The innovative "Bio-Oil Spread" prevents metabolic disorders and mediates preconditioning-like cardioprotection in rats

BACKGROUND AND AIMS

Obesity is often associated with an increased cardiovascular risk. The food industry and the associated research activities focus on formulating products that are a perfect mix between an adequate fat content and health. We evaluated whether a diet enriched with Bio-Oil Spread (SD), an olive oil-based innovative food, is cardioprotective in the presence of high-fat diet (HFD)-dependent obesity.

METHODS AND RESULTS

Rats were fed for 16 weeks with normolipidic diet (ND; fat: 6.2%), HFD (fat: 42%), and ND enriched with SD (6.2% of fat + 35.8% of SD). Metabolic and anthropometric parameters were measured. Heart and liver structures were analyzed by histochemical examination. Ischemic susceptibility was evaluated on isolated and Langendorff-perfused cardiac preparations. Signaling was assessed by Western blotting. Compared to ND rats, HFD rats showed increased body weight and abdominal obesity, dyslipidemia, and impaired glucose tolerance. Morphological analyses showed that HFD is associated with heart and liver modifications (hypertrophy and steatosis, respectively), lesser evident in the SD group, together with metabolic and anthropometric alterations. In particular, IGF-1R immunodetection revealed a reduction of hypertrophy in SD heart sections. Notably, SD diet significantly reduced myocardial susceptibility against ischemia/reperfusion (I/R) with respect to HFD through the activation of survival signals (Akt, ERK1/2, and Bcl2). Systolic and diastolic performance was preserved in the SD group.

CONCLUSIONS

We suggest that SD may contribute to the prevention of metabolic disorders and cardiovascular alterations typical of severe obesity induced by an HFD, including the increased ischemic susceptibility of the myocardium. Our results pave the way to evaluate the introduction of SD in human alimentary guidelines as a strategy to reduce saturated fat intake.

The role of stereotactic ablative radiotherapy in oncological and non-oncological clinical settings: highlights from the 7th Meeting of AIRO--Young Members Working Group (AIRO Giovani)

Stereotactic ablative radiotherapy is a modern cancer treatment strategy able to deliver highly focused radiation in one or a few fractions with a radical intent in several clinical settings. Young radiation oncologists need a constant and tailored update in this context to improve patient care in daily clinical practice. A recent meeting of AIRO Giovani (AIRO--Young Members Working Group) was specifically addressed to this topic, presenting state-of-the-art knowledge, based on the latest evidence in this field. Highlights of the congress are summarized and presented in this report, including thorough contributions of the speakers dealing with the role of stereotactic ablative radiotherapy in both oncological and non-oncological diseases, divided according to anatomical and clinical scenarios: intra-cranial settings (brain malignant primary tumors, metastases, benign tumors and functional disorders) and extra-cranial indications (lung primary tumors and metastases, thoracic re-irradiation, liver, lymph node and bone metastases, prostate cancer). With literature data discussed during the congress as a background, stereotactic ablative radiotherapy has proved to be a consolidated treatment approach in specific oncological and non-oncological scenarios, as well as a promising option in other clinical settings, requiring a further prospective validation in the near future. We herein present an updated overview of stereotactic ablative radiotherapy use in the clinic.

IMRT or 3D-CRT in Glioblastoma? A Dosimetric Criterion for Patient Selection

Intensity modulated radiation therapy (IMRT) is increasingly employed in glioblastoma (GBM) treatment. The present work aimed to assess which clinical-dosimetric scenario could benefit the most from IMRT application, with respect to three-dimensional conformal radiation therapy (3D-CRT). The number of organs at risk (OARs) overlapping the planning target volume (PTV) was the parameter describing the clinical-dosimetric pattern. Based on the results, a dosimetric decision criterion to select the most appropriate treatment technique is provided. Seventeen previously irradiated patients were retrieved and re-planned with both 3D-CRT and IMRT. The prescribed dose was 60 Gy/30fx. The cases were divided into 4 groups (4 patients in each group). Each group represents the scenario where 0, 1, 2 or 3 OARs overlapped the target volume, respectively. Furthermore, in one case, 4 OARs overlapped the PTV. The techniques were compared also in terms of irradiated healthy brain tissue. The results were evaluated by paired t-test. IMRT always provided better target coverage (V95%) than 3D-CRT, regardless the clinical-dosimetric scenario: difference ranged from 0.82% ( p = 0.4) for scenario 0 to 7.8% ( p = 0.02) for scenario 3, passing through 2.54% ( p = 0.18) and 5.93% ( p = 0.08) for scenario 1 and 2, respectively. IMRT and 3D-CRT achieved comparable results in terms of dose homogeneity and conformity. Concerning the irradiation of serial-kind OARs, both techniques provided nearly identical results. A statistically significant dose reduction to the healthy brain in favor of IMRT was scored. IMRT seems a superior technique compared to 3D-CRT when there are multiple overlaps between OAR and PTV. In this scenario, IMRT allows for a better target coverage while maintaining equivalent OARs sparing and reducing healthy brain irradiation. The results from our patients dataset suggests that the overlap of three OARs can be used as a dosimetric criterion to select which patients should receive IMRT treatment.

