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  • 1
    Language: English
    In: Analytical chemistry, 19 June 2018, Vol.90(12), pp.7644-7650
    Description: Exposure to ionizing radiation can induce cellular defense mechanisms including cell activation and rapid proliferation prior to metastasis and in extreme cases can result in cell death. Herewith we apply infrared nano- and microspectroscopy combined with multidimensional data analysis to characterize the effect of ionizing radiation on single glioblastoma nuclei isolated from cells treated with 10 Gy of X-rays or 1 and 10 Gy of protons. We observed chromatin fragmentation related to the formation of apoptotic bodies following X-ray exposure. Following proton irradiation we detected evidence of a DNA conformational change (B-DNA to A-DNA transition) related to DNA repair and accompanied by an increase in protein content related to the synthesis of peptide enzymes involved in DNA repair. We also show that proton exposure can increase cholesterol and sterol ester synthesis, which are important lipids involved in the metastatic process changing the fluidity of the cellular membrane in preparation for rapid proliferation.
    Keywords: Nanotechnology ; Protons ; Brain Neoplasms -- Pathology ; Glioblastoma -- Pathology
    ISSN: 00032700
    E-ISSN: 1520-6882
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  • 2
    Language: English
    In: Angewandte Chemie International Edition, 03 January 2014, Vol.53(1), pp.169-172
    Description: DNA double strand breaks (DSBs) are deadly lesions that can lead to genetic defects and cell apoptosis. Techniques that directly detect DNA DSBs include scanning electron microscopy, atomic force microscopy (AFM), and fluorescence based approaches. While these techniques can be used to identify DSBs they provide no information on the molecular events occurring at the break. Tip‐enhanced Raman scattering (TERS) can provide molecular information from DNA at the nanoscale and in combination with AFM provides a new way to visualize and characterize the molecular structure of DSBs. DSBs result from cleavage at the 3’‐ and 5’‐bonds of deoxyribose upon exposure to UVC radiation based on the observation of POH and methyl/methylene deformation modes enhanced in the TERS spectra. It is hypothesized that strand fragments are hydrogen‐terminated at the lesion, indicating the action of free radicals during photon exposure. (DSBs) were first detected and located by atomic force microscopy, and the molecular structure of this damage was characterized with tip‐enhanced Raman scattering (see picture) using a top‐down configuration and a reflective substrate. The first experimental evidence is reported confirming that individual DSBs result from cleavage at the 3′‐ and 5′‐bonds of deoxyribose upon exposure to ultraviolet C radiation.
    Keywords: Atomic Force Microscopy ; Dna Damage ; Double Strand Breaks ; Tip‐Enhanced Raman Scattering
    ISSN: 1433-7851
    E-ISSN: 1521-3773
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  • 3
    Language: English
    In: Applied Surface Science, 15 May 2017, Vol.404, pp.168-179
    Description: An extremely important aspect of planning cancer treatment is not only the drug efficiency but also a number of challenges associated with the side effects and control of this process. That is why it is worth paying attention to the promising potential of the gold nanoparticles combined with a compound treated as a potential drug. This work presents Raman (RS), infrared absorption (IR) and surface–enhanced Raman scattering (SERS) spectroscopic investigations of –acetyl–5–methoxytryptamine (melatonin) and α–methyl– –tryptophan, regarding as anti breast cancer agents. The experimental spectroscopic analysis was supported by the quantum-chemical calculations based on the B3LYP hybrid density functional theory (DFT) at the B3LYP 6–311G(d,p) level of theory. The studied compounds were adsorbed onto two colloidal gold nanosensors synthesized by a chemical reduction method using sodium borohydride ( ) and trisodium citrate ( ), respectively. Its morphology characteristics were obtained using transmission electron microscopy (TEM). It has been suggested that the NH moiety from the aromatic ring, a well-known proton donor, causes the formation of hydrogen bonds with the negatively charged gold surface.
