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1.
Molecules ; 29(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38675532

RESUMO

Pyxinol, an active metabolite of ginsenosides in human hepatocytes, exhibits various pharmacological activities. Here, a series of C-3 modified pyxinol derivatives was designed and virtually screened by molecular docking with the key inflammation-related proteins of the nuclear factor kappa B (NF-κB) pathway. Some of the novel derivatives were synthesized to assess their effects in inhibiting the production of nitric oxide (NO) and mitochondrial reactive oxygen species (MtROS) in lipopolysaccharide-triggered RAW264.7 cells. Derivative 2c exhibited the highest NO and MtROS inhibitory activities with low cytotoxicity. Furthermore, 2c decreased the protein levels of interleukin 1ß, tumor necrosis factor α, inducible nitric oxide synthase, and cyclooxygenase 2 and suppressed the activation of NF-κB signaling. Cellular thermal shift assays indicated that 2c could directly bind with p65 and p50 in situ. Molecular docking revealed that 2c's binding to the p65-p50 heterodimer and p50 homodimer was close to their DNA binding sites. In summary, pyxinol derivatives possess potential for development as NF-κB inhibitors.


Assuntos
Anti-Inflamatórios , Simulação de Acoplamento Molecular , NF-kappa B , Óxido Nítrico , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Camundongos , Animais , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Humanos , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Relação Estrutura-Atividade
2.
Angew Chem Int Ed Engl ; : e202405846, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871656

RESUMO

Understanding the diverse electrochemical reactions occurring at electrode-electrolyte interfaces (EEIs) is a critical challenge to developing more efficient energy conversion and storage technologies. Establishing a predictive molecular-level understanding of solid electrolyte interphases (SEIs) is challenging due to the presence of multiple intertwined chemical and electrochemical processes occurring at battery electrodes. Similarly, chemical conversions in reactive electrochemical systems are often influenced by the heterogeneous distribution of active sites, surface defects, and catalyst particle sizes. In this mini review, we highlight an emerging field of interfacial science that isolates the impact of specific chemical species by preparing precisely-defined EEIs and visualizing the reactivity of their individual components using single-entity characterization techniques. We highlight the broad applicability and versatility of these methods, along with current state-of-the-art instrumentation and future opportunities for these approaches to address key scientific challenges related to batteries, chemical separations, and fuel cells. We establish that controlled preparation of well-defined electrodes combined with single entity characterization will be crucial to filling key knowledge gaps and advancing the theories used to describe and predict chemical and physical processes occurring at EEIs and accelerating new materials discovery for energy applications.

3.
Angew Chem Int Ed Engl ; : e202406407, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862386

RESUMO

The design of admire hydrogel networks is of both practical and fundamental importance for diverse applications of hydrogels. Herein a general strategy of acid-assisted training is designed to enable multiple improvement of conventional poly (sodium acrylate) networks for hydrogels. Hydrophobic homogeneous crosslinked poly (sodium acrylate) hydrogels are prepared to verify the strategy. The acid-assisted training is simply achieved by immersing the hydrogel networks into 4 M H2SO4 solutions. The introduced acids would induce transformation of poly (sodium acrylate) into poly (acrylic acid) at hydrogel surface, which constructs dynamic hydrogen bonding interactions to tighten the network. The acid-containing poly (sodium acrylate) hydrogels newly generate anti-swelling and self-healing performance, and show mechanical improvement. The internal poly (sodium acrylate) of the pristine acid-containing hydrogels is further fully transformed via acid-infiltration after following cyclic stretch/release training to significantly improve the mechanical performance. The Young's modulus, stress, and toughness of the fully-trained hydrogels are 187.6 times, 35.6 times, and 5.4 times enhanced, respectively. The polymeric networks retain isotropic in fully-trained hydrogels to ensure superior stretchability of 8.6. The acid-assisted training performance of the hydrogels can be reversibly recovered by NaOH neutralization. The acid-assisted training strategy here is general for poly (sodium acrylate) hydrogels.

