Search results

1

Sensitivity of Vi phages III to γ-radiation in the presence of cisplatin

100%

Dabrowski T., Kwiatkowski B.

Acta Biochimica Polonica

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2005

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vol. 52

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issue 2

545-550

EN

In this study we determined Vi bacteriophage III sensitivity to native cisplatin, γ radiation (60Co) or to irradiated cisplatin, and checked the possibility of enhanced Vi bacteriophage III inactivation under combined exposure to cisplatin and γ radiation. We used highly purified phage suspensions in 0.9% NaCl solution or phosphate-buffered saline. Phage suspensions were titrated using a double agar layer method. Our study implies that survival of Vi bacteriophage III shows an exponential inverse correlation with cisplatin concentration in the incubation medium and the time of phage incubation in the presence of cisplatin. The use of irradiated cisplatin reduces phage survival in comparison with suspensions containing non-irradiated cisplatin. Irradiation of phage suspension with cisplatin causes a significant increase of phage inactivation in comparison with either treatment alone. Our results suggest that presence of cisplatin in irradiated medium enhances the radiobiological effect on Vi bacteriophages III.

2

Characterization of solvents containing CyMe4-BTPhen in selected cyclohexanone-based diluents after irradiation by accelerated electrons

88%

Distler P., Kondé J., John J., Hájková Z., Švehla J., Grüner B.

Nukleonika

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2015

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vol. 60

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issue 4

885-891

EN

Radiation stability of CyMe4-BTPhen was examined in systems with three selected cyclohexanone-based diluents. Accelerated electrons were used as a source of ionizing radiation. The CyMe4-BTPhen radiation degradation identification and characterization of the degradation products were performed by high performance liquid chromatography (HPLC) and mass spectrometry (MS) analyses. Residual concentrations of tested ligand were determined. Moreover, extraction properties of the solvents irradiated at two different doses were compared with the extraction properties of non-irradiated solvents to estimate the influence of the presence of degradation products in the organic phase.

3

Electron irradiation effects in doped high temperature superconductors YBa2Cu3−x MxOy (M = Fe, Ni; x=0; x=0:01)

88%

Sahakyan A., Nikoghosyan S., Yeritsyan H.

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vol. 6

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issue 4

797-801

EN

The influence of irradiation by electrons with an energy of 8 MeV, at dose intervals between 1013 and 2×1018el/cm2, on the properties of impurity doped, high-temperature superconductor YBa2Cu3−x MxOy (M = Fe, Ni; x=0; x=0:01) ceramics has been studied. It has been established that, as the irradiation dose is increased, the onset temperature of the transition to the superconducting state (T con), and the intergranular weak link coupling temperature between granules (T mJ), exhibit an oscillation around their initial values of approximately about 1–1.5 K. This oscillation indicates that the process of radiation defect formation in HTSC occurs in multiple stages. It was also found that the critical current (J c)decreases with an increase of the irradiation dose, and exhibits a local minimum at a dose of 8×1016el/cm2coinciding with minima for T con and T mJ at this dose. It was found that the introduction of Fe atoms to the ceramic decreases T mJ, while introducing Ni atoms decreases both T con and T mJ; it is suggested that this is a result of Ni substitution of Cu both in Cu2 plane sites and Cu1 chain sites. The introduction of Ni causes a large change in the intergranular critical current density, J c. A critical irradiation dose is obtained (2×1018)after which all HTSC parameters strongly decrease, i. e. the superconductivity of HTSC is destroyed.

