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1.
RSC Adv ; 13(41): 28482-28492, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37771926

RESUMO

Nowadays, the use of self-cleaning surfaces is increasing globally, especially after the COVID-2019 pandemic, and the use of nanoparticles has been shown as a plausible option for this purpose. In the present study, Cu-doped SnO2 nanocrystals were successfully synthesized (in the copper content range of 0-30 mol%) using the polymeric precursor method. The structural, morphological, vibrational, and antibacterial activity were carefully studied to unveil the effect of copper ions on the properties of the hosting matrix, aiming at maximizing the usage of Cu-doped SnO2 nanocrystals. The results show fabrication of nanoparticles near their respective exciton Bohr diameter (5.4 nm for SnO2), however, monophasic SnO2 was observed up to 15 mol%. Above this limit, a secondary CuO phase was observed, as shown by the assessed X-ray diffraction (XRD), Fourier transform infrared, and Raman spectroscopy data. Furthermore, the redshift of the primary A1g vibrational mode of SnO2 is successfully described using the phonon-confinement model, demonstrating a good relationship between the Raman correlation length (L) and the crystallite size (〈D〉), the latter determined from XRD. Regarding the antibacterial activity, assessed via the disc-diffusion testing method (DDTM) while challenging two bacterial species (S. aureus and E. coli), our results suggest a rapid diffusion of the nanoparticles out of the paper disc, with a synergistic effect credited to the Sn1-xCuxO2-CuO phases contributing to the inhibition of the bacteria growth. Moreover, the DDTM data scales with cell viability, the latter analyzed using the Hill equation, from which both lethal dose 50 (LD50) and benchmark dose (BMD) were extracted.

2.
Lasers Med Sci ; 37(9): 3649-3659, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36239879

RESUMO

In this paper, breast cancer patients were monitored throughout their chemotherapy treatments (CHT), with blood serum sample Raman spectroscopy and multivariate analysis, approximately for a year. First of all, we discriminate between healthy and clinically diagnosed breast cancer patients. Breast cancer detection in terms of sensitivity and specificity were 87.14% and 90.55% respectively. Although no shifts of peaks in mean spectrum of samples from breast cancer patients were found with respect to the mean spectrum from control patients, some peaks did show clear differences in intensity, the greatest disparities found at 509, 545, 1063, 1103, 1338, 1556, 1083 and 1449 cm- 1 are associated with amino acids and phospholipid, 1246 and 1654 cm- 1, corresponding to amide III and I, respectively. Other peaks of interest encountered at 450, 661, 890, 917 and 1405 cm- 1 are associated to glutathione. Then, 6 breast cancer patients were monitored during their chemotherapy treatments, the results were in complete correspondence with their medical records, enabling a detailed study of the evolution of each patient's cancer. A special interest arose in the possible correlation between the intensity of Raman peak, 450 cm- 1, corresponding to glutathione and evolution of cancer throughout CHT, i.e., glutathione appears to be a good candidate as breast cancer biomarker. The results confirmed that Raman spectroscopy and PCA are, not only a good support to current breast cancer detection techniques, but could also be excellent techniques to monitor more efficiently breast cancer patients undergoing CHT, using blood serum samples which are a lot less invasive than other methods.


Assuntos
Neoplasias da Mama , Análise Espectral Raman , Humanos , Feminino , Análise Espectral Raman/métodos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/diagnóstico , Biomarcadores Tumorais , Análise de Componente Principal , Glutationa
3.
PLoS One ; 14(3): e0213621, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30861043