4.
Small ; : e2310186, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059820

RESUMO

Developing electrolytes combining solid-like instinct stability and liquid-like conducting performance will be satisfactory for efficient and durable Li-ion batteries. Herein lamellar lyotropic liquid crystals (LLCs) demonstrate high-voltage windows, efficient charge transport, and inherent thermal safety as solid-state electrolytes in lithium-ion batteries. Lamellar LLCs are simply prepared by nanosegregation of [C16 Mim][BF4 ] and LiBF4 /Propylene carbonate (PC) liquid solutions, which induce lamellar assembly of the liquids as dynamic conducting pathways. Broadened liquid conducting pathways will boost the conducting performance of the LLC electrolytes. The lyotropic lamellar nanostructures enable liquid-like ion conductivity of the LLC electrolytes at ambient temperatures, as well as provide solid-like stability for the electrolytes to resist high voltage and flammability overwhelming to LiBF4 /PC liquid electrolytes. Despite minor consumption of PC solvents (34.5 wt.%), the lamellar electrolytes show energy conversion efficiency comparable to the liquid electrolytes (PC wt. 92.8%) in Li/LiFePO4 batteries under ambient temperatures even at a 2 C current density, and exhibit attractively robust stability after 200th cyclic charge/discharge even under 60 °C. The work demonstrates LLC electrolytes have great potential to supersede traditional liquid electrolytes for efficient and durable Lithium-ion (Li-ion) batteries.

5.
Opt Express ; 31(18): 29491-29503, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710748

RESUMO

We demonstrate a scheme to realize high-efficiency entanglement of two microwave fields in a dual opto-magnomechanical system. The magnon mode simultaneously couples with the microwave cavity mode and phonon mode via magnetic dipole interaction and magnetostrictive interaction, respectively. Meanwhile, the phonon mode couples with the optical cavity mode via radiation pressure. Each magnon mode and optical cavity mode adopts a strong red detuning driving field to activate the beam splitter interaction. Therefore, the entangled state generated by the injected two-mode squeezed light in optical cavities can be eventually transferred into two microwave cavities. A stationary entanglement E a 1 a 2 =0.54 is obtained when the input two-mode squeezed optical field has a squeezing parameter r = 1. The entanglement E a 1 a 2 increases as the squeezing parameter r increases, and it shows the flexible tunability of the system. Meanwhile, the entanglement survives up to an environmental temperature about 385 mK, which shows high robustness of the scheme. The proposed scheme provides a new mechanism to generate entangled microwave fields via magnons, which enables the degree of the prepared microwave entanglement to a more massive scale. Our result is useful for applications which require high entanglement of microwave fields like quantum radar, quantum navigation, quantum teleportation, quantum wireless fidelity (Wi-Fi) network, etc.

6.
Soft Matter ; 19(2): 268-275, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36514910

RESUMO

Acid hydrogels comprising polymer networks are promising soft electrolytes whose proton conductivities are most often regulated by acid content. Herein, promotion of conductivity by solely regulating polymer morphology has been demonstrated for acid hydrogels with identical acid content. Polymerization of acrylamide at different temperatures in the same aqueous solution, which is a lyotropic liquid crystal (LLC) of 4-(1-ethyldecyl)benzenesulfonic acid (EDBSA) exhibiting a phase transition at 30 °C, affords acid hydrogels comprising ordered and random polymer networks. The ordered polymer network templated by the lamellar liquid crystal at 15 °C possesses more interconnected and extended pores than that obtained in the isotropic solution at 45 °C. Electrochemical characterization shows that the ordered network affords 48% higher proton conductivity than the random network for hydrogels holding the EDBSA LLC. This higher conductivity is ascribed to more numerous long-range transport pathways formed in larger pores and fewer barriers in the network for protons to pass through. Enhanced conductivities are also obtained from the ordered polymer network for hydrogels comprising micellar EDBSA solution and H2SO4 solution, albeit to lesser degrees. These results shed light on the dependence of electrochemical performance on the polymer morphology of hydrogels and offer a strategy to enhance the conductivity of hydrogels without changing their polymer fraction.