4

PREPARATION OF GOLD NANOPARTICLES STABILIZED BY CHITOSAN USING IRRADIATION AND SONICATION METHODS

88%

Czechowska-Biskup R., Rokita B., Ulański P., Rosiak J. M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

18-33

EN

Gold nanoparticles (AuNPs) were synthesized, in the absence of any reducing agent, using ionizing radiation or ultrasound in aqueous solutions of chloroauric acid (HAuCl4). Chitosan (average molecular weight 158 kDa, degree of deacetylation 90 %) was used as a stabilizing agent. Both techniques yielded AuNPs which were stable in solution at RT for at least 3 months after synthesis. UV-Vis spectroscopy was used to follow substrate decay, nanoparticles formation, size of the gold core and particles stability. Hydrodynamic radii and polydispersion of the chitozan-stabilized AuNPs (i.e. the whole core-shell nanoparticles) were determined by dynamic light scattering. Zeta potential measurements were performed to assess the surface charge and stability of the particles. Influence of synthesis parameters and presence of isopropanol on the formation and properties of the products have been described and reaction mechanisms have been discussed. Radiation and sonochemical methods are demonstrated to be very efficient, fast and easy-to-control methods of synthesizing gold nanoparticles, leaving behind no unreacted reducing agent or unwanted side products, while stabilization by chitosan provides AuNPs with excellent stability and long shelf life.

5

Biomarkers used to assess radio- and chemotherapy-induced lymphocyte genome instability in a case of cerebral infarction during relapse of a testicular seminoma

75%

Gamulin M., Pastuhović A., Šantek F., Grgić M., Kopjar N.

Biomonitoring

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2014

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vol. 1

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issue 1

EN

We report a case of a testicular seminoma patient with relapse who was irradiated after acute cerebral infarction induced by cisplatin-based chemotherapy. Lymphocytic genome instability was studied using an alkaline comet assay, analysis of structural chromosome aberrations, and cytokinesis-block micronucleus assay in blood samples collected before and after PET CT scanning that preceded radiotherapy, as well as before the administration of the first and after the administration of the last fraction of 3D conformal radiation. A challengetest with hydrogen peroxide (H2O2) was performed on isolated peripheral blood lymphocytes in order to establish to what extent earlier therapies had modified the response of the patient’s DNA to external stimuli with a genotoxic chemical. Levels of primary DNA damage in lymphocytes increased after diagnostic exposure, lowered prior to administration of a conformal 3D radiotherapy, and were the highest at the end of radiotherapy. Ex vivo exposure to H2O2 caused additional lymphocyte DNA damage, which gradually increased 15 and 30 minutes after treatment. Diagnostic and therapeutic exposure to radiation caused measurable cytogenetic damage that was subjected to extensive repair. All of the obtained results point to increased genomic instability in the patient which should be taken into account in his future medical surveillance.

6

Heat load and deuterium plasma effects on SPS and WSP tungsten

75%

Vilémová M., Matějíček J., Nevrlá B., Chernyshova M., Gasior P., Kowalska-Strzeciwilk E., Jäger A.

Nukleonika

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2015

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vol. 60

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issue 2

275-283

EN

Tungsten is a prime choice for armor material in future nuclear fusion devices. For the realization of fusion, it is necessary to address issues related to the plasma–armor interactions. In this work, several types of tungsten material were studied, i.e. tungsten prepared by spark plasma sintering (SPS) and by water stabilized plasma spraying (WSP) technique. An intended surface porosity was created in the samples to model hydrogen/helium bubbles. The samples were subjected to a laser heat loading and a radiation loading of deuterium plasma to simulate edge plasma conditions of a nuclear fusion device (power density of 108 W/cm2 and 107 W/cm2, respectively, in the pulse intervals up to 200 ns). Thermally induced changes in the morphology and the damage to the studied surfaces are described. Possible consequences for the fusion device operation are pointed out.

7

Dielectric properties and specific conductivity of armenian natural clinoptilolite irradiated by electrons

75%

Yeritsyan H., Sahakyan A., Nikoghosyan S., Harutiunian V., Gevorkyan V., Grigoryan N., Hakhverdyan E., Keheyan Y., Gevorgyan R., Sargisyan H.

