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1.
Lasers Surg Med ; 56(2): 206-217, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38073098

RESUMO

OBJECTIVES: Raman spectroscopy as a diagnostic tool for biofluid applications is limited by low inelastic scattering contributions compared to the fluorescence background from biomolecules. Surface-enhanced Raman spectroscopy (SERS) can increase Raman scattering signals, thereby offering the potential to reduce imaging times. We aimed to evaluate the enhancement related to the plasmonic effect and quantify the improvements in terms of spectral quality associated with SERS measurements in human saliva. METHODS: Dried human saliva was characterized using spontaneous Raman spectroscopy and SERS. A fabrication protocol was implemented leading to the production of silver (Ag) nanopillar substrates by glancing angle deposition. Two different imaging systems were used to interrogate saliva from 161 healthy donors: a custom single-point macroscopic system and a Raman micro-spectroscopy instrument. Quantitative metrics were established to compare spontaneous RS and SERS measurements: the Raman spectroscopy quality factor (QF), the photonic count rate (PR), the signal-to-background ratio (SBR). RESULTS: SERS measurements acquired with an excitation energy four times smaller than with spontaneous RS resulted in improved QF, PR values an order of magnitude larger and a SBR twice as large. The SERS enhancement reached 100×, depending on which Raman bands were considered. CONCLUSIONS: Single-point measurement of dried saliva with silver nanopillars substrates led to reproducible SERS measurements, paving the way to real-time tools of diagnosis in human biofluids.


Assuntos
Prata , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Prata/análise , Prata/química , Saliva/química
2.
Clin Lab ; 69(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307119

RESUMO

BACKGROUND: Autologous Hematopoietic Stem Cell Transplantation with or without CD34+ selection is being used successfully to treat patients with severe and refractory autoimmune disease. This study describes our experience of CD34+ stem cell mobilization, harvesting and selection in autoimmune patients based on conditions in Vietnam - the developing country. METHODS: Eight autoimmune patients (four patients with Myasthenia Gravis and four patients with Systemic Lupus Erythematosus) underwent PBSC mobilization with granulocyte colony-stimulating factor (G-CSF) and cyclophosphamide. The apheresis was performed on a Terumo BCT Spectra Optia machine. CD34+ hematopoetic stem cells were collected from the leukapheresis by CliniMACS Plus device using CD34 Enrichment KIT. CD34+ cells, T and B lymphocytes were counted on a FACS BD Canto II device. RESULTS: Eight patients (4 MG and 4 SLE) including 5 females and 3 males were involved in this study. The mean age of the patients was 33.13 ± 16.64 years (ranging from 13 to 58 years). The average number of days for mobilization was 7.9 ± 1.6 days, whereas the average number of days for harvesting was 1.5 ± 0.5 days. There was no difference in the number of days for mobilization and harvesting between the MG and SLE groups. The number of CD34+ cells in peripheral blood (PB) on the day of harvesting was 108.37 ± 59.64 x 106 cells/L. There was a significant difference in white blood cell (WBC), neutrophil, monocyte, and platelet cell counts between before and after mobilization. On the day of stem cell harvesting, variables such as WBC, neutrophil, lymphocyte, monocyte, platelet, CD34+ cell counts, and hemoglobin were not different between the MG and SLE groups. The CD34+ recovery percentage following the CD34+ selection procedure was 68.8%, whereas almost 99.9% of the T and B lymphocytes, and NK cells in the PBSC products were eliminated. CONCLUSIONS: Very first attempts in mobilizing, harvesting, and selecting CD34+ stem cells were successful, paving the way for autoimmune patients to have autologous hematopoietic stem cell transplantation in Vietnam.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucócitos , Feminino , Masculino , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Monócitos , Neutrófilos , Antígenos CD34 , Moléculas de Adesão Celular
3.
Molecules ; 28(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37110703