    Keywords: Raman Spectroscopy (Rs) ; Infrared Absorption Spectroscopy (IR) ; Surface-Enhanced Raman Scattering (Sers) ; Density Functional Theory (Dft) ; Gold Nanoparticles (Gnps) ; Tryptophan Derivatives ; Engineering
    ISSN: 0169-4332
    E-ISSN: 1873-5584
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  • 4
    Language: English
    In: Analytical chemistry, 15 July 2014, Vol.86(14), pp.6918-23
    Description: Assessment of the performance and up-to-date diagnostics of scientific equipment is one of the key components in contemporary laboratories. Most reliable checks are performed by real test experiments while varying the experimental conditions (typically, in the case of infrared spectroscopic measurements, the size of the beam aperture, the duration of the experiment, the spectral range, the scanner velocity, etc.). On the other hand, the stability of the instrument response in time is another key element of the great value. Source stability (or easy predictable temporal changes, similar to those observed in the case of synchrotron radiation-based sources working in non top-up mode), detector stability (especially in the case of liquid nitrogen- or liquid helium-cooled detectors) should be monitored. In these cases, recorded datasets (spectra) include additional variables such as time stamp when a particular spectrum was recorded (in the case of time trial experiments). A favorable approach in evaluating these data is building hyperspectral object that consist of all spectra and all additional parameters at which these spectra were recorded. Taking into account that these datasets could be considerably large in size, there is a need for the tools for semiautomatic data evaluation and information extraction. A comprehensive R archive network--the open-source R Environment--with its flexibility and growing potential, fits these requirements nicely. In this paper, examples of practical implementation of methods available in R for real-life Fourier transform infrared (FTIR) spectroscopic data problems are presented. However, this approach could easily be adopted to many various laboratory scenarios with other spectroscopic techniques.
    Keywords: Data Interpretation, Statistical ; Software ; Synchrotrons ; Spectroscopy, Fourier Transform Infrared -- Instrumentation
    ISSN: 00032700
    E-ISSN: 1520-6882
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  • 5
    Language: English
    In: Biophysical Journal, 02 February 2018, Vol.114(3), pp.429a-429a
    Keywords: Biology
    ISSN: 0006-3495
    E-ISSN: 1542-0086
    Source: ScienceDirect Journals (Elsevier)
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  • 6
    Language: English
    In: Biophysical Journal, 02 February 2018, Vol.114(3), pp.387a-387a
    Keywords: Biology
    ISSN: 0006-3495
    E-ISSN: 1542-0086
    Source: ScienceDirect Journals (Elsevier)
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  • 7
    Language: English
    In: The Journal of Physical Chemistry C, 08/17/2017, Vol.121(32), pp.17276-17288
    ISSN: 1932-7447
    E-ISSN: 1932-7455
    Source: American Chemical Society (via CrossRef)
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  • 8
    Language: English
    In: Bioelectrochemistry, Oct, 2012, Vol.87, p.114(10)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.bioelechem.2011.12.011 Byline: Wirginia KrzyAciak, Joanna Kowalska, Mariusz Kozka, Monika A. PapieA1/4, Wojciech M. Kwiatek Keywords: Proton Induced X-ray Emission (PIXE); Reactive oxygen species (ROS); Chronic venous insufficiency (CVI); Tissue iron; Blood oxidized DNA (boxDNA) Abbreviations: 8-oxo-Gua, 8-oxoguanine; API, active pharmaceutical ingredient; BCS, bathocuproine disulfonate disodium salt; BER, base-excision repair; BHT, Butylated hydroxytoluene; BSA, bovine serum albumin; CEAP, clinical state, etiology, anatomy and pathophysiology; CO, carbon monoxide; CVDs, Chronic venous diseases; CVI, chronic venous insufficiency; DETAPAC, diethylenetriaminepentaacetic acid; DMSO, Dimethyl sulfoxide; EtBr, ethidium bromide; FBS, Fetal bovine serum; FDA, fluorescein diacetate; Fpg, formamidopyrimidine DNA glycosylase; GE, General Electric; GST, glutathione S-transferase; GSV, great saphenous vein; H.sub.2O.sub.2, hydroxy peroxide; HEPES, [4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid]; HmUra, 5-hydroxymethyluracil; HO.sub.2 , hydroperoxide radical; K.sub.2EDTA, ethylenediaminetetraacetic acid dipotassium salt; KCl, potassium chloride; LMPA, low melting point agarose; MAPK, mitogen activated protein kinases; MMPs, matrix metalloproteinases; NBT, nitroblue tetrazolium; NBT-BCS, nitroblue tetrazolium-bathocuproine disulfonate disodium salt; NMPA, normal melting point agarose; O.sub.2.sup.