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1.
Proc Natl Acad Sci U S A ; 121(29): e2323040121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985761

RESUMO

Stomata in leaves regulate gas (carbon dioxide and water vapor) exchange and water transpiration between plants and the atmosphere. SLow Anion Channel 1 (SLAC1) mediates anion efflux from guard cells and plays a crucial role in controlling stomatal aperture. It serves as a central hub for multiple signaling pathways in response to environmental stimuli, with its activity regulated through phosphorylation via various plant protein kinases. However, the molecular mechanism underlying SLAC1 phosphoactivation has remained elusive. Through a combination of protein sequence analyses, AlphaFold-based modeling and electrophysiological studies, we unveiled that the highly conserved motifs on the N- and C-terminal segments of SLAC1 form a cytosolic regulatory domain (CRD) that interacts with the transmembrane domain(TMD), thereby maintaining the channel in an autoinhibited state. Mutations in these conserved motifs destabilize the CRD, releasing autoinhibition in SLAC1 and enabling its transition into an activated state. Our further studies demonstrated that SLAC1 activation undergoes an autoinhibition-release process and subsequent structural changes in the pore helices. These findings provide mechanistic insights into the activation mechanism of SLAC1 and shed light on understanding how SLAC1 controls stomatal closure in response to environmental stimuli.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Estômatos de Plantas , Transdução de Sinais , Fosforilação , Estômatos de Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Domínios Proteicos , Mutação
2.
Nano Lett ; 24(15): 4649-4657, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38572971

RESUMO

Deep-seated bacterial infections (DBIs) are stubborn and deeply penetrate tissues. Eliminating deep-seated bacteria and promoting tissue regeneration remain great challenges. Here, a novel radical-containing hydrogel (SFT-B Gel) cross-linked by a chaotropic effect was designed for the sensing of DBIs and near-infrared photothermal therapy (NIR-II PTT). A silk fibroin solution stained with 4,4',4″-(1,3,5-triazine-2,4,6-triyl)tris(1-methylpyridin-1-ium) (TPT3+) was employed as the backbone, which could be cross-linked by a closo-dodecaborate cluster (B12H122-) through a chaotropic effect to form the SFT-B Gel. More interestingly, the SFT-B Gel exhibited the ability to sense DBIs, which could generate a TPT2+• radical with obvious color changes in the presence of bacteria. The radical-containing SFT-B Gel (SFT-B★ Gel) possessed strong NIR-II absorption and a remarkable photothermal effect, thus demonstrating excellent NIR-II PTT antibacterial activity for the treatment of DBIs. This work provides a new approach for the construction of intelligent hydrogels with unique properties using a chaotropic effect.


Assuntos
Fototerapia , Terapia Fototérmica , Hidrogéis/farmacologia
3.
Biomacromolecules ; 25(6): 3554-3565, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729918

RESUMO

Hydrogels are considered as a potential cartilage replacement material based on their structure being similar to natural cartilage, which are of great significance in repairing cartilage defects. However, it is difficult for the existing hydrogels to combine the high load bearing and low friction properties (37 °C) of cartilage through sample methods. Herein, we report a facile and new fabrication strategy to construct the PNIPAm/EYL hydrogel by using the macrophase separation of supersaturated N-isopropylacrylamide (NIPAm) monomer solution to promote the formation of liposomes from egg yolk lecithin (EYL) and asymmetric template method. The PNIPAm/EYL hydrogels possess a relatively high compressive strength (more than 12 MPa), fracture energy (9820 J/m2), good fatigue resistance, lubricating properties, and excellent biocompatibility. Compared with the PNIPAm hydrogel, the friction coefficient (COF 0.046) of PNIPAm/EYL hydrogel is reduced by 50%. More importantly, the COF (0.056) of PNIPAm/EYL hydrogel above lower critical solution temperature (LCST) does not increase significantly, exhibiting heat-tolerant lubricity. The finite element analysis further proves that PNIPAm/EYL hydrogel can effectively disperse the applied stress and dissipate energy under load conditions. This work not only provides new insights for the design of high-strength lubricating hydrogels but also lays a foundation for the treatment of cartilage injury as a substitute material.