Analysis of inter- and intrafraction accuracy of a commercial thermoplastic mask system used for image-guided particle radiation therapy

The present paper reports and discusses the results concerning both the inter- and intrafraction accuracy achievable combining the immobilization system employed in patients with head-and-neck, brain and skull base tumors with image guidance at our particle therapy center. Moreover, we investigated the influence of intrafraction time on positioning displacements. A total of 41 patients treated between January and July 2011 represented the study population. All the patients were immobilized with a tailored commercial thermoplastic head mask with standard head-neck rest (HeadSTEP(®), IT-V). Patient treatment position was verified by two orthogonal kilovoltage images acquired through a ceiling imaging robot (Siemens, Erlangen, Germany). The analysis of the applied daily corrections during the first treatment week before and after treatment delivery allowed the evaluation of the interfraction and intrafraction reproducibility of the thermoplastic mask, respectively. Concerning interfraction reproducibility, translational and rotational systematic errors (Σs) were ≤ 2.2 mm and 0.9º, respectively; translational and rotational random errors (σs) were ≤ 1.6 mm and 0.6º, respectively. Regarding the intrafraction accuracy translational and rotational Σs were ≤ 0.4 mm and 0.4º, respectively; translational and rotational σs were ≤ 0.5 mm and 0.3º, respectively. Concerning the time-intrafraction displacements correlation Pearson coefficient was 0.5 for treatment fractions with time between position checks less than or equal to median value, and 0.2 for those with time between position controls longer than the median figure. These results suggest that intrafractional patient motion is smaller than interfractional patient motion. Moreover, we can state that application of different imaging verification protocols translate into a relevant difference of accuracy for the same immobilization device. The magnitude of intrafraction displacements correlates with the time for short treatment sessions or during the early phase of long treatment delivery.

Postoperative radiotherapy (RT) with or without chemotherapy (CT) in anaplastic astrocitoma (AA) patients

e13046

Background: Although the evidence for the benefit of adding temozolamide (TMZ) to RT is limited to glioblastoma patients (pts), there is currently an increased tendency toward a combined RT + TMZ approach also in AA patients. Methods: We report in this study the survival outcome of 2 groups of pts, treated at in 2 different periods at our institution with RT after surgery ± CT. GROUP A (years 1984-2001): pts treated with surgery followed by RT; GROUP B (YEARS 2004-2009): pts treated with surgery followed by radical RT and CT according to the STUPP’s protocol; Results: Data were retrospectively collected on a consecutive series: GROUP A: 17 pts: 10 Males (M), 7 Females (F); median age 50 years (range: 31-65). Ten out of 17 pts received radical surgery and 7 subtotal surgery. All were treated with postoperative RT, median dose 5082 cGy (range: 2160-6300). The mean time between surgery and beginning of RT was 44.7 days (range 20-87). GROUP B: 17 pts: 10 M, 7 F; median age 44 years (25-72). Eleven out 17 pts received radical surgery and 6 subtotal surgery. All were treated with postoperative RT, median dose 5800 cGy (range: 4000-600). The mean time between surgery and beginning of RT was 56.3 days (range 26-111). All patients received TMZ 75 mg/mq for a median of 6 weeks (range 3-7), followed by adjuvant treatment with TMZ (200 mg/mq) for a median of 5 cycles (range 0-13). At a median follow-up of 45 mos , the median OS was 29.1 mos for the group A and 49,1 mos for the group B. Among pts treated with RT + CT after surgery, median OS was significantly longer (p= 0.03), compared to those treated with only RT after surgery. Conclusions: The limited sample sizes of 2 groups and differences such as the median RT dose and the median time between surgery and RT, does not allow any conclusion. However, our data suggest that the combined RT-CT treatment is feasible in AA pts after surgery and may possibly contribute to a prolonged control of disease. These suggestions should be explored in a prospective randomized trial.

