Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Radiol Phys Technol ; 17(1): 153-164, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37991701

RESUMO

The utilization of contrast agents in magnetic resonance imaging (MRI) has become increasingly important in clinical diagnosis. However, the low diagnostic specificity of this technique is a limiting factor for the early detection of tumors. To develop a new contrast agent with a specific target for early stage tumors, we present the synthesis and characterization of a nanocontrast composed of gold nanoparticles (AuNPs), gadopentetic acid (Gd-DTPA), and epidermal growth factor (EGF). Carbodiimide-based chemistry was utilized to modify Gd-DTPA for functionalization with AuNPs. This resulted in the formation of the Au@Gd-EGF nanocontrast. The relaxation rate (1/T1) of the nanocontrast was analyzed using MRI, and cytotoxicity was determined based on cell viability and mitochondrial activity in a human breast adenocarcinoma cell line. Fourier-transform infrared spectroscopy analysis confirmed the effectiveness of carbodiimide in the formation of the Gd-DTPA-cysteamine complex in the presence of bands at 930, 1042, 1232, 1588, and 1716 cm-1. The complexes exhibited good interactions with the AuNPs. However, the signal intensity of the Au@Gd-EGF nanocontrast was lower than that of the commercial contrast agent because the r1/r2 relaxivities of the Gd-DTPA-based contrast agents were lower than those of the gadoversetamide-based molecules. The Au@Gd-EGF nanocontrast agent exhibited good biocompatibility, low cytotoxicity, and high signal intensity in MRI with active targeted delivery, suggesting significant potential for future applications in the early diagnosis of tumors.


Assuntos
Nanopartículas Metálicas , Neoplasias , Humanos , Meios de Contraste , Gadolínio DTPA/química , Ouro/química , Fator de Crescimento Epidérmico , Gadolínio/química , Nanopartículas Metálicas/química , Imageamento por Ressonância Magnética/métodos , Carbodi-Imidas
2.
Photodiagnosis Photodyn Ther ; 44: 103830, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852406

RESUMO

BACKGROUND: Hydroxyapatite (HAp) presents similarities with the human bone structure and presents properties such as biodegradability, biocompatibility, and osteoconductivity, which favors its use in prostheses implants and enables its use as a vehicle for the delivery of photosensitizers (PS) from systems of release (DDS) for photodynamic therapy applications Methods: In this work was to synthesized hydroxyapatite microspheres (meHAp), encapsulated with chloroaluminium phthalocyanine (ClAlPc), for DDS. meHAp was synthesized using vaterite as a template. The drug was encapsulated by mixing meHAp and a 50.0 mg.mL-1 ClAlPc solution. Photochemical, photophysical, and photobiological studies characterized the system. RESULTS: The images from the SEM analysis showed the spherical form of the particles. All spectroscopic results showed excellent photophysical parameters of the drug studied when served in the meHAp system. The incorporation efficiency was 57.8 %. The trypan blue exclusion test results showed a significant reduction (p < 0.05) in cell viability for the groups treated with PDT at all concentrations above 250 µg.mL-1. In 9 L/lacZ gliosarcoma cells, PDT mediated at concentrations from 250 to 62.5 µg.mL-1 reduced cell viability by more than 98 %. In the cell internalization study, it was possible to observe the internalization of phthalocyanines at 37 °C, with the accumulation of PS in the cytoplasm and inside the nucleus in the two tested concentrations. CONCLUSIONS: From all the results presented throughout the article, the meHAp system shows promise for use as a modified release system (DSD) in photodynamic therapy.


Assuntos
Gliossarcoma , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Durapatita , Óperon Lac , Microesferas , Sistemas de Liberação de Medicamentos
3.
Pharmacol Rep ; 75(4): 951-961, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37171518

