Évaluer l’apport dosimétrique de la tomothérapie hélicoïdale pour les cancers du sein par rapport à une radiothérapie conformationelle en technique mono-isocentrique.
Pour 23 patientes, les résultats ...dosimétriques obtenus avec la radiothérapie conformationelle en technique mono-isocentrique ne permettaient pas de satisfaire les contraintes soit des volumes prévisionnels soit des organes à risque. Une comparaison dosimétrique prospective entre radiothérapie conformationelle en technique mono-isocentrique et tomothérapie hélicoïdale a donc été réalisée.
L’utilisation de la tomothérapie hélicoïdale a montré chez ces 23 patientes, un intérêt avec une amélioration soit de l’indice de conformité, soit de celui d’homogénéité, avec cependant une augmentation des doses faibles. Sur les 23 patientes, deux avaient un pectus excavatum, cinq un antécédent d’irradiation et deux nécessitaient une irradiation bilatérale. Pour les 14 autres patientes, il s’agissait d’une association de la morphologie et/ou de l’indication d’irradiation ganglionnaire. La tomothérapie hélicoïdale a donc été préférée pour ces patientes par rapport à la radiothérapie conformationelle en technique mono-isocentrique.
La tomothérapie semble apporter une meilleure homogénéité et couverture tumorale. Cette technique d’irradiation peut se justifier en cas de situation morphologique comme le pectus excavatum ou de situation clinique complexe. Dans les autres cas, la radiothérapie conformationelle en technique mono-isocentrique reste à privilégier.
To evaluate the dosimetric contribution of helical tomotherapy for breast cancers compared with conformal radiotherapy in mono-isocentric technique.
For 23 patients, the dosimetric results in mono-isocentric 3D conformational radiotherapy did not satisfy the constraints either of target volumes nor organs at risk. A prospective dosimetric comparison between mono-isocentric 3D conformational radiotherapy and helical tomotherapy was therefore carried out.
The use of helical tomotherapy showed a benefit in these 23 patients, with either an improvement in the conformity index or homogeneity, but with an increase in low doses. Of the 23 patients, two had pectus excavatum, five had past thoracic irradiation and two required bilateral irradiation. The other 14 patients had a combination of morphology and/or indication of lymph node irradiation. For these patients, helical tomotherapy was therefore preferred to mono-isocentric 3D conformational radiotherapy.
Tomotherapy appears to provide better homogeneity and tumour coverage. This technique of irradiation may be justified in the case of morphological situations such as pectus exavatum and in complex clinical situations. In other cases, conformal radiotherapy in mono-isocentric technique remains to be favoured.
Using the facilities of the KASCADE Central Detector extensive air showers (EAS) muon arrival time distributions, observed with reference to the arrival time of the first locally registered muon, and ...their correlations with other EAS observables have been experimentally investigated. The variation of adequately defined time parameters with the distance
R
μ from the EAS axis has been measured. The experimental data enable a study of the sensitivity of such local arrival time distributions, which characterise the structure of the shower disc, to the mass composition of cosmic rays in the energy region around the knee. For that purpose, non-parametric multivariate even-by-event analyses have been performed for an estimate of the mass composition specified by three different mass groups, invoking detailed Monte Carlo simulations of the EAS development. It turns out that local muon arrival time distributions, without information on the curvature of the shower disc, display a minor sensitivity to the mass of the EAS inducing particle, at least for distances from the shower axis
R
μ<100 m. The measurements comprise a subset of all EAS events registered by KASCADE due to the observation conditions of the arrival time distributions, with a threshold of the muon energy
E
th=2.4 GeV and a minimum multiplicity
n
th for being accepted in the observed data samples. This subset is sensitive to variations of the integral EAS muon energy spectrum. By studying the event acceptance in the registered samples on basis of Monte Carlo simulations a test of the consistency of the Monte Carlo simulations with the data is enabled, comparing the results inferred from observations at different
R
μ and different
n
th values. Within the present uncertainties the results of such a test show a remarkable agreement of the experimental findings with the Monte Carlo simulations, using the QGSJET model as generator of the high-energy hadronic interactions.
