[en] Highlights: •The γ-cyclodextrin- thermally reduced graphite oxide-carbon nanotube composite film was successfully synthesized. •The γCD-TRGO-CNT composite shows enhanced supramolecular recognition capability compared to the γCD-GO-CNT composite. •Sensitivity of the γCD-TRGO-CNT composite dramatically increased by a factor of two compared to the γCD-GO-CNT composite. -- Abstract: The γ-cyclodextrin–graphite oxide–carbon nanotube (γCD–GO–CNT) composite has shown the best capability and sensitivity of supramolecular recognition compared to the other two CD-GO-CNT composites (αCD-GO-CNT and βCD-GO-CNT) in our previous study. The biggest CD (γCD) was very important in the formation of the supramolecular complex and made the detection of the biomolecules easier. In this report, significantly improved supramolecular recognition capability of γCD–GO–CNT is introduced by using thermally reduced GO (TRGO), instead of typical GO. New synthesized γCD–TRGO–CNT composite film shows lower electrochemical impedance, higher carbon to oxygen atomic ratio, and larger surface area compared to the γCD–GO–CNT composite film, resulting in higher sensitivity and capability in the supramolecular recognition. The sensitivity, defined as the slope of the maximum response current versus guest molecule concentration graph, increases significantly from 4.42 to 9.44 for dopamine and from 2.21 to 4.15 for ascorbic acid. The excellent enhancement of the supramolecular recognition of the γCD–TRGO–CNT composite is attributed to TRGO. It is, therefore, concluded that it is very important to load γCD in the composite as well as to decrease the electrochemical impedance for effective electrochemical biosensors.

[en] Objective: To determine whether late genitourinary toxicity, biochemical control of prostate cancer, and dosimetric parameters in patients with large prostate glands is different from those variables in men with smaller glands after treatment with high-dose-rate brachytherapy alone (HDR-BT). Methods: From November 2003 to July 2009, 164 patients with locally advanced prostate carcinoma were sequentially enrolled and treated with 34 or 36 Gy in 4 fractions and 31.5 Gy in 3 fractions of ¹⁹²Ir HDR-BT alone. The median follow-up time was 71 months. Gland size was not considered in the selection criteria for this study. Estimates of freedom from biochemical relapse (FFbR) and late morbidity, stratified by median clinical target volume (CTV), were obtained, and differences were compared. Results: The median CTV volume was 60 cc (range, 15-208 cc). Dose–volume parameters D90 and V100 (ie, minimum dose to 90% of the prostate volume and volume receiving 100% of the prescribed isodose) achieved in patients with glands ≥60 cc were not significantly different from those with glands <60 cc (P≥.2). Nonetheless, biochemical control in patients with larger CTV was significantly higher (91% vs 78% at 6 years; P=.004). In univariate and multivariate analysis, CTV was a significant predictor for risk of biochemical relapse. This was not at the expense of an increase in either moderate (P=.6) or severe (P=.3) late genitourinary toxicity. The use of hormonal therapy was 17% lower in the large gland group (P=.01). Conclusions: Prostate gland size does not affect dosimetric parameters in HDR-BT assessed by D90 and V100. In patients with larger glands, a significantly higher biochemical control of disease was observed, with no difference in late toxicity. This improvement cannot be attributed to differences in dosimetry. Gland size should not be considered in the selection of patients for HDR-BT

[en] Recently, Daniel A. Heller et al. (Science 311, 508 (2006) demonstrated that carbon nanotubes wrapped with DNA can be placed inside living cells and detect trace amounts of harmful contaminants using near infrared light. This discovery could lead to new types of optical sensor and biomarkers at the sub cellular level. We study a simple model of this new optical bio-sensor by wrapping a piece of double-stranded DNA around the surface of single-walled carbon nanotube in much the same fashion as a ribbon wraps around a cylinder. The DNA starts out wrapping around the nanotube with a certain shape that is defined by the negative charges along its backbone. Based on a theory of exciton in carbon nanotubes and we investigated transition of DNA secondary structure from the native, right-handed B form to the alternate, left-handed Z form. We've shown that our simple model can explain the working principle of this optical bio-sensor from DNA and carbon nanotubes. (author)