RESUMO

BACKGROUND: Bacterial resistance is defined as a microorganism's capacity to develop mechanisms for resisting a determined antimicrobial. Gram-positive bacteria, such as Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), are internationally recognized among the isolates with this resistance profile. In this context, the demand for new medicines has risen, and silver nanoparticles (AgNPs) have been highlighted, especially for their anti-bacterial effects. To develop a nano-antibiotic for treating these Gram-positive strains, we herein report synthesizing and characterizing a nano-antibiotic based on AgNPs functionalized with the complex vancomycin-cysteamine. METHODS: AgNPs were produced using the bottom-up methodology and functionalized with vancomycin modified by the carbodiimide chemistry, forming Ag@vancomycin. Susceptibility tests were performed using S. aureus and E. faecalis strains to assess the bacteriostatic and bactericidal potential of the developed nano-antibiotic. RESULTS: Fourier transform infrared spectroscopy measurements showed the efficacy of vancomycin chemical modification, and the characteristic bands of AgNPs functionalization with the antibiotic. The increase in the nano-antibiotic average hydrodynamic diameter observed by dynamic light scattering proved the presence of vancomycin at the surface of AgNPs. The data from the minimum inhibitory concentration and minimal bactericidal concentration assays tested on standard and clinical planktonic strains of S. aureus and E. faecalis presented excellent performance. CONCLUSION: The results indicate the promising development of a new nano-antibiotic in which the functionalization potentiates the bacteriostatic action of AgNPs and vancomycin with greater efficacy against Gram-positive strains.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Vancomicina/farmacologia , Vancomicina/química , Staphylococcus aureus , Enterococcus faecalis , Prata/farmacologia , Cisteamina/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana
4.
Photochem Photobiol Sci ; 22(8): 1977-1989, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37115408

RESUMO

Calcium carbonate (CaCO3) exhibits a variety of crystalline phases, including the anhydrous crystalline polymorphs calcite, aragonite, and vaterite. Developing porous calcium carbonate microparticles in the vaterite phase for the encapsulation of methylene blue (MB) as a photosensitizer (PS) for use in photodynamic therapy (PDT) was the goal of this investigation. Using an adsorption approach, the PS was integrated into the CaCO3 microparticles. The vaterite microparticles were characterized by scanning electron microscopy (SEM) and steady-state techniques. The trypan blue exclusion method was used to measure the biological activity of macrophages infected with Leishmania braziliensis in vitro. The vaterite microparticles produced are highly porous, non-aggregated, and uniform in size. After encapsulation, the MB-loaded microparticles kept their photophysical characteristics. The carriers that were captured allowed for dye localization inside the cells. The results obtained in this study indicated that the MB-loaded vaterite microparticles show promising photodynamic activity in macrophages infected with Leishmania braziliensis.


Assuntos
Leishmania braziliensis , Fotoquimioterapia , Carbonato de Cálcio/farmacologia , Carbonato de Cálcio/química , Azul de Metileno/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Macrófagos
5.
Antibiotics (Basel) ; 12(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36978403

RESUMO

Klebsiella pneumoniae (K. pneumoniae) is an opportunistic bacterium that has drawn attention due to its resistance to carbapenem antibiotics. The treatment of patients with severe infections has been challenging. Thus, silver nanoparticles (AgNPs) have been applied for their antimicrobial effects. This work aims to analyze the synergistic effect of the carbapenem antibiotic Imipenem with AgNPs against different susceptibility clinical profiles of K. pneumoniae. The silver nanoparticles were synthesized by bottom-up methodology and capped with alpha-lipoic acid. Susceptibility tests were performed using four K. pneumoniae strains with different susceptibility profiles to Imipenem. The strains were induced to form a biofilm for 48 h. Crystal violet and Resazurin assays were performed to determine biofilm formation and minimal inhibitory concentration, respectively. The reduction in Imipenem concentration with the association of nanoparticles was found in all strains studied in planktonic form, and the synergism between silver nanoparticles and Imipenem was demonstrated through the analysis of the fractional inhibitory concentration index. The viability percentage was reduced at rates ≥80% in the biofilm analysis, characterized by the minimal biofilm inhibitory concentration. The study's proposed association resulted in inhibitory effects on different K. pneumoniae profiles, both in planktonic forms and biofilm, with peculiar behavior in the Imipenem-resistant profile.