Comparer l’apport de la tomothérapie hélicoïdale dans les formes complexes d’irradiation du cancer du sein et une radiothérapie conformationnelle en technique mono-isocentrique.
Trente-deux patientes ...ont été prises en charge par tomothérapie hélicoïdale pour cause d’obésité (n=10), de volumes complexes (irradiation bilatérale, traitement des aires ganglionnaires, n=15), de pectus excavatum (n=2) ou d’antécédent d’irradiation (n=5). La dose prescrite était de 50Gy dans le sein ou la paroi (premier volume anatomoclinique, CTV1), 60Gy dans le lit opératoire (deuxième volume cible anatomoclinique, CTV2) et 46Gy dans les aires ganglionnaires, avec un boost intégré, en 25 fractions. Cette dosimétrie a été comparée celle d’une radiothérapie conformationnelle en technique mono-isocentrique, de la même dose mais en mode séquentiel.
Les indices d’homogénéité du CTV1 étaient de 0,15 et de 0,36 et ceux du CTV2 de 0,07 et 0,11, respectivement pour la tomothérapie hélicoïdale et la radiothérapie conformationnelle en technique mono-isocentrique. Les indices Dice similarity coefficient du CTV1 étaient de 0,95 et de 0,73, et ceux du CTV2 de 1,25 et de 0,84. Pour ce qui concerne le poumon homolatéral, le volume recevant 20Gy (V20) était de 22,9 % pour la tomothérapie hélicoïdale et de 25,7 % pour la radiothérapie conformationnelle en technique mono-isocentrique et le volume recevant 30Gy (V30) était de 10,5 % pour la tomothérapie hélicoïdale et de 21,7 % pour la radiothérapie conformationnelle en technique mono-isocentrique. La dose maximale (Dmax) délivrée au cœur était plus élevée pour la tomothérapie hélicoïdale, 33,15Gy contre 28,7Gy pour la radiothérapie conformationnelle en technique mono-isocentrique. Les Dmax délivrées à la moelle épinière étaient respectivement de 21Gy et 19,5Gy (ET=12), enfin les normal tissue integral doses (NTID) de 265J et 150J.
La tomothérapie semble apporter une meilleure homogénéité et couverture tumorale, une diminution de la dose reçue pour le poumon homolatéral mais avec une augmentation de la NTID. Cette technique d’irradiation se justifie en cas de situation complexe. Dans les autres cas, la radiothérapie conformationnelle en technique mono-isocentrique reste à privilégier.
In a recent publication Schatz Astropart. Phys. (2003), this issue argues that unambiguous results about energy distributions of primary cosmic-ray mass groups can only be obtained from measured air ...shower observables if their
mutual correlations are explicitly taken into account. This statement is used to challenge preliminary results presented by the KASCADE Collaboration at the International Cosmic Ray Conference in Hamburg, 2001 KASCADE Collaboration, 27th ICRC, Hamburg, 2001, p. 97; KASCADE Collaboration, Invited Rapporteur and Highlight Papers of ICRC 2001, p. 240. In this comment it is argued that the criticism of Schatz does not apply to the aforementioned analysis of KASCADE data.
We present the results of an analysis of the large-scale anisotropy of cosmic rays in the PeV range. The Rayleigh formalism is applied to the right ascension distribution of extensive air showers ...measured by the KASCADE (Karlsruhe Shower Core and Array Detector) experiment. The data set contains about 10 super(8) extensive air showers in the energy range 0.7-6 PeV. No hints of anisotropy are visible in the right ascension distributions in this energy range. This accounts for all showers, as well as for subsets containing showers induced by predominantly light or heavy primary particles, respectively. Upper flux limits for Rayleigh amplitudes are determined to be between 10 super(-3) at a primary energy of 0.7 PeV and 10 super(-2) at 6 PeV.