RESUMO

Vietnam has diverse and long-established tea plantations but scientific data on the characteristics of Vietnamese teas are still limited. Chemical and biological properties including total polyphenol and flavonoid contents (TPCs and TFCs), antioxidant activities (DPPH, ABTS, FRAP, and CUPRAC), as well as the contents of caffeine, gallic acid, and major catechins, were evaluated for 28 Vietnamese teas from North and South Vietnam. Higher values of TPCs and TFCs were found for green (non-oxidised) and raw Pu'erh (low-oxidised) teas from wild/ancient tea trees in North Vietnam and green teas from cultivated trees in South Vietnam, as compared to oolong teas (partly oxidised) from South Vietnam and black teas (fully oxidised) from North Vietnam. The caffeine, gallic acid, and major catechin contents depended on the processing, geographical origin, and the tea variety. Several good Pearson's correlations were found (r2 > 0.9) between TPCs, TFCs, the four antioxidant capacities, and the content of major catechins such as (-)-epicatechin-3-gallate and (-)-epigallocatechin-3-gallate. Results from principal component analysis showed good discriminations with cumulative variances of the first two principal components varying from 85.3% to 93.7% among non-/low-oxidised and partly/fully oxidised teas, and with respect to the tea origin.


Assuntos
Antioxidantes , Catequina , Antioxidantes/química , Cafeína/análise , Flavonoides/química , Polifenóis/análise , Catequina/química , Ácido Gálico/química , Vietnã , Chá/química , Cromatografia Líquida de Alta Pressão/métodos
4.
J Psycholinguist Res ; 52(6): 2599-2620, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37698816

RESUMO

With both the quantitative and qualitative data from 628 responses to a set of questionnaire collected from the undergraduates of three educational institutions in central Vietnam, this study analyzed learners' needs of intercultural communication competence (ICC) related to their studying of English for tourism purposes and future occupations. The methodology used for data analysis including semi-structured interviews, and the questionnaire. The findings showed that the students preferred intercultural language learning activities referring to authentic materials and real-life experience. The results also revealed the participants' great needs of various ICC attitudes and regular tasks in tourism workplaces. Particularly, they had positive attitudes in intercultural communication, and higher needs of tasks for improving discourse and behavioural competences more than other ICC dimensions. The study has implications for tourism learners, educators and related stakeholders to raise their awareness in learning, teaching and developing this long-lasting competence.


Assuntos
Estudantes , Turismo , Humanos , Idioma , Comunicação , Aprendizagem
5.
Sensors (Basel) ; 20(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093275

RESUMO

Relay communication, in which the relay forwards the signal received by a source to a destination, has a massive consideration in research, due to its ability to expand the coverage, increase the capacity, and reduce the power consumption. In this paper, we proposed and investigated energy harvesting (EH) based two-way half-duplex (TWHD) relaying sensors network using selection combining (SC) over block Rayleigh fading channel. In this model, we proposed the direct link between two sources for improving the system performance. For the system performance analysis, we investigated and derived the closed-form of the exact and upper bound Ergodic capacity (EC) and the exact form of the symbol error ratio (SER). By using the Monte Carlo simulation, the correctness of the research results is verified in the influence of the main system parameters. From the discussions, we can see that the analytical and simulation agree well with each other.

6.
Sensors (Basel) ; 20(20)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096666

RESUMO

This article describes an optical method based on the association of surface plasmon resonance (SPR) with chitosan (CS) film and its nanocomposites, including zinc oxide (ZnO) or graphene oxide (GO) for glyphosate detection. CS and CS/ZnO or CS/GO thin films were deposited on an Au chip using the spin coating technique. The characterization, morphology, and composition of these films were performed by Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angle technique. Sensor preparation conditions including the cross-linking and mobile phase (pH and salinity) were investigated and thoroughly optimized. Results showed that the CS/ZnO thin-film composite provides the highest sensitivity for glyphosate sensing with a low detection limit of 8 nM and with high reproducibility. From the Langmuir-type adsorption model and the effect of ionic strength, the adsorption mechanisms of glyphosate could be controlled by electrostatic and steric interaction with possible formation of 1:1 outer-sphere surface complexes. The selectivity of the optical method was investigated with respect to the sorption of glyphosate metabolite (aminomethylphosphonic acid) (AMPA), glufosinate, and one of the glufonisate metabolites (3-methyl-phosphinico-propionic acid) (MPPA). Results showed that the SPR sensor offers a very good selectivity for glyphosate, but the competition of other molecules could still occur in aqueous systems.