6.
Am J Infect Control ; 51(8): 871-878, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36581226

RESUMO

BACKGROUND: Multidrug-resistant bacteria are one of the world's biggest health problems; therefore, improving the spectrum of action of antibiotics could be necessary to reverse this situation. Amikacin and silver salts have well-known antimicrobial properties. However, both drugs lost their effectiveness against some bacteria, such as Acinetobacter baumannii. This work aims to develop a nanodrug from silver nanoparticles (AgNPs) functionalized with Amikacin against multidrug-resistant Acinetobacter baumannii. METHODS: AgNPs were produced using the bottom-up methodology and functionalized with Amikacin modified by the carbodiimide-based chemistry, forming AgNPs@Amikacin. Susceptibility tests were performed using Amikacin-resistant Acinetobacter baumannii strains to assess the bacteriostatic and bactericidal potential of the developed nanodrug. The clinical strains were induced to form a biofilm, and biomass quantification and the metabolic activity were determined. RESULTS: The AgNPs have a hydrodynamic diameter of the particles with a bimodal distribution, with a size of 37.84 nm. The FT-IR spectrum of AgNPs@Amikacin exhibits vibrational modes corresponding to Amikacin, confirming the conjugation to AgNPs. Susceptibility testing demonstrated a minimal inhibitory and bactericidal concentration of < 0.5 µg/mL. The AgNPs@Amikacin reduced the biofilm metabolic activity of Acinetobacter baumannii at rates ≥ 50%, characterized by the minimal biofilm inhibition concentrations. CONCLUSIONS: Results demonstrate a promising development of a new nanodrug with lower concentrations, less toxicity, and greater efficacy against multidrug-resistant Acinetobacter baumannii.


Assuntos
Acinetobacter baumannii , Nanopartículas Metálicas , Humanos , Amicacina/farmacologia , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
7.
Photodiagnosis Photodyn Ther ; 39: 102997, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35781094

RESUMO

BACKGROUND: Epidermal Growth Factor Receptor (EGFR receptor) is encoded by the EGFR gene. EGFR receptor signaling pathways are activated by EGF protein, regulating cell actions. Overexpression of EGFR receptor may be linked to malignancies with a poor prognosis. As a result, EGFR receptor is being studied for a variety of tumor diagnostics, spurring the development of innovative approaches to increase quality and efficiency. Nanomaterials can recognize cancer cells by specifically targeting of molecular pathways, underscoring the importance of nanomedicine. In this study, we synthesized EGFR-specific nanomarkers by functionalizing EGF protein and Chlorin e6 in gold nanoparticles. These nanoparticles use active targeting to deliver EGF protein to EGFR receptor, and Chlorin e6 serves as a fluorescent marker molecule METHODS: Nanomarkers were examined in vitro in MDA-MB-468 and M059J cell lines. Confocal microscopy and flow cytometry were used to examine the distribution, uptake, internalization, and fluorescence intensity of nanomarkers in vitro RESULTS: The results show that both lines examined accumulate nanomarkers. However, MDA-MB-468 had the highest intensity due to its EGFR receptor overexpression properties CONCLUSION: The findings point to ideal properties for detecting EGFR receptor overexpressed cells.


Assuntos
Neoplasias da Mama , Glioblastoma , Nanopartículas Metálicas , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB , Feminino , Glioblastoma/metabolismo , Ouro , Humanos , Fotoquimioterapia/métodos
8.
Photodiagnosis Photodyn Ther ; 38: 102850, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35395414

RESUMO

BACKGROUND: The use of nanotechnology has been widely used in biomedical science, including orthopedic implants, tissue engineering, cancer therapy and drug elution from nanoparticle systems, such as poly-caprolactone (PCL) nanoparticles, which stand out mainly for their biocompatibility, being considered as effective carriers for photosensitizing drugs (PS) in photodynamic therapy (PDT) protocols. METHODS: This manuscript describes the synthesis and characterization of PCL nanoparticles for controlled release of the drug chloro-aluminum phthalocyanine (ClAlPc) as a photosensitizer for application in PDT. The PCL-ClAlPc nanoparticles were developed by the nanoprecipitation process. The structure and morphology of the nanoparticles were studied with scanning electron microscopy (SEM) and with Fourier transform infrared (FTIR). The size of nanomaterials was studied using the Dynamic Light Scattering (DLS) method. Photophysical and photochemical characterizations were performed. Subsequently, photobiological studies were also used to characterize the system. RESULTS: The nanoparticles had an average diameter of 384.7 ± 138.6 nm and a polydispersity index of 0.153. SEM analysis revealed that the system formed a spherical shape typical of these delivery systems. Charging efficiency was 82.1% ± 1.2%. The phthalocyanine-loaded PCL nanoparticles maintained their photophysical behavior after encapsulation. Cell viability was determined after the dark toxicity test, and it was possible to observe that there was no evidence of toxicity in the dark, for all concentrations tested. The assay also revealed that adenocarcinoma cells treated with free ClAlPc and in the nanoformulation showed 100% cell death when subjected to PDT protocols. The intracellular location of the photosensitizer indicated a high potential for accumulation in the cytoplasm and nucleus. CONCLUSIONS: From the photophysical, photochemical and photobiological analyzes obtained, it was possible to observe that the development of PCL nanoparticles encapsulated with ClAlPc, by the nanoprecipitation method was adequate and that the in vivo release study is efficient to reduce the release rate and attenuate the burst of PS loaded on PCL nanoparticles. The results reinforce that the use of this system as drug delivery systems is useful in PDT protocols.


