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1.
Int J Cancer ; 142(7): 1453-1466, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29139122

RESUMEN

As a prophylactic cancer vaccine, human amniotic membrane epithelial cells (hAECs) conferred effective protection in a murine model of colon cancer. The immunized mice mounted strong cross-protective CTL and antibody responses. Tumor burden was significantly reduced in tumor-bearing mice after immunization with hAECs. Placental cancer immunotherapy could be a promising approach for primary prevention of cancer. In spite of being the star of therapeutic strategies for cancer treatment, the results of immunotherapeutic approaches are still far from expectations. In this regard, primary prevention of cancer using prophylactic cancer vaccines has gained considerable attention. The immunologic similarities between cancer development and placentation have helped researchers to unravel molecular mechanisms responsible for carcinogenesis and to take advantage of stem cells from reproductive organs to elicit robust anti-cancer immune responses. Here, we showed that vaccination of mice with human amniotic membrane epithelial cells (hAECs) conferred effective protection against colon cancer and led to expansion of systemic and splenic cytotoxic T cell population and induction of cross-protective cytotoxic responses against tumor cells. Vaccinated mice mounted tumor-specific Th1 responses and produced cross-reactive antibodies against cell surface markers of cancer cells. Tumor burden was also significantly reduced in tumor-bearing mice immunized with hAECs. Our findings pave the way for potential future application of hAECs as an effective prophylactic cancer vaccine.


Asunto(s)
Adenocarcinoma/patología , Amnios , Vacunas contra el Cáncer/farmacología , Neoplasias del Colon/patología , Células Epiteliales , Adenocarcinoma/inmunología , Animales , Neoplasias del Colon/inmunología , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Vacunación
2.
J Microsc ; 265(1): 101-110, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27546192

RESUMEN

Behavioural stress has shown to strongly affect neurotransmission within the neocortex. In this study, we analysed the effect of an acute stress model on density and distribution of neurotransmitter-containing vesicles within medial prefrontal cortex. Serial section transmission electron microscopy was employed to compare two groups of male rats: (1) rats subjected to foot-shock stress and (2) rats with sham stress as control group. Two-dimensional (2D) density measures are common in microscopic images and are estimated by following a 2D path in-section. However, this method ignores the slant of the active zone and thickness of the section. In fact, the active zone is a surface in three-dimension (3D) and the 2D measures do not accurately reflect the geometric configuration unless the active zone is perpendicular to the sectioning angle. We investigated synaptic vesicle density as a function of distance from the active zone in 3D. We reconstructed a 3D dataset by estimating the thickness of all sections and by registering all the image sections into a common coordinate system. Finally, we estimated the density as the average number of vesicles per area and volume and modelled the synaptic vesicle distribution by fitting a one-dimensional parametrized distribution that took into account the location uncertainty due to section thickness. Our results showed a clear structural difference in synaptic vesicle density and distribution between stressed and control group with improved separation by 3D measures in comparison to the 2D measures. Our results showed that acute foot-shock stress exposure significantly affected both the spatial distribution and density of the synaptic vesicles within the presynaptic terminal.


Asunto(s)
Biometría/métodos , Imagenología Tridimensional/métodos , Microscopía Electrónica de Transmisión/métodos , Corteza Prefrontal/patología , Estrés Psicológico , Vesículas Sinápticas/ultraestructura , Animales , Modelos Animales de Enfermedad , Masculino , Ratas
3.
Magn Reson Chem ; 54(2): 119-25, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26332515

RESUMEN

Hydrogen magnetic resonance spectroscopy ((1) H-MRS) is a non-invasive technique which provides a 'frequency-signal intensity' spectrum of biochemical compounds of tissues in the body. Although this method is currently used in human brain studies, accurate classification of in-vivo (1) H-MRS is a challenging task in the diagnosis of brain tumors. Problems such as overlapping metabolite peaks, incomplete information on background component and low signal-to-noise ratio disturb classification results of this spectroscopic method. This study presents an alternative approach to the soft independent modeling of class analogy (SIMCA) technique, using non-negative matrix factorization (NMF) for dimensionality reduction. In the adopted strategy, the performance of SIMCA was improved by application of a robust algorithm for classification in the presence of noisy measurements. Total of 219 spectra from two databases were taken by water-suppressed short echo-time (1) H-MRS, acquired from different subjects with different stages of glial brain tumors (Grade II (26 cases), grade III (24 cases), grade IV (41 cases), as well as 25 healthy cases). The SIMCA was performed using two approaches: (i) principal component analysis (PCA) and (ii) non-negative matrix factorization (NMF), as a modified approach. Square prediction error was considered to assess the class membership of the external validation set. Finally, several figures of merit such as the correct classification rate (CCR), sensitivity and specificity were calculated. Results of SIMCA based on NMF showed significant improvement in percentage of correctly classified samples, 91.4% versus 83.5% for PCA-based model in an independent test set.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Algoritmos , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Neoplasias Encefálicas/patología , Colina/análisis , Creatina/análisis , Glioma/patología , Glicina/análisis , Humanos , Clasificación del Tumor , Análisis de Componente Principal , Espectroscopía de Protones por Resonancia Magnética/métodos
4.
Eur J Cancer Care (Engl) ; 19(3): 352-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19912299

