Environmental monitoring of low-ppb ammonia concentrations based on single-wall carbon nanotube chemiresistor gas sensors: Detection limits, response dynamics, and moisture effects

EUROSENSORS 2014, the XXVIII edition of the conference series.Under a Creative Commons license.We present single-wall carbon nanotube (SWCNT) chemiresistor gas sensor (CGS) operating at room temperature, displaying an enhanced sensitivity to NH3. Ammonia concentrations in the full range of the average [NH3] in a urban environment have been measured, and a detection limit of 3 ppb is demonstrated, which is well below the sensitivities so far reported for non- functionalized SWCNTs operating at room temperature. Different materials were tested as substrates, including cheap plastic flexible substrates. In addition to a careful preparation of the SWCNT layers, the low-ppb limit is also attained by revealing and properly tracking a fast dynamics during the desorption process. On the basis of these results a model of the CGS response vs time is proposed. When functionalized with indium-tin oxide nanoparticles, a sensitivity increase is detected, along with a remarkable selectivity towards moisture.Peer Reviewe

Kupffer cells promote lead nitrate-induced hepatocyte apoptosis via oxidative stress

BACKGROUND: Apoptosis and its modulation are crucial factors for the maintenance of liver health, allowing hepatocytes to die without provoking a potential harmful inflammatory response through a tightly controlled and regulated process. Since Kupffer cells play a key role in the maintenance of liver function, the aim of this study was to verify whether Kupffer cells are involved in the induction of liver apoptosis after i.v. injection of Pb(NO(3))(2 )likely by secretion mechanisms. RESULTS: The in vivo hepatic apoptosis, induced by Pb(NO(3))(2 )was prevented by a pre-treatment with gadolinium chloride (GdCl(3)), a Kupffer cells toxicant, that suppresses Kupffer cell activity and reduces to a half the apoptotic rate. In addition, in vivo Pb(NO(3))(2 )administration deprives hepatocytes of reduced glutathione, whereas the loss of this important oxidation-preventing agent is considerably mitigated or abolished by pre-treatment with GdCl(3). However, incubation of isolated hepatocytes and Kupffer cells and HepG2 cells with Pb(NO(3))(2 )for 24 hours induced necrotic but not apoptotic cells. Apoptosis of hepatocytes and HepG2 cells was observed only after the addition of conditioned medium obtained from Kupffer cells cultured for 24 hours with Pb(NO(3))(2), thus indicating the secretion of soluble mediators of apoptosis by Kupffer cells. Apoptosis in the HepG2 cells was observed upon 24-hours incubation of HepG2 cells with 1 mM buthionine sulfoximine, a glutathione depleting agent, thus showing that there is an oxidative apoptogenic pathway in HepG2 cells. CONCLUSION: Pb(NO(3))(2 )has, at most, a direct necrotic (but not apoptogenic) effect on hepatocytes and HepG2 cells, giving a clue about the regulatory role of Kupffer cells in the induction of liver apoptosis after a single Pb(NO(3))(2 )injection without pre-treatment with GdCl(3), probably via secreting soluble factors that trigger oxidative stress in target cells

HLA-haploidentical T cell-depleted allogeneic hematopoietic stem cell transplantation in children with fanconi anemia

Abstract We report the outcome of 12 consecutive pediatric patients with Fanconi anemia (FA) who had neither an HLA-identical sibling nor an HLA-matched unrelated donor and who were given T cell–depleted, CD34 + positively selected cells from a haploidentical related donor after a reduced-intensity, fludarabine-based conditioning regimen. Engraftment was achieved in 9 of 12 patients (75%), and the cumulative incidence of graft rejection was 17% (95% confidence interval [CI], 5% to 59%). Cumulative incidences of grades II to IV acute and chronic graft-versus-host disease were 17% (95% CI, 5% to 59%) and 35% (95% CI, 14% to 89%), respectively. The conditioning regimen was well tolerated, with no fatal regimen-related toxicity and 3 cases of grade III regimen-related toxicity. The cumulative incidence of transplant-related mortality was 17% (95% CI, 5% to 59%). The 5-year overall survival, event-free survival, and disease-free survival were 83% (95% CI, 62% to 100%), 67% (95% CI, 40% to 93%), and 83% (95% CI, 62% to 100%), respectively. These data demonstrate that a fludarabine-based conditioning regimen, followed by infusion of high doses of T cell–depleted stem cells, is able to ensure engraftment with good overall survival and disease-free survival, confirming the feasibility of haploidentical hematopoietic stem cell transplantation in FA. To the best of our knowledge, this is the largest series of hematopoietic stem cell transplantation from a haploidentical related donor in FA patients reported to date