Assuntos
Nanopartículas , Fotoquimioterapia , Caproatos , Portadores de Fármacos/química , Indóis , Isoindóis , Lactonas , Nanopartículas/química , Compostos Organometálicos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Poliésteres/química
9.
Photodiagnosis Photodyn Ther ; 38: 102818, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35331952

RESUMO

BACKGROUND: Hydrogel systems are increasingly gaining visibility involving biomedicine, tissue engineering, environmental treatments, and drug delivery systems. These systems have a three-dimensional network composition and high-water absorption capacity, are biocompatible, allowing them to become an option as photosensitizer carriers (PS) for applications in Photodynamic Therapy (PDT) protocols. METHODS: A nanohydrogel system (NAHI), encapsulated with chloroaluminium phthalocyanine (ClAlPc) was synthesized for drug delivery.. NAHI was synthesized using gelatin as based polymer by the chemical cross-linking technique. The drug was encapsulated by immersing the hydrogel in a 1.0 mg.mL-1 ClAlPc solution. The external morphology of NAHI was examined by scanning electron microscopy (SEM). The degree of swelling of the synthesized system was evaluated to determine the water absorption potential. The produced nanohydrogel system was characterized by photochemical, photophysical and photobiologial studies. RESULTS: The images from the SEM analysis showed the presence of three-dimensional networks in the formulation. The swelling test demonstrated that the nanohydrogel freeze-drying process increases its water holding capacity. All spectroscopic results showed excellent photophysical parameters of the drug studied when served in the NAHI system. The incorporation efficiency was 70%. The results of trypan blue exclusion test have shown significant reduction (p < 0.05) in the cell viability for all groups treated with PDT, in all concentrations tested. In HeLa cells, PDT mediated by 0,5 mg.mL-1 ClAlPc encapsulated in NAHI showed a decrease in survival close to 95%. In the internalization cell study was possible to observe the internalization of phthalocyanine after one hour of incubation, at 37 °C, with the the accumulation of PS in the cytoplasm and inside the nucleus at both concentrations tested. CONCLUSIONS: Given the peculiar performance of the selected system, the resulting nanohydrogel is a versatile platform and display potential applications as controlled delivery systems of photosensitizer for photodynamic therapy application.


Assuntos
Hidrogéis , Fotoquimioterapia , Fármacos Fotossensibilizantes , Gelatina , Células HeLa , Humanos , Indóis , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia
10.
Photodiagnosis Photodyn Ther ; 38: 102796, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35263669

RESUMO

Triple-negative breast cancer (TNBC) overexpresses the Epidermal Growth Factor Receptor (EGFR), a characteristic of different types of tumors, linked to worse disease prognosis and risk of recurrence. Conventional treatments are also aggressive and can be morbid.. Therefore, t improvement and development of new methods are notorious. Photodynamic Therapy (PDT) is an effective method for treating different types of cancer by using light radiation to activate a photosensitizing agent (drug) in molecular oxygen presence, promoting cell death., Improving drug uptake in target cells could contribute to PDT efficiency. Accordingly, we developed a bifunctional nanoprobe (BN), used in PDT as a a treatment method in vivo against breast cancer. The BN uses gold nanoparticles with active targeting through the Epidermal Growth Factor (EGF) protein and Chlorine e6 (Ce6) carriers. We evaluated the therapeutic efficacy of in vivo xenograft in 4 groups: Saline, BN, Ce6+PDT, and BN+PDT. As a result, we observed that the BN+PDT group exhibited an excellent effect with greater selectivity to tumor tissue and tissue damage when compared to the Saline, BN, and Ce6+PDT groups. The results indicate a potential impact on breast cancer treatment in vivo.. In conclusion, our data propose that the BN developed heightened PDT efficacy through cellular DNA repair effects and tumor microenvironment.


