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1.
Appl Opt ; 60(11): 3232-3241, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33983224

RESUMO

In this paper, the results of experimental characterization of an optical system consisting of a chromatic confocal displacement sensor integrated with an optical laser head are presented. As a result of integration, the part of the optical path of the displacement sensor was combined with the optical path of the laser beam. Consequently, a working distance of 250 mm for the optical system was achieved. The main aim of the characterization was to determine the calibration curve, as well as the application parameters of the system. The methodology for spectral data processing with particular emphasis on the effectiveness of various extraction algorithms is presented. The Lorentzian fitting was considered as the optimal algorithm for the optical system. Consequently, a large measuring range of 10 mm was obtained with perfect linear tendency of the calibration curve. The optical system was characterized by high accuracy equal to ±0.11% of the measuring range, as well as 1 µm resolution. Moreover, the functionality of the system was verified on materials commonly used in laser processing and additive manufacturing. Finally, the system was validated through a comparative measurement with a laser profiler.

2.
Appl Opt ; 59(29): 9108-9117, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33104621

RESUMO

In this paper, the methodology for design of the system consisting of chromatic confocal displacement sensor integrated with an optical laser head was presented. Furthermore, the results of experimental characterization of optical components of the laser head were also included in the numerical analysis. The designed chromatic confocal displacement sensor was analyzed as an assembly of components widely available on the optical market. Nevertheless, the main goal of the numerical optimization was to determine the influence of individual components of the optical path of the system on its parameters, i.e., measuring range, FWHM of the characteristic spectral peak, and intensity that reaches the detector. The optimized solution was characterized in order to determine the calibration curve, as well as other important application parameters of the system. Moreover, taking into consideration the integration aspect the caustic of the laser beam shaped by the laser head was measured. Finally, the versatility of the system was presented and discussed.

3.
Phys Rev Lett ; 125(9): 097002, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915627

RESUMO

Charge density wave (CDW) correlations are prevalent in all copper-oxide superconductors. While CDWs in conventional metals are driven by coupling between lattice vibrations and electrons, the role of the electron-phonon coupling (EPC) in cuprate CDWs is strongly debated. Using Cu L_{3} edge resonant inelastic x-ray scattering, we study the CDW and Cu-O bond-stretching phonons in the stripe-ordered cuprate La_{1.8-x}Eu_{0.2}Sr_{x}CuO_{4+δ}. We investigate the interplay between charge order and EPC as a function of doping and temperature and find that the EPC is enhanced in a narrow momentum region around the CDW ordering vector. By detuning the incident photon energy from the absorption resonance, we extract an EPC matrix element at the CDW ordering vector of M≃0.36 eV, which decreases to M≃0.30 eV at high temperature in the absence of the CDW. Our results suggest a feedback mechanism in which the CDW enhances the EPC which, in turn, further stabilizes the CDW.

4.
J Periodontal Res ; 50(4): 423-33, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25139560

RESUMO

BACKGROUND AND OBJECTIVE: Smoking cigarettes increases the risk of oral tissue damage leading to periodontal disease. Gingival fibroblasts, the predominant cell type inhabiting gingival connective tissue, play a critical role in remodeling and maintaining gingival structure. The objective of this study was to investigate the effect of long-term exposure to cigarette smoke on human gingival fibroblast survival/apoptosis and the molecular pathways involved in these cell responses. MATERIAL AND METHODS: Human gingival fibroblasts were extracted from healthy non-smokers and cultured in the presence of cigarette smoke condensate (CSC). At the end of each time point, cell growth was evaluated by means of MTT assay. Apoptotic and necrotic gene's expression was investigated by polymerase chain reaction array and by annexin V/propidium iodide staining and cell cycle assays. Western blot was used to investigate Bax and p53 proteins. These tests were supported by caspase 3 activity analyses. RESULTS: High levels of CSC decreased cell growth and deregulated cell cycle progression by increasing the G(0)/G(1) and reducing the S and G(2)/M phases of the gingival fibroblasts. Polymerase chain reaction arrays revealed the activation of several apoptotic genes by CSC, including TNF receptors, caspases, Bax and p53. This was supported by increases in the Bax and p53 protein levels as well as by an elevated activity of caspase-3 in the CSC-exposed cells. Immunofluorescence staining demonstrated that both Bax and caspase-3 displayed a cytosolic and mitochondrial distribution in the CSC-exposed gingival fibroblasts, compared to controls. The damaging effect of CSC on gingival fibroblast growth was also supported by the decrease in interleukin 6 and 8 secretion by the gingival fibroblasts. CONCLUSION: These results suggest that CSC may contribute to deregulating fibroblast functions. This can compromise fibroblast-epithelial cell interactions, which ultimately increases the risk of gingival tissue damage and the onset of periodontitis.


