171 research outputs found

    Quantum Probes for the Characterization of Nonlinear Media

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    Active optical media leading to interaction Hamiltonians of the form H=λ~ (a+a†)ζ H = \tilde{\lambda}\, (a + a^{\dagger})^{\zeta} represent a crucial resource for quantum optical technology. In this paper, we address the characterization of those nonlinear media using quantum probes, as opposed to semiclassical ones. In particular, we investigate how squeezed probes may improve individual and joint estimation of the nonlinear coupling λ~\tilde{\lambda} and of the nonlinearity order ζ\zeta. Upon using tools from quantum estimation, we show that: i) the two parameters are compatible, i.e. the may be jointly estimated without additional quantum noise; ii) the use of squeezed probes improves precision at fixed overall energy of the probe; iii) for low energy probes, squeezed vacuum represent the most convenient choice, whereas for increasing energy an optimal squeezing fraction may be determined; iv) using optimized quantum probes, the scaling of the corresponding precision with energy improves, both for individual and joint estimation of the two parameters, compared to semiclassical coherent probes. We conclude that quantum probes represent a resource to enhance precision in the characterization of nonlinear media, and foresee potential applications with current technology

    Toward the Rational Design of Lipid Gene Vectors: Shape Coupling between Lipoplex and Anionic Cellular Lipids Controls the Phase Evolution of Lipoplexes and the Efficiency of DNA Release

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    A viewpoint now emerging is that a critical factor in lipid-mediated transfection (lipofection) is the structural evolution of lipoplexes upon Interaction with anionic cellular lipids, resulting in DNA release At the early stages of interaction, We found a universal behavior of lipoplex/anionic lipid (AL) Mixtures the lipoplex structure is slightly perturbed, while the one-dimensional DNA lattice between cationic membranes is largely diluted by ALs This finding is in excellent agreement with previous Suggestions on the mechanism of DNA unbinding from lipoplexes by ALs Upon further interaction, the propensity of a given lipoplex structure to be solubilized by anionic cellular lipids strongly depends on the shape coupling between lipoplex and ALs Furthermore. we investigated the effect of the membrane charge density and a general correlation resulted the higher the membrane charge density of anionic membranes, the higher their ability to solubilize the structure of lipoplexes and to promote DNA release Lastly, the fort-nation of nonlamellar phases in lipoplex/AL mixtures is regulated by the propensity of anionic cellular lipids to adopt nonlamellar phases Remarkably. also phase transition rates and [DNA release were found to be strongly affected by the shape coupling between lipoplex and ALs. It thus seems likely that the structural and phase evolution of lipoplexes may only be meaningful in the context of specific anionic cellular membranes These results highlight the phase properties of the carrier lipid/cellular lipid Mixtures as a decisive factor for optimal DNA release and suggest a potential strategy for the rational design of efficient cationic lipid carrier

    Tailoring lipoplex composition to the lipid composition of plasma membrane: a Trojan horse for cell entry?

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    The first interaction between lipoplexes and cells is charge-mediated and not specific. Endocytosis is considered to be the main pathway for lipoplex entry. Upon interaction between lipoplexes and the plasma membrane, intermixing between lipoplex and membrane lipids is necessary for efficient endocytosis. Here we study the mechanism of the different endocytic pathways in lipid-mediated gene delivery. We show that DC-Chol-DOPE/DNA lipoplexes preferentially use a raftmediated endocytosis, while DOTAP-DOPC/DNA systems are mainly internalized by not specific fluid phase macropinocitosys. On the other hand, most efficient multicomponent lipoplexes, incorporating different lipid species in their lipid bilayer, can use multiple endocytic pathways to enter cells.Our data demonstrate that efficiency of endocytosis is regulated by shape coupling between lipoplex and membrane lipids. We suggest that such a shape-dependent coupling regulates efficient formation of endocytic vesicles thus determining the success of internalization. Our results suggest that tailoring the lipoplex lipid composition to the patchwork-like plasma membrane profile could be a successful machinery of coordinating the endocytic pathway activities and the subsequent intracellular processing

    Effects of Obesity and Thrombophilia on the Risk of Abortion in Women Undergoing In Vitro Fertilization.

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    Introduction Obesity is associated with a higher risk of abortion in women undergoing in vitro fertilization (IVF). Whether thrombophilia amplifies this risk is currently unclear. The aim of this study was to evaluate the effects of thrombophilia on the risk of abortion in obese women treated with IVF. Methods Patient characteristics, presence of inherited or acquired thrombophilia, and comorbidities were prospectively collected before the procedure in consecutive women undergoing IVF. The primary outcome was the incidence of abortion among women who achieved a clinical pregnancy. Results A