Assuntos
Clorofilídeos , Nanopartículas Metálicas , Nanopartículas , Fotoquimioterapia , Porfirinas , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Ouro/farmacologia , Ouro/uso terapêutico , Xenoenxertos , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral
11.
Pharmaceutics ; 15(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36678728

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) have some limitations in the physiological environment, however, a modification on their surface, such as a core-shell structure with gold (SPIONs@Au), can enhance their applicability. In this study, SPIONs were synthesized by the chemical coprecipitation method, stabilized by sodium citrate, and followed by the gold-coating process. SPIONs@Au were functionalized with EGF-α-lipoic acid and chlorin e6 (Ce6)-cysteamine complexes, composing a Theranostic Nanoprobe (TP). The outcomes showed that the SPIONs@Au had changed in color to red and had an absorption band centered at 530 nm. The coating was verified in the TEM micrographs in bright and dark fields by EDS mapping, which indicated the presence of Au and Fe. The Ce6-cysteamine complex had a resonant band at 670 nm that enabled the diagnosis of biological samples using fluorescence analysis. In the measure of TNBC cell uptake, the maximum value of TP fluorescence intensity was obtained within 4 h of internalization. At 2 h, the incorporation of the TP in the cytoplasm as well as in the nuclei was observed, suggesting that it could be employed as a diagnostic marker. The PTT results showed significant percentages of apoptosis in the TNBC cell line, which confirms the efficacy of the TP.

12.
Artif Intell Med ; 120: 102161, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34629149

RESUMO

Early-stage detection of cutaneous melanoma can vastly increase the chances of cure. Excision biopsy followed by histological examination is considered the gold standard for diagnosing the disease, but requires long high-cost processing time, and may be biased, as it involves qualitative assessment by a professional. In this paper, we present a new machine learning approach using raw data for skin Raman spectra as input. The approach is highly efficient for classifying benign versus malignant skin lesions (AUC 0.98, 95% CI 0.97-0.99). Furthermore, we present a high-performance model (AUC 0.97, 95% CI 0.95-0.98) using a miniaturized spectral range (896-1039 cm-1), thus demonstrating that only a single fragment of the biological fingerprint Raman region is needed for producing an accurate diagnosis. These findings could favor the future development of a cheaper and dedicated Raman spectrometer for fast and accurate cancer diagnosis.


Assuntos
Melanoma , Neoplasias Cutâneas , Biópsia , Humanos , Aprendizado de Máquina , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Análise Espectral Raman
13.
PLoS One ; 15(3): e0223461, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32182246

RESUMO

Monitoring of blood glucose is an invasive, painful and costly practice in diabetes. Consequently, the search for a more cost-effective (reagent-free), non-invasive and specific diabetes monitoring method is of great interest. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy has been used in diagnosis of several diseases, however, applications in the monitoring of diabetic treatment are just beginning to emerge. Here, we used ATR-FTIR spectroscopy to evaluate saliva of non-diabetic (ND), diabetic (D) and insulin-treated diabetic (D+I) rats to identify potential salivary biomarkers related to glucose monitoring. The spectrum of saliva of ND, D and D+I rats displayed several unique vibrational modes and from these, two vibrational modes were pre-validated as potential diagnostic biomarkers by ROC curve analysis with significant correlation with glycemia. Compared to the ND and D+I rats, classification of D rats was achieved with a sensitivity of 100%, and an average specificity of 93.33% and 100% using bands 1452 cm-1 and 836 cm-1, respectively. Moreover, 1452 cm-1 and 836 cm-1 spectral bands proved to be robust spectral biomarkers and highly correlated with glycemia (R2 of 0.801 and 0.788, P < 0.01, respectively). Both PCA-LDA and HCA classifications achieved an accuracy of 95.2%. Spectral salivary biomarkers discovered using univariate and multivariate analysis may provide a novel robust alternative for diabetes monitoring using a non-invasive and green technology.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Glucose/análise , Insulinas/uso terapêutico , Monitorização Fisiológica/métodos , Saliva/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Animais , Biomarcadores , Análise Custo-Benefício , Confiabilidade dos Dados , Diabetes Mellitus Experimental/induzido quimicamente , Análise Discriminante , Masculino , Análise de Componente Principal , Curva ROC , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Estreptozocina/farmacologia
14.
Photodiagnosis Photodyn Ther ; 29: 101592, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31706048