Assuntos
Resinas Acrílicas , Hidrogéis , Hidrogéis/química , Resinas Acrílicas/química , Animais , Temperatura Alta , Lubrificantes/química , Cartilagem/química , Lecitinas/química , Força Compressiva , Lipossomos/química , Gema de Ovo/química , Materiais Biocompatíveis/química
4.
Inorg Chem ; 63(6): 3075-3082, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38295520

RESUMO

Herein, an unprecedented cadmium-based metal-organic framework (JNU-106) fabricated by utilizing pyrazole-functionalized tetraphenylethylene ligands (Py-TPE) and rod-shaped secondary building units is reported, possessing a new (3,3,3,6,6,8)-connected topological network. Thanks to the ingeniously designed intramolecular charge transfer behavior, which originates from the congruent coplanarity between Py and TPE, JNU-106 exhibits intense green luminescence with a quantum yield increased by 1.5 times. The phenomenon of remarkable fluorescence quenching of JNU-106 reveals that it possesses extremely high anti-interference performance, superior sensitivity, and dedicated selectivity toward tetracycline antibiotics (TCAs) in aqueous solutions, which are comparable to those of the state-of-the-art porous sensing compounds. Taking the theoretical calculations and experimental results into account, the luminescence quenching is mainly attributed to the internal filtration effect and the static quenching effect. Considering the portable and rapid performance of JNU-106-based testing strips for sensing TCAs, the fabricated JNU-106 provides an alternative for ecological monitoring and environmental governance.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38551441

RESUMO

Objective: This study examines the dynamic changes of stress hormones, including insulin (INS), fasting blood glucose (FBG), glucagon (Glu), and cortisol (Cort), in trauma patients. By monitoring these changes and observing acute pressure injury (API) occurrences on the skin, the research analyzes the influence of stress hormones on API development in trauma patients. Methods: A prospective analysis involved 218 trauma patients admitted to a grade III-A general hospital in Wenzhou from April 2021 to June 2023. Among them, 44 cases developed API (API group), and 174 cases did not (control group). Levels of INS, Cort, Glu, and FBG were measured in both groups. Additionally, Abbreviated Injury Scale-Injury Severity Score (AIS-ISS) surveys and API severity assessments were conducted. Correlations between stress hormone levels and AIS-ISS were discussed. The predictive effects of AIS-ISS and stress hormones on API occurrence in trauma patients were analyzed using receiver operating characteristic (ROC) curves. The relationship between stress hormone levels and API severity was also observed. Results: Study's outcomes indicated distinct relationships between stress hormone levels and API occurrence in trauma patients. Specifically, INS demonstrated a negative correlation with AIS-ISS, highlighting its potential as a significant factor. Glu, Cort, and FBG revealed positive associations, emphasizing their roles in influencing API development (P < .05). The diagnostic efficacy of stress hormones in predicting API occurrence, as represented by the Area Under Curve (AUC) = 0.8100. Notably, within the API group, INS levels demonstrated a decline with worsening API. Conversely, Glu, Cort, and FBG exhibited increases in tandem with the aggravation of API symptoms (P < .05). Conclusions: This research suggests that assessing stress hormone levels in clinical settings can effectively predict API occurrence. Early testing could aid in the development of preventive or intervention measures, reducing the incidence and harm of API in trauma patients.

6.
Chem Biodivers ; 21(7): e202400832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38712949

RESUMO

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.


Assuntos
Antibacterianos , Chaetomium , Testes de Sensibilidade Microbiana , Poríferos , Chaetomium/química , Animais , Poríferos/microbiologia , Poríferos/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Citocalasinas/farmacologia , Citocalasinas/química , Citocalasinas/isolamento & purificação , Conformação Molecular
7.
J Wound Care ; 33(Sup2a): x-xiii, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38324424