[en] Radiation is a useful tool for degradation of polysaccharides, such as starch, carrageenan, alginate and chitin/chitosan. The viscosity molecular weight (Mw) of chitosan with 80% degree of deacetylation was reduced to 1.5 x 10⁵ by irradiation of 50kGy in solid phase. The solution of 10% of chitosan with Mw ca. 15 x 10⁵ was then irradiated at doses ranging 10-250kGy for further degradation and the products were supplemented into cultural media for testing of plant growth promotion effect. The results indicated that irradiated chitosan showed a strong growth-promotion effect on the increase of the length of shoot, the length of root and fresh biomass for flower plants namely Limonium latifolium, Eustoma grandiflorum and Chrysanthemum morifolium in tissue culture. The growth-promotion effect was obtained by the treatments with 50ppm of chitosan irradiated at the doses of 75-100kGy in 10% solution. The suitable concentrations of chitosan irradiated at 100kGy are ca. 100ppm for C. morifolium, 30ppm for E. grandiflorum and 40ppm for L. latifolium. In addition, our study also indicated that the survival ratio of transferred flower plantlets treated with irradiated chitosan was improved after acclimatizing for 30 days in the greenhouse. Accordingly, it is concluded that degraded chitosan obtained by radiation degradation technique is effective as a plant growth promoter as well as irradiated alginate. (author)

[en] Preparation of chitosan oligomer by radiation degradation was carried out on the gamma Co-60 source. The radiation degradation yield (G_d) of the chitosan was found to be of 1.03. The oligochitosan with 50% of dp>8 fraction was obtained by irradiating the 10% (w/v) chitosan solution in 5% acetic acid at 45 kGy for the chitosan having the initial viscometric average molecular weight, Mv=60,000. Irradiated chitosan showed higher antifungal effect than that of unirradiated one. Furthermore, the irradiated chitosan also showed the growth-promotion effect for plants. (author)

[en] This paper reports the key findings of the first Faculty of Radiation Oncology survey of trainees dealing with experiences and perceptions on work practices and choice of specialty. The survey was conducted in mid 2012 using a 37-question instrument. This was distributed by email to 159 current trainees and advertised through the Radiation Oncology Trainees Committee and other channels. There were six email reminders. Respondents were reassured that their responses were anonymous. The overall response rate was 82.8%. Gender was balanced among respondents with 67 (51.5%) being male and 63 (48.5%) being female. The most common age bracket was the 31 to 35 years range. There were similar proportions of trainee responders in each of the five years of training. A substantial number of trainees held other degrees besides medical degrees. The large majority were satisfied with radiation oncology as a career choice and with the Training Network within which they were training. Interest in oncology patients, lifestyle after training and work hours were given as the major reasons for choosing radiation oncology as a career. Nearly half of trainees were interested in undertaking some of their training in a part-time capacity and working part time as a radiation oncologist in the future. Over 70% of trainees stated they were working 36–55 clinical hours per week with additional non-clinical tasks, after-hours work and on-call duties. Nearly half of all trainees reported having one or less hours of protected time per week. Nonetheless, 40% of respondents indicated they had enough time to pursue outside interests. Radiation treatment planning and maintaining currency in general medicine were considered the most difficult aspects of training in radiation oncology. Most respondents were keen on the concept of fostering a research mentor. In terms of views on practice after completion of training, the majority were interested in pursuing a fellowship, and nearly all expressed an interest in maintaining an element of academic practice. The large majority of respondents preferred to work in an urban department as a component of their practice after training and nearly all wanted a component of public sector practice. There were only four per cent who preferred to work only within the private sector. Job availability was a concern for 94% of trainees, which far outweighed any other concerns. Trainees in radiation oncology are generally satisfied with their choice of specialty and their training. Most trainees are interested in fellowship positions, links with academia and largely public sector work in the future. Job availability for the future is their major concern.

