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1.
J Hazard Mater ; 479: 135729, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39243547

RESUMO

Vibrio alfacsensis is traditionally seen as an environmental symbiont within its genus, with no detailedly documented pathogenicity in marine aquaculture to date. This study delves into the largely unexplored pathogenic potential and emerging antibiotic resistance of V. alfacsensis. The VA-1 strain, isolated from recirculating aquaculture system (RAS) effluent of cultured turbot (Scophthalmus maximus), underwent comprehensive analysis including biochemical identification, antibiotic susceptibility testing and reinfection trials. The results confirmed VA-1's pathogenicity and significant multiple antibiotic resistance. VA-1 could induce systemic infection in turbot, with symptoms like kidney enlargement, exhibiting virulence comparable to known Vibrio pathogens, with an LD50 around 2.36 × 106 CFU/fish. VA-1's remarkable resistance phenotype (14/22) suggested potential for genetic exchange and resistance factor acquisition in aquaculture environments. Phylogenetic analysis based on 16S rDNA sequences and whole-genome sequencing has firmly placed VA-1 within the V. alfacsensis clade, while genome-wide analysis highlights its similarity and diversity in relation to strains from across the globe. VA-1 contained numerous replicons, indicating the possibility for the spread of resistance and virulence genes. This study suggests V. alfacsensis may acquire and transfer pathogenic and resistant traits through horizontal gene transfer, a likelihood intensified by changing environmental and aquaculture conditions, highlighting the need for vigilant pathogen monitoring and new non-antibiotic treatments.


Assuntos
Antibacterianos , Aquicultura , Farmacorresistência Bacteriana Múltipla , Doenças dos Peixes , Linguados , Vibrio , Animais , Linguados/microbiologia , Vibrio/efeitos dos fármacos , Vibrio/genética , Vibrio/patogenicidade , Doenças dos Peixes/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Antibacterianos/farmacologia , Vibrioses/microbiologia , Vibrioses/veterinária , Filogenia , Virulência , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética
2.
Front Microbiol ; 15: 1366336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113837

RESUMO

Streptomycetes are well-known antibiotic producers possessing in their genomes numerous silent biosynthetic pathways that might direct the biosynthesis of novel bio-active specialized metabolites. It is thus of great interest to find ways to enhance the expression of these pathways to discover most needed novel antibiotics. In this study, we demonstrated that the over-expression of acetyltransferase SCO0988 up-regulated the production of specialized metabolites and accelerated sporulation of the weak antibiotic producer, Streptomyces lividans and that the deletion of this gene had opposite effects in the strong antibiotic producer, Streptomyces coelicolor. The comparative analysis of the acetylome of a S. lividans strain over-expressing sco0988 with that of the original strain revealed that SCO0988 acetylates a broad range of proteins of various pathways including BldKB/SCO5113, the extracellular solute-binding protein of an ABC-transporter involved in the up-take of a signal oligopeptide of the quorum sensing pathway. The up-take of this oligopeptide triggers the "bald cascade" that regulates positively specialized metabolism, aerial mycelium formation and sporulation in S. coelicolor. Interestingly, BldKB/SCO5113 was over-acetylated on four Lysine residues, including Lys425, upon SCO0988 over-expression. The bald phenotype of a bldKB mutant could be complemented by native bldKB but not by variant of bldKB in which the Lys425 was replaced by arginine, an amino acid that could not be acetylated or by glutamine, an amino acid that is expected to mimic acetylated lysine. Our study demonstrated that Lys425 was a critical residue for BldKB function but was inconclusive concerning the impact of acetylation of Lys425 on BldKB function.