RESUMO

BACKGROUND: The increase in the incidence of Cervical Cancer in the female population worldwide has been an issue that deserves further attention from the scientific community. Several studies have already proven the relationship of its development with the molecular mechanisms that Human Papillomavirus (HPV) induces in cervical cells. The gene amplification provided by molecular biology techniques has been used as the gold standard diagnostic method of this virus because of its high specificity and sensitivity.However, the high investments associated with the acquisition of reagents, equipment and labor demonstrate the need for the development of more accessible techniques that present the same accuracy. FT-IR spectroscopy has been studied as an inexpensive and easily accessible technology that can provide the differentiation of malignant and benign cells. This study aimed to demonstrate the effectiveness and sensitivity of molecular analysis by PCR in relation to cytological analysis and to evaluate the sensitivity of FT-IR spectroscopy in the diagnosis of HPV for cervical cancer prevention. METHODS: Cervical fluid samples obtained from 50 patients with absence of cellular lesion by cytological analysis were analyzed by molecular and spectroscopic analyzes. Oncotic colpocitology analysis was performed by the Papanicolaou staining, amplification of the L1 viral gene by PCR was performed using primers MY09 and MY11 and biochemical analysis of the fluids by FT-IR was performed using the Spectrum 400 system equipped with a microscope. RESULTS: Of the 50 patients without evident morphological alteration of the cells, seven were diagnosed by molecular analysis as positive for presence of HPV. Principal component analysis of spectroscopy was not able to separate the negative samples from the HPV positive samples and, therefore, did not present as an effective diagnostic technique. CONCLUSIONS: We highlight the efficacy, sensitivity and specificity of molecular biology by PCR in the identification of the virus and we emphasize that more studies should be used for the application of FT-IR spectroscopy in the diagnosis of this infection and its application in the prevention of cervical cancer.


Assuntos
Alphapapillomavirus/genética , Infecções por Papillomavirus/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Genes Virais , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Infecções por Papillomavirus/diagnóstico por imagem , Infecções por Papillomavirus/patologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier , Adulto Jovem
16.
Res. Biomed. Eng. (Online) ; 34(4): 350-355, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-984962

RESUMO

Abstract Introduction Tendinopathy, a disease involving tendon inflammation and damage, results in considerable productivity and economic losses for the patient and the society. Currently available diagnosis/ treatment monitoring modalities are less efficacious and highly subjective, underlying the need for better tools. Previously, we have shown that Fourier Transform Infrared (FTIR) spectroscopy has potential in tendinopathy diagnosis/ monitoring, when combined with multivariate statistical analysis. The current study explores the spectral range that gave the best results in statistical analysis, to discover protein secondary structures associated with tendon injury and recovery that can act as markers of disease. Methods Animals (n=60) underwent a surgery in which Achilles tendon were injured by dropping a 20g weight. Rats were divided into three groups (n=20) - control (C), Achilles tendon injury (I) and Achilles tendon injury treated with amniotic membrane fragment treated (T). FTIR spectra were obtained from each group 3, 7, 14, and 28 days post injury/ treatment. Results Triple helix, β-turn, and disordered structure levels differ between control, injured and treated tendons over the time period studied. Parallel β-sheets increase steadily over time in treated tendons compared to control and injured. Conclusion Combined analysis of Triple helix, β- sheets, β-turn, and disordered structure levels may be useful for tendinopathy diagnosis and treatment monitoring. However, further studies in this area are required to confirm the findings.