Open Physics

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2005

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vol. 3

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issue 4

610-622

EN

The results of dielectric properties and direct current specific electric conductivity measurements in Armenian natural clinoptilolite samples are presented. Electron irradiation with energy 8 MeV and thermal treatment of samples are performed to elucidate possible enhancement mechanisms of clinoptilolite parameters. The results are discussed on the basis of new point structural defects formation and recombination of initial ones in samples. It was shown that the irradiation dose of 3·1016 el/cm2 is critical for natural zeolite structural change, which is manifested by significant changes in dielectric properties and other characteristics. The samples subjected to high temperature heating after electron irradiation, in comparison with an unquenched one, have a significantly higher (about an order of magnitude) value of specific conductivity.

8

The effect of electron irradiation on the optical properties of the natural armenian zeolite-clinoptilolite

75%

Yeritsyan H., Harutiunian V., Gevorkyan V., Grigoryan N., Hakhverdyan E., Nikoghosyan S., Sahakyan A., Gevorgyan R., Sargisyan H., Keheyan Y.

Open Physics

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2005

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vol. 3

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issue 4

623-635

EN

Infrared (IR) absorption and luminescence in chemically and radiation-modified natural Armenian Zeolite (clinoptilolite) samples have been studied. The luminescence was studied in 390–450 nm and 620–710 nm wavelength bands, and the IR measurements were carried out in the 400–5400 cm−1 range. It is shown that the luminescence intensity depends on the content of pure clinoptilolite in the samples and, probably on the distribution of “passive” luminescence centers over Si and Al sites that became “active” under radiation or chemical treatment. The samples of electron irradiated clinoptilolite have higher luminescence intensity than the chemically and thermally treated ones. A decrease in the intensity of IR absorption bands at 3550 cm−1 and 3650 cm−1 was found after irradiation.

9

Analiza wyników samodzielnej radioterapii chorych na raka endometrium

63%

Jóźwik P., Karolewski K., Kojs Z., Jakubowicz J., Blecharz P., Urbański K.

Ginekologia Onkologiczna

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2007

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vol. 5

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issue 3

151-158

EN

Radiotherapy was used as a stand-alone therapeutic modality in 155 patients with endometrial cancer, treated at the Cracow Branch of the Center of Oncology since 1988 thru 1999. In these patients surgical excision was impossible due to far-advanced cancer (clinical stages III and IV) (n=50), severe comorbidity and poor performance status (n=105). In this patient population, 50 persons in clinical stage I received intracavitary brachytherapy, while the remaining 105 patients in clinical stages II, III and IVA received external beam irradiation followed by intracavitary brachytherapy. In the entire group (n=155), cumulative symptom-free 5 year survival rate was 51% (n=79). In relation to tumour grade, 5 year symptom- free survival rate was 70.3% in patients with well differentiated tumour, 43.5% in those with intermediate- grade tumour and only 20% in persons with poorly differentiated cancer. In patients with stage I endometrial cancer, symptom-free 5 year survival rate was 82% (n=41/50); in clinical stage II – 54.5% (30/55), in clinical stages III and IVA – 16% (8/50). Multivariate Cox analysis revealed that independent prognostic factors were clinical stage and tumour grade. Cure rates were 82%, 54.4% and 16% in clinical stages I, II and III/IVA, respectively. Symptom-free 5-year survival rates were 70.3%, 43.5% and 20% in well-differentiated, intermediate- and poorly-differentiated tumours, respectively. Severe late complications of radiotherapy (3rd and 4th degree) developed in 3.5% of patients.