3.
Chem Sci ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39129778

RESUMO

Single cell amperometry has proven to be a powerful and well-established method for characterizing single vesicular exocytotic events elicited at the level of excitable cells under various experimental conditions. Nevertheless, most of the reported characteristics are descriptive, being mostly concerned with the morphological characteristics of the recorded current spikes (maximum current intensities, released charge, rise and fall times, etc.) which are certainly important but do not provide sufficient kinetic information on exocytotic mechanisms due to lack of quantitative models. Here, continuing our previous efforts to provide rigorous models rationalizing the kinetic structures of frequently encountered spike types (spikes with unique exponential decay tails and kiss-and-run events), we describe a new theoretical approach enabling a quantitative kinetic modeling of all types of exocytotic events giving rise to current spikes exhibiting exponential decay tails. This model follows directly from the fact that the condensation of long intravesicular polyelectrolytic strands by high concentrations of monocationic neurotransmitter molecules leads to a matrix structure involving two compartments in constant kinetic exchanges during release. This kinetic model has been validated theoretically (direct and inverse problems) and its experimental interest established by the analysis of the amperometric spikes relative to chromaffin and PC12 cells previously published by some of us.

4.
Microorganisms ; 12(8)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39203389

RESUMO

Exploring the response of the diversity of phytoplankton species and functional groups to environmental variables is extremely important in maintaining biodiversity in aquatic ecosystems. Although there were more taxonomic units at the species level than at the functional group level, it remained unclear whether species diversity was more sensitive than functional group diversity to environmental variables. In this study, taxonomic composition and alpha-beta diversity of phytoplankton were investigated in 23 subtropical reservoirs located in the Han River Basin in South China during wet and dry seasons. Structural Equation Modelling (SEM) and Generalized Dissimilarity Modelling (GDM) were employed to validate the response of phytoplankton species and functional group alpha-beta diversities to environmental variables. The results indicated that the community compositions of phytoplankton in eutrophic reservoirs were similar between wet and dry seasons, while there were distinct differences for community composition in oligotrophic-mesotrophic reservoirs between the two seasons. Across all reservoirs, there were no significant differences in alpha and beta diversities of species and functional groups between wet and dry seasons. The SEM and GDM results revealed that total phosphorus was the primary driving factor influencing alpha and beta diversities of species and functional groups in the 23 reservoirs. Meanwhile, the non-linear results of species beta diversity were stronger than the non-linear results of functional group beta diversity, indicating that phytoplankton species exhibited a higher explanatory power in responding to environmental changes compared to that of functional groups. Compared to that of species beta diversity, the response of functional group beta diversity to environmental variables was significantly lower in the dry season. These research findings lead to re-evaluating the common practice relating to the use of phytoplankton functional groups to assess environmental conditions, which may overlook the explanatory power of subtle changes at the species level, especially during periods of habitat diversification in the dry season.

5.
ACS Chem Biol ; 19(8): 1674-1682, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39041925

RESUMO

Rhomboid proteases have fascinated scientists by virtue of their membrane-embedded active sites and proposed involvement in physiological and disease pathways. The human rhomboid protease RHBDL4 has generated particular interest due to its role in endoplasmic reticulum-associated protein degradation and upregulation in several cancers; however, chemical tools for studying this enzyme are currently lacking. Here, we describe the development of an activity-based protein profiling (ABPP) assay for RHBDL4. We have employed this assay to determine that human RHBDL4 undergoes proteolytic processing in cells to produce multiple active proteoforms with truncated C-termini. We have also used this assay to identify chemical scaffolds capable of inhibiting RHBDL4 activity and have observed distinct inhibitor preferences between RHBDL4 and a second human rhomboid protease PARL. Our work demonstrates the power of ABPP technology to characterize active forms of enzymes that might otherwise elude detection and the potential to achieve selective inhibition among the human rhomboid proteases.