7.
BMC Med Genet ; 20(1): 115, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248375

RESUMO

BACKGROUND: Calreticulin (CALR) gene mutations are currently recommended as biomarkers in diagnosis of patients with myeloproliferative neoplasms (MPN) with Jak2 V617F negative phenotype. Our aim was to establish a rapid, low cost and sensitive assay for identification of CALR gene mutations and to validate the diagnostic performance of the established assay in a patient cohort with different clinical MPN phenotypes. METHODS: One hundred five Philadelphia-negative MPN patients, including polycythemia vera (PV), essential thrombocythaemia (ET), and primary myelofibrosis (PMF) were initially screened for JAK2 mutations by amplification-refractory mutation system (ARMS-PCR) methodology and were further subjected to detection of CALR gene mutations by our in-house assay, a PCR based amplicon length differentiation assay (PCR-ALDA). The PCR-ALDA methodology was compared with real time PCR and Sanger sequencing methods. Furthermore, the analytical sensitivity of the assay was established. RESULTS: PCR - ALDA approach was able to detect and discriminate the pseudo-positive samples containing more than 1% CALR mutant alleles. CALR mutations were not detected in 63 Jak2 V617F positive cases in all three methods. In contrast, amongst 42 Jak2 V617F negative cases, both PCR-ALDA and Sanger sequencing coherently identified 12 CALR mutants compared to 10 CALR mutants detected by real-time PCR method. CONCLUSION: PCR-ALDA can be utilized as an easy-to-use, rapid, low cost and sensitive tool in the detection of CALR mutations in Philadelphia-negative MPN patients.


Assuntos
Calreticulina/genética , Mutação , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Reação em Cadeia da Polimerase em Tempo Real , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores Tumorais , Análise Custo-Benefício , Feminino , Técnicas de Genotipagem/métodos , Humanos , Janus Quinase 2/genética , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa , Masculino , Pessoa de Meia-Idade , Fenótipo , Policitemia Vera , Mielofibrose Primária , Reação em Cadeia da Polimerase em Tempo Real/economia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Trombocitemia Essencial , Adulto Jovem
8.
Bioorg Med Chem ; 26(8): 1470-1480, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29449125

RESUMO

The increased tolerance of biofilms against disinfectants and antibiotics has stimulated research into new methods of biofilm prevention and eradication. In our previous work, we have identified the 5-aryl-2-aminoimidazole core as a scaffold that demonstrates preventive activity against biofilm formation of a broad range of bacterial and fungal species. Inspired by the dimeric nature of natural 2-aminoimidazoles of the oroidin family, we investigated the potential of dimers of our decorated 5-aryl-2-aminoimidazoles as biofilm inhibitors. A synthetic approach towards 2-aminoimidazole dimers linked by an alkyl chain was developed and a total of 48 dimers were synthesized. The linkers were introduced at two different positions, the N1-position or the N2-position, and the linker length and the substitution of the 5-phenyl ring (H, F, Cl, Br) were varied. Although, no clear correlation between linker length and biofilm inhibition was observed, a strong increase in anti-biofilm activity for almost all N1,N1'-linked dimers was obtained, compared to the respective monomers against Salmonella Typhimurium, Escherichia coli and Staphylococcus aureus. The N2,N2'-linked dimers, having a H- or F-substitution, were also found to show a strong increase in anti-biofilm activity compared to the respective monomers against these three bacterial species and against Pseudomonas aeruginosa. In addition, the obtained growth measurements suggest a broad concentration range with specific biofilm inhibition and no effect on the planktonic growth against Salmonella Typhimurium and Pseudomonas aeruginosa.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Imidazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Dimerização , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Imidazóis/síntese química , Imidazóis/química , Testes de Sensibilidade Microbiana , Micro-Ondas , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
9.
Int J Mol Sci ; 19(3)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29494554

RESUMO

The Helicobacter pylori-induced burden of gastric cancer varies based on geographical regions and ethnic grouping. Vietnam is a multiethnic country with the highest incidence of gastric cancer in Southeast Asia, but previous studies focused only on the Kinh ethnic group. A population-based cross-sectional study was conducted using 494 volunteers (18-78 years old), from 13 ethnic groups in Daklak and Lao Cai provinces, Vietnam. H. pylori status was determined by multiple tests (rapid urease test, culture, histology, and serology). cagA and vacA genotypes were determined by PCR-based sequencing. The overall H. pylori infection rate was 38.1%. Multivariate analysis showed that variations in geographical region, age, and ethnicity were independent factors associated with the risk of H. pylori acquisition. Therefore, multicenter, multiethnic, population based study is essential to assess the H. pylori prevalence and its burden in the general population. Only the E De ethnicity carried strains with Western-type CagA (82%) and exhibited significantly lower gastric mucosal inflammation compared to other ethnic groups. However, the histological scores of Western-type CagA and East-Asian-type CagA within the E De group showed no significant differences. Thus, in addition to bacterial virulence factors, host factors are likely to be important determinants for gastric mucosal inflammation and contribute to the Asian enigma.