PL

W latach 1988-1999 w krakowskim Oddziale Centrum Onkologii (COOK) leczono pierwotnie napromienianiem 155 chorych na raka endometrium (RE), u których niemożliwe było wykonanie zabiegu operacyjnego z powodu zbyt dużego zaawansowania raka (stopnie III i IV) (50 chorych), ciężkich chorób towarzyszących i złego stanu sprawności (105 chorych). U 50 chorych na RE w I stopniu zaawansowania zastosowano wyłącznie brachyterapię dojamową, u pozostałych 105 (stopnie II, III i IVA) brachyterapię dojamową skojarzono z uprzednią teleradioterapią. Spośród 155 chorych badanej grupy 79 pacjentek (51%) przeżyło 5 lat bez objawów nowotworu. Pięć lat bez objawów nowotworu przeżyło 70,3% chorych na wysoko zróżnicowanego, 43,5% na średnio zróżnicowanego i 20% na nisko zróżnicowanego raka. Spośród 50 chorych na raka w I stopniu zaawansowania 5 lat bez objawów choroby przeżyło 41 (82%) pacjentów, spośród 55 chorych na raka w II stopniu zaawansowania - 30 (54,5%), a spośród 50 chorych na raka w stopniach III i IVA - tylko 8 (16%). W wielocechowej analizie Coksa niezależnymi czynnikami prognostycznymi były zaawansowanie kliniczne i stopień zróżnicowania raka. Wyleczono 82% chorych na RE w I stopniu zaawansowania, 54,5% w II stopniu i tylko 16% w stopniach III i IVA. Pięć lat bez objawów nowotworu przeżyło odpowiednio 70,3%, 43,5% i 20% chorych na wysoko, średnio i nisko zróżnicowanego raka. Odległe, ciężkie powikłania (stopnie 3. i 4.) radioterapii wystąpiły jedynie u 3,5% chorych.

10

Czynniki prognostyczne u chorych na raka sromu w materiale krakowskiego oddziału Centrum Onkologii

63%

Blecharz P., Urbański K., Karolewski K., Klimek M., Pudełek J., Bieda T., Kojs E.

Ginekologia Onkologiczna

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2007

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vol. 5

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issue 1

22-28

EN

Aim of paper: Analysis of clinical material included 116 patients with vulvar cancer treated at the Cracow Division of the Centre of Oncology since 1990 thru 2003, aiming at assessment of treatment outcome and determination of prognostic factors. Material and methods: The patients’ mean age was 67 years. Microscopic study revealed highly differentiated tumour in 34.5%, medium differentiated tumour in 37.1% and non-differentiated tumour in 28.4%. In 57.7% of patients, inguinal lymph nodes were clinically unaffected, while 42.3% of patients presented with unilateral or bilateral clinically evident lymph node metastases. 54.3% of patients had non advanced disease (I and II in the TNM scale), while the remaining 45.7% had advanced disease (III and IVA degree). One hundred four patients (89.7%) underwent primary surgical treatment, while the remaining 12 (10.3%) received radiotherapy only. Probability of survival was estimated using the Kaplan-Meier method and impact of selected factors on the patients’ survival was estimated using the Cox’s proportional hazard model. Results: Cumulative 5-year survival rate was 40.5%. For TNM clinical stages I-IVA this was 60.9%, 55%, 26.5% and 10.5%, respectively. For age groups under 70 and above 70 this was 52.9% and 22.9%, respectively, while considering inguinal lymph node status N0, N1 and N2 this was 52.2%, 30.0% and 15.8%, respectively. For histological tumour grades G1, G2 and G3, 5-year survival rates were 65%, 39.5% and 12.1%, respectively. Conclusions: Statistically significant unfavourable impact on 5-year symptom-free survival rate had: age above 70 years, poorly differentiated tumour (G3), clinically evident lymph node metastases and clinical stages III and IVA. Multivariate analysis by Cox revealed that independent prognostic factors for 5-year survival were patients’ age, clinical status of inguinal lymph nodes and TNM clinical stage of vulvar cancer.