Assuntos
Proteólise , Humanos , Proteólise/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Endopeptidases/metabolismo , Células HEK293
6.
PLoS One ; 19(4): e0300655, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626178

RESUMO

Ports are critical centers of international trade and global logistics now that economic globalization has taken hold. The efficiency performance of port logistics is crucial to building an emerging pattern of development in which domestic and foreign dual cycles are complementary for China. This paper examines the efficiency performance of 19 ports within five major economic circles in China. It explores how their efficiency is distributed, and the configurations of efficiency improvement during the new normal of China's economy. First, the DEA-BCC model is employed to calculate the technical efficiency performance and distribution of each port from 2011 to 2020. Then, fuzzy-set qualitative comparative analysis (fsQCA) was applied to integrate and analyze the influencing factors. The results show as follows: (1) Each port group performed differently on efficiency rankings, as well as regional distributions. Among these, the port groups of the Bohai Rim region, the Yangtze River Delta region, and the Bohai Rim region continue to rank highly. (2) From the perspective of configuration analysis, the results suggest that government support is not necessary for port logistics with better economic endowments. However, it is critical for backward ones. (3) A rational industrial structure can enhance levels of infrastructure, openness, and information technology, improving port performance. The findings can provide theoretical and practical references for better promoting the development of Chinese port management.al references for better promoting the development of Chinese port management.


Assuntos
Comércio , Internacionalidade , Eficiência , Indústrias , China , Desenvolvimento Econômico
7.
Updates Surg ; 76(4): 1521-1527, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38438686

RESUMO

With the emergence of novel variants, Omicron variant caused a different clinical picture than the previous variants and little evidence was reported regarding perioperative outcomes after Omicron variants. The aim of the study was to evaluate the postoperative outcomes of gastrointestinal cancer patients following Omicron variants infection and also to determine the timing of surgery after infection recovery. A total of 124 patients who underwent gastrointestinal cancer surgery with prior SARS-CoV-2 infection between December 2022 and February 2023 were retrospectively reviewed. 174 cases underwent the same operation during December 2018 and February 2019 as control group. SARS-CoV-2-infected patients were further categorized into three groups based on infected time (1-3 weeks; 4-6 weeks; and ≥ 7 weeks). 90.3% of SARS-CoV-2-infected patients had mild symptoms. The COVID-19 vaccination rate was 71.0%, with a full vaccination rate of 48.4%. There were no significant differences in 30-day morbidity and mortality. There was also no significant difference in pulmonary complications, cardiovascular complications, and surgical complications between the three different diagnosis time groups. In conclusion, reducing waiting time for elective surgery was safe for gastrointestinal cancer patients in the context of an increased transmissibility and milder illness severity with Omicron variant.


Assuntos
COVID-19 , Procedimentos Cirúrgicos Eletivos , Neoplasias Gastrointestinais , Complicações Pós-Operatórias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Neoplasias Gastrointestinais/cirurgia , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/epidemiologia , Fatores de Tempo , Vacinas contra COVID-19 , Adulto
8.
Environ Toxicol ; 39(5): 2908-2926, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38299230

RESUMO

BACKGROUND: Colorectal cancer (CRC) presents a significant global health burden, characterized by a heterogeneous molecular landscape and various genetic and epigenetic alterations. Programmed cell death (PCD) plays a critical role in CRC, offering potential targets for therapy by regulating cell elimination processes that can suppress tumor growth or trigger cancer cell resistance. Understanding the complex interplay between PCD mechanisms and CRC pathogenesis is crucial. This study aims to construct a PCD-related prognostic signature in CRC using machine learning integration, enhancing the precision of CRC prognosis prediction. METHOD: We retrieved expression data and clinical information from the Cancer Genome Atlas and Gene Expression Omnibus (GEO) datasets. Fifteen forms of PCD were identified, and corresponding gene sets were compiled. Machine learning algorithms, including Lasso, Ridge, Enet, StepCox, survivalSVM, CoxBoost, SuperPC, plsRcox, random survival forest (RSF), and gradient boosting machine, were integrated for model construction. The models were validated using six GEO datasets, and the programmed cell death score (PCDS) was established. Further, the model's effectiveness was compared with 109 transcriptome-based CRC prognostic models. RESULT: Our integrated model successfully identified differentially expressed PCD-related genes and stratified CRC samples into four subtypes with distinct prognostic implications. The optimal combination of machine learning models, RSF + Ridge, showed superior performance compared with traditional methods. The PCDS effectively stratified patients into high-risk and low-risk groups, with significant survival differences. Further analysis revealed the prognostic relevance of immune cell types and pathways associated with CRC subtypes. The model also identified hub genes and drug sensitivities relevant to CRC prognosis. CONCLUSION: The current study highlights the potential of integrating machine learning models to enhance the prediction of CRC prognosis. The developed prognostic signature, which is related to PCD, holds promise for personalized and effective therapeutic interventions in CRC.