The paper presents a proposal to describe potential water retention capacity of a given area, not necessarily the catchment basin, by a single parameter that would reflect all significant ...non-climatic physico-geographic characteristics. The potential retention capacity of forest areas in this method is estimated based on subdivision area i.e. the area of the smallest spatial unit in forestry to which a single parameter representing combined effect of physico-geographic factors of the region is attributed. In this way, characteristics assumed to be decisive for potential water retention capacity were assigned to each subdivision. Ranges of variability of each parameter were then divided into three classes (coded 1, 2 and 3) respectively to small, medium and large potential retention capacity. In the next step the codes of all parameters attributed to each of the subdivisions were summed up to obtain new value reflecting their water retention capacity. The last stage was the generation of a map presenting spatial variability of calculated index. Created map shows considerable spatial variability of the index. Subdivisions of small and of large capacity are dispersed all over the object without any tendency of combining into larger patches. Results of this study may serve as a basis to assess water relations, to establish water management priorities in plans of forest or spatial management.
W pracy zaproponowano, aby potencjalną zdolność retencyjną danego terenu, niekoniecznie zlewni, opisać za pomocą jednego parametru - miernika (wskaźnika), który ujmuje oddziaływanie wszystkich istotnych charakterystyk fizyczno-geograficznych nieklimatycznych w odniesieniu do rozpatrywanego obszaru. Podstawą szacowania wartości miernika potencjalnej zdolności retencyjnej obszarów zalesionych w tej metodzie jest wykorzystanie jako powierzchni elementarnej pododdziału, czyli najmniejszej jednostki przestrzennego podziału lasów i przydzielenie mu jednego parametru, uwzględniającego sumaryczne oddziaływanie najbardziej istotnych w danym regionie parametrów fizyczno-geograficznych na potencjalne zdolności retencyjne. Na tej podstawie każdemu z pododdziałów przyporządkowano charakterystyki, które uznano za determinujące jego potencjalną zdolność retencyjną. Następnie zakresy zmian wartości każdego z parametrów podzielono na trzy klasy, odpowiadające małej, średniej oraz dużej potencjalnej zdolności retencyjnej. Klasy te otrzymały odpowiednio kody „1", „2" i „3". W kolejnym kroku zsumowano kody wszystkich parametrów przypisanych każdemu pododdziałowi, w wyniku czego otrzymano dla każdego z nich nową wartość odzwier-ciedlającą jego zdolność retencyjną. Ostatnim etapem było wygenerowanie mapy przedstawiającej zmienność przestrzenną obliczonego miernika. Na podstawie sporządzonej mapy rozkładu miernika potencjalnej zdolności retencyjnej należy stwierdzić, że charakteryzuje się on znaczną zmiennością przestrzenną. Pododdziały o małej, jak i dużej potencjalnej zdolności retencyjnej, są rozrzucone po całym obiekcie bez wykazywania tendencji do łączenia się w większe płaty obszarowe. Wyniki przeprowadzonych badań mogą być podstawą do oceny stosunków wodnych, ustalenia hierarchii zadań w zakresie gospodarki wodnej w planach urządzania lasu czy planach zagospodarowania przestrzennego.