17.
Lasers Med Sci ; 33(3): 647-653, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28990144

RESUMO

Candida albicans is an opportunistic fungal producing both superficial and systemic infections in immunocompromised patients. Furthermore, it has been described an increase in the frequency of infections which have become refractory to standard antifungal therapy. Photodynamic antimicrobial chemotherapy (PACT) is a potential antimicrobial therapy that combines visible light and a nontoxic dye, known as a photosensitizer, producing reactive oxygen species (ROS) that can kill the treated cells. The objective of this study was to investigate the effects of PACT, using chlorin e6, as a photosensitizer on C. albicans. In this work, we studied the effect of PACT on both cell growth and biofilm formation by C. albicans. In addition, both ROS production and cell permeability were determined after PACT. PACT inhibited both growth and biofilm formation by C. albicans. We have also observed that PACT increased both ROS production (six times) and cell membrane permeability (five times) in C. albicans. PACT decreased both cell growth and biofilm development. The effect of PACT using chlorin e6 on C. albicans could be associated with an increase in ROS production, which could increase cell permeability, producing permanent damage to the cell membranes, leading to the cell death.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Candida albicans/efeitos dos fármacos , Clorofilídeos , Testes de Sensibilidade Microbiana
18.
J Biophotonics ; 11(4): e201700256, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29160619

RESUMO

Tendinopathy, an important sports injury afflicting athletes and general public, is associated with huge economic losses. The currently used diagnostic tests are subjective, show moderate sensitivity and specificity; while treatment failures persist despite advances in therapy. This highlights the need for tendinopathy diagnostic and treatment monitoring tools. This study investigates tendon injury, natural healing and effect of treatment using ATR-FTIR complemented with histopathology. Control (C), injured (I) and treated (T) rat tendons were extracted 3, 7, 14 and 28 days post-injury/treatment, representing phases of healing; and subjected to hematoxylin & eosin staining as well as spectroscopy. While C showed no change, I- and T-related histological changes could be clearly observed in stained sections. ATR-FTIR spectra highlighted the biochemical changes within groups. Multivariate analysis could classify C, I and T with 75%; different days between groups with 84%; and different days within group with 65% efficiency. Results suggest that such analysis can not only identify C, I or T but also different phases of healing. Difference between I and T at different time points also suggest change in rate of healing. Further studies may help develop this technique for clinical diagnosis and treatment monitoring in future.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Tendinopatia/diagnóstico , Tendinopatia/terapia , Animais , Masculino , Análise Multivariada , Ratos , Ratos Wistar , Tendinopatia/patologia , Resultado do Tratamento
20.
Lasers Med Sci ; 32(6): 1245-1252, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28503718

RESUMO

Even with the advances of conventional treatment techniques, the nervous system cancer prognosis is still not favorable to the patient which makes alternative therapies needed to be studied. Photodynamic therapy (PDT) is presented as a promising therapy, which employs a photosensitive (PS) agent, light wavelength suitable for the PS agent, and molecular oxygen, producing reactive oxygen species in order to induce cell death. The aim of this study is to observe the PDT action in gliosarcoma cell using a chlorin (Photodithazine, PDZ). The experiments were done with 9L/lacZ lineage cells, grown in a DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin solution and put in a culture chamber at 37 °C with an atmosphere of 5% CO2. The PS agent used was the PDZ to an LED light source device (Biopdi/IRRAD-LED 660) in the 660-nm region. The location of the PS agent was analyzed by fluorescence microscopy, and cell viability was analyzed by MTT assay (mitochondrial activity), exclusion by trypan blue (cell viability), and morphological examination through an optical microscope (Leica MD 2500). In the analysis of the experiments with PDZ, there was 100% cell death at different concentrations and clear morphological differences in groups with and without treatment. Furthermore, it was observed that the photodithazine has been focused on all nuclear and cytoplasmic extension; however, it cannot be said for sure whether the location is in the inside core region or on the plasma membrane. In general, the PDZ showed a promising photosensitive agent in PDT for the use of gliosarcoma.


Assuntos
Gliossarcoma/patologia , Glucosamina/análogos & derivados , Fotoquimioterapia/métodos , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Forma Celular/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Glucosamina/farmacologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Azul Tripano/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...