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Introduction: Salvage radiotherapy (SRT) after radical prostatectomy for prostate cancer (PCa) is recommended as soon as PSA rises above 0.20 ng/ml, but many patients (pts) still experience local macroscopic relapse. The aim of this multicentric retrospective analysis was to evaluate the role of SRT in pts with macroscopic relapse. Materials and methods: From 2001 to 2016, 105 consecutive pts with macroscopic PCa relapse underwent SRT ± androgen deprivation therapy (ADT). Mean age was 72 years. At time of relapse, 29 pts had a PSA value < 1.0 ng/mL, 50 from 1.1 to 5, and 25 pts > 5. Before SRT, 23 pts had undergone 18F-choline PET and 15 pts pelvic MRI. Ninety-four pts had prostatic bed relapse only, and four nodal involvement. Fifty-one pts were previously submitted to first-line ADT, while 6 pts received ≥ 2 lines. Results: At a median follow-up of 52 months, 89 pts were alive, while 16 were dead. Total RT dose to macroscopic lesions was > 70 Gy in 58 pts, 66–70 Gy in 43, and < 66 Gy in 4 pts. In 72 pts, target volume encompassed only the prostatic bed with sequential boost to macroscopic site; 33 pts received prophylactic pelvic RT. Ten-year overall survival was 76.1%, while distant metastasis-free survival was 73.3%. No grade 4–5 toxicities were found. Conclusions: SRT ± ADT for macroscopic relapse showed a favorable oncological outcome supporting its important role in this scenario. Data from this series suggest that SRT may either postpone ADT or improve results over ADT alone in appropriately selected pts. [ABSTRACT FROM AUTHOR]

High-energy electron beams generated by linear accelerators, typically in the range 6 to 20 MeV, are used in small field sizes for radiotherapy of localized superficial tumors. Unshielded silicon diodes (Si-D) are commonly considered suitable detectors for relative dose measurements in small electron fields due to their high spatial resolution. Recently, a novel synthetic single crystal diamond diode (SCDD) showed suitable properties for standard electron beams and small photon beams dosimetry. The aim of the present study is twofold: to characterize 6 to 15 MeV small electron beams shaped by using commercial tubular applicators with 2, 3, 4 and 5 cm diameter and to assess the dosimetric performance under such irradiation conditions of the novel SCDD dosimeter by comparison with commercially available dosimeters, namely a Si-D and a plane–parallel ionization chamber. Percentage depth dose curves, beam profiles and output factors (OFs) were measured. A good agreement among the dosimeters was observed in all of the performed measurements. As for the tubular applicators, two main effects were evidenced: (i) OFs larger than unity were measured for a number of field sizes and energies, with values up to about 1.3, that is an output 30% greater than that obtained at the 10 × 10 cm2 reference field; (ii) for each diameter of the tubular applicator a noticeable increase of the OF values was observed with increasing beam energy, up to about 100% in the case of the smaller applicator. This OF behavior is remarkably different from what typically observed for small blocked fields having the same size and energy as those used in this study. OFs for tubular applicators depend considerably on the field size, so interpolation is unadvisable to predict the linear accelerator output for such applicators whereas reliable high-resolution detectors, as the silicon and diamond diodes used in this work allow OF measurements with uncertainties of about 1%. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to define a method to evaluate the total dose delivered to the rectum during the whole treatment course in six patients undergoing irradiation for prostate cancer using an offline definition of organ motion with images from a cone beam CT (CBCT) scanner available on a commercial linear accelerator. Methods: Patient set-up was verified using a volumetric three-dimensional CBCT scanner; 9-14 CBCT scans were obtained for each patient. Images were transferred to a commercial treatment planning system for offline organ motion analysis. The shape of the rectums were used to obtain a mean dose-volume histogram (,DVH.), which was the average of the DVHs of the rectums as they appeared in each verification CBCT. A geometric model of an average rectum (AR) was produced using the rectal contours delineated on the CBCT scans (DVHAR). To check whether the first week of treatment was representative of the whole treatment course, we evaluated the DVHs related to only the first five CBCT scans (,DVH5. and DVHAR5). Finally, the influence of a dietary protocol on the goodness of our results was considered. Results: In all six patients the original rectal DVH for the planning CT scan showed higher values than all DVHs. Conclusion: Although the application of the model to a larger set of patients is necessary to confirm this trend, reconstruction of a representative volume of the rectum throughout the entire treatment course seems feasible. [ABSTRACT FROM AUTHOR]

Polymorphonuclear cells (PMNs) are essential for the innate immune response against invading bacteria. At the same time, modulation of PMNs’ apoptosis or cell death by bacteria has emerged as a mechanism of pathogenesis. Wolbachia bacteria are Gram-negative endosymbionts of filarial nematodes and arthropods, phylogenetically related to the genera Anaplasma , Ehrlichia and Neorickettsia ( family Anaplasmataceae). Although several pathogens are known to interfere with apoptosis, there is only limited information on specific proteins that modulate this phenomenon. This is the first evidence for the anti-apoptotic activity of a surface protein of Wolbachia from filarial nematode parasites (the Wolbachia surface protein, WSP). The inhibition of apoptosis was demonstrated on purified human PMNs in vitro by different methods. TUNEL assay showed that the percentage of dead cells was reduced after stimulation with WSP; Annexin V-FITC binding assay confirmed that cell death was due mainly to apoptosis and not to necrosis. Reduced caspase-3 activity in stimulated cells also confirmed an inhibition of the apoptotic process. [ABSTRACT FROM AUTHOR]

