31 research outputs found
Effects of altered gravity induced by clinorotation on the cholinesterase activity of the non-sentient model Paramecium primaurelia (Protozoa)
Compounds known as chemical mediators, including acetylcholine, have been found not only in humans and animals, but also in living organisms, like protozoa, which lack nervous system. In Paramecium primaurelia has been described a cholinergic system, which is proven to play an important role in cell-cell interactions during its developmental cycle. In our work we investigated the effects of exposure to simulated microgravity (3D Random Positioning Machine, 56 rpm, 10-6 g) on the cholinesterase activity of the eukaryote unicellular-organism alternative-model P. primaurelia. Our results show that the exposure of P. primaurelia to microgravity for 6 h, 24 h, 48 h affects the localization and the amount of cholinesterase activity compared to cells grown under Earth gravity conditions (1 g). However, these effects are transient since P. primaurelia restores its normal cholinesterase activity after 72 h under microgravity conditions, as well as cells exposed up to 72 h to microgravity and then placed under terrestrial gravity for 48 h
Simulated microgravity induces nuclear translocation of Bax and BCL-2 in glial cultured C6 cells
Alterations in the control of apoptotic processes were observed in cells during space flight or under simulated
microgravity, the latter obtained with the 3D-Random Positioning Machine (3D-RPM).
Usually the proteins Bax and Bcl-2, act as pro- or anti-apoptotic regulators. Here we investigated the effects of
simulated microgravity obtained by the 3D-RPM on cell viability, localization and expression of Bax and Bcl-2 in
cultures of glial cancerous cells. We observed for the first time a transient cytoplasmic/nuclear translocation of
Bax and Bcl-2 triggered by changing gravity vector. Bax translocates into the nucleus after 1 h, is present
simultaneously in the cytoplasm after 6 h and comes back to the cytoplasm after 24 h. Bcl-2 translocate into the
nucleus only after 6 h and comes back to the cytoplasm after 24 h. Physiological meaning, on the regulation of
apoptotic event and possible applicative outcomes of such finding are discussed
Micronuclei induction and neurotoxic effect in C6 glioma cells exposed to low concentrations of diazinon, an organophosphorus compound
Abstract
Background: The presence of doses of diazinon far lower than
IC50 cholinesterase activity was reported in plasma of pregnant
women and newborns living in agricultural areas.
Objective: In the current study, we investigated the possibility of
neurotoxicity induction by exposing cultured gliotypic C6 cells to a
similar range of concentrations, for 24 h, at 37\ub0C.
Materials and methods: Confluent C6 cellswere exposed to
diazinon (DZN) at concentrations from 200ng/L to 0.002ng/L. The
maintenance of confluence, the induction of micronuclei and the
expression of molecules related to the cholinergic system were
verified, by morphological, biochemical and immunohistochemical
methods, in order to check the effects of the altered modulation of
the cholinergic signal on glial-like cells.
Results: The exposure to 0.002ng/L showed significant effecton
micronuclei occurrence since the exposure to 0.002ng/L, while
the inhibition on butyrylcholinesterase activity showed significant
variations starting from the exposure to 0.2ng/L up to 200ng/L.
Acetylcholinesterase activity was significantly inhibited only by
the exposure to 200ng/L. The immunohistochemical localization
of choline acetyltransferase and fibronectin showed dramatic
variation only in C6 cells exposed to 200ng/L.
Conclusion: The low doses of DZN investigated affect the
investigated features of glial-like cells, mainly starting from the
0.2ng/L dose, while the effects on AChE activity and ChAT and
fibronectin-immuorectivity were clearly exerted in cell cultures
exposed to 200ng/L. Collectively, these findings translated to the
in vivo functions of glial cells indicate that exposure to doses that
are nontoxic to adult organisms may weaken the brain defense and
functions of glial cells through an AChE-mediated mechanism
Urea affects the olfactory epithelium in developing Danio rerio: a possible role of nitric oxide
Chronic renal disease causes olfactory impairment through an unknown mechanism. Chondrichthyes, a class of vertebrates characterized by high plasma urea concentration, lack olfactory cilia and the G protein alpha subunit olfactory-type (G\u3b1olf - marker of the olfactory receptor neurons in vertebrates) in their olfactory neuroepithelium (ONE). Despite of that, there is no data in the literature about a direct action of urea on the ONE.
