early-stage NSCLC. Therefore, this study aimed to investigate the correlation between preoperative SAD and SM loss after surgery in early-stage NSCLC patients. METHODS: There were 348 NSCLC patients with stages I-IIIA in this study from January 2017 to December 2020. All CT images were contrast-enhanced scans, and the skeletal muscle index (SMI) was measured using CT images. A 10.0% decrease in SMI over 12 months was determined as the cut-off value to define excessive SM loss. Logistic regression analyses were used to examine the relationship between SAD and SM loss. RESULTS: This study included 348 subjects who underwent pulmonary operation (159 males and 189 females; mean age: 57.5 ± 8.8 years). 152 (43.7%) patients were identified as having SAD before surgery, and 179 patients (51.4%) were identified as having SM loss after 1 year. Moreover, a higher incidence of SAD was found in the SM loss group compared with that in the non-SM loss group (52.0% vs. 34.9%, p = 0.001). The patients with SAD were older, had larger tumor size, and had lower albumin levels. Furthermore, there were significant correlations between the lung function parameters manifesting SAD and the percentage change in SMI (for the forced expiratory flow when 75% of forced vital capacity has been exhaled (FEF75%), Pearson r=-0.107, p = 0.046; for FEF50%, r = -0.142, p = 0.008; and for FEF25-75%, r=-0.124, p = 0.021; respectively). However, no significant correlations were found between SMI and the lung function parameters reflecting proximal airway obstruction (p > 0.05). Logistic regression analysis revealed that preoperative SAD (HR, 2.465; 95% CI, 1.256-4.838; p = 0.009) was independent risk factor for postoperative SM loss in early-stage NSCLC. In addition, multivariable analysis revealed that SAD (HR, 1.816; 95% CI, 1.025-3.216, P = 0.041) were associated with postoperative complications. CONCLUSION: Preoperative SAD is significantly associated with postoperative complications and SM loss in early NSCLC patients. Our results suggest that preoperative assessment of SAD may be useful for risk stratification of surgical candidates with potential for targeted interventions.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Prognóstico , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos
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