Assuntos
Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Vigilância da População , Adolescente , Adulto , Idoso , Etnicidade , Feminino , Gastroenteropatias/epidemiologia , Gastroenteropatias/microbiologia , Gastroenteropatias/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori/classificação , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Prevalência , Vietnã/epidemiologia , Vietnã/etnologia , Virulência/genética , Fatores de Virulência/genética , Adulto Jovem
10.
Antimicrob Agents Chemother ; 59(4): 2343-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25645832

RESUMO

Metronidazole resistance is a key factor associated with Helicobacter pylori treatment failure. Although this resistance is mainly associated with mutations in the rdxA and frxA genes, the question of whether metronidazole resistance is caused by the inactivation of frxA alone is still debated. Furthermore, it is unclear whether there are other mutations involved in addition to the two genes that are associated with resistance. A metronidazole-resistant strain was cultured from the metronidazole-susceptible H. pylori strain 26695-1 by exposure to low concentrations of metronidazole. The genome sequences of both susceptible and resistant H. pylori strains were determined by Illumina next-generation sequencing, from which putative candidate resistance mutations were identified. Natural transformation was used to introduce PCR products containing candidate mutations into the susceptible parent strain 26695-1, and the metronidazole MIC was determined for each strain. Mutations in frxA (hp0642), rdxA (hp0954), and rpsU (hp0562) were confirmed by the Sanger method. The mutated sequence in rdxA was successfully transformed into strain 26695-1, and the transformants showed resistance to metronidazole. The transformants containing a single mutation in rdxA showed a low MIC (16 mg/liter), while those containing mutations in both rdxA and frxA showed a higher MIC (48 mg/liter). No transformants containing a single mutation in frxA or rpsU were obtained. Next-generation sequencing was used to identify mutations related to drug resistance. We confirmed that the mutations in rdxA are mainly associated with metronidazole resistance, and mutations in frxA are able to enhance H. pylori resistance only in the presence of rdxA mutations. Moreover, mutations in rpsU may play a role in metronidazole resistance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Metronidazol/farmacologia , DNA Bacteriano/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Genes Bacterianos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Mutação/genética , Análise de Sequência de DNA , Transformação Bacteriana
11.
Anal Chem ; 87(12): 6004-9, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-25978142

RESUMO

Glyphosate is the most widely used herbicide on a world scale for the last 40 years, for both urban and agricultural uses. Here we describe the first passive sampling method for estimating the concentration of glyphosate and AMPA (aminomethyl phosphonic acid, one of its major degradation products) in surface water. The sampling method is based on a newly developed configuration of the diffusive gradient in thin-film (DGT) technique, which includes a TiO2 binding phase, already in use for a wide range of anions. Glyphosate and AMPA were retained well on a TiO2 binding phase, and elution in a 1 mL of 1 M NaOH led to recoveries greater than 65%. We found no influence of pH or flow velocity on the diffusion coefficients through 0.8 mm polyacrylamide gels, although they did increase with temperature. TiO2 binding gels were able to accumulate up to 1167 ng of P for both glyphosate and AMPA, and linear accumulation was expected over several weeks, depending on environmental conditions. DGT sampling rates were close to 10 mL day(-1) in ultrapure water, while they were less than 1 mL day(-1) in the presence of naturally occurring ions (e.g., copper, iron, calcium, magnesium). These last results highlighted (i) the ability of DGT to measure only the freely dissolved fraction of glyphosate and AMPA in water and (ii) the needs to determine which fraction (total, particulate, dissolved, freely dissolved) is indeed bioactive.