OBJECTIVE To analyse relapse patterns, toxicity and second malignancy in patients with stage I pure germ cell testicular tumours, treated in 1970-1999. PATIENTS AND METHODS In all, 487 patients received irradiation after surgery to the infra- (407, 83.5%) or infra-and supra-diaphragmatic volumes (80, 16.5%). Treatment-related toxicity was classified according to previous criteria and fertility investigated in 246 men. Second malignancies were identified by retrospective analysis of clinical records or telephone interviews in men who no longer needed a long-term follow-up. RESULTS The 10-year overall survival was 97% (98% and 96%, respectively, for the aortic nodes only, or aortic and iliac nodes, i.e. the 'dog leg' field) and disease-free survival was 94%. Twenty-one patients relapsed (five with a true 'in-field' recurrence, nine progressed to the mediastinum, and seven had disseminated disease). Acute toxicity was mainly gastrointestinal, with 7.6% classified as grade II. In all, 73 men achieved paternity after irradiation; nine did not but had normal sperm. Second malignancies were diagnosed in 16 (3.3%) men. CONCLUSION Para-aortic irradiation may be used safely in patients with stage I seminoma and undisturbed testicular drainage, with equivalent results to the 'dog-leg' group; these unrandomized data confirm the lower toxicity and equivalent survival rates of this treatment. [ABSTRACT FROM AUTHOR]

In order to demonstrate the suggested failure of the serotoninergic system in human obesity and to evaluate the role of central serotoninergic activity in prolactin (PRL) and thyroid stimulating hormone (TSH) release in this condition, 13 euthyroid obese and 9 healthy women of normal weight were studied. A TRH test (200 µg i. v.) was performed before and after administration of fenfluramine (FF) 60 mg b. d. for 14 days. In the controls, FF did not modify the expected significant increase in PRL induced by TRH. In obese patients, however, the PRL levels was significantly increased after TRH, but the increase was less than in the controls. After FK the PRL response to TRH was larger than in the pretreatment phase, with values similar to those observed in normal subjects. In neither group FF did change the TSH-stimulating effect of TRH, but the hormonal response in obese patients was greater than in the controls. The restoration of the responsiveness of PRL to TRH after central serotoninergic stimulation confirms the hypothesis that a failure of the serotoninergic system may occur in human obesity. Since FF does not interfere with the secretory pattern of basal and stimulated TSH in normal or obese subjects, the serotoninergic system does not seem to play a major role in the control of TSH secretion. [ABSTRACT FROM AUTHOR]

The mechanisms of prolactin (PRL) unresponsiveness to repeated sulpiride (SUL) injections were investigated in 7 normal males. The experimental protocol consisted of two phases, separated by a 5 day interval. In both phases the administration of 1 mg/kg i. m. of SUL was followed 24 hours later, by the administration of the same dose of SUL together with either placebo (PL, 2 ml saline i. v.) or TRH (200 mcg i. v.). A control TRH test (200 mcg i. v.) was also performed. PRL showed a significant increase after the administration of SUL alone in both phases. Twenty-four hours later plasma PRL was still higher than the basal level and it was not significantly modified by administration of SUL+PL, or by SUL+TRH. The data seem to show that the lack of responsiveness of PRL to repeated administration of SUL is not due to refractoriness of dopaminergic receptors but probably to exhaustion of the hypophyseal PRL pool. [ABSTRACT FROM AUTHOR]

The article profiles John Somerville, an activist for world peace, human decency and planetary survival, a scholar of social philosophy and ethics and expert in Marxism, who was born in 1905 and died in 1994.

Purpose: To investigate the dosimetric properties of synthetic single crystal diamond based Schottky diodes under irradiation with therapeutic electron beams from linear accelerators. Methods: A single crystal diamond detector was fabricated and tested under 6, 8, 10, 12, and 15 MeV electron beams. The detector performances were evaluated using three types of commercial detectors as reference dosimeters: an Advanced Markus plane parallel ionization chamber, a Semiflex cylindrical ionization chamber, and a p-type silicon detector. Preirradiation, linearity with dose, dose rate dependence, output factors, lateral field profiles, and percentage depth dose profiles were investigated and discussed. Results: During preirradiation the diamond detector signal shows a weak decrease within 0.7% with respect to the plateau value and a final signal stability of 0.1% (1σ) is observed after about 5 Gy. A good linear behavior of the detector response as a function of the delivered dose is observed with deviations below ±0.3% in the dose range from 0.02 to 10 Gy. In addition, the detector response is dose rate independent, with deviations below 0.3% in the investigated dose rate range from 0.17 to 5.45 Gy/min. Percentage depth dose curves obtained from the diamond detector are in good agreement with the ones from the reference dosimeters. Lateral beam profile measurements show an overall good agreement among detectors, taking into account their respective geometrical features. The spatial resolution of solid state detectors is confirmed to be better than that of ionization chambers, being the one from the diamond detector comparable to that of the silicon diode. A good agreement within experimental uncertainties was also found in terms of output factor measurements between the diamond detector and reference dosimeters. Conclusions: The observed dosimetric properties indicate that the tested diamond detector is a suitable candidate for clinical electron beam dosimetry. [ABSTRACT FROM AUTHOR]