PL

Cel pracy: Analiza materiału klinicznego obejmującego 116 chorych na raka sromu leczonych w COOK w latach 1990-2003 w celu oceny wyników leczenia i czynników prognostycznych. Materiał i metody: Średni wiek chorych wynosił 67 lat. U 34,5% chorych stwierdzono raka wysokozróżnicowanego, u 37,1% średniozróżnicowanego i u 28,4% niskozróżnicowanego. U 57,7% chorych węzły chłonne pachwinowe były klinicznie niezmienione, a u 42,3% stwierdzono kliniczne przerzuty jednostronne lub obustronne. U 54,3% stwierdzono niezaawansowany proces nowotworowy (I i II wg TNM), u pozostałych 45,7% - zaawansowany (III i IVA). U 104 (89,7%) chorych zastosowano pierwotne leczenie chirurgiczne, a pozostałych 12 (10,3%) chorych leczono wyłącznie napromienianiem. Prawdopodobieństwo przeżycia oszacowano metodą Kaplana i Meiera, a dla oceny wpływu wybranych czynników na przeżycia chorych posłużono się modelem proporcjonalnego hazardu Coksa. Wyniki: Prognozowane 5-letnie przeżycia całkowite wyniosły 40,5%. Dla stopni zaawansowania I-IVA według TNM wyniosły odpowiednio: 60,9%, 55%, 26,5% i 10,5%. Dla wieku <70 lat i >70 lat było to 52,9% i 22,9%, a dla stanu klinicznego pachwinowych węzłów chłonnych - 52,2% dla N0, 30,0% dla N1 i 15,8% dla N2. Dla stopnia zróżnicowania raka G1 5-letnie przeżycia wyniosły 65%, dla G2 - 39,5% i dla G3 - 12,1%. Wnioski: Znamienny statystycznie niekorzystny wpływ na 5-letnie przeżycia całkowite miały: wiek >70 lat, niski (G3) stopień zróżnicowania raka, kliniczna obecność przerzutów w węzłach chłonnych pachwinowych oraz stopień III i IVA zaawansowania według TNM. W analizie wielocechowej metodą Coksa niezależnymi czynnikami prognostycznymi dla 5-letnich przeżyć były: wiek chorych, stan kliniczny węzłów chłonnych pachwinowych oraz zaawansowanie raka sromu wg TNM.

11

Influence of ion bombardment on the photoluminescence response of embedded CdS nanoparticles

63%

Mohanta D., Singh F., Avasthi D., Choudhury A.

Open Physics

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2006

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vol. 4

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issue 2

187-195

EN

Semiconductor nanoparticles (CdS) were fabricated by an inexpensive chemical route using polyvinyl alcohol (PVA) as the dielectric host matrix. Nano-CdS in PVA were subjected to ion irradiation (using oxygen, chlorine and gold) in the medium energy range (80–100 MeV) and under fluence variation of 1011–1013 ions/cm2. The nature of light emission was found to be drastically different in each of the three cases. Photoluminescence spectra of oxygen irradiated samples exhibit band edge emission (2.8 eV) as well as trap related emission (1.76 eV) whereas band edge emission is found to be bleached out for chlorine ion irradiated nano-CdS. The intense broad PL peaks, noticeable in the case of gold ion irradiated samples suggest superposition of the two peaks - namely, band edge emission and trap related emission. Furthermore, in the case of gold ion irradiated nano-CdS, energy shift in the PL spectra reveals variation in size distribution caused by the extra pressure effect of heavy gold ion beams. The mechanism of such a difference as a result of ion irradiation-type and ion-fluence is discussed in detail.

Refine search results

Sensitivity of Vi phages III to γ-radiation in the presence of cisplatin

Characterization of solvents containing CyMe4-BTPhen in selected cyclohexanone-based diluents after irradiation by accelerated electrons

Electron irradiation effects in doped high temperature superconductors YBa2Cu3−x MxOy (M = Fe, Ni; x=0; x=0:01)

PREPARATION OF GOLD NANOPARTICLES STABILIZED BY CHITOSAN USING IRRADIATION AND SONICATION METHODS

Biomarkers used to assess radio- and chemotherapy-induced lymphocyte genome instability in a case of cerebral infarction during relapse of a testicular seminoma

Heat load and deuterium plasma effects on SPS and WSP tungsten

Dielectric properties and specific conductivity of armenian natural clinoptilolite irradiated by electrons

The effect of electron irradiation on the optical properties of the natural armenian zeolite-clinoptilolite

Analiza wyników samodzielnej radioterapii chorych na raka endometrium

Czynniki prognostyczne u chorych na raka sromu w materiale krakowskiego oddziału Centrum Onkologii

Influence of ion bombardment on the photoluminescence response of embedded CdS nanoparticles