12.
Helicobacter ; 20 Suppl 1: 8-16, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26372819

RESUMO

Three decades have passed since Warren and Marshall described the successful isolation and culture of Helicobacter pylori, the Gram-negative bacterium that colonizes the stomach of half the human population worldwide. Although it is documented that H. pylori infection is implicated in a range of disorders of the upper gastrointestinal tract, as well as associated organs, many aspects relating to host colonization, successful persistence, and the pathophysiological mechanisms of this bacteria still remain controversial and are constantly being explored. Unceasing efforts to decipher the pathophysiology of H. pylori infection have illuminated the crucially important contribution of multifarious bacterial factors for H. pylori pathogenesis, in particular the cag pathogenicity island (PAI), the effector protein CagA, and the vacuolating cytotoxin VacA. In addition, recent studies have provided insight into the importance of the gastrointestinal microbiota on the cumulative pathophysiology associated with H. pylori infection. This review focuses on the key findings of publications related to the pathogenesis of H. pylori infection published during the last year, with an emphasis on factors affecting colonization efficiency, cagPAI, CagA, VacA, and gastrointestinal microbiota.


Assuntos
Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno , Fatores de Virulência/metabolismo , Humanos
13.
J Antimicrob Chemother ; 69(7): 1796-803, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24648504

RESUMO

OBJECTIVES: Resistance to clarithromycin is the most important factor causing failure of Helicobacter pylori eradication. Although clarithromycin resistance is mainly associated with three point mutations in the 23S rRNA genes, it is unclear whether other mutations are associated with this resistance. METHODS: Two types of clarithromycin-resistant strains (low- and high-resistance strains) were obtained from clarithromycin-susceptible H. pylori following exposure to low clarithromycin concentrations. The genome sequences were determined with a next-generation sequencer. Natural transformation was used to introduce the candidate mutations into strain 26695. Etest and an agar dilution method were used to determine the MICs. RESULTS: High-resistance strains contained the mutation A2143G in the 23S rRNA genes, whereas low-resistance strains did not. There were seven candidate mutations in six genes outside of the 23S rRNA genes. The mutated sequences in hp1048 (infB), hp1314 (rpl22) and the 23S rRNA gene were successfully transformed into strain 26695 and the transformants showed an increased MIC of and low resistance to clarithromycin. The transformants containing a single mutation in infB or rpl22 (either a 9 bp insertion or a 3 bp deletion) or the 23S rRNA gene showed low MICs (0.5, 2.0, 4.0 and 32 mg/L, respectively) while the transformants containing double mutations (mutation in the 23S rRNA genes and mutation in infB or rpl22) showed higher MICs (>256 mg/L). CONCLUSIONS: Next-generation sequencing can be a useful tool for screening mutations related to drug resistance. We discovered novel mutations related to clarithromycin resistance in H. pylori (infB and rpl22), which have synergic effects with 23S rRNA resulting in higher MICs.


Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Farmacorresistência Bacteriana , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Mutação , Análise por Conglomerados , Análise Mutacional de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes Bacterianos , Helicobacter pylori/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 23S/genética , Seleção Genética , Inoculações Seriadas , Transformação Bacteriana
14.
Org Biomol Chem ; 12(22): 3671-8, 2014 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-24763714

RESUMO

A microwave-assisted protocol was developed for the construction of 2-amino-1H-imidazole/triazole conjugates starting from the previously described 2-hydroxy-2,3-dihydro-1H-imidazo[1,2-a]pyrimidin-4-ium salts. The process involves a one-pot hydrazinolysis/Dimroth-rearrangement of these salts followed by a ligand-free copper nanoparticle-catalyzed azide-alkyne Huisgen cycloaddition. The 2-amino-1H-imidazole/triazole conjugates showed moderate to high preventive activity against biofilms of S. Typhimurium, E. coli, P. aeruginosa and S. aureus. The most active compounds had BIC50 values between 1.3 and 8 µM. A remarkable finding was that introduction of the triazole moiety into the side chain of 2-aminoimidazoles with a long (C8-C13) 2N-alkyl chain did drastically improve their activity. Conclusively, the 2-amino-1H-imidazole/triazole scaffold provides a lead structure for further design and development of novel biofilm inhibitors.