7.
Org Biomol Chem ; 21(33): 6783-6788, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37565619

RESUMO

Salicylic acid (SA) is a key hormone that regulates plant growth and immunity, and understanding the physiologic processes induced by SA enables the development of highly pathogen-resistant crops. Here, we report the synthesis of three new SA-sensors (R1-R3) from hydroxyphenol derivatives of a rhodamine-acylhydrazone scaffold and their characterization by NMR and HRMS. Spectroscopic analyses revealed that structural variations in R1-R3 resulted in sensors with different sensitivities for SA. Sensor R2 (with the 3-hydroxyphenyl modification) outperformed R1 (2-hydroxyphenyl) and R3 (4-hydroxyphenyl). The SA-detection limit of R2 is 0.9 µM with an ultra-fast response time (<60 s). In addition, their plant imaging indicated that designed sensor R2 is useful for the further study of SA biology and the discovery and development of new inducers of plant immunity.


Assuntos
Células Vegetais , Ácido Salicílico , Rodaminas/química , Ácido Salicílico/análise , Ácido Salicílico/química , Células Vegetais/química , Corantes , Plantas
8.
Bioorg Chem ; 134: 106467, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36933337

RESUMO

Ginsenosides are a promising group of secondary metabolites for developing anti-inflammatory agents. In this study, Michael acceptor was fused into the aglycone A-ring of protopanoxadiol (PPD)-type ginsenosides (MAAG), the main pharmacophore of ginseng, and its liver metabolites to produce novel derivatives and assess their anti-inflammatory activity in vitro. The structure-activity relationship of MAAG derivatives was assessed based on their NO-inhibition activities. Of these, a 4-nitrobenzylidene derivative of PPD (2a) was the most effective and dose-dependently inhibited the release of proinflammatory cytokines. Further studies indicated that 2a-induced downregulation on lipopolysaccharide (LPS)-induced iNOS protein expression and cytokine release may be related to its inhibitory effect on MAPK and NF-κB signaling pathways. Importantly, 2a almost completely inhibited LPS-induced production of mitochondrial reactive oxygen species (mtROS) and LPS-induced NLRP3 upregulation. This inhibition was higher than that by hydrocortisone sodium succinate, a glucocorticoid drug. Overall, the fusion of Michael acceptors into the aglycone of ginsenosides greatly enhanced the anti-inflammatory activities of the derivatives, and 2a alleviated inflammation considerably. These findings could be attributed to the inhibition of LPS-induced mtROS to block abnormal activation of the NLRP3 pathway.


Assuntos
Ginsenosídeos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ginsenosídeos/farmacologia , Ginsenosídeos/metabolismo , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Transdução de Sinais , Citocinas/metabolismo
9.
Cell Mol Life Sci ; 79(5): 247, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35437611

RESUMO

BACKGROUND AND AIM: Platelets are an able regulator of CD4+ T cell immunity. Herein, the mechanisms underlying platelet-regulated effector responses of naïve CD4+ T (Tn) cells were investigated. METHODS: Platelet-Tn cell co-cultures of human cells, genetically modified murine models, and high-throughput bioinformatic analyses were combined to elucidate molecular mechanisms of platelet-dependent regulation. RESULTS: Platelets exerted sophisticated regulation on effector responses of type 1, 2, and 17 T helper (Th1/Th2/Th17) and regulatory T (Treg) cells, in time-, concentration-, and organ-dependent manners and with close cooperation of transforming growth factor ß (TGFß) and platelet factor 4 (PF4). PF4 at low concentrations reinforced TGFß signaling by heteromerizing with type III TGFß receptor (TGFBRIII), and subsequently enhanced TGFBRII expression and TGFß signaling. High-concentration PF4 had, however, opposite effects by directly binding to TGFBRII, blocking TGFß-TGFBRII ligation, and thus inhibiting TGFß signaling. Furthermore, platelet depletion markedly hampered Treg and Th17 responses in the spleen but not in the lymph nodes, blockade of platelet-Tn cell contact diminished platelet effects, while spleen injection of PF4-immobilized microparticles in PF4-deficient mice mimicked platelet effects, suggesting the importance of direct platelet-Tn contact and platelet-bound PF4 for the optimal regulatory effects by platelets. CONCLUSION: Platelets exert context-dependent regulations on effector responses of Tn cells via PF4-TGFß duet, suggesting new possibilities of platelet-targeted interventions of T cell immunity.