Assuntos
Apoptose , Neoplasias Colorretais , Humanos , Prognóstico , Aprendizado de Máquina , Neoplasias Colorretais/genética
9.
Plant Mol Biol ; 114(2): 20, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363403

RESUMO

SQUAMOSA PROMOTER BINDING PROTEIN-LIKEs (SPLs) encode plant-specific transcription factors that regulate plant growth and development, stress response, and metabolite accumulation. However, there is limited information on Scutellaria baicalensis SPLs. In this study, 14 SbSPLs were identified and divided into 8 groups based on phylogenetic relationships. SbSPLs in the same group had similar structures. Abscisic acid-responsive (ABRE) and MYB binding site (MBS) cis-acting elements were found in the promoters of 8 and 6 SbSPLs. Segmental duplications and transposable duplications were the main causes of SbSPL expansion. Expression analysis based on transcriptional profiling showed that SbSPL1, SbSPL10, and SbSPL13 were highly expressed in roots, stems, and flowers, respectively. Expression analysis based on quantitative real-time polymerase chain reaction (RT‒qPCR) showed that most SbSPLs responded to low temperature, drought, abscisic acid (ABA) and salicylic acid (SA), among which the expression levels of SbSPL7/9/10/12 were significantly upregulated in response to abiotic stress. These results indicate that SbSPLs are involved in the growth, development and stress response of S. baicalensis. In addition, 8 Sba-miR156/157 s were identified, and SbSPL1-5 was a potential target of Sba-miR156/157 s. The results of target gene prediction and coexpression analysis together indicated that SbSPLs may be involved in the regulation of L-phenylalanine (L-Phe), lignin and jasmonic acid (JA) biosynthesis. In summary, the identification and characterization of the SbSPL gene family lays the foundation for functional research and provides a reference for improved breeding of S. baicalensis stress resistance and quality traits.


Assuntos
Ácido Abscísico , Scutellaria baicalensis , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Scutellaria baicalensis/genética , Scutellaria baicalensis/metabolismo , Filogenia , Melhoramento Vegetal , Estresse Fisiológico/genética , Hormônios/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
10.
Sci Total Environ ; 915: 170037, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232856

RESUMO

Large missing sources of daytime atmospheric nitrous acid (HONO), a vital source of hydroxyl radicals (OH) through its photolysis, frequently exist in global coastal regions. In this study, ambient HONO and relevant species were measured at a coastal site in the Pearl River Delta (PRD), China, during October 2019. Relatively high concentrations (0.32 ± 0.19 ppbv) and daytime peaks at approximately 13:00 of HONO were observed, and HONO photolysis was found to be the dominant (55.5 %) source of the primary OH production. A budget analysis of HONO based on traditional sources suggested large unknown sources during the daytime (66.4 %), which had a significant correlation with the mass of coarse particles (PM2.5-10) and photolysis frequency (J(NO2)). When incorporating photolysis of the abundant nitrate measured in coarse particles with a reasonable enhancement factor relative to fine particles due to favorable aerosol conditions, the missing daytime sources of HONO could be fully compensated by coarse particles serving as the largest source at this coastal site. Our study revealed great potential of coarse particles as a strong daytime HONO source, which has been ignored before but can efficiently promote NOx recycling and thus significantly enhance atmospheric oxidation capacity.