Screening of Three Echinoderm Species as New Opportunity for Drug Discovery: Their Bioactivities and Antimicrobial Properties

Echinoderms are a renewable resource with an economic value due to their increasing demand as food and/or source of bioactive molecules exerting antitumor, antiviral, anticoagulant, antioxidant, and antimicrobial activities. In this framework, the present study is aimed at investigating the antibacterial, antioxidant, and hemolytic activities in the three Echinoderm species Echinaster sepositus, Arbacia lixula, and Sphaerechinus granularis. The sea star E. sepositus showed lysozyme-like activity (mean diameter of lysis of 13.4±0.2 mm), an antimicrobial activity against the human emerging pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and Candida famata, and a strong lytic activity (100±0.05%) towards the human red blood cells. Furthermore A. lixula and E. sepositus had the highest antioxidant activity (1792.75±233.7 and 1765.65±484.58 nmolTE/mL, resp.). From toxicological assays, it was shown that E. sepositus was not toxic towards HeLa cells and Vibrio fischeri, encouraging the exploitation of this species in the pharmaceutical field. Therefore, our findings have implications due to the ongoing explosion of antibiotic-resistant infections because of the new opportunistic pathogens and the need to discover antibacterial agents with new modes of action. Also the recorded antioxidant activity taking into account the need to find natural antioxidants useful for human health is intriguing

MicroRNA profiling of paediatric AML with FLT-ITD or MLL-rearrangements: Expression signatures and in vitro modulation of miR-221-3p and miR-222-3p with BRD4/HATs inhibitors.

Novel therapeutic strategies are needed for paediatric patients affected by Acute Myeloid Leukaemia (AML), particularly for those at high-risk for relapse. MicroRNAs (miRs) have been extensively studied as biomarkers in cancer and haematological disorders, and their expression has been correlated to the presence of recurrent molecular abnormalities, expression of oncogenes, as well as to prognosis/clinical outcome. In the present study, expression signatures of different miRs related both to presence of myeloid/lymphoid or mixed-lineage leukaemia 1 and Fms like tyrosine kinase 3 internal tandem duplications rearrangements and to the clinical outcome of paediatric patients with AML were identified. Notably, miR-221-3p and miR-222-3p resulted as a possible relapse-risk related miR. Thus, miR-221-3p and miR-222-3p expression modulation was investigated by using a Bromodomain‑containing protein 4 (BRD4) inhibitor (JQ1) and a natural compound that acts as histone acetyl transferase inhibitor (curcumin), alone or in association, in order to decrease acetylation of histone tails and potentiate the effect of BRD4 inhibition. JQ1 modulates miR-221-3p and miR-222-3p expression in AML with a synergic effect when associated with curcumin. Moreover, changes were observed in the expression of CDKN1B, a known target of miR-221-3p and miR-222-3p, increase in apoptosis and downregulation of miR-221-3p and miR-222-3p expression in CD34+ AML primary cells. Altogether, these findings suggested that several miRs expression signatures at diagnosis may be used for risk stratification and as relapse prediction biomarkers in paediatric AML outlining that epigenetic drugs, could represent a novel therapeutic strategy for high-risk paediatric patients with AML. For these epigenetic drugs, additional research for enhancing activity, bioavailability and safety is needed

Convolutional neural network based on fluorescein angiography images for retinopathy of prematurity management

Purpose: The purpose of this study was to explore the use of fluorescein angiography (FA) images in a convolutional neural network (CNN) in the management of retinopathy of prematurity (ROP).Methods: The dataset involved a total of 835 FA images of 149 eyes (90 patients), where each eye was associated with a binary outcome (57 "untreated" eyes and 92 "treated"; 308 "untreated" images, 527 "treated"). The resolution of the images was 1600 and 1200 px in 20% of cases, whereas the remaining 80% had a resolution of 640 and 480 px. All the images were resized to 640 and 480 px before training and no other preprocessing was applied. A CNN with four convolutional layers was trained on 90% of the images (n = 752) randomly chosen. The accuracy of the prediction was assessed on the remaining 10% of images (n = 83). Keras version 2.2.0 for R with Tensorflow backend version 1.11.0 was used for the analysis.Results: The validation accuracy after 100 epochs was 0.88, whereas training accuracy was 0.97. The receiver operating characteristic (ROC) presented an area under the curve (AUC) of 0.91.Conclusions: Our study showed, we believe for the first time, the applicability of artificial intelligence (CNN) technology in the ROP management driven by FA. Further studies are needed to exploit different fields of applications of this technology.Translational Relevance: This algorithm is the basis for a system that could be applied to both ROP as well as experimental oxygen induced retinopathy