Assuntos
Biofilmes/efeitos dos fármacos , Química Orgânica/métodos , Imidazóis/síntese química , Imidazóis/farmacologia , Micro-Ondas , Triazóis/síntese química , Triazóis/farmacologia , Imidazóis/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/fisiologia , Triazóis/química
15.
Chem Pharm Bull (Tokyo) ; 62(2): 185-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24492589

RESUMO

A new megastigmane glycoside, galloyl linarionoside A (1), together with 13 known compounds (2-14) were isolated from the aerial parts of Aceriphyllum rossii ENGLER. (Saxifragaceae). The chemical structures of the isolated compounds were established mainly by using nuclear magnetic resonance spectra, mass spectrometry, and modified Mosher's method. Among the isolates, compounds 4, 5, 6 and 7 showed potent inhibitory activity against the lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells with IC50 values of 12.5, 9.5, 10.5 and 9.3 µM, respectively. The anti-inflammatory effect of compound 7 was accompanied by dose-dependent decreases in the production of inducible nitric oxide synthase and cyclooxygenase-2 proteins not in the inhibitor kappa B (IκB)-dependent nuclear factor-kappa B activation.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Óxido Nítrico/imunologia , Componentes Aéreos da Planta/química , Saxifragaceae/química , Animais , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular , Proteínas I-kappa B/imunologia , Lipopolissacarídeos/imunologia , Camundongos , NF-kappa B/imunologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
16.
J Biomed Opt ; 29(6): 065004, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38846676

RESUMO

Significance: Of patients with early-stage breast cancer, 60% to 75% undergo breast-conserving surgery. Of those, 20% or more need a second surgery because of an incomplete tumor resection only discovered days after surgery. An intraoperative imaging technology allowing cancer detection on the margins of breast specimens could reduce re-excision procedure rates and improve patient survival. Aim: We aimed to develop an experimental protocol using hyperspectral line-scanning Raman spectroscopy to image fresh breast specimens from cancer patients. Our objective was to determine whether macroscopic specimen images could be produced to distinguish invasive breast cancer from normal tissue structures. Approach: A hyperspectral inelastic scattering imaging instrument was used to interrogate eight specimens from six patients undergoing breast cancer surgery. Machine learning models trained with a different system to distinguish cancer from normal breast structures were used to produce tissue maps with a field-of-view of 1 cm 2 classifying each pixel as either cancer, adipose, or other normal tissues. The predictive model results were compared with spatially correlated histology maps of the specimens. Results: A total of eight specimens from six patients were imaged. Four of the hyperspectral images were associated with specimens containing cancer cells that were correctly identified by the new ex vivo pathology technique. The images associated with the remaining four specimens had no histologically detectable cancer cells, and this was also correctly predicted by the instrument. Conclusions: We showed the potential of hyperspectral Raman imaging as an intraoperative breast cancer margin assessment technique that could help surgeons improve cosmesis and reduce the number of repeat procedures in breast cancer surgery.


Assuntos
Neoplasias da Mama , Imageamento Hiperespectral , Mastectomia Segmentar , Análise Espectral Raman , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Feminino , Análise Espectral Raman/métodos , Mastectomia Segmentar/métodos , Imageamento Hiperespectral/métodos , Mastectomia , Mama/diagnóstico por imagem , Mama/cirurgia , Mama/patologia , Pessoa de Meia-Idade , Aprendizado de Máquina
17.
J Colloid Interface Sci ; 675: 275-292, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38970913

RESUMO

Azo compounds, particularly azo dyes, are widely used but pose significant environmental risks due to their persistence and potential to form carcinogenic by-products. Advanced oxidation processes (AOPs) are effective in degrading these stubborn compounds, with Oxone activation being a particularly promising method. In this study, a unique nanohybrid material, raspberry-like CuCo alloy embedded carbon (RCCC), is facilely fabricated using CuCo-glycerate (Gly) as a template. With the incorporation of Cu into Co, RCCC is essentially different from its analogue derived from Co-Gly in the absence of Cu, affording a popcorn-like Co embedded on carbon (PCoC). RCCC exhibits a unique morphology, featuring a hollow spherical layer covered by nanoscale beads composed of CuCo alloy distributed over carbon. Therefore, RCCC significantly outperforms PCoC and Co3O4 for activating Oxone to degrade the toxic azo contaminant, Azorubin S (AS), in terms of efficiency and kinetics. Furthermore, RCCC remains highly effective in environments with high NaCl concentrations and can be efficiently reused across multiple cycles. Besides, RCCC also leads to the considerably lower Ea of AS degradation than the reported Ea values by other catalysts. More importantly, the contribution of incorporating Cu with Co as CuCo alloy in RCCC is also elucidated using the Density-Function-Theory (DFT) calculation and synergetic effect of Cu and Co in CuCo contributes to enhance Oxone activation, and boosts generation of SO4•-and •OH. The decomposition pathway of AS by RCCC + Oxone is also comprehensively investigated by studying the Fukui indices of AS and a series of its degradation by-products using the DFT calculation. In accordance to the toxicity assessment, RCCC + Oxone also considerably reduces acute and chronic toxicities to lower potential environmental impact. These results ensure that RCCC would be an advantageous catalyst for Oxone activation to degrade AS in water.