RESUMEN

Fourier transform infrared spectra of blood samples obtained from healthy women and those affected by breast cancer have been analysed statistically. Several spectral differences were detected in the N-H stretching signals of amides I and II bands. The position of alpha-helix and beta-sheet amide I bands would shift in cancerous blood samples during stage development. Investigating the absorbance bands in the Fourier transform infrared spectra during the different stages of cancer, many changes are clearly observed in the intensity of a single band or the absorbance ratio of signals, indicating the changes that would occur in blood ingredients during cancer stages. These observations imply that the information is useful for diagnostic study of breast cancer and malignant abnormalities by infrared spectroscopy of whole blood samples. Finally, linear discriminant analysis was applied for classification of cancer case and normal case blood samples. The accuracy of the proposed method was 97.9%.


Asunto(s)
Neoplasias de la Mama/sangre , Neoplasias de la Mama/diagnóstico , Proteínas de Neoplasias/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Amidas/química , Femenino , Humanos , Análisis Multivariante , Proteínas de Neoplasias/sangre , Análisis Espectral/métodos
5.
J Mycol Med ; 28(4): 628-636, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30126717

RESUMEN

OBJECTIVE: Candidiasis is one of the most opportunistic fungal infections in immunocompromised patients. The emergence of multidrug-resistant Candida species necessitates the development of novel antifungal agents. Seeking to the discovery of natural antifungal agents, this study aimed to synthesize a novel formulated nanocomposite containing Indolicidin (IN), antimicrobial peptide, and Graphene oxide (GO), kind of nanomaterial, against Candida growth using in vitro and in vivo experiments for the first time. METHODS: The formulated nanocomposite (GO-IN) synthetized and was characterized using scanning electron microscopy, X-ray power diffraction, and fourier transform infrared method analysis. The in vitro antifungal activity of fluconazole (FLU), GO, IN, and GO-IN was determined against Candida albicans (C. albicans) compared to control groups, cell cytotoxicity assay on human intestinal epithelial cells (IEP) and hemolytic activities were performed. Moreover, in vivo experiments of nanocomposite were assessed in BALB/c mice. RESULTS: Our results showed that nanocomposite had the highest inhibitory effect against C. albicans (MIC 3.12µg/mL) compared with flu (MIC 4µg/mL), IN (MIC 12.5µg/mL), and GO (MIC 6.25µg/mL). Viability of human intestinal cell line at the MIC concentration (3.12µg/mL) of nanocomposite (GO-IN) was detected as 60% (P<0.05). The results of hemolytic activity showed that nanocomposite cause 2.73% of red blood cell membrane damage. For in vivo experiments, infected mice were successfully treated with GO-IN once a day within 7 days. GO-IN treated group eliminated the Candida infection in the spleen and liver of BALB/c mice (P=0.001) similar to fluconazole. There was no significant difference in histological manifestations between flu and GO-IN groups. CONCLUSION: This study suggests that synergistic combination of GO and IN provide a new option, representing a potential therapeutic efficiency against disseminated candidiasis in an animal model as well as might be used as adjunct therapy in the management of candidiasis. However, further investigation is needed to evaluate the efficacy of the nanocomposite.