Fluorescence distribution pattern allows to distinguish two species of Eugymnanthea (Leptomedusae: Eirenidae)

The auto-fluorescence patterns of the medusae observed under a fluorescent microscope with blue light excitation allows to distinguish two species of Eugymnanthea, this even when they are still attached to the hydroid as small medusa buds despite the occurrence of a sex-dependant pattern in E. japonica. A total of four distribution patterns of green fluorescence, including non-fluorescence, could be found. Three of them are found in E. japonica, called 'subumbrellar fluorescence type' except for non-fluorescence, while another type is found in E. inquilina, called 'umbrellar margin fluorescence type'. During the short life of the medusa the latter type remained invariable for up to six days in E. inquilina, while the pattern observed for up to seven days in E. japonica changed sometimes, but it always remained distinguishable from the pattern found in E. inquilina. Therefore, the fluorescence pattern is a reliable taxonomic character. Fluorescence was not found in unfertilized eggs, planulae 2–8 days old, parthenogenetically produced larvae, or in the hydroids of the two species. The auto-fluorescent and possible bioluminescent tissues of these Eugymnanthea medusae could have some unknown biological significance

Microalgae: A Promising Future

Microalgae are photosynthetic unicellular microorganisms that represent an extremely important component of the aquatic ecosystem productivity, diversity, and functioning [...

Parasites affect hemocyte functionality in the hemolymph of the invasive Atlantic blue crab Callinectes sapidus from a coastal habitat of the Salento Peninsula (SE Italy)

The blue crab Callinectes sapidus is an invasive alien species in the Mediterranean Sea. In native habitats, it suffers mortalities determined by different pathogens, including viruses, dinoflagellates, and bacteria. In invaded habitats, scant information is available on the occurrence of parasites in blue crabs, and no comparisons have been made with native brachyuran species. Here, a preliminary screening of the hemolymph of C. sapidus hemolymph as well as of three indigenous crabs (Eriphia verrucosa, Carcinus aestuarii and Pachygrapsus marmoratus), captured in the Acquatina Lagoon (Salento Peninsula, SE Italy), evidenced the presence of unidentified protozoans in more than 70% of the analyzed specimens, with a low number of suspected infections due to dinoflagellates of the genus Hematodinium. In C. sapidus, the occurrence of parasites was accompanied by a decrease of hemocyte functionality, interfering with the role of the cells in innate immunity (i.e. phagocytosis or DOPA production). More studies are necessary in order to verify the impact of this alien brachyuran on invaded ecosystems as mediated by the spread of its parasites and other pathogens

The sea urchin Paracentrotus lividus immunological response to chemical pollution exposure: the case of lindane

In the marine environment organochlorine insecticides can be broadly detected in water, sediments, and biota. These pollutants may have major ecological consequences since they may affect marine organisms and endanger organismal growth, reproduction or survival. In this study we investigated the modification of some sea urchin immunological parameters in response to subchronic lindane (gamma-HCH) exposure. Adult specimens of the sea urchin Paracentrotus lividus were exposed to two different concentrations (0.1 and 0.5 mg L-1) of lindane. After 24 and 48 h of treatment, we examined the lindane influence on coelomocytes vitality and enumeration as well on some humoral parameters. Our results showed that the presence of the pesticide affected both cellular and humoral components of the immune system. In particular, P. lividus coelomocytes vitality did not change but a decrease of the total cell number and an increase of the red cells was recorded. Haemolytic and lysozyme-like activities as well as antibacterial activity on Vibrio alginolyticus of treated animals decreased. Sea urchin immunological competence modifications might represent a tool for monitoring disease susceptibility thus providing biological criteria for the implementation of water quality standards to protect marine organism