RESUMO

Treatment of soft tissue wounds with bone or tendon exposure remains a tough clinical challenge for surgeons. The current clinical approaches include various types of flap reconstruction and artificial dermis grafting as well as negative pressure wound therapy (NPWT), which are time-consuming and often result in graft failure or significant scarring. Concentrated growth factor (CGF) is a novel blood extract that contains many growth factors, platelets and fibrin to promote an orderly healing process. However, few reports have focused on wounds with bone or tendon exposure. We present a limited series and two specific cases of skin wound with bone or tendon exposed that received surgical debridement followed by CGF treatment. CGF appeared to facilitate wound closure effectively and also reduced scar formation. Our findings provide a novel therapeutic option for refractory wounds with bone or tendon exposure.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Lesões dos Tecidos Moles , Humanos , Transplante de Pele , Cicatrização , Lesões dos Tecidos Moles/terapia , Cicatriz/cirurgia , Tendões/cirurgia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Resultado do Tratamento
8.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945154

RESUMO

A new steroid, 2a-oxa-2-oxo-5ß-hydroxy-3,4-dinor-24-methylcholesta-22E-ene (1), together with 10 known ones (2-11), was isolated from the marine sponge Cliona sp. The structures of these compounds were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compound 1 was the third example of 3,4-dinorsteroid with a hemiketal at C-5 that was isolated from the natural source. In addition, the antibacterial activities of these compounds were also evaluated. However, none of them exhibited significant inhibition effects.

9.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257331

RESUMO

Liver fibrosis is the initial pathological process of many chronic liver diseases. Targeting hepatic stellate cell (HSC) activation is an available strategy for the therapy of liver fibrosis. We aimed to explore the anti-liver fibrosis activity and potential mechanism of phomopsterone B (PB) in human HSCs. The results showed that PB effectively attenuated the proliferation of TGF-ß1-stimulated LX-2 cells in a concentration-dependent manner at doses of 1, 2, and 4 µM. Quantitative real-time PCR and Western blot assays displayed that PB significantly reduced the expression levels of α-SMA and collagen I/III. AO/EB and Hoechst33342 staining and flow cytometry assays exhibited that PB promoted the cells' apoptosis. Meanwhile, PB diminished the number of autophagic vesicles and vacuolated structures, and the LC3B fluorescent spots indicated that PB could effectively inhibit the accretion of autophagosomes in LX-2 cells. Moreover, rapamycin and MHY1485 were utilized to further investigate the effect of mTOR in autophagy and apoptosis. The results demonstrated that PB regulated autophagy and apoptosis via the mTOR-dependent pathway in LX-2 cells. In summary, this is the first evidence that PB effectively alleviates liver fibrosis in TGF-ß1-stimulated LX-2 cells, and PB may be a promising candidate for the prevention of liver fibrosis.


Assuntos
Autofagia , Fator de Crescimento Transformador beta1 , Humanos , Cirrose Hepática/tratamento farmacológico , Autofagossomos , Apoptose
10.
Zhonghua Nan Ke Xue ; 30(3): 254-260, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-39177393

RESUMO

Gossypol is a natural product extracted from cotton seeds, roots and stems, once used as a male contraceptive and later found with an anti-tumor effect. Recent studies show that it has an antiviral effect after structurally modified. This review focuses on the status quo of present studies on the effects of gossypol and its derivatives in anti-reproduction and anti-PCa, with an introduction of the application of the new compounds obtained from structural modification of gossypol in the treatment of PCa.


Assuntos
Anticoncepcionais Masculinos , Gossipol , Gossipol/farmacologia , Gossipol/análogos & derivados , Masculino , Humanos , Anticoncepcionais Masculinos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Reprodução/efeitos dos fármacos , Animais
11.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3432-3440, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041115

RESUMO

Molecular pharmacognosy as an emerging interdisciplinary subject based on molecular biology and Chinese materia medica aims to study the synthesis and molecular regulation of secondary metabolites in medicinal plants. Andrographis Herba, the dried aboveground part of Andrographis paniculata, has liver-protecting, bile secretion-promoting, heat-clearing, toxin-removing, antimicrobial, and anti-inflammatory effects. The quality instability caused by plant varieties, environment, and technology in the production of A. paniculata is a limiting factor for the sustainable development of this industry. Based on the research methods of molecular pharmacognosy and omics, the regulation of secondary metabolites of A. paniculata has become the key solution to the quality problems of A. paniculata. This paper summarized the recent research achievements in the molecular pharmacognosy of A. paniculata, including molecular identification of the resources, genetic diversity, multi-omics, biosynthesis of active compounds, and germplasm resource innovation, and prospected the future development trend in this field. In-depth research of molecular pharmacognosy of A. paniculata will provide more scientific and effective technical support for the development of its medicinal value, give new insights into the cultivation of new A. paniculata varieties, and promote the high-quality sustainable development of this industry.