Assuntos
Fator Plaquetário 4 , Fator de Crescimento Transformador beta , Animais , Plaquetas/metabolismo , Linfócitos T CD4-Positivos , Camundongos , Fator Plaquetário 4/metabolismo , Linfócitos T Reguladores , Fator de Crescimento Transformador beta/metabolismo
10.
Proc Natl Acad Sci U S A ; 117(12): 6559-6570, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32156735

RESUMO

Secretagogin (SCGN) is a hexa-EF-hand protein that is highly expressed in the pancreas, brain, and gastrointestinal tract. SCGN is known to modulate regulated exocytosis in multiple cell lines and tissues; however, its exact functions and underlying mechanisms remain unclear. Here, we report that SCGN interacts with the plasma membrane SNARE SNAP-25, but not the assembled SNARE complex, in a Ca2+-dependent manner. The crystal structure of SCGN in complex with a SNAP-25 fragment reveals that SNAP-25 adopts a helical structure and binds to EF-hands 5 and 6 of SCGN. SCGN strongly inhibits SNARE-mediated vesicle fusion in vitro by binding to SNAP-25. SCGN promotes the plasma membrane localization of SNAP-25, but not Syntaxin-1a, in SCGN-expressing cells. Finally, SCGN controls neuronal growth and brain development in zebrafish, likely via interacting with SNAP-25 or its close homolog, SNAP-23. Our results thus provide insights into the regulation of SNAREs and suggest that aberrant synapse functions underlie multiple neurological disorders caused by SCGN deficiency.


Assuntos
Exocitose , Secretagoginas/química , Secretagoginas/metabolismo , Animais , Sítios de Ligação , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Cálcio/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Mutação , Ligação Proteica , Conformação Proteica , Secretagoginas/genética , Proteína 25 Associada a Sinaptossoma/genética , Proteína 25 Associada a Sinaptossoma/metabolismo , Peixe-Zebra
11.
Pestic Biochem Physiol ; 191: 105377, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36963945

RESUMO

Insect cytochrome P450 monooxygenases (P450s or CYPs) perform important functions in the metabolic detoxification of both endogenous and exogenous substrates. However, the mechanism of action of the P450 genes in bees is unclear. In this study, we investigated the effects of AccCYP6k1 on the metabolism and detoxification of Apis cerana cerana. Spatiotemporal expression profiling revealed that the expression of AccCYP6k1 was the highest in foragers (A15) and was mainly expressed in the leg, midgut and head. RT-qPCR results showed that AccCYP6k1 exhibited different expression patterns following exposure to xenobiotics. In addition, silencing AccCYP6k1 increased the pesticides sensitivity and affected the detoxification system and antioxidant process of A. cerana cerana. In brief, the induced expression of AccCYP6k1 is related to the resistance of A. cerana cerana, while knockdown AccCYP6k1 affect the pesticides resistance and metabolic detoxification system of A. cerana cerana. These findings not only support the theoretical basis of metabolic detoxification in bees but also provide a better understanding of P450-mediated resistance to pesticides in insects.


Assuntos
Antioxidantes , Praguicidas , Abelhas/genética , Animais , Interferência de RNA , Estresse Oxidativo/genética , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Insetos/genética
12.
Insect Mol Biol ; 31(5): 634-646, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35619242

RESUMO

Cuticular proteins (CPs) are known to play important roles in insect development and defence responses. The loss of CP genes can lead to changes in insect morphology and sensitivity to the external environment. In this study, we identified the AccCPR2 gene, which belongs to the CPR family (including the R&R consensus motif) of CPs, and explored its function in the response of Apis cerana cerana to adverse external stresses. Our results demonstrated that AccCPR2 was highly expressed in the late pupal stage and epidermis, and the expression of AccCPR2 may be induced or inhibited under different stressors. RNA interference experiments showed that knockdown of AccCPR2 reduced the activity of antioxidant enzymes, led to the accumulation of oxidative damage and suppressed the expression of several antioxidant genes. In addition, knockdown of AccCPR2 also reduced the pesticide resistance of A. cerana cerana. The overexpression of AccCPR2 in a prokaryotic system further confirmed its role in resistance to various stresses. In summary, AccCPR2 may play pivotal roles in the normal development and environmental stress response of A. cerana cerana. This study also enriched the theoretical knowledge of the resistance biology of bees.


