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1

Sulphur XANES Analysis of Cultured Human Prostate Cancer Cells

100%

Kwiatek W., Podgórczyk M., Paluszkiewicz C., Balerna A., Kisiel A.

Acta Physica Polonica A

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2008

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vol. 114

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issue 2

463-470

EN

Prostate cancer is one of the most commonly diagnosed cancers in men throughout the world. It is believed that changes to the structure of protein binding sites, altering its metabolism, may play an important role in carcinogenesis. Sulphur, often present in binding sites, can influence such changes through its chemical speciation. Hence there is a need for precise investigation of coordination environment of sulphur. X-ray absorption near edge structure spectroscopy offers such possibility. Cell culture samples offer histologically well defined areas of good homogeneity, suitable for successful and reliable X-ray absorption near edge structure analysis. This paper presents sulphur speciation data collected from three different human prostate cancer cell lines (PC-3, LNCaP and DU-145). Sulphur X-ray absorption near edge structure analysis was performed on K-edge structure. The spectra of cells were compared with those of cancerous tissue and with organic substances as well as inorganic compounds.

2

Determination of Changes in Sulphur Oxidation States in Prostate Cancer Cells

100%

Czapla J., Kwiatek W., Lekki J., Steininger R., Göttlicher J.

Acta Physica Polonica A

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2012

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vol. 121

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issue 2

497-501

EN

Prostate cancer cell lines along with selected organic and inorganic compounds used as references were studied with sulphur K-edge X-ray absorption near edge structure spectroscopy. The experiment was performed at the SUL-X beamline of the synchrotron radiation source ANKA, Karlsruhe (Germany). The sulphur was chosen for the studies because it is an essential biological element and out of many relevant factors, it is believed that it can take an important part in cancer transformations. The main goal was to determine which sulphur forms occur in prostate cancer cells and to compare these results with the ones obtained for non-cancerous cells. Therefore oxidation state of this element was analysed with S K-edge X-ray absorption near edge structure spectroscopy. The analysis of K-edge structure was done in order to investigate also the chemical structure of the elements neighbouring the central atom. The preliminary results from sulphur X-ray absorption near edge structure in prostate cancer cell line PC-3 and prostatic epithelial cell line PZ-HPV-7 (which was used as a control) show that there are various oxidation states of sulphur occurring in cells. The set of reference compounds with various sulphur oxidation states was used to establish the relation between the energy of the white line maximum and the oxidation state of sulphur. The equation of linear fit was used to compute the unknown oxidation state. In order to obtain a more detailed information the method of deconvolution of X-ray absorption near edge structure spectra was used. Experimental spectra were fitted with two Gaussian peaks and one arctangent step function. Fitting procedure was performed in Athena code and the deconvolution was used to assign the fraction of each sulphur form. The next step was to compare the results calculated for cancerous and non-cancerous cells. In this work, the first results of these studies are presented.

3

Optical Biopsy Method for Breast Cancer Diagnosis Based on Artificial Neural Network Classification οf Fluorescence Landscape Data

80%

Dramićanin T., Zeković I., Dimitrijević B., Ribar S., Dramićanin M.

Acta Physica Polonica A

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2009

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vol. 116

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issue 4

690-692

EN

Supervised self-organizing map, a type of artificial neural network, is applied for classification of human breast tissue samples utilizing data obtained from fluorescence landscape measurements. Female breast tissue samples were taken soon after the surgical resection, identified and stored at -80°C until fluorescence measurements. From fluorescence landscapes obtained in UV-VIS region spectral features showing statistically significant differences between malignant and normal samples are identified and further quantified to serve as a training input to neural network. Additional set of samples was used as a test group input to trained network in order to evaluate performance of proposed optical biopsy method. Classification sensitivity of 83.9% and specificity of 88.9% are found.

4

Development of Low-Cost Photodynamic Therapy Device

80%

Momchilov N., Bliznakova I., Borisova E., Troyanova P., Avramov L.