Nitric oxide synthase-dependent "on/off" switch and apoptosis in freshwater and aestivating lungfish, Protopterus annectens: skeletal muscle versus cardiac muscle

African lungfishes (Protopterus spp.) are obligate air breathers which enter in a prolonged torpor (aestivation) in association with metabolic depression, and biochemical and morpho-functional readjustments during the dry season. During aestivation, the lungfish heart continues to pump, while the skeletal muscle stops to function but can immediately contract during arousal. Currently, nothing is known regarding the orchestration of the multilevel rearrangements occurring in myotomal and myocardial muscles during aestivation and arousal. Because of its universal role in cardio-circulatory and muscle homeostasis, nitric oxide (NO) could be involved in coordinating these stress-induced adaptations. Western blotting and immunofluorescence microscopy on cardiac and skeletal muscles of Protopterus annectens (freshwater, 6months of aestivation and 6days after arousal) showed that expression, localization and activity of the endothelial-like nitric oxide synthase (eNOS) isoform and its partners Akt and Hsp-90 are tissue-specifically modulated. During aestivation, phospho-eNOS/eNOS and phospho-Akt/Akt ratios increased in the heart but decreased in the skeletal muscle. By contrast, Hsp-90 increased in both muscle types during aestivation. TUNEL assay revealed that increased apoptosis occurred in the skeletal muscle of aestivating lungfish, but the myocardial apoptotic rate of the aestivating lungfish remained unchanged as compared with the freshwater control. Consistent with the preserved cardiac activity during aestivation, the expression of apoptosis repressor (ARC) also remained unchanged in the heart of aestivating and aroused fish as compared with the freshwater control. Contrarily, ARC expression was strongly reduced in the skeletal muscle of aestivating lungfish. On the whole, our data indicate that changes in the eNOS/NO system and cell turnover are implicated in the morpho-functional readjustments occurring in lungfish cardiac and skeletal muscle during the switch from freshwater to aestivation, and between the maintenance and arousal phases of aestivation.

Early MRI changes in glioblastoma in the period between surgery and adjuvant therapy

To investigate the increase in MRI contrast enhancement (CE) occurring in glioblastoma during the period between surgery and initiation of chemo-radiotherapy, thirty-seven patients with newly diagnosed glioblastoma were analyzed by early post-operative magnetic resonance (EPMR) imaging within three days of surgery and by pre-adjuvant magnetic resonance (PAMR) examination before adjuvant therapy. Areas of new CE were investigated by use of EPMR diffusion-weighted imaging and PAMR perfusion imaging (by arterial spin-labeling). PAMR was acquired, on average, 29.9 days later than EPMR (range 20-37 days). During this period an increased area of CE was observed for 17/37 patients. For 3/17 patients these regions were confined to areas of reduced EPMR diffusion, suggesting postsurgical infarct. For the other 14/17 patients, these areas suggested progression. For 11/17 patients the co-occurrence of hyperperfusion in PAMR perfusion suggested progression. PAMR perfusion and EPMR diffusion did not give consistent results for 3/17 patients for whom small new areas of CE were observed, presumably because of the poor spatial resolution of perfusion imaging. Before initiation of adjuvant therapy, areas of new CE of resected glioblastomas are frequently observed. Most of these suggest tumor progression, according to EPMR diffusion and PAMR perfusion criteria.

Radiosurgery with photons or protons for benign and malignant tumours of the skull base: a review

Stereotactic radiosurgery (SRS) is an important treatment option for intracranial lesions. Many studies have shown the effectiveness of photon-SRS for the treatment of skull base (SB) tumours; however, limited data are available for proton-SRS.Several photon-SRS techniques, including Gamma Knife, modified linear accelerators (Linac) and CyberKnife, have been developed and several studies have compared treatment plan characteristics between protons and photons.The principles of classical radiobiology are similar for protons and photons even though they differ in terms of physical properties and interaction with matter resulting in different dose distributions.Protons have special characteristics that allow normal tissues to be spared better than with the use of photons, although their potential clinical superiority remains to be demonstrated.A critical analysis of the fundamental radiobiological principles, dosimetric characteristics, clinical results, and toxicity of proton- and photon-SRS for SB tumours is provided and discussed with an attempt of defining the advantages and limits of each radiosurgical technique.