11.
PhytoKeys ; 237: 79-89, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38282985

RESUMO

Aletrisguangxiensis Y. Nong & Y. F. Huang (Nartheciaceae), a new species from Guangxi, China, is described and illustrated. This new species is most similar to A.scopulorum, but it can be easily distinguished by its sparsely glandular, 5-18 cm long scape, glandular inflorescence axis, distinctly pedicellate flowers, sparsely glandular, 5-10 mm long pedicel, bract borne at base of pedicel, glabrous perianth divided to the base, strongly recurved or revolute perianth lobes and turbinate, obovoid to oblong-obovoid capsule. An identification key for 24 species and 1 hybrid of Aletris is also provided.

12.
Sensors (Basel) ; 23(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38139669

RESUMO

Rolling bearings are a key component for ensuring the safe and smooth operation of rotating machinery and are very prone to failure. Therefore, intelligent fault diagnosis research on rolling bearings has become a crucial task in the field of mechanical fault diagnosis. This paper proposes research on the fault diagnosis of rolling bearings based on an adaptive nearest neighbor strategy and the discriminative fusion of multi-feature information using supervised manifold learning (AN-MFIDFS-Isomap). Firstly, an adaptive nearest neighbor strategy is proposed using the Euclidean distance and cosine similarity to optimize the selection of neighboring points. Secondly, three feature space transformation and feature information extraction methods are proposed, among which an innovative exponential linear kernel function is introduced to provide new feature information descriptions for the data, enhancing feature sensitivity. Finally, under the adaptive nearest neighbor strategy, a novel AN-MFIDFS-Isomap algorithm is proposed for rolling bearing fault diagnosis by fusing various feature information and classifiers through discriminative fusion with label information. The proposed AN-MFIDFS-Isomap algorithm is validated on the CWRU open dataset and our experimental dataset. The experiments show that the proposed method outperforms other traditional manifold learning methods in terms of data clustering and fault diagnosis.

13.
PhytoKeys ; 234: 219-227, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927972

RESUMO

Walsuraguangxiensis (Meliaceae), a new species from Guangxi, China, is here described and illustrated. The new species is easily distinguishable from the other two Chinese members of the genus by its petals being pale yellow, filaments being connate into tubes above the middle, the berry being oval and glabrous. An identification key of Walsura for 17 species is also provided.

14.
PhytoKeys ; 235: 189-198, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020467

RESUMO

Lysimachiacavicola (Subgen. Idiophyton, Primulaceae), a new species from Guangxi, China, is here described and illustrated based on morphological data. Although it shares similarities with L.microcarpa, L.fooningensis, and L.capillipes, there are distinguishing characteristics that set it apart. These include erect stems either solitary or in clusters of 1 to 2, herbaceous, terete, and densely glandular hairy. The leaves are either ovate or elliptical lanceolate, with inconspicuously reticulate veins. The petiole measures 2-4 mm in length covered with minute glandular hairy. The corolla is deeply parted, measuring 6-8 mm in length, with narrowly elliptic or narrowly oblong lobes that are 1-2 mm wide. The capsule is globose, measuring 2-3 × 2-3 mm, and possesses a chalky, brittle texture, which splits into 5-valved segments. The calyx of the plant appears yellowish-white during fruiting. This newly discovered species is endemic to limestone areas in Fengshan County, Guangxi, China.

15.
Cell Chem Biol ; 30(12): 1542-1556.e9, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37714153

RESUMO

Identification of cysteines with high oxidation susceptibility is important for understanding redox-mediated biological processes. In this report, we report a chemical proteomic strategy that finds cysteines with high susceptibility to S-glutathionylation. Our proteomic strategy, named clickable glutathione-based isotope-coded affinity tag (G-ICAT), identified 1,518 glutathionylated cysteines while determining their relative levels of glutathionylated and reduced forms upon adding hydrogen peroxide. Among identified cysteines, we demonstrated that CTNND1 (p120) C692 has high susceptibility to glutathionylation. Also, p120 wild type (WT), compared to C692S, induces its dissociation from E-cadherin under oxidative stress, such as glucose depletion. p120 and E-cadherin dissociation correlated with E-cadherin destabilization via its proteasomal degradation. Lastly, we showed that p120 WT, compared to C692S, increases migration and invasion of MCF7 cells under glucose depletion, supporting a model that p120 C692 glutathionylation increases cell migration and invasion by destabilization of E-cadherin, a core player in cell-cell adhesion.