Acta Physica Polonica A

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2007

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vol. 112

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issue 5

1125-1130

EN

Photodiagnosis and photodynamic therapy of non-melanoma skin cancers using delta-aminolevulinic acid/protoporphyrin IX (5-ALA/PpIX) give a combined application with broadest dissemination in the current clinical practice. The problems with using of lasers as light sources are the expenses associated with the operation of these types of installations. This is why we test the capability of cheaper sources - light-emitting diodes at 405 nm for fluorescence excitation of PpIX and 635 nm for photodynamic action initiation. A LED matrix is developed in our laboratory using two types of LEDs and a combined photodiagnosis/photodynamic theory device applicable for clinical practice is built. Geometrically matrix is formed in such way that power density at 635 nm is about 40 mW/cm^2, which allow to reach treatment doses for a 15-20 min irradiation depending of the lesion size in the focus of the system. The therapeutic mode of system developed can be used also with some other photosensitizers from the porphyrins derivatives family.

5

Point Investigation Method for Cancer Changed Tissues

70%

Kłonowski Ł., Kulas Z., Bereś-Pawlik E., Rząca M., Czarnecki R., Grzebieniak Z.

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EN

In this paper we describe the method of point investigation for cancer changed tissues with application of fluorescence phenomenon. The measurements have been made using a specially constructed scanning setup and fiber sensors. The experiment with investigation of endogenous fluorescence has been made on different types of slide tissues (e.g. breast and intestine tumor or precancerous and pathological skin tissues). The obtained spectral characteristics of fluorescence, with typical intensity peaks in 480-520 nm range, have explicitly outlined healthy and pathologically changed areas. The intensity of detected fluorescence determines the evaluation of disease advancement. Moreover, the ability to scan the surface of a tissue sample with constantly moving step of scanning setup in X-Y axis allows us to present the results in a spatial distribution of fluorescence intensity.

6

Feed Forward Neural Network for Autofluorescence Imaging Classification

70%

Kulas Z., Bereś-Pawlik E., Wierzbicki J.

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issue 6

1189-1193

EN

The key elements in cancer diagnostics are the early identification and estimation of the tumor growth and its spread in order to determine the area to be operated on. The aim of our study was to develop new methods of analyzing autofluorescence images which will allow us an objective and accurate assessment of the location of a tumor and will also be helpful in determining the advancement of the disease. The proposed classification methods are based on neural network algorithms. An Olympus company endoscopic system was used for an autofluorescence intestine imaging study. The autofluorescence imaging analysis process can be divided into several main stages. The first step is preparation of a training data set. The second one involves selection of feature space, namely the selection of those features which enable distinguishing the pathologically altered areas from the healthy ones. Final stages of the analysis include pathologically changed tissue classification and diagnosis.

7

Challenges in Biology and Medicine with Synchrotron Infrared Light

51%

Dumas P., Miller L., Tobin M.

Acta Physica Polonica A

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2009

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vol. 115

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issue 2

446-454

EN

The brightness (or brilliance) of synchrotron radiation was exploited in infrared microspectrosocopy. Among application of this synchrotron-based microanalytical technique, biological and biomedical investigations, at the diffraction-limited spot size, are exhibit of an increasing interest among almost all the existing infrared beamline worldwide. This paper is presenting the main properties of such a source, coupled with an infrared microscope. Several important applications in biomedical field are reported: cancer cells studies and drug effects, human substantia nigra in Parkinson's disease, β-amyloids deposits in Alzheimer's disease.

Refine search results

Sulphur XANES Analysis of Cultured Human Prostate Cancer Cells

Determination of Changes in Sulphur Oxidation States in Prostate Cancer Cells

Optical Biopsy Method for Breast Cancer Diagnosis Based on Artificial Neural Network Classification οf Fluorescence Landscape Data

Development of Low-Cost Photodynamic Therapy Device

Point Investigation Method for Cancer Changed Tissues

Feed Forward Neural Network for Autofluorescence Imaging Classification

Challenges in Biology and Medicine with Synchrotron Infrared Light