The dynamics of climate elements and land drainage impact on hydrologic conditions in a lakeland blind drainage area The assessment of climate dynamics and the impact of land drainage systems on ...lakeland blind drainage area was the problem studied in the paper. The research area was located based on relative stability of non-climatic physiographic characteristics and water management practices over a longer time-scale. Thus, the influence of non-climatic factors on water storage could be omitted. The study site was situated in Warmia region in the Doplyw spod Nowej Wsi catchment (27.53 km2). One of local seepage ponds called Bagna Ramuckie within the aforementioned catchment was investigated. The study covered the time period since the first half of the 19th century to the year 2005. The decisive factors affecting processes of increase and decrease of pond water surface area in considered spatial units were the trends of air temperature over the long time scale. It was indicated that natural enlargement of water surface area in the pond occurred after 40-years long period of air temperature decrease and the decline followed 20-year-long period of air temperature rise. Precipitation did not show any trends for long periods but typical cyclic changes of precipitation over a short time-scale. These pluvial cycles stimulated or destimulated processes of water surface changes additionally over short periods. The first episode of water surface decrease in the seepage pond occurred when air temperature rise trend coincided with intensive land drainage and changes in some land management patterns (the 2nd half of the 19th century). Nevertheless, during the 20th century water management practices were rather stable and did not have any impact on rise or decline of seepage pond water surface area.
Background: Epigenetic mechanisms, such as histone modification, have been implicated in the regulation of pro-inflammatory gene expression. Histone acetyltransferase (HAT) and deacetyltransferase ...(HDAC) activity alter chromatin and correlate with gene activation and repression respectively, with their dysregulation a possible causative factor in RA. HDAC inhibitors (HDIs) may have therapeutic potential in RA, through anti-inflammatory and anti-angiogenic properties. However, selective inhibition may improve clinical efficacy and safety. This study tests the hypothesis that HDAC activity contributes to RA pathogenesis and evaluates the benefits of HDAC-3 selective inhibition (HDAC-3i) or non-selective inhibition by Trichostatin A (TSA). Methods: RA patients peripheral blood mononuclear cells (PBMCs) (n = 9) were obtained prior to and 12 weeks post-etanercept treatment. HDAC, HAT, caspase-3/7 and p50/p65 NF-κB activity were measured by colorimetric and luminescent assays. Rheumatoid synovial fibroblasts (RASFs) were obtained from patients with active RA. RASF and PBMC expression of HDAC-3 and cell cycle regulator p21, were determined by FACS, western blot and immunofluorescence. Healthy control (HC) PBMCs (n = 5) were incubated +/- HDIs and stimulated with LPS/TNF/TRAIL ligands. Cytokines were assayed by ELISA, cell viability by MTT and apoptosis by annexin V-PI. Statistics by Wilcoxon and Mann-Whitney tests, presented as median or mean +/- SEM. Results: HDAC activity was significantly elevated in RA PMBCs compared with HCs (p = 0.028) and, post-etanercept treatment, HDAC activity remained unchanged. NF-κB activity was also elevated, with a trend toward HC levels post-treatment. HDAC-3 expression was similar between HC and RA PBMCs, with expression localized to the nucleus in RASFs. Both HDIs induced p21 expression. TSA dose-dependently inhibited both IL-6 and IFNγ cytokine production in HC PMBCs, whereas HDAC-3i inhibited IFNγ production only. Both HDIs increased apoptotic activity and also sensitized PBMCs to TNF-related apoptosis inducing ligand (TRAIL) induced apoptosis. Conclusions: HDAC activity is dysregulated in RA patient PBMCs and may represent a novel therapeutic target, as activity is unchanged post anti-TNF treatment. NF-κB regulates a subset of pro-inflammatory genes; NF-κB (p50/p65) activity is increased in RA and is reduced post-treatment, however reduction to HC baseline could be beneficial. Both HDIs reduced NF-κB (p65) activity, possibly through increased apoptotic activity. HDAC-3 may not be the cause of dysregulation as expression was unchanged in RA PBMCs. However, both HDIs induce p21 in RASFs, thereby promoting differentiation rather than proliferation. TRAIL is increased in RA synovial fluid, compared with OA and both HDIs may have the benefit of sensitizing RASFs to TRAIL-induced apoptosis. Though TSA is more potent, the HDAC-3i could potentially be more useful as a combinational treatment for RA due to its lesser effect on the inhibition of cytokine production. Disclosure statement: All authors have declared no conflicts of interest.
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