Assuntos
Farmacognosia , Andrographis/química , Andrographis/genética , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/genética , Plantas Medicinais/química , Andrographis paniculata/genética , Andrographis paniculata/química , Andrographis paniculata/metabolismo
12.
Zhongguo Zhong Yao Za Zhi ; 49(2): 379-388, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403314

RESUMO

Andrographis paniculata is an important medicinal plant in the Lingnan region of China, which has the functions of clearing heat, removing toxins, and resisting bacteria and inflammation. The TCP gene family is a class of transcription factors that regulate plant growth, development, and stress response. In order to analysis the role of the TCP gene family under abiotic stress in A. paniculata, this study identified the TCP gene family of A. paniculata at the genome-wide level and analyzed its expression pattern in response to abiotic stress. The results showed that the A. paniculata TCP gene family had 23 members, with length of amino acid ranging from 136 to 508, the relative molecular mass between 14 854.71 and 55 944.90 kDa, and the isoelectric point between 5.67 and 10.39. All members were located in the nucleus and unevenly distributed on 13 chromosomes. Phylogenetic analysis classified them into three subfamilies: PCF, CIN and CYC/TB1. Gene structure and conserved motif analysis showed that most members of the TCP gene family contained motif 1, motif 2, motif 3 in the same order and 1-3 CDS. The analysis of promoter cis-acting elements showed that the transcriptional expression of the TCP gene family in A. paniculata might be induced by light, hormones, and adversity stress. In light of the expression pattern analysis and qRT-PCR verification, the expression of ApTCP4, ApTCP5, ApTCP6, and ApTCP11 involved in response by various abiotic stresses such as drought, high temperature, and MeJA. This study lays the foundation for in-depth exploration of the functions of A. paniculata TCP genes in response to abiotic stress.


Assuntos
Aminoácidos , Andrographis paniculata , Filogenia , China , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética
13.
Environ Sci Pollut Res Int ; 31(12): 18448-18464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38347352

RESUMO

The digital economy is playing a crucial effect in the field of environmental governance. Digital and intelligent management is an essential means to fully realize the "zero-waste city" construction. The present paper investigates the impact of digital economy on China's provincial "zero-waste city" construction. The results indicate that digital economy can contribute to "zero-waste city" construction. The digital economy has a positive nonlinear effect on the construction of "zero-waste city," but the marginal effect is diminishing. The digital economy can facilitate "zero-waste city" construction by improving industrial structure upgrading and green technology innovation. Heterogeneity analysis reveals that digital economy contributes to the construction of "zero-waste city" in the eastern and western regions and high-level environmental regulation regions, while this impact is insignificant in the central region and low-level environmental regulation regions. The digital economy exerts the most significant positive influence on waste resource recycling followed by waste final disposal and then waste reduction at the source. These findings underscore the effect of digital economy in fostering "zero-waste city" construction and promoting sustainable waste management. The present study provides new ideas for the "zero-waste city" construction in emerging developing countries such as China.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , China , Indústrias , Reciclagem , Desenvolvimento Econômico , Cidades
14.
World J Gastroenterol ; 30(9): 999-1004, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38577181

RESUMO

The albumin-bilirubin (ALBI) score, which was proposed to assess the prognosis of patients with hepatocellular carcinoma, has gradually been extended to other liver diseases in recent years, including primary biliary cholangitis, liver cirrhosis, hepatitis, liver transplantation, and liver injury. The ALBI score is often compared with classical scores such as the Child-Pugh and model for end-stage liver disease scores or other noninvasive prediction models. It is widely employed because of its immunity to subjective evaluation indicators and ease of obtaining detection indicators. An increasing number of studies have confirmed that it is highly accurate for assessing the prognosis of patients with chronic liver disease; additionally, it has demonstrated good predictive performance for outcomes beyond survival in patients with liver diseases, such as decompensation events. This article presents a review of the application of ALBI scores in various non-malignant liver diseases.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Terminal , Neoplasias Hepáticas , Humanos , Bilirrubina , Albumina Sérica , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/cirurgia , Estudos Retrospectivos , Índice de Gravidade de Doença , Carcinoma Hepatocelular/patologia , Prognóstico , Neoplasias Hepáticas/patologia
15.
Plant Physiol Biochem ; 208: 108481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447424