Asunto(s)
Antifúngicos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Grafito/química , Nanocompuestos/química , Animales , Antifúngicos/administración & dosificación , Antifúngicos/síntesis química , Péptidos Catiónicos Antimicrobianos/farmacología , Candidiasis/microbiología , Candidiasis/patología , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Nanocompuestos/ultraestructura , Resultado del Tratamiento
6.
J Pharm Biomed Anal ; 31(3): 571-7, 2003 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-12615246

RESUMEN

An analytical procedure has been developed for quantitative determination of cephalosporin C in complex fermentation broths. The method is based on the partial least-square treatment of data obtained by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrometric method in the wavenumber range of 1227-1257 cm(-1). Absorbance spectra were employed for measurement using a set of eleven binary aqueous standard solutions of cep halosporin C and deacetoxycephalosporin C. The method is simple, rapid and accurate (to within +/-1.49%). The developed method has been used to measure cephalosporin C in aqueous solution of biosynthetic samples only after freeze drying the sample at -30 degrees C and dissolving it in distilled water.


Asunto(s)
Cefalosporinas/análisis , Calibración , Cefalosporinas/biosíntesis , Cromatografía Líquida de Alta Presión , Medios de Cultivo , Fermentación , Indicadores y Reactivos , Estándares de Referencia , Programas Informáticos , Soluciones , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
7.
Cell Prolif ; 47(6): 615-23, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25252214

RESUMEN

OBJECTIVES: To characterize potency of menstrual blood-derived stem cells (MenSCs) for future cell therapies, we examined differentiation potential of MenSCs into adipocytes. MATERIALS AND METHODS: Differentiation potential of MenSCs in comparison to bone marrow stem cells (BMSCs) was assessed in conventional culture medium. Differentiation potential of MenSCs into adipocytes was improved using different combinations of growth factors and hormones. RESULTS: First, we demonstrated that MenSCs preserve their appearance and karyotypic stability during passages. Although these cells express mesenchymal stem cells markers, they cannot simply be classified as mesenchymal stem cells due to expression of embryonic stem cells marker, OCT-4. Oil red O staining showed that differentiated MenSCs in conventional medium with/without retinoic acid (protocols 1 and 2) did not attain adipocyte characteristics, whereas differentiated BMSCs in conventional medium accumulated oil vacuoles typically. Nevertheless, real-time RT-PCR results showed that LPL gene expression was up-regulated in both protocols 1 and 2, whereas LEPR was up-regulated only in protocol 2 (fortified with retinoic acid). Surprisingly, protocol 3 (including rosiglitazone) had odd influence on mRNA expression of all genes (LEPR, LPL and PPAR-γ). Oil red O staining confirmed fat-producing ability of MenSCs under protocol 3. CONCLUSIONS: Presented data suggest an efficient differentiation protocol for in vitro production of MenSC-derived adipocytes. These cells are suggested to be an apt alternative to BMSCs for future stem cell therapy of soft tissue injuries.


Asunto(s)
Células Madre/citología , Adipogénesis/efectos de los fármacos , Adulto , Células de la Médula Ósea/citología , Linaje de la Célula , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Lipoproteína Lipasa/genética , Lipoproteína Lipasa/metabolismo , Menstruación , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , ARN Mensajero/metabolismo , Receptores de Leptina/genética , Receptores de Leptina/metabolismo , Células Madre/metabolismo , Adulto Joven
8.
J Stem Cells Regen Med ; 9(1): 14-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24693204

RESUMEN

AIM: Menstrual blood derived stem cells (MenSCs) are unique stem cells that have been isolated and identified recently. The special traits of MenSCs can be related to the cell signaling pathways. In this study, in order to find out the role of Wnt signaling on MenSCs proliferation, we evaluated ß-catenin expression as a key participant in Wnt signaling pathway in response to Lithium chloride (LiCl). METHODS: MenSCs were isolated from healthy women by combining gradient density centrifugation with plastic adherence. After characterization of the isolated cells, cell proliferation of MenSCs in presence of 10-15 mM LiCl was evaluated by MTT assay. ß-catenin expression of the treated cells was examined using immunofluorescence technique. RESULTS: Flow cytometric analysis revealed that both mesenchymal and embryonic stem cell markers are expressed on menstrual blood stem cells. MTT value decreased depending on the LiCl concentration. The proliferation of MenSCs cultivated in culture media containing 15mM LiCl was approximately two fold less than those grown without LiCl (p<0.01). Moreover, nuclear accumulation of ß-catenin protein in cells treated by LiCl was greater than cells without LiCl. CONCLUSION: The MenSCs are stem cell populations with high proliferation ability and unique immunophenotyping properties. Our results demonstrated that Wnt signaling pathway regulates MenSCs proliferation via trans-localization of activated-ß-catenin protein.