Assuntos
Antioxidantes , Proteínas de Insetos , Animais , Antioxidantes/metabolismo , Abelhas/genética , Proteínas de Insetos/metabolismo , Estresse Oxidativo , Interferência de RNA , Estresse Fisiológico/genética
13.
Platelets ; 33(3): 360-370, 2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-34137652

RESUMO

Platelets regulate multiple aspects of CD4+ T cell immunity, and may exert distinct regulations among different T cell subsets. Our aim was to investigate how platelets regulate CD4+ central memory T cell (Tcm) responses. αCD3/αCD28-stimulated human CD4+ Tcm cells were cultured without or with platelets or platelet-derived mediators. Polyclonal stimulation induced cell proliferation and Th1 and Treg cell activation of Tcm cells. Platelet factor 4/PF4 neutralization abolished platelet-enhanced Tcm effector responses, whilst TGFß neutralization only partially inhibited platelet-enhanced Treg cell activation. PF4 supplementation mimicked the effects of platelet co-cultures, while PF4 receptor CXCR3 blockade and CXCR3 knockdown with siRNAs inhibited or abolished PF4-enhanced Th1 and Treg cell responses. Platelet co-cultures or PF4-treatment increased Tcm cell proliferation, whilst CXCR3 blockade counteracted. PF4-enhanced Tcm proliferation and effector cell responses were associated with mitochondrial biogenesis. Overexpression of mitochondrial transcription factor A (TFAM) mimicked PF4 effects, and PF4 treatment attenuated Akt phosphorylation of activated Tcm cells, leading to mitochondrial biogenesis. Impacts of platelets and PF4 on Tcm proliferation were further confirmed by that CXCR3 knockdown/blockade counteracted PF4-enhanced Tcm cell proliferation. In conclusion, platelets enhance Th1 and Treg cell responses of CD4+ Tcm cells, via PF4-dependent mitochondrial biogenesis and cell proliferation of Tcm cells.


Assuntos
Plaquetas/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Células T de Memória/metabolismo , Fator Plaquetário 4/imunologia , Adulto , Proliferação de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biogênese de Organelas , Adulto Jovem
14.
J Cell Mol Med ; 25(1): 434-447, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33225628

RESUMO

Alzheimer's disease (AD) is the most common dementia, characterized by pathological accumulation of ß-amyloid (Aß) and hyperphosphorylation of tau protein, together with a damaging chronic inflammation. The lack of effective treatments urgently warrants new therapeutic strategies. Resolution of inflammation, associated with beneficial and regenerative activities, is mediated by specialized pro-resolving lipid mediators (SPMs) including maresin 1 (MaR1). Decreased levels of MaR1 have been observed in AD brains. However, the pro-resolving role of MaR1 in AD has not been fully investigated. In the present study, human monocyte-derived microglia (MdM) and a differentiated human monocyte cell line (THP-1 cells) exposed to Aß were used as models of AD neuroinflammation. We have studied the potential of MaR1 to inhibit pro-inflammatory activation of Aß and assessed its ability to stimulate phagocytosis of Aß42 . MaR1 inhibited the Aß42 -induced increase in cytokine secretion and stimulated the uptake of Aß42 in both MdM and differentiated THP-1 cells. MaR1 was also found to decrease chemokine secretion and reduce the associated increase in the activation marker CD40. Activation of kinases involved in transduction of inflammation was not affected by MaR1, but the activity of nuclear factor (NF)-κB was decreased. Our data show that MaR1 exerts effects that indicate a pro-resolving role in the context of AD and thus presents itself as a potential therapeutic target for AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Microglia/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Western Blotting , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Células Cultivadas , Ácidos Docosa-Hexaenoicos/genética , Humanos , Imuno-Histoquímica , NF-kappa B/metabolismo , Fagocitose/genética , Fagocitose/fisiologia , Células THP-1
15.
Anticancer Drugs ; 32(4): 417-426, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33079732