RESUMO

Gravitropism is a vital mechanism through which plants adapt to their environment. Previous studies indicated that Ca2+ may play an important role in plant gravitropism. However, our understanding of the calcium signals in root gravitropism is still largely limited. Using a vertical stage confocal and transgenic Arabidopsis R-GECO1, our data showed that gravity stimulation enhances the occurrence of calcium spikes and increases the Ca2+ concentration in the lower side of the root cap. Furthermore, a close correlation was observed in the asymmetry of calcium signals with the inclination angles at which the roots were oriented. The frequency of calcium spikes on the lower side of 90°-rotated root decreases rapidly over time, whereas the asymmetric distribution of auxin readily strengthens for up to 3 h, indicating that the calcium spikes, promoted by gravity stimulation, may precede auxin as one of the early signals. In addition, the root gravitropism of starchless mutants is severely impaired. Correspondingly, no significant increase in calcium spike occurrence was observed in the root caps of these mutants within 15 min following a 90° rotation, indicating the involvement of starch grains in the formation of calcium spikes. However, between 30 and 45 min after a 90° rotation, asymmetric calcium spikes were indeed observed in the root of starchless mutants, suggesting that starch grains are not indispensable for the formation of calcium spikes. Besides, co-localization analysis suggests that the ER may function as calcium stores during the occurrence of calcium spikes. These findings provide further insights into plant gravitropism.


Assuntos
Arabidopsis , Gravitropismo , Cálcio , Raízes de Plantas/fisiologia , Arabidopsis/fisiologia , Ácidos Indolacéticos , Plantas , Amido
16.
Sci Rep ; 14(1): 6504, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499622

RESUMO

This study aimed to investigate the role of autophagy, ferroptosis, and pyroptosis in the antitumour mechanism of harmine (Har) and its crosstalk in ovarian cancer. By transmission electron microscopy, we found that compared with those in the control group, the cytoplasm of human ovarian cancer cells (SKOV3) treated with Har showed increased numbers of autophagic vesicles, decreased intracellular mitochondrial volume, increased bilayer membrane density, and decreased cristae. Western blot, immunofluorescence, and monodasylcadaverine (MDC) staining all suggested that Har promoted autophagy in SKOV3 cells. LY294002 and siFOXO3 rescued the inhibition of the PI3K/AKT/mTOR/FOXO3 signalling pathway and the promotion of autophagy by Har. Additionally, the levels of ferroptosis- and pyroptosis-related proteins and the levels of Fe2+ , glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) suggested that Har promoted ferroptosis and pyroptosis in SKOV3 cells. Interestingly, pretreatment with chloroquine (CQ), erastin, rapamycin (Rap), or ferrostatin-1 (Fer-1) increased or reversed the ferroptosis and pyroptosis promoted by Har, respectively. In vivo, the volume of tumours in the Har group was decreased, and immunohistochemistry revealed decreased levels of Ki-67 and GPX4 and increased levels of ATG5 and NARL3. In conclusion, Har exerts its anti-ovarian cancer effect not only by promoting autophagy by regulating the PI3K/AKT/mTOR/FOXO3 signalling pathway but also by promoting ferroptosis and pyroptosis. Additionally, there is complex crosstalk between autophagy, ferroptosis, and pyroptosis in ovarian cancer.


Assuntos
Ferroptose , Neoplasias Ovarianas , Feminino , Humanos , Piroptose , Harmina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Autofagia
17.
Nat Prod Res ; : 1-6, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591101

RESUMO

A chemical investigation on the marine sponge Dysidea sp. resulted in the isolation of a series of diketopiperazines, including two new compounds, dysidines A (1) and B (2) as well as six known ones (3-8). Their structures with absolute configurations were determined on the basis of UV, IR, HRMS, NMR and calculated ECD method. Additionally, the cytotoxic, anti-inflammatory, antibacterial and antiviral activities of 1-8 were also tested. However, none of them exhibited significant bioactivities.