18.
RSC Adv ; 14(14): 9538-9546, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516156

RESUMO

Performing effective fluorescence quenching based on a metal nanomaterial is essential to construct fluorescence sensors. Silver nanomaterials are well known as an excellent candidate for an absorber in fluorescence sensing systems. Herein, we investigated the fluorescence quenching of rhodamine B (RhB) in the presence of triangular silver nanodisks in which perfect overlap between the absorption of the absorber and the fluorescence of the fluorophore was observed. The fluorescence quenching mechanism of RhB was investigated under various excitation wavelengths, together with measurement of the fluorescence lifetime. The quenching efficiency of RhB was proportional to the wavelength excitation. Remarkably, the highest efficiency of fluorescence quenching of RhB was achieved (∼60%). The quenching mechanism was investigated and revealed to be mostly due to the inner filter effect (IFE) mechanism, without the contribution of energy transfer. This result shows a completely different story from most previous studies based on silver nanoparticles, where energy transfer was reported to play a significant role.

19.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 5): 550-554, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38721425

RESUMO

The complex [Pt(C9H6NO)Cl(C2H4)], (I), was synthesized and structurally characterized by ESI mass spectrometry, IR, NMR spectroscopy, DFT calculations and X-ray diffraction. The results showed that the deprotonated 8-hy-droxy-quinoline (C9H6NO) coordinates with the PtII atom via the N and O atoms while the ethyl-ene coordinates in the η2 manner and in the trans position compared to the coordinating N atom. The crystal packing is characterized by C-H⋯O, C-H⋯π, Cl⋯π and Pt⋯π inter-actions. Complex (I) showed high selective activity against Lu-1 and Hep-G2 cell lines with IC50 values of 0.8 and 0.4 µM, respectively, 54 and 33-fold more active than cisplatin. In particular, complex (I) is about 10 times less toxic to normal cells (HEK-293) than cancer cells Lu-1 and Hep-G2. Furthermore, the reaction of complex (I) with guanine at the N7 position was proposed and investigated using the DFT method. The results indicated that replacement of the ethyl-ene ligand with guanine is thermodynamically more favorable than the Cl ligand and that the reaction occurs via two consecutive steps, namely the replacement of ethyl-ene with H2O and the water with the guanine mol-ecule.

20.
Environ Sci Pollut Res Int ; 31(18): 26773-26789, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456975

RESUMO

In this study, CoCr layered double hydroxide material (CoCr-LDH) was prepared and used as an effective catalyst for peroxymonosulfate (PMS) activation to degrade organics in water. The prepared CoCr-LDH material had a crystalline structure and relatively porous structure, as determined by various surface analyses. In Rhodamine B (RhB) removal, the most outstanding PMS activation ability belongs to the material with a Co:Cr molar ratio of 2:1. The removal of RhB follows pseudo-first-order kinetics (R2 > 0.99) with an activation energy of 38.23 kJ/mol and efficiency of 98% after 7 min of treatment, and the total organic carbon of the solution reduced 47.2% after 10 min. The activation and oxidation mechanisms were proposed and the RhB degradation pathways were suggested with the key contribution of O2•- and 1O2. Notably, CoCr-LDH can activate PMS over a wide pH range of 4 - 9, and apply to a wide range of organic pollutants and aqueous environments. The material has high stability and good recovery, which can be reused for 5 cycles with a stable efficiency of above 88%, suggesting a high potential for practical recalcitrant water treatment via PMS activation by heterogeneous catalysts.


Assuntos
Peróxidos , Poluentes Químicos da Água , Purificação da Água , Poluentes Químicos da Água/química , Peróxidos/química , Purificação da Água/métodos , Rodaminas/química , Cinética , Oxirredução , Catálise
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