[en] Highlights: • The hemin-GO-CNT and hemin-TRGO-CNT composites were successfully synthesized. • Redox reactions of two composites with dopamine and H₂O₂ are described. • Hemin-TRGO-CNT exhibits the highest electrochemical performance. • Sensitivities of hemin-TRGO-CNT for dopamine and H₂O₂ detection are investigated. Hemin-graphite oxide-carbon nanotube (hemin-GO-CNT) and hemin-thermally reduced graphite oxide-carbon nanotube (hemin-TRGO-CNT) composites are synthesized and investigated for the electrochemical supramolecular recognition by electron transfer between biomolecules (dopamine and hydrogen peroxide) and the composite electrodes. Redox reaction mechanisms of two composites with dopamine and hydrogen peroxide are explained in detail by using cyclic voltammetry and differential pulse voltammetry. Hemin-TRGO-CNT displays higher electrochemical detection for dopamine and hydrogen peroxide than that of hemin-GO-CNT, exhibiting enhancement of the electron transfer due to the effective immobilization of redox couple of hemin (Fe²⁺/Fe³⁺) on the TRGO-CNT surface.

[en] There is a perception that Indigenous patients are less likely to attend radiotherapy treatment. This study sought to determine if a difference in radiotherapy treatment compliance rates exists between Indigenous and non-Indigenous patients. Secondly, we aimed to ascertain which patient, disease and treatment factors affect compliance in Indigenous patients. All patients treated with radiotherapy at the Alan Walker Cancer Care Centre between March and October 2010 were analysed. Data regarding compliance rates (defined as those who chose and completed the recommended course of treatment), patient, disease and treatment factors were collected, and chi-squared and Fisher's exact tests were applied. A total of 41 courses were delivered to Indigenous patients and 224 courses delivered to non-Indigenous patients in this period. There was no difference in compliance between Indigenous and non-Indigenous patients (83% vs. 81%, P=0.75). Of the factors assessed, it was found that there was an association between toxicity grade and compliance (P=0.048). From this cohort, we cannot support the perception that Indigenous patients have overall poorer compliance with recommended radiation treatment courses. In this study, the only factor which correlated significantly with compliance was toxicity grade. It is felt that a number of factors, which negatively impact on compliance, can potentially be counteracted by a culturally sensitive model of care.

[en] The bioactivity of the PLA/d-HAp nanocomposite with 30 wt.% d-HAp was evaluated by in vitro tests and indicated that after 7 immersion days in SBF solution, PLA amorphous part was hydrolyzed and PLA crystal part was remained. The formation of apatite on the surface of the material was observed. The in vivo test results of PLA/d-HAp nanocomposite (70/30 wt/wt) on femur of dogs displayed that 3 months after grafting, the materials did not induce any osteitis, osteomyelitis or structural abnormalities. The histological and x-ray image demonstrated a growth of the bone into the material area, while osteitis and osteomyelitis were not observed. (paper)

[en] Stereotactic ablative body radiotherapy (SABR) is emerging as a non-invasive method for precision irradiation of lung tumours. However, the ideal dose/fractionation schedule is not yet known. The primary purpose of this study is to assess safety and efficacy profile of single and multi-fraction SABR in the context of pulmonary oligometastases. The TROG 13.01/ALTG 13.001 clinical trial is a multicentre unblinded randomised phase II study. Eligible patients have up to three metastases to the lung from any non-haematological malignancy, each < 5 cm in size, non-central targets, and have all primary and extrathoracic disease controlled with local therapies. Patients are randomised 1:1 to a single fraction of 28Gy versus 48Gy in four fractions of SABR. The primary objective is to assess the safety of each treatment arm, with secondary objectives including assessment of quality of life, local efficacy, resource use and costs, overall and disease free survival and time to distant failure. Outcomes will be stratified by number of metastases and origin of the primary disease (colorectal versus non-colorectal primary). Planned substudies include an assessment of the impact of online e-Learning platforms for lung SABR and assessment of the effect of SABR fractionation on the immune responses. A total of 84 patients are required to complete the study. Fractionation schedules have not yet been investigated in a randomised fashion in the setting of oligometastatic disease. Assuming the likelihood of similar clinical efficacy in both arms, the present study design allows for exploration of the hypothesis that cost implications of managing potentially increased toxicities from single fraction SABR will be outweighed by costs associated with delivering multiple-fraction SABR