Craniospinal irradiation

Kraniospinalno obsevanje (CSI) zajema celotno cerebrospinalno os (od glave do tekalne vrečke) in ga uporabljamo za zdravljenje tumorjev, ki so nagnjeni k razsoju v cerebrospinalni likvor. Najpogostejša indikacija je meduloblastom, saj se v 20-30 % razširi v likvor, hkrati pa je zelo radiosenzitiven (in ga v 70 % ozdravimo z obsevanjem). CSI je zahtevno zaradi velikega in kompleksnega obsevalnega volumna in potencialnega obsevanja vseh pomembnih organov. Obsevanje zato zahteva skrbno imobilizacijo pacienta (v pediatrični populaciji pogosto s splošno anestezijo) ter izkušeno planiranje

DNA vakcine za zdravljenje raka

DNA vaccination has emerged as a promising immunotherapeutic approach against cancer due to its simplicity, stability, and safety. DNA vaccines for cancer immunotherapy are designed to deliver one or several genes encoding tumor antigens, thereby eliciting an immune response against antigens that play a central role in tumor initiation, progression or metastasis. Despite all advantages, DNA vaccines face challenges in inducing potent antigen-specific immune response in humans, which limits the successful translation from preclinical models to the clinic. Different strategies to enhance immunogenicity of DNA vaccines against tumor antigens are used, for example optimization of plasmid structure, search for new tumor antigens, development of new delivery systems and utilization of molecular adjuvants and immunomodulatory signals. These very promising approaches are employed in numerous clinical trials and hold promise for increasing the immunogenicity of cancer DNA vaccines, enhancing cancer eradication and contributing to easier translation of DNA vaccination into human clinical use.DNA vakcine predstavljajo obetaven pristop imunoterapije raka, predvsem zaradi njihove enostavnosti, stabilnosti in varnosti. DNA vakcine temeljijo na vnosu plazmidne DNA z zapisom za enega ali več tumorskih antigenov, udeleženih v nastanku, napredovanju ali zasevanju rakavih celic. Z vnosom DNA vakcine spodbudimo imunski odziv usmerjen proti tumorskemu antigenu, kar potencialno vodi do uničenja rakavih celic. Kljub številnim prednostim DNA vakcin pred klasičnimi vakcinami njihovo uporabo v humani kliniki omejuje prešibak antigen-specifični imunski odziv. Za izboljšanje imunogenosti DNA vakcin se razvoj osredotoča na optimizacijo sestave plazmidne DNA, raziskovanje novih tumorskih antigenov, razvoj novih dostavnih sistemov in sočasna uporaba adjuvantnih in imunomodulatornih molekul. Tovrstni pristopi so del številnih kliničnih raziskav na področju imunoterapije raka in predstavljajo korak bližje k izboljšanju imunogenosti DNA vakcin, učinkovitejšemu uničenju rakavih celic in lažjemu prenosu DNA vakcinacije v humano klinično prakso

Analysing mouse skin cell behaviour under a non-thermal kHz plasma jet

Plasma jets are extensively used in biomedical applications, particularly for exploring cell viability behaviour. However, many experimental parameters influence the results, including jet characteristics, secondary liquid chemistry and protocols used, slowing research progress. A specific interest of the presented research was skin cell behaviour under a non-thermal kHz plasma jet—a so-called cold plasma jet—as a topical skin treatment. Our research was focused on in vitro mouse skin cell direct plasma treatment with argon as an operating gas. The research was complemented with detailed gas-phase diagnostics and liquid-phase chemical analysis of the plasma and plasma-treated medium, respectively. The obtained results showed that direct plasma jet treatment was very destructive, leading to low cell viability. Even with short treatment times (from 35 s to 60 s), apoptosis was observed for most L929 murine fibroblasts under approximately the same conditions. This behaviour was attributed to plasma species generated from direct treatment and the types of cell lines used. Importantly, the research exposed important points that should be taken under consideration for all further research in this field: the urgent need to upgrade and standardise existing plasma treatment protocols of cell lines; to monitor gas and liquid chemistries and to standardise plasma discharge parameters

Towards treatment planning and treatment of deep-seated solid tumors by electrochemotherapy

