Neutron Autoradiography Combined With UV-C Sensitization: Toward the Intracellular Localization of Boron

Our group has reported the imprint formation of biological material on polycarbonate nuclear track detectors by UV-C exposure, which is used as an approach to simultaneously visualize cell imprints and nuclear tracks coming from the boron neutron capture reaction. Considering that the cell nucleus has a higher UV-C absorption than the cytoplasm and that hematoxylin preferentially stains the nucleus, we proposed to enhance the contrast between these two main cell structures by hematoxylin staining before UV-C sensitization. In this study, several experiments were performed in order to optimize UV-C exposure parameters and chemical etching conditions for cell imprint formation using the SK-BR-3 breast cancer cell line. The proposed method improves significantly the resolution of the cell imprints. It allows clear differentiation of the nucleus from the rest of the cell, together with nuclear tracks pits. Moreover, it reduces considerably the UV-C exposure time, an important experimental issue. The proposed methodology can be applied to study the boron distribution independently from the chosen cell line and/or boron compounds.Fil: Gadan, Mario Alberto. Comisión Nacional de Energía Atómica; ArgentinaFil: Lloyd, Rodrigo. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Saint Martin, María Laura Gisela. Comisión Nacional de Energía Atómica; ArgentinaFil: Olivera, María S.. Comisión Nacional de Energía Atómica; ArgentinaFil: Policastro, Lucia Laura. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes.; ArgentinaFil: Portu, Agustina Mariana. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Nuclear Physics meets Medicine and Biology: Boron Neutron Capture Therapy

BNCT is a tumour treatment based on thermal-neutron irradiation of tissues enriched with 10B, which according to the 10B(n, )7Li reaction produces particles with high Linear Energy Transfer and short range. Since this treatment can deliver a therapeutic tumour dose sparing normal tissues, BNCT represents an alternative for diffuse tumours and metastases, which show poor response to surgery and photontherapy. In 2001 and 2003, in Pavia BNCT was applied to an isolated liver, which was infused with boron, explanted, irradiated and re-implanted. A new project was then initiated for lung tumours, developing a protocol for Boron concentration measurements and performing organ-dose Monte Carlo calculations; in parallel, radiobiology studies are ongoing to characterize the BNCT effects down to cellular level. After a brief introduction, herein we will present the main activities ongoing in Pavia including the radiobiological ones, which are under investigation not only experimentally but also theoretically, basing on a Monte Carlo code recently extended to simulate cell killing

Experimental set up for the irradiation of biological samples and nuclear track detectors with UV C

AimIn this work we present a methodology to produce an “imprint” of cells cultivated on a polycarbonate detector by exposure of the detector to UV C radiation.BackgroundThe distribution and concentration of 10B atoms in tissue samples coming from BNCT (Boron Neutron Capture Therapy) protocols can be determined through the quantification and analysis of the tracks forming its autoradiography image on a nuclear track detector. The location of boron atoms in the cell structure could be known more accurately by the simultaneous observation of the nuclear tracks and the sample image on the detector.Materials and MethodsA UV C irradiator was constructed. The irradiance was measured along the lamp direction and at different distances. Melanoma cells were cultured on polycarbonate foils, incubated with borophenylalanine, irradiated with thermal neutrons and exposed to UV C radiation. The samples were chemically attacked with a KOH solution.ResultsA uniform irradiation field was established to expose the detector foils to UV C light. Cells could be seeded on the polycarbonate surface. Both imprints from cells and nuclear tracks were obtained after chemical etching.ConclusionsIt is possible to yield cellular imprints in polycarbonate. The nuclear tracks were mostly present inside the cells, indicating a preferential boron uptake

Dietary Tryptophan Induces Opposite Health-Related Responses in the Senegalese Sole (Solea senegalensis) Reared at Low or High Stocking Densities With Implications in Disease Resistance