In this study, Danio rerio embryos were exposed to 75 mM urea concentrations from 24 to 96 hours post fertilization. The endocytosis of Neutral Red dye in the olfactory mucosa were detected in control and urea-exposed larvae as a marker of binding and internalization of the Olfactory Receptors. The presence and distribution of G\u3b1olf were investigated in the olfactory epithelium of control and urea-exposed larvae, using a commercial antibody. As Nitric oxide (NO) has important roles in the ONE and urea is known to affect its production, we evaluated, in control and urea-treated larvae, the presence of NO synthase (NOS) in the ONE using immunohistochemistry and a histoenzymatic reaction. We also exposed D. rerio larvae to a NOS-inhibitory molecule, NG-L-Nitro-Arginine (L-NArg), comparing them to the control and urea-treated fishes. Both G\u3b1olf and NOS were increased in urea- and L-NArg-treated fishes than in the control, while the Neutral Red internalization was unaffected.
Different hypotheses can be made about the effect of urea on NO production in the olfactory epithelium and, more speculatively, also about the role of NO on the G\u3b1olf synthesis/degradation. Further investigations are needed in order to understand the real effects of urea on the olfactory system of pathologically and physiologically uremic vertebrates
PET scanner clinical trial qualification for worldwide onco-hematological studies
Background: PET is currently being used in several onco-hematological clinical trials to assess therapy response and predict outcome. Reliability of PET data is assured through the use of a thorough program of clinical trial qualification of PET scanners.
Aims: To present the results of the procedure for qualifying PET scanners for Clinical Trial (CTQ) adopted by the Italian Foundation on Lymphoma (FIL), International Extra Nodal Lymphoma Research Group (IELSG) and Spanish lymphoma group (GELTAMO).
Patients and methods: Uniform and image quality NEMA/IEC phantoms acquired by local personnel with standard acquisition and reconstruction techniques were uploaded to a central server and analyzed within the CoreLab. Measured activity concentration (AC) was compared to expected values in the uniform phantom. Recovery coefficient (RC) curve was calculated in the NEMA/IEC phantom and compared to EANM guidelines.
Results: At present 76 scanners have been CTQed. The CTQ was carried out with a single iteration in 22% of sites, with two in 27%, three in 27% and ≥ 3 in 24%. The problems during CTQ were: (a) incorrect sphere filling (filled with wrong activity in five cases, with presence of bubbles in two cases and with only four sphere hot in 12 cases), (b) a measured activity different from that expected (14 cases), (c) missing data for reference activity calculation (10 cases) or CT images (3 cases), (d) difference between measured and expected activity (14 cases), (e) missing data for activity calculation (6 cases), (f) uploaded images were not in DICOM format (1 case), and (g) a wrong reconstruction algorithm was applied to the images (5 cases). Two PET sites acquired a NEMA/IEC phantom after CTQ request and one a dose calibrator source. Difference in expected versus measured AC in the uniform phantom were (1.2 ± 7%) ranging from −9.8% to 9.9%.
Conclusions: Despite the EAMN recommendation not all the PET sites have a quality program in place
Evaluation of the International Prognostic Score (IPS-7) and a Simpler Prognostic Score (IPS-3) for advanced Hodgkin lymphoma in the modern era
The international prognostic score (IPS-7) is the most commonly used risk stratification tool for advanced Hodgkin lymphoma (HL), however recent studies suggest the IPS-7 is less discriminating due to improved outcomes with contemporary therapy. We evaluated the seven variables for IPS-7 recorded at study entry for 854 patients enrolled on E2496. Univariate and multivariate Cox models were used to assess their prognostic ability for freedom from progression (FFP) and overall survival (OS). The IPS-7 remained prognostic however its prognostic range has narrowed. On multivariate analysis 2 factors (age, stage) remained significant for FFP and 3 factors (age, stage, hemoglobin) for OS. An alternative prognostic index, the IPS-3, was constructed using age, stage, and hemoglobin, which provided 4 distinct risk groups [FFP (p=0.0001) and OS (p<0.0001)]. IPS-3 outperformed the IPS-7 on risk prediction for both FFP and OS by model fit and discrimination criteria. Using reclassification calibration 18% of IPS-7 low risk patients were re-classified as intermediate risk and 13% of IPS-7 intermediate risk patients as low risk. For patients with advanced HL, the IPS-3 may provide a simpler and more accurate framework for risk assessment in the modern era. Validation of these findings in other large data sets is planned
Radio frequency system for thermal soil remediation
Radiofrequency (RF) heating of contaminated sediments is an effective and flexible method for soils remediation. Proper design of the antennas responsible of radiating into the sediments has a pivotal importance in the performances of those processes, but difficulties arise due to the fact that the radiators are buried in a lossy, time - variant and temperature - dependent medium. In this paper, a novel system for RF soil heating is presented, with a particular emphasis on the design of antennas. Both simulations and measurements of the system are presented to show the effectiveness and the viability of such systems