<p>Abstract</p> <p>Background</p> <p>Electrochemotherapy treats tumors by combining specific chemotherapeutic drugs with an intracellular target and electric pulses, which increases drug uptake into the tumor cells. Electrochemotherapy has been successfully used for treatment of easily accessible superficial tumor nodules. In this paper, we present the first case of deep-seated tumor electrochemotherapy based on numerical treatment planning.</p> <p>Methods</p> <p>The aim of our study was to treat a melanoma metastasis in the thigh of a patient. Treatment planning for electrode positioning and electrical pulse parameters was performed for two different electrode configurations: one with four and another with five long needle electrodes. During the procedure, the four electrode treatment plan was adopted and the patient was treated accordingly by electrochemotherapy with bleomycin. The response to treatment was clinically and radiographically evaluated. Due to a partial response of the treated tumor, the metastasis was surgically removed after 2 months and pathological analysis was performed.</p> <p>Results</p> <p>A partial response of the tumor to electrochemotherapy was obtained. Histologically, the metastasis showed partial necrosis due to electrochemotherapy, estimated to represent 40-50% of the tumor. Based on the data obtained, we re-evaluated the electrical treatment parameters in order to correlate the treatment plan with the clinical response. Electrode positions in the numerical model were updated according to the actual positions during treatment. We compared the maximum value of the measured electric current with the current predicted by the model and good agreement was obtained. Finally, tumor coverage with an electric field above the reversible threshold was recalculated and determined to be approximately 94%. Therefore, according to the calculations, a small volume of tumor cells remained viable after electrochemotherapy, and these were sufficient for tumor regrowth.</p> <p>Conclusions</p> <p>In this, the first reported clinical case, deep-seated melanoma metastasis in the thigh of the patient was treated by electrochemotherapy, according to a treatment plan obtained by numerical modeling and optimization. Although only a partial response was obtained, the presented work demonstrates that treatment of deep-seated tumor nodules by electrochemotherapy is feasible and sets the ground for numerical treatment planning-based electrochemotherapy.</p> <p>Trial registration</p> <p>EudraCT:2008-008290-54</p

The GALAH survey: New diffuse interstellar bands found in residuals of 872,000 stellar spectra

We use more than 872,000 mid-to-high resolution (R $\sim$ 20,000) spectra of stars from the GALAH survey to discern the spectra of diffuse interstellar bands (DIBs). We use four windows with the wavelength range from 4718 to 4903, 5649 to 5873, 6481 to 6739, and 7590 to 7890 \AA, giving a total coverage of 967 \AA. We produce $\sim$400,000 spectra of interstellar medium (ISM) absorption features and correct them for radial velocities of the DIB clouds. Ultimately, we combine the 33,115 best ISM spectra into six reddening bins with a range of $0.1 \,\mathrm{mag} < E\mathrm{(B-V)} < 0.7\, \mathrm{mag}$. A total of 183 absorption features in these spectra qualify as DIBs, their fitted model parameters are summarized in a detailed catalogue. From these, 64 are not reported in the literature, among these 17 are certain, 14 are probable and 33 are possible. We find that the broad DIBs can be fitted with a multitude of narrower DIBs. Finally, we create a synthetic DIB spectrum at unit reddening which should allow us to narrow down the possible carriers of DIBs and explore the composition of the ISM and ultimately better model dust and star formation as well as to correct Galactic and extragalactic observations. The majority of certain DIBs show a significant excess of equivalent width when compared to reddening. We explain this with observed lines of sight penetrating more uniform DIB clouds compared to clumpy dust clouds.Comment: 28 pages, 15 figures, 11 tables, accepted for publication in MNRA

The K2-HERMES Survey: Age and Metallicity of the Thick Disc

Asteroseismology is a promising tool to study Galactic structure and evolution because it can probe the ages of stars. Earlier attempts comparing seismic data from the {\it Kepler} satellite with predictions from Galaxy models found that the models predicted more low-mass stars compared to the observed distribution of masses. It was unclear if the mismatch was due to inaccuracies in the Galactic models, or the unknown aspects of the selection function of the stars. Using new data from the K2 mission, which has a well-defined selection function, we find that an old metal-poor thick disc, as used in previous Galactic models, is incompatible with the asteroseismic information. We show that spectroscopic measurements of [Fe/H] and [$\alpha$/Fe] elemental abundances from the GALAH survey indicate a mean metallicity of $\log (Z/Z_{\odot})=-0.16$ for the thick disc. Here $Z$ is the effective solar-scaled metallicity, which is a function of [Fe/H] and [$\alpha$/Fe]. With the revised disc metallicities, for the first time, the theoretically predicted distribution of seismic masses show excellent agreement with the observed distribution of masses. This provides an indirect verification of the asteroseismic mass scaling relation is good to within five percent. Using an importance-sampling framework that takes the selection function into account, we fit a population synthesis model of the Galaxy to the observed seismic and spectroscopic data. Assuming the asteroseismic scaling relations are correct, we estimate the mean age of the thick disc to be about 10 Gyr, in agreement with the traditional idea of an old $\alpha$-enhanced thick disc.Comment: 21 pages, submitted to MNRA