High rearing densities are typical conditions of both inland and onshore intensive aquaculture units. Despite obvious drawbacks, this strategy is nonetheless used to increase production profits. Such conditions inflict stress on fish, reducing their ability to cope with disease, bringing producers to adopt therapeutic strategies. In an attempt to overcome deleterious effects of chronic stress, Senegalese sole, Solea senegalensis, held at low (LD) or high density (HD) were fed tryptophan-supplemented diets with final tryptophan content at two (TRP2) or four times (TRP4) the requirement level, as well as a control and non-supplemented diet (CTRL) for 38 days. Fish were sampled at the end of the feeding trial for evaluation of their immune status, and mortalities were recorded following intra-peritoneal infection with Photobacterium damselae subsp. piscicida. Blood was collected for analysis of the hematological profile and innate immune parameters in plasma. Pituitary and hypothalamus were sampled for the assessment of neuro-endocrine-related gene expression. During the feeding trial, fish fed TRP4 and held at LD conditions presented higher mortalities, whereas fish kept at HD seemed to benefit from this dietary treatment, as disease resistance increased over that of CTRL-fed fish. In accordance, cortisol level tended to be higher in fish fed both supplemented diets at LD compared to fish fed CTRL, but was lower in fish fed TRP4 than in those fed TRP2 under HD condition. Together with lower mRNA levels of proopiomelanocortin observed with both supplementation levels, these results suggest that higher levels of tryptophan might counteract stress-induced cortisol production, thereby rendering fish better prepared to cope with disease. Data regarding sole immune status showed no clear effects of tryptophan on leucocyte numbers, but TRP4-fed fish displayed inhibited alternative complement activity (ACH50) when held at LD, as opposed to their HD counterparts whose ACH50 was higher than that of CTRLfed fish. In conclusion, while dietary tryptophan supplementation might have harmful effects in control fish, it might prove to be a promising strategy to overcome chronic stress-induced disease susceptibility in farmed Senegalese sole

EEG in bipolar disorders - a literature review

Background : Bipolar disorders are mostly genetically determined brain disorders, but primary brain dysfunctions and damage to the brain may also provoke clinical features suggesting the presence of a bipolar disorder. Aims: To review our current knowledege about standard EEG and qEEG findings in patients with bipolar I and II disorders, and discuss the value of assessing EEG and qEEG in routine clinical assesment of patients with bipolar I and II disorders. Methods: A literature search was conducted (key words: bipolar disorder, manic depression, EEG, electroencephalography) in PsychInfo PsychInfo (149 articles), Medline Ovid (510 articles) and Pubmed (524 articles) and by browsing some key psychiatric journals (Am J Psychiatry, Arch Gen Psychiatry, Biol Psychiatry, Electroencephalography, Cinical Neurophysi, Epilepsy and Behavior , J Affective dis, J Neurol, Neurosurg Psychiatry). EEG abnormality was defined as interictal spike discharge or sharp waves, epilepsy or findings suggesting epileptic disturbance including TIRDA; IRDA and small sharp spike activity. Theta-activity was only counted as abnormal if the activity was described as unilateral focal slowing of physiological rhythms by 1 Hz or more, or was unilateral with loss of reactivity of a physiological rhythm (e.g. loss of reactivity of the alfa-rhythm to eye opening or mental alerting) occuring in an awake adult not using any drugs. Results: Most studies were more than five years old and of limited quality in particular when it came to neuropsychiatric assessments and control of psychiatric comorbidity known to influence EEG patterns.. Abnormal EEG was found in a subgroup of patients with bipolar I and II disorders. Abnormality was associated with negative family history of affective disorders; female gender and higher mean age. The findings regarding qEEG characteristics and bipolar disorder were less consistent. In general terms there was asymmetric activity in frontotemporal brain regions in patients with bipolar disorders. qEEG predicted treatment response in some studies. Interpretation: Currently regular EEG is most useful for identification of abnormal brain dysfunctions in the temporal and frontal brain areas underlying bipolar symptomatology. qEEG offers promising possibilities for predicting treatment response. However, interpretation of qEEG records are still cumbersome and time-consuming limiting its use as a clinical tool. There is a great need for better designed electrophysiological studies of bipolar disorders. Good studies may provide important clinical information for the treatment of bipolar disorders

Sea Lice ( Lepeophtheirus salmonis) Infestation Reduces the Ability of Peripheral Blood Monocytic Cells (PBMCs) to Respond to and Control Replication of Salmonid Alphavirus in Atlantic Salmon ( Salmo salar L.)