- , superoxide anion; O.sub.2 , oxygen singlet; OH, hydroxyl radical; PBS, phosphate buffered saline; RNS, reactive nitrogen species; ROS, reactive oxygen species; SOD, superoxide dismutase activity; TBA, thiobarbituric acid; TBARs, thiobarbituric acid reactive substances; Tris THAM, tris(hydroxymethyl)aminomethane; USG, ultrasonography Abstract: Impaired venous drainage of the lower extremities determines a cascade of pathologic events leading to chronic venous disease (CVD). It is believed that the one cause of CVD is red blood cell extravasation and local iron overload that could generate free radicals and iron-dependent inflammation. The aim of this study was to investigate the relationship between: the intracellular iron deposits in varicose veins and tissue oxidative state measured by: the Proton Induced X-ray Emission Spectroscopy (Fe.sub.PIXE), (tSOD), (tGPx), (tTBARs) and (boxDNA). Patients with diagnosed CVD were qualified for surgical procedure. Entire trunk of the great saphenous vein (GSV) was extracted. Part located near medial ankle was considered competent (C) in duplex ultrasonography (USG) examination. The incompetent (I) part was extracted from GSV where USG showed incompetent valves and massive venous reflux. The difference between local tFe.sub.PIXE, tTBARS, boxDNA, tGPx, tSOD in incompetent and competent part of vein tissue was statistically significant. Intima/media ratio directly correlated with Fe.sub.PIXE C/I concentration. Iron deposition in competent vs incompetent part of vein was also related to the oxidative stress parameters (boxDNA). The findings from this pilot study suggest that Fe.sub.PIXE measurement may be useful for explaining the progression of chronic venous disease. Article History: Received 6 July 2011; Revised 18 December 2011; Accepted 30 December 2011 Article Note: (footnote) [star] Statement of authorship. WK conceived of the study, and participated in its design, carried out samples, analyzed the samples, made all experiments during the study, performed the statistical analysis and data analyses and wrote the manuscript. JK participated in study design, made the sample preparation and performed the PIXE experiment with the data analysis. MK participated in study design and collect clinical material. WMK participated in study design, conduct and subject enrollment. MAP participated in study design and made the histological sample preparation. All authors read and approved the final manuscript.
    Keywords: Glutathione Transferase -- Analysis ; Phosphotransferases -- Analysis ; Bromine Compounds -- Analysis ; Dna -- Analysis ; Superoxides -- Analysis ; Iron (Metal) -- Analysis ; Fluorescein -- Analysis ; Phosphates -- Analysis ; Carbon Monoxide -- Analysis ; Enzymology -- Analysis ; Albumin -- Analysis ; Dimethyl Sulfoxide -- Analysis ; Antioxidants (Nutrients) -- Analysis
    ISSN: 1567-5394
    Source: Cengage Learning, Inc.
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  • 9
    Language: English
    In: Biophysical Journal, 29 March 2016, Vol.110(6), pp.1304-1311
    Description: The biological influence of radiation on living matter has been studied for years; however, several questions about the detailed mechanism of radiation damage formation remain largely unanswered. Among all biomolecules exposed to radiation, DNA plays an important role because any damage to its molecular structure can affect the whole cell and may lead to chromosomal rearrangements resulting in genomic instability or cell death. To identify and characterize damage induced in the DNA sugar-phosphate backbone, in this work we performed x-ray absorption spectroscopy at the P K-edge on DNA irradiated with either UVA light or protons. By combining the experimental results with theoretical calculations, we were able to establish the types and relative ratio of lesions produced by both UVA and protons around the phosphorus atoms in DNA.
    Keywords: Biology
    ISSN: 0006-3495
    E-ISSN: 1542-0086
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  • 10
    Language: English
    In: Radiation Physics and Chemistry, 2011, Vol.80(10), pp.1104-1108
    Description: Urological cancers comprise approximately one-third of all cancers diagnosed in men worldwide and out of these, prostate cancer is the most common one ( ). Several risk factors such as age, hormone levels, environmental conditions and family history are suspected to play a role in the onset of this disease of otherwise obscure aetiology. It is therefore the medical need that drives multidisciplinary research in this field, carried out by means of various experimental and theoretical techniques. Out of many relevant factors, it is believed that sulphur can take an important part in cancer transformations. We have investigated the prostate cancer cell lines and tissues, along with selected organic and inorganic compounds used as references, by the X-ray absorption fine structure spectroscopy near the sulphur edge energy region. Particularly, the comparison of the experimental results collected during XANES measurements and theoretical calculations of electron density of states with use of the FEFF8 code and LAPW (linearised augmented plane-wave) method has been performed and in this work the first results of our studies are presented. ► Different forms of sulphur has been found in prostate cancer cells. ► FEFF8 code and LAPW method gave fairly good correspondence with the experiment. ► LAPW is able to reproduce the fine structure of the absorption spectra. ► Calculated DOS showed the influence of core atom on the shape of XANES spectra.
    Keywords: Prostate Cancer ; Sulphur ; Dos ; Xanes ; Chemistry ; Physics
    ISSN: 0969-806X
    E-ISSN: 1879-0895
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