Assuntos
Cateninas , delta Catenina , Humanos , Cateninas/metabolismo , Proteômica , Caderinas/metabolismo , Movimento Celular , Glucose
16.
J Infect Chemother ; 29(12): 1145-1151, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37611744

RESUMO

INTRODUCTION: Klebsiella pneumoniae is one of the common pathogenic bacteria that can cause infections in hospitals and communities and can cause respiratory, urinary, and other multi-system infections. In recent years, the emergence of highly virulent and drug-resistant Klebsiella pneumoniae has greatly increased the difficulty of treatment for infection. Clinically, it is very important to accurately judge the virulence of isolated Klebsiella pneumoniae for treatment, but there is no better method to evaluate its virulence. METHODS: In this study, zebrafish were used as a model organism, and the swimming distance was used as a detection index to identify clinically isolated Klebsiella pneumoniae. In this study, we selected two different strains of Klebsiella pneumoniae, i.e., NTUH-K2044 and ATCC BAA-1705, with known high and low virulence, respectively, to infect zebrafish juveniles and evaluated their behavioral ability according to different bacterial concentrations and different developmental times. RESULTS: It was found that highly virulent Klebsiella pneumoniae caused a significant decrease in the behavioral ability of zebrafish larvae, while low-virulence Klebsiella pneumoniae had relatively little effect. CONCLUSIONS: These results indicate that it is entirely feasible to assess the virulence of Klebsiella pneumoniae based on behavioral ability.

17.
Surg Laparosc Endosc Percutan Tech ; 33(4): 431-434, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37311036

RESUMO

BACKGROUND: Better exposition is important for lymph node dissection in the suprapancreatic region and lesser curvature region of the stomach, and digestive tract reconstruction, especially without excellent assistants. PATIENTS AND METHODS: We developed a new laparoscopic retraction method with the use of two internal retractors (TIRs) punctured along with suture. Clinicopathological data, surgical data, and postoperative outcomes were assessed. RESULTS: Of the 143 patients included, 51 underwent surgery with the double-sling suture method and 92 underwent surgery with the TIRs method. Laparoscopic radical gastrectomy was successfully performed in all patients. There were no significant differences in patient characteristics or preoperative data in the 2 groups. The operative time was significantly shorter in the TIR group, but the amount of bleeding did not differ. No retraction-related complications both in clipped tissue and liver occurred in all patients. CONCLUSIONS: Our new retraction technique provided an optimal surgical field and make surgery lower requirements for assistants.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Laparoscopia/métodos , Excisão de Linfonodo/métodos , Fígado/cirurgia , Gastrectomia/métodos , Estudos Retrospectivos
18.
Chem Sci ; 14(18): 4905-4912, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37181786

RESUMO

The detailed structure of the water layer in the inner Helmholtz plane of a solid/aqueous solution interface is closely related to the electrochemical and catalytic performances of electrode materials. While the applied potential can have a great impact, specifically adsorbed species can also influence the interfacial water structure. With the specific adsorption of p-nitrobenzoic acid on the Au(111) surface, a protruding band above 3600 cm-1 appears in the electrochemical infrared spectra, indicating a distinct interfacial water structure as compared to that on bare metal surfaces, which displays a potential-dependent broad band in the range of 3400-3500 cm-1. Although three possible structures have been guessed for this protruding infrared band, the band assignment and interfacial water structure remain ambiguous in the past two decades. Herein, by combining surface-enhanced infrared absorption spectroscopy and our newly developed quantitative computational method for electrochemical infrared spectra, the protruding infrared band is clearly assigned to the surface-enhanced stretching mode of water molecules hydrogen-bonded to the adsorbed p-nitrobenzoate ions. Water molecules, meanwhile, are hydrogen-bonded with themselves to form chains of five-membered rings. Based on the reaction free energy diagram, we further demonstrate that both hydrogen-bonding interactions and coverages of specifically adsorbed p-nitrobenzoate play an important role in determining the structure of the water layer in the Au(111)/p-nitrobenzoic acid solution interface. Our work sheds light on structural studies of the inner Helmholtz plane under specific adsorptions, which advances the understanding of structure-property relationships in electrochemical and heterogeneous catalytic systems.