The GALAH survey: accurate radial velocities and library of observed stellar template spectra

GALAH is a large-scale magnitude-limited southern stellar spectroscopic survey. Its second data release (GALAH DR2) provides values of stellar parameters and abundances of 23 elements for 342 682 stars (Buder et al.). Here we add a description of the public release of radial velocities with a typical accuracy of 0.1 km s−1 for 336 215 of these stars, achievable due to the large wavelength coverage, high resolving power, and good signal-to-noise ratio of the observed spectra, but also because convective motions in stellar atmosphere and gravitational redshift from the star to the observer are taken into account. In the process we derive medians of observed spectra that are nearly noiseless, as they are obtained from between 100 and 1116 observed spectra belonging to the same bin with a width of 50 K in temperature, 0.2 dex in gravity, and 0.1 dex in metallicity. Publicly released 1181 median spectra have a resolving power of 28 000 and trace the well-populated stellar types with metallicities between −0.6 and +0.3. Note that radial velocities from GALAH are an excellent match to the accuracy of velocity components along the sky plane derived by Gaia for the same stars. The level of accuracy achieved here is adequate for studies of dynamics within stellar clusters, associations, and streams in the Galaxy. So it may be relevant for studies of the distribution of dark matter.TZ, GT, and KC acknowledge financial support of ˇ the Slovenian Research Agency (research core funding No. P1-0188 and project N1-0040). TZ acknowledges the grant from the distinguished visitor programme of the RSAA at the Australian National University. JK is supported by a Discovery Project grant from the Australian Research Council (DP150104667) awarded to J. BlandHawthorn and T. Bedding. ARC acknowledges support through the Australian Research Council through grant DP160100637. LD, KF, and Y-ST are grateful for support from Australian Research Council grant DP160103747. SLM acknowledges support from the Australian Research Council through grant DE140100598. LC is the recipient of an ARC Future Fellowship (project number FT160100402). Parts of this research were conducted by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE17010001

The GALAH survey: a catalogue of carbon-enhanced stars and CEMP candidates

Swan bands - characteristic molecular absorption features of the C$_2$ molecule - are a spectroscopic signature of carbon-enhanced stars. They can also be used to identify carbon-enhanced metal-poor (CEMP) stars. The GALAH (GALactic Archaeology with Hermes) is a magnitude-limited survey of stars producing high-resolution, high signal-to-noise spectra. We used 627,708 GALAH spectra to search for carbon-enhanced stars with a supervised and unsupervised classification algorithm, relying on the imprint of the Swan bands. We identified 918 carbon-enhanced stars, including 12 already described in the literature. An unbiased selection function of the GALAH survey allows us to perform a population study of carbon-enhanced stars. Most of them are giants, out of which we find 28 CEMP candidates. A large fraction of our carbon-enhanced stars with repeated observations show variation in radial velocity, hinting that there is a large fraction of variables among them. 32 of the detected stars also show strong Lithium enhancement in their spectra.Comment: 13+5 pages, 13 figures, 1 catalog, accepted to MNRA

The GALAH survey: unresolved triple Sun-like stars discovered by the Gaia mission

The latest Gaia data release enables us to accurately identify stars that are more luminous than would be expected on the basis of their spectral type and distance. During an investigation of the 329 best solar twin candidates uncovered among the spectra acquired by the GALAH survey, we identified 64 such overluminous stars. In order to investigate their exact composition, we developed a data-driven methodology that can generate a synthetic photometric signature and spectrum of a single star. By combining multiple such synthetic stars into an unresolved binary or triple system and comparing the results to the actual photometric and spectroscopic observations, we uncovered 6 definitive triple stellar system candidates and an additional 14 potential candidates whose combined spectrum mimics the solar spectrum. Considering the volume correction factor for a magnitude-limited survey, the fraction of probable unresolved triple stars with long orbital periods is ∼2 per cent. Possible orbital configurations of the candidates were investigated using the selection and observational limits. To validate the discovered multiplicity fraction, the same procedure was used to evaluate the multiplicity fraction of other stellar types.KC, TZ, and JK acknowledge financial support of the Slovenian Research Agency (research core funding No. P1-0188 and project N1-0040). This research was partly supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. YST is supported by the NASA Hubble Fellowship grant HSTHF2-51425.001 awarded by the Space Telescope Science Institute