RESUMO

The epidermal growth factor receptor (EGFR) signaling is frequently activated in lung cancer. In our previous study, a new class of compounds containing pyrido[3,4-d]pyrimidine scaffold with an acrylamide moiety was designed as irreversible EGFR-tyrosine kinase inhibitors to overcome acquired EGFR-T790M resistance. In this study, we selected the most promising compound Z25h to further investigate its effects and the underlying mechanism against non-small cell lung adenocarcinoma cells in vitro. Four different non-small cell lung adenocarcinoma cell lines were selected to test the antiviability profile of Z25h, and Hcc827 was the most sensitive to the drug treatment. Z25h caused cell cycle arrest at G0-G1 phase, and triggered strong early apoptosis in Hcc827 cells at 0.1 µM and late apoptosis in A549, H1975 and H1299 cells at 10 µM by 48 h treatment. Z25h inhibited the activation of EGFR and its downstream PI3K/AKT/mTOR pathway in the four tested cell lines, leading to the inhibition of cellular biosynthetic and metabolic processes and the promotion of apoptotic process. However, the effect of Z25h on mitogen-activated protein kinase pathway varies from cell lines. In addition, Z25h sensitized H1975 cells to X-ray radiation, and it also enhanced the radiation effect on A549 cells, while no obvious effect of Z25h was observed on the cell viability inhibition of H1299 cells induced by radiation. Hereby, Z25h might be considered as a potential therapeutic drug candidate for non-small cell lung adenocarcinoma treatment.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Pirimidinas/farmacologia , Células A549 , Adenocarcinoma de Pulmão/enzimologia , Adenocarcinoma de Pulmão/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia
16.
Macromol Rapid Commun ; 42(16): e2100232, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34121263

RESUMO

Ionic species are important to dominate phase separation behaviors of poly(N-isopropylacrylamide) (PNIPAm) in aqueous solutions. Herein, photoresponsive azobenzene-based salts with various ions are prepared and their photoresponsive ion effects on clouding temperatures (TcpS ) of PNIPAm in aqueous solutions are explored. It is found that, despite of various structures of anions and cations, trans-TcpS under vis light irradiation are always higher than cis-TcpS under UV irradiation. Particularly, Hofmeister effect of anions on TcpS is roughly observed. For example, azobenzene with kosmotropic CO3 2- gives the lowest cis-Tcp while in use of typical chaotropic anions, such as ClO4 - , azobenzene isomerization less affects values of Tcp s. In another hand, azobenzene-based metallic salts containing lithium, sodium, and potassium cations also demonstrate photoresponsive Hofmeister effect. Trans-metallic azobenzene demonstrates a chaotropic effect on Tcp s while UV induces kosmotropic behaviors on TcpS . Additionally, ionic conduction of the solution along with photoresponsive phase separations is also investigated and PNIPAm aggregations induce a sharp reduction of ion conduction during UV light illumination.


Assuntos
Resinas Acrílicas , Sais , Compostos Azo , Cátions
17.
Appl Opt ; 60(23): 6888-6901, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613170

RESUMO

In the process of microchannel plate (MCP) making and physicochemical treatment of a low-light-level (LLL) image intensifier, multifilament fixed pattern noise, also known as structural defects, is one of the most common defects in the anode surface. The appearance of this defect will seriously affect the imaging quality of an image intensifier, so it should be found in time before delivery. The traditional evaluation method of this defect relies on subjective judgment, and the disadvantage is that the division of the dense defect area and the measurement of defect gray difference (GD) are not standardized. To address this problem, an automatic evaluation method of vertex structural defects of an LLL image intensifier based on proposed individual image processing strategies is presented, which provides a digital evaluation scheme for such defects. This method is composed of two parts: quasi-circular defect detection and defect GD calculation. The first part is composed of coarse detection and fine detection. Coarse detection is to scan the anode surface and take the two ends of a pair of adjacent line segments with a large gradient sum and opposite gray change direction as the defect boundaries; fine detection is to establish the image patch from defect boundaries, extract the edge segment from the image patch, and judge whether it conforms to the shape of a circle. In order to substantiate the performance of the quasi-circular defect detection strategy, two relevant techniques are used as comparison. One is based on a Gaussian filter, and the other is based on a fixed-size window template. The comparison results show that our method, to the best of our knowledge, has the best detection performance for vertex structural defects. The second part consists of region of interest (ROI) cropping, secondary defect detection, shortest distance sequence establishment, effective distance extraction, triplet set construction, and triplet GD calculation. First, the location histogram of defects is established to cut ROI; then, the secondary defect detection is performed to extract more vertex structural defects from ROI; after that, the shortest distance sequence of defects is constructed, and the effective distances are extracted by using the structural features of multifilament. Finally, the triplet set is generated according to the effective distance, and the triplet GD is calculated based on the gray information near the triplet baseline. The GD of vertex structural defects corresponds to the maximum GD of triplets. So as to verify the effectiveness of vertex defect GD calculation strategy, several image tubes with different degrees of such defects are used for experiments, and the subjective evaluation method is used as comparison. The experimental results substantiate that this method is superior to the subjective method in locating ROI accurately and calculating defect GD quantitatively. In general, the automatic evaluation method can be regarded as an effective evaluation scheme for vertex structural defects of an LLL image intensifier.