9.
Cancer Invest ; 25(6): 397-404, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17882650

RESUMEN

FTIR spectroscopy is a common technique for cancer diagnosis. Applied tissue samples are heterogeneous and may be damaged in preparation procedures. Easier sampling, more available samples and also easier process with assured results would be interesting. Whole blood samples include all of these qualifications and our hypothesis was the bio-molecular changes in blood which manifest themselves in different optical signatures, detectable by FTIR spectroscopy. Noncancerous blood samples were differentiated from cancerous ones using ATR-FTIR spectroscopy and LDA classification method. Procedure was 100 percent and 90 percent accurate in prediction of cancerous or noncancerous situation for 33 known and 10 unknown samples, respectively.


Asunto(s)
Análisis Químico de la Sangre/métodos , Neoplasias/diagnóstico , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/sangre
10.
Talanta ; 72(2): 620-5, 2007 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-19071664

RESUMEN

A simple and environment friendly method was developed for determination of Malathion content of analytical and commercial insecticide samples with no special preparation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectra were characterized and 1000-2000cm(-1) region was selected for quantitative analysis utilizing partial least square (PLS) and two wavelength selection methods: (a) principal component regression (PCR) and (b) genetic algorithm (GA). Relative error of prediction (REP) was calculated in PLS, PCR-PLS and GA-PLS methods and was 3.536, 1.656 and 0.188, respectively. Proposed method is successfully applicable for quantification of Malathion in commercial grade samples and reliable results in comparison with known methods, confirms this idea.

11.
Anal Bioanal Chem ; 385(4): 708-15, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16741770

RESUMEN

A critical evaluation of the application of attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and partial least squares (PLS) to the determination of several nutritional parameters, such as the energetic value and the carbohydrate, protein and calcium contents, in commercially available yogurt samples was carried out. To this end, a highly heterogeneous population of 48 samples covering a wide range of yogurts obtained from the Spanish market was used. After correcting the spectra, hierarchical cluster analysis was performed in order to select a representative calibration set and the corresponding validation sample set. Different PLS models and several spectral windows were tested in order to evaluate their prediction capabilities for the validation set. For all nutritional parameters, with the exception of fat content, the procedure developed here provided good precision; the values obtained complied with the statutory values declared by the US FDA.


Asunto(s)
Espectroscopía Infrarroja por Transformada de Fourier/métodos , Yogur/análisis , Calcio/química , Calibración , Carbohidratos/química , Grasas/química , Proteínas/química , Yogur/clasificación
12.
Talanta ; 65(3): 824-7, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18969875

RESUMEN

In this paper, a novel and precise analytical procedure has been developed for quantitative determination of sodium percarbonate (SPC) in washing powder. The method is based on the partial least squares (PLS) treatment of data obtained by attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectrometry in wavenumber region of 1435-1342cm(-1). The statistical parameters such as R(2), RSD, SEC and SECV have been evaluated, and number of factors, number of scan and the resolution have been optimized. In this method R(2) and RSD for five independent analyses of a 0.552g per 100g solution of SPC, SEC for 10 standard samples and SECV for five validation samples were 0.998, 1.011, 0.002 and 0.039 respectively. Results obtained for six different commercial washing powders compared well with those obtained with a standard method.

13.
Analyst ; 126(8): 1432-5, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11534620

RESUMEN

A novel and precise procedure for the determination of thiourea based on vapour-generation Fourier transform infrared spectrometry is described. A 4 ml volume of 1.4% m/v iodine solution was injected into a glass vessel containing 5 ml of thiourea and 0.2 ml of 1 M sodium hydrogencarbonate solution. The CO2 evolved under these conditions was swept by a stream of nitrogen to an infrared gas cell. At 200 s after injection of the iodine solution, the vapour phase FTIR spectra were continously recorded, as a function of time, between 2500 and 2200 cm(-1), which includes the CO2 absorption band at 2350 cm(-1). From the absorbance data in the 2399-2284 cm(-1) range, integrated absorbance measurements were obtained providing transient recordings which correspond to the absorbance of CO2 in the selected wavenumber range. The method provided a limit of detection of 10 ppm of thiourea, a throughput of 14 samples h(-1) and an RSD of 1.1% for three independent analyses of a 500 ppm thiourea solution. Results obtained for a series of real samples compared well with those obtained using potentiometric titration as a reference method.

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