18.
Heliyon ; 10(10): e31036, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38774323

RESUMO

Objectives: This study aims to investigate the use of sodium iodide (NaI), dimethyl sulfoxide (DMSO), ethyl alcohol, and ethyl acetate as cone-beam CT (CBCT) contrast agents for diagnosing cracked teeth. The optimal delay time for detecting the number of crack lines beyond the dentino-enamel junction (Nd), the number of cracks extending from the occlusal surface to the pulp cavity (Np), and the depth of the crack lines was explored. Methods: 14 human extracted cracked teeth were collected, 12 were used for enhanced scanning, and 2 were used for exploring the characteristic of crack lines. The teeth were scanned in 3 CBCT enhanced scanning (ES) modes: ES1 using meglumine diatrizoate (MD); ES2 using NaI and DMSO, ES3 using NaI, DMSO, ethyl alcohol and ethyl acetate. Three delay times (15mins, 30mins, and 60mins) were set for scanning. Nd, Np, and depth of crack lines were evaluated. Results: There were totally 24 crack lines on 12 cracked teeth. Nd was 10 in ES1 at 60mins, 24 in ES2 at 60mins and 24 in ES3 at 15mins. Np was 1 in ES1 at 60mins, 10 in ES2 at 60mins and 21 in ES3 at 60mins, and there were significantly different among them (p < 0.01). The average depth presented on ES3 was significantly deeper than ES1 and ES2 (p < 0.01). Conclusion: NaI, DMSO, ethyl alcohol and ethyl acetate show potential as contrast agents for enhanced CBCT scanning in diagnosis of cracked teeth and their depth in vivo. A delay time of 15 min is necessary to confirm the existence of crack lines, while a longer delay time is required to ascertain if these crack lines extend to the pulp cavity.

19.
Int J Biol Macromol ; 269(Pt 2): 131825, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679271

RESUMO

Flexible electronics are highly developed nowadays in human-machine interfaces (HMI). However, challenges such as lack of flexibility, conductivity, and versatility always greatly hindered flexible electronics applications. In this work, a multifunctional hybrid hydrogel (H-hydrogel) was prepared by combining two kinds of 1D polymer chains (polyacrylamide and polydopamine) and two kinds of 2D nanosheets (Ti3C2Tx MXene and graphene oxide nanosheets) as quadruple crosslinkers. The introduced Ti3C2Tx MXene and graphene oxide nanosheets are bonded with the PAM and PDA polymer chains by hydrogen bonds. This unique crosslinking and stable structure endow the H-hydrogel with advantages such as good flexibility, electrical conductivity, self-adhesion, and mechanical robustness. The two kinds of nanosheets not only improved the mechanical strength and conductivity of the H-hydrogel, but also helped to form the double electric layers (DELs) between the nanosheets and the bulk-free water phase inside the H-hydrogel. When utilized as the electrode of a triboelectric nanogenerator (TENG), high electrical output performances were realized due to the dynamic balance of the DELs between the nanosheets and the H-hydrogel's inside water molecules. Moreover, flexible sensors, including triboelectric, and strain/pressure sensors, were achieved for human motion detection at low frequencies. This hydrogel is promising for HMI and e-skin.


Assuntos
Condutividade Elétrica , Grafite , Hidrogéis , Dispositivos Eletrônicos Vestíveis , Hidrogéis/química , Grafite/química , Humanos , Polímeros/química , Eletrônica , Resinas Acrílicas/química , Titânio/química , Indóis/química
20.
Chem Commun (Camb) ; 60(43): 5606-5609, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38712962

RESUMO

Caged gem-dithiols have been developed as the donors of reactive sulfur species (RSS), but the chemistry of free gem-dithiols as RSS donors has not been well understood. Herein, we report the study of a free gem-dithiol, 1,3-diphenylpropane-2,2-dithiol, as the precursor for several RSS. It releases H2S under physiological conditions and can be converted to a mono-S-nitrosothiol, which serves as a NO donor. Furthermore, it can be converted to 3,3-dibenzyldithiirane, which is an active sulfur transfer reagent and can induce S-persulfidation.

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