18.
Can J Physiol Pharmacol ; 98(1): 1-5, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518506

RESUMO

This study analyzed risk factors for anxiety and depression in 714 patients who received surgery for endometrial cancer. Our data indicate that the incidence of postoperative anxiety and depression in 714 patients with endometrial cancer was 15.55% and 32.77%, respectively. Univariate and logistic regression analysis showed postoperative pain (odds ratio (OR) = 3.166, P = 0.000) and combined liver disease (OR = 2.318, P = 0.001) were independent risk factors for postoperative anxiety. Additionally, CD4+/CD8+ (OR = 0.513, P = 0.042) and natural killer (NK) cell ratios (OR = 0.692, P = 0.021) were independent protective factors for postoperative anxiety. As for depression, low literacy (OR = 1.943, P = 0.042), postoperative pain (OR = 2.671, P = 0.001), high clinical stage (OR = 3.469, P = 0.009), and combined liver disease (OR = 4.865, P = 0.000) were independent risk factors for postoperative depression. CD4+/CD8+ (OR = 0.628, P = 0.002) and NK cell ratio (OR = 0.710, P = 0.013) were independent protective factors for postoperative depression. In conclusion, patients with endometrial cancer have a higher incidence of postoperative anxiety and depression where postoperative pain, liver disease, and decreased immune function are risk factors for both anxiety and depression in these patients.


Assuntos
Ansiedade/etiologia , Povo Asiático/psicologia , Depressão/etiologia , Neoplasias do Endométrio/psicologia , Neoplasias do Endométrio/cirurgia , Adulto , Idoso , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Fatores de Risco
19.
J Environ Manage ; 255: 109859, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32063319

RESUMO

China's paper industry development is rapid, but the recycling rate of China's waste paper has been low all the time. Meanwhile, material flow analysis can help determine the flow of waste paper, and life cycle assessment (LCA) is the methodological framework for quantifying greenhouse gas emissions. Therefore, present study integrates these two methods into the model construction of China's waste paper recycling decision system. Present study constructs a benchmark model of China's waste paper recycling decision system in 2017, focusing on the impact of nonstandard waste paper recycling on the economic and environmental benefits of China's domestic waste paper recycling system. This model construction is followed by sensitivity analysis of the relevant parameters affecting the efficiency of the waste paper recycling system. Finally, present study forecasts the system's economic benefits and greenhouse gas (GHG) emissions in the context of integrating and regulating nonstandard recycling vendors. The results show that the economic benefit of China's waste paper recycling in 2017 is approximately 458.3 yuan/t and that the GHG emissions are 901.1 kgCO2eq. The standard recovery rate and nonstandard recovery acceptance rate will both have a significant impact on the system's economic benefits and improve the GHG emissions structure. In the context of integrating nonstandard recycling enterprises and individual recycling vendors, the economic benefits will rise to 3312.5 yuan/t in 2030, while GHG emissions will rise to 942.9 kgCO2eq. Present study can play a certain guiding role for policy makers in formulating waste paper recycling industry specifications and formulating relevant policies.


Assuntos
Gases de Efeito Estufa , Reciclagem , China , Efeito Estufa , Indústrias
20.
Soft Matter ; 15(40): 7992-7995, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31502625

RESUMO

Azobenzene based inorganic salts containing lithium, sodium or potassium cations were prepared and the behaviors of reversible light modulated ionic conductivity were observed based on photoisomerizations of azobenzene salts in aqueous solutions. The highest ionic conductivity was observed in the solution of potassium ionized azobenzene, assisted by the unique formation of a network-like aggregated morphology.

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