Assuntos
Caspase 3/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína X Associada a bcl-2/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Contagem de Células , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citosol/efeitos dos fármacos , Gengiva/citologia , Humanos , Interleucina-6/análise , Interleucina-8/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Receptores do Fator de Necrose Tumoral/efeitos dos fármacos , Fatores de Tempo
5.
J Biomed Mater Res B Appl Biomater ; 83(2): 554-61, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17465023

RESUMO

The goal of this study was to optimize key processes in recreating functional and viable palatal mucosa-like tissue that would be easy to handle and would promote wound healing. Normal human gingival fibroblasts and epithelial cells and a clinically useful biomaterial, CollaTape, were used. Structural and ultrastructural analyses showed that the gingival fibroblasts and epithelial cells adhered to the biomaterial and proliferated. Following a 6-day culture, using 10(5) fibroblasts and 10(6) epithelial cells, a well-organized palatal mucosa-like tissue was engineered. The engineered epithelium displayed various layers, including a stratum corneum, and contained cytokeratin 16-positive cells located in the supra-basal layer. This palatal mucosa-like engineered tissue was designed to meet a variety of surgical needs. The biodegradable collagen membrane (CollaTape) contributed to the flexibility of the engineered tissue. This engineered innovative tissue may contribute to the reconstruction of oral soft-tissue defects secondary to trauma, congenital defects, and acquired diseases.


Assuntos
Materiais Biocompatíveis , Gengiva/citologia , Mucosa Bucal/crescimento & desenvolvimento , Palato/citologia , Engenharia Tecidual/métodos , Colágeno/química , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Membranas Artificiais , Mucosa Bucal/química , Mucosa Bucal/citologia
6.
Rapid Commun Mass Spectrom ; 14(18): 1674-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10962489

RESUMO

The molecular ions of the title compounds are usually very unstable. The main fragmentation corresponds to the formation of p-MeC(6)H(4)CO(+) as would be expected. Another abundant fragment ion was [M - SO(2)](+) which is formed both from the original sulfone and from the rearranged sulfinate esters. There are, however, three primary ions which can be traced back to each isomeric molecular ion: p-RC(6)H(4)SO(2)(+) to the original sulfone, p-RC(6)H(4)SO(+) to the.CH(2)S(=O)O-. type sulfinate ester and p-RC(6)H(4)OH(+.) to the.CH(2)OS(=O). type sulfinate ester of which the latter seems by far to dominate. Copyright 2000 John Wiley & Sons, Ltd.

7.
Pol Arch Med Wewn ; 97(4): 359-63, 1997 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-9411413

RESUMO

Patients with severe form of common variable immunodeficiency require chronic immunoglobulin substitution. However, intravenous Ig administration may not be possible in some of them because of serious anaphylactoid reactions. It has been suggested that such patients may tolerate well Ig administration by subcutaneous infusion. A case is described (originally with IgG level of 53 mg/dl) who reacted with anaphylactic shock to intravenous immunoglobulin and now for more than 7 months at 1-2 week intervals receives immunoglobulin by subcutaneous infusion without any adverse reactions and maintaining IgG level above 400 mg/dl. In contrast to the period proceeding immunoglobulin substitution, the patient remains free of bacterial infection during last 7 months.


Assuntos
Imunodeficiência de Variável Comum/terapia , Imunoglobulina G/administração & dosagem , Feminino , Humanos , Imunização Passiva , Imunoglobulina G/análise , Injeções Subcutâneas , Pessoa de Meia-Idade , Resultado do Tratamento
9.
10.
Ultrastruct Pathol ; 6(2-3): 221-8, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6087527

RESUMO

Electron-dense round granules (ING) were found in the nuclei of fibroblastic cells of all the tumors examined by us (6 cases) and diagnosed clinically and histologically as nasopharyngeal angiofibroma (NPAF). The ING were consistently associated with this tumor and can be regarded as pathognomonic of NPAF. We studied at the ultrastructural level the composition of these particles using various cytochemical techniques. Enzymatic digestions carried out on thin sections as well as staining methods preferential or specific for nucleoproteins have revealed that ING represent tightly bound RNA-protein complexes and do not contain DNA. There are no data available that the ING takes part in the metabolism of NPAF fibroblastic cells.


Assuntos
Núcleo Celular/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Histiocitoma Fibroso Benigno/ultraestrutura , Neoplasias Nasofaríngeas/ultraestrutura , Adolescente , Criança , Fibroblastos/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Nasofaringe/ultraestrutura , RNA Neoplásico/metabolismo
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