19.
Can J Gastroenterol Hepatol ; 2023: 6351330, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090103

RESUMO

Purpose: Our objective was to compare the value of positron emission tomography/magnetic resonance imaging (PET/MRI) with the new imaging agent [68Ga]Ga-DOTA-FAPI-04 and the traditional imaging agent [18F]FDG for the preoperative diagnosis of gastric cancer. Methods: Forty patients with gastric cancer diagnosed by gastroscopy in gastrointestinal surgery at our hospital from June 2020 to January 2021 were analyzed. All patients underwent simultaneous [68Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/MRI. The standard uptake value (SUV), fat removal standard uptake value (SUL), and diagnostic sensitivity, specificity, and accuracy for primary and metastatic lesions were compared, and their diagnostic value for different lymph node dissection stages was analyzed. Results: The median age of the patients in this cohort was 68 years. Twenty-nine patients underwent surgery, and 11 patients underwent gastroscopic biopsy. The SUVmax of primary lesions in the FDG group and the FAPI group was 5.74 ± 5.09 and 8.06 ± 4.88, respectively (P < 0.01); SULmax values were 3.52 ± 2.80 and 5.64 ± 3.25, respectively (P < 0.01). The SUVmax of metastases in the two groups was 3.81 ± 3.08 and 5.17 ± 2.80, respectively (P < 0.05). The diagnostic sensitivities for primary lesions in the FDG group and the FAPI group were 0.72 and 0.94, respectively (P < 0.05). Combined with postoperative pathological staging, there was no difference in diagnostic sensitivity and specificity of lymph node staging between the FDG and FAPI groups (P > 0.05). Conclusion: Compared with the traditional imaging agent, [68Ga]Ga-DOTA-FAPI-04 has better diagnostic efficiency but no substantial advantage for preoperative lymph node staging.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Gástricas , Humanos , Idoso , Radioisótopos de Gálio , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
20.
Bioact Mater ; 27: 15-57, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37035422

RESUMO

Titanium (Ti) and its alloys have been widely used as orthopedic implants, because of their favorable mechanical properties, corrosion resistance and biocompatibility. Despite their significant success in various clinical applications, the probability of failure, degradation and revision is undesirably high, especially for the patients with low bone density, insufficient quantity of bone or osteoporosis, which renders the studies on surface modification of Ti still active to further improve clinical results. It is discerned that surface physicochemical properties directly influence and even control the dynamic interaction that subsequently determines the success or rejection of orthopedic implants. Therefore, it is crucial to endow bulk materials with specific surface properties of high bioactivity that can be performed by surface modification to realize the osseointegration. This article first reviews surface characteristics of Ti materials and various conventional surface modification techniques involving mechanical, physical and chemical treatments based on the formation mechanism of the modified coatings. Such conventional methods are able to improve bioactivity of Ti implants, but the surfaces with static state cannot respond to the dynamic biological cascades from the living cells and tissues. Hence, beyond traditional static design, dynamic responsive avenues are then emerging. The dynamic stimuli sources for surface functionalization can originate from environmental triggers or physiological triggers. In short, this review surveys recent developments in the surface engineering of Ti materials, with a specific emphasis on advances in static to dynamic functionality, which provides perspectives for improving bioactivity and biocompatibility of Ti implants.

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