Here we have studied the impact of lice (Lepeophtheirus salmonis) infestation of donor fish on the ability of isolated peripheral blood monocytes (PBMCs) to control the replication of salmonid alphavirus (SAV) ex vivo. PBMCs were collected by Percoll gradients at eight and nine weeks post copepodid infestation of Atlantic salmon post smolt. Uninfested fish were controls. PBMCs were then infected ex vivo with SAV (subtype 3), and samples were collected for analysis at two, four, and six days post virus infection. Virus titer in the supernatant was assayed in CHH-1 cells, and in addition, the relative expression of the virus structural protein E2 and selected host antiviral genes, IRF9, ISG15, Mx, and IFIT5, were assayed using real-time PCR. Significantly higher virus replication was detected in cells collected from lice-infested fish compared to controls. Higher virus titer coincided with an inability to upregulate the expression of different immune genes, IFIT5, IRF9, and Mx. These findings point towards compromised ability of PBMCs from lice-infested fish to control virus replication, and, to our knowledge, is the first report showing the direct effect of lice infestation on the interplay between viruses and immune cells. There is a possible impact on the dynamic spread of viral diseases in the aquatic environment

Defunctioning stoma and short- and long-term outcomes after low anterior resection for rectal cancer : a nationwide register–based cohort study

Purpose: A defunctioning stoma reduces the risk of symptomatic anastomotic leakage after low anterior resection for rectal cancer and mitigates the consequences when a leakage occurs, but the impact on mortality and oncological outcomes is unclear. The aim was to investigate the associations of a defunctioning stoma with short- and long-term outcomes in patients undergoing low anterior resection for rectal cancer. Methods: Data from all patients who underwent curative low anterior resection for rectal cancer between 1995 and 2010 were obtained from the Swedish Colorectal Cancer Register. A total of 4130 patients, including 2563 with and 1567 without a defunctioning stoma, were studied. Flexible parametric models were used to estimate hazard ratios for all-cause mortality, 5-year local recurrence, and distant metastatic disease in relation to the use of defunctioning stoma, adjusting for confounding factors and accounting for potential time-dependent effects. Results: During a median follow-up of 8.3 years, a total of 2169 patients died. In multivariable analysis, a relative reduction in mortality was observed up to 6 months after surgery (hazard ratio = 0.82: 95% CI 0.67–0.99), but not thereafter. After 5 years of follow-up, 4.2% (173/4130) of the patients had a local recurrence registered and 17.9% (741/4130) had developed distant metastatic disease, without difference between patients with and without defunctioning stoma. Conclusion: A defunctioning stoma is associated with a short-term reduction in all-cause mortality in patients undergoing low anterior resection for rectal cancer without any difference in long-term mortality and oncological outcomes, and should be considered as standard of care

Study of a new Automatic Reactor Power Control for the TRIGA Mark II Reactor at University of Pavia

Abstract—The installation of a new Instrumentation and Control (I&C) system for the TRIGA MARK II reactor at University of Pavia has recently been completed in order to assure a safe and continuous reactor operation for the future. The intervention involved nearly the whole I&C system and required a channelby- channel component substitution. One of the most sensitive part of the intervention concerned the Automatic Reactor Power Controller (ARPC) which permits to keep the reactor at an operator-selected power level acting on the control rod devoted to the fine regulation of system reactivity. This controller installed can be set up using different control logics: currently the system is working in relay mode. The main goal of the work presented in this paper is to set up a Proportional-Integral-Derivative (PID) configuration of the new controller installed on the TRIGA reactor of Pavia so as to optimize the response to system perturbations