RESUMO

Based in high sensitivity and specificity reported recently in detection of the cancer, the technique of Raman spectroscopy is proposed to discriminate between breast cancer, leukemia and cervical cancer using blood serum samples from patients officially diagnosed. In order to classify Raman spectra, clustering method known as Super Paramagnetic Clustering based on statistical physics concepts with a stochastic approach was implemented. Comparing firstly average Raman spectra of the three cancers, some peaks that allowed differentiating one cancer from other were identified, however, other peaks allowed concluding that there are biochemical similarities among them. According to these spectra, the band associated with amide I (1654 cm-1) and one of two shoulders assigned to amide III (1230-1282 cm-1) allowed discriminating leukemia from breast and cervical cancer, whereas band 714 cm-1 (polysaccharides) achieves to differentiate cervical cancer from leukemia and breast cancer, and bulged region, 1040 - 1100 cm-1 (phenylalanine, phospholipid) discriminated breast cancer from leukemia and cervical cancer. Subsequently, Super Paramagnetic Clustering method was applied to Raman spectra to study similarity relationships between cancers based on the biochemical composition of serum samples. Finally, as a cross check method, the standard method to classify Raman spectra of breast cancer, leukemia and cervical cancer, known as principal components analysis, was used showing excellent agreement with results of Super Paramagnetic Clustering method. Preliminary results demonstrated that Raman spectroscopy and Super Paramagnetic Clustering method can be used to discriminate between breast cancer, leukemia and cervical cancer samples using blood serum samples.


Assuntos
Neoplasias da Mama/diagnóstico , Leucemia/diagnóstico , Neoplasias/diagnóstico , Análise Espectral Raman , Neoplasias do Colo do Útero/diagnóstico , Adolescente , Adulto , Algoritmos , Amidas , Criança , Análise por Conglomerados , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Componente Principal , Software , Processos Estocásticos , Adulto Jovem
4.
Water Sci Technol ; 2017(2): 492-508, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29851402

RESUMO

Composite material (AC-ZnO) was prepared by growing ZnO nanoparticles during the production of biomass based-activated carbon (AC) via the incorporation of zinc acetate in the process. Comprehensive analyses confirmed the presence of ZnO nanoparticles over the AC surface and described the particular nature of the composite adsorbent. Methylene blue (MB) equilibrium data fitted the Dubinin-Radushkevich model. The MB adsorption capacity was higher for the bare activated carbons (197.9-188.7 mg/g) than the activated carbons with ZnO nanoparticles (137.6-149.7 mg/g). The adsorption of the MB on the adsorbents is physical because the mean adsorption energy (E) is between 1.76 and 2.00 kJ/mol. Experiments that combine adsorption and photocatalysis were carried out with different loads of adsorbents and with and without UV-light exposure. Photocatalytic activity was identified mostly at the first stage of the adsorption process and, in the case of experiments with less load of the composite AC-ZnO, because the light obstruction effect of the activated carbon is more for higher loads. The ZnO grown over AC improves the adsorption of cations such as Pb, Al and Fe in aqueous phase (polluted river water) and provides antibacterial capacity against Escherichia coli and Salmonella typhimurium.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/análise , Salmonella typhimurium/efeitos dos fármacos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Óxido de Zinco/análise , Adsorção , Biomassa , Carvão Vegetal/análise , Fotólise
5.
Lasers Med Sci ; 33(8): 1791-1797, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29802586

RESUMO

In this work, we propose to the Raman spectroscopy as a new technique for the detection of the type 2 diabetes using blood serum samples. The serum samples were obtained from 15 patients who were clinically diagnosed with type 2 diabetes mellitus and 20 healthy volunteers. The average spectra showed equally intense peaks as, 695 cm-1, the doublet of tyrosine at 828 and 853 cm-1, phenylalanine at 1002 and 1028 cm-1, the phospholipid shoulder at 1300-1345 cm-1, and proteins (amide I) at 1654 cm-1. The major differences were found at 661 and 1404 cm-1 (glutathione), 714 (polysaccharides), 605 (Phe), 545 cm-1 (tryptophan), and the shoulder of amide III at 1230-1282 cm-1, where seem to disappear in the diabetes spectrum. On the contrary, the region that is more highlighted due to that diabetes peaks are clearly more intense was 897-955 cm-1. Principal component analysis and linear discriminate analysis were employed for developing discrimination method. The first three principal components provided a classification of the samples from healthy and diabetes patients with high sensitivity and specificity. In addition, when the first principal component was plotted as a function of the Raman shift, it revealed these shifts accounted for the greatest differences between control and diabetes samples, which coincided with the shifts of spectral differences shown by mean spectra. Our results demonstrated that serum sample Raman spectroscopy promises to become a non-invasive support tool of the currently applied techniques for type 2 diabetes detection, decreasing the false-positive cases.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Análise Espectral Raman/métodos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal
6.
J Phys Chem B ; 109(39): 18483-90, 2005 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-16853380

RESUMO

Nanocrystalline TiO2 films, surface modified with Al3+, were manufactured by depositing a TiO2 suspension containing small amounts of aluminum nitrate or aluminum chloride onto conducting glass substrates, followed by drying, compression, and finally heating to 530 degrees C. Electrodes prepared with TiO2 nanoparticles coated with less than 0.3 wt % aluminum oxide with respect to TiO2 improved the efficiency of the dye sensitized solar cell. This amount corresponds to less than a monolayer of aluminum oxide. Thus, the Al ions terminate the TiO2 surface rather than form a distinct aluminum oxide layer. The aluminum ion surface treatment affects the solar cell in different ways: the potential of the conduction band is shifted, the electron lifetime is increased, and the electron transport is slower when aluminum ions are present between interconnected TiO2 particles.

7.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 30(5): 152-156, mayo 2003. graf, tab
Artigo em Es | IBECS | ID: ibc-30239

RESUMO

Se realiza un estudio retrospectivo sobre las pacientes con cáncer epitelial de ovario diagnosticadas en el área de salud de Cabueñes (Gijón) entre 1991 y 2001. Revisamos las características de las pacientes, del tumor y del tratamiento realizado, con el fin de establecer el papel de la cirugía primaria citorreductora en el tratamiento del CEO y su posible impacto en la supervivencia de las pacientes. Durante el período del estudio se diagnosticaron 123 casos de cáncer epitelial de ovario. Todas las pacientes fueron sometidas a cirugía primaria con intención citorreductora seguida de un esquema de quimioterapia basado en platino. El tumor residual después de la cirugía se relacionó significativamente con el resultado del second look, la supervivencia global y el índice de recurrencias (AU)


Assuntos
Feminino , Humanos , Carcinoma/cirurgia , Carcinoma/diagnóstico , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/diagnóstico , Estudos Retrospectivos , Espanha , Taxa de Sobrevida , Recidiva Local de Neoplasia , Neoplasia Residual/tratamento farmacológico
8.
Chest ; 120(4): 1402-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11591588

RESUMO

Endobronchial foreign bodies are often difficult to diagnose as the cause of obstructive pneumonias and atelectasis, but once discovered, they can generally be removed, leading to immediate and dramatic resolution of symptoms. The use of flexible fiberoptic and rigid bronchoscopy to extract foreign bodies is well-known. Thoracotomy is generally reserved as a last resort due to the inherent risks of the procedure. We describe a new technique for foreign body removal utilizing steerable hydrophilic guidewires, standard sheaths, and a snare device commonly utilized in intravascular foreign body retrieval.


Assuntos
Brônquios , Cateterismo Periférico/instrumentação , Corpos Estranhos/terapia , Traqueostomia/instrumentação , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Corpos Estranhos/diagnóstico por imagem , Humanos , Masculino , Radiografia
11.
Arch Invest Med (Mex) ; 22(2): 121-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1819986

RESUMO

Serum glucose, serum immunoreactive insulin and sedimentation rate (ESR) were measured in eighteen male patients with ankylosing spondylitis (AS) and seven male healthy controls. The findings were correlated with the presence or absence of inflammatory activity of the disease. Fourteen patients had active AS with ESR of 47.0 +/- 27.7 mm; they had increased insulin levels measured as area under curve (AUC) of a glucose tolerance test 107.4 +/- 44.1 cm2 vs controls 40.8 +/- 12.6 cm2 (p less than 0.03). In 4 patients with clinically inactive AS and with ESR of 17.0 +/- 4.0 mm the insulin levels as the AUC were 83.2 +/- 38.0 cm2 vs controls (p = ns). In the whole group there was a direct correlation between ESR and serum immunoreactive insulin levels (r = 0.47 p less than 0.05). Our study suggests that AS may be associated with hyperinsulinism, whose role in the physiopathogenesis of the disease remains unknown.


Assuntos
Hiperinsulinismo/etiologia , Insulina/sangue , Espondilite Anquilosante/sangue , Adulto , Glicemia/análise , Sedimentação Sanguínea , Teste de Tolerância a Glucose , Humanos , Inflamação , Insulina/fisiologia , Ativação Linfocitária , Masculino , Espondilite Anquilosante/complicações , Espondilite Anquilosante/imunologia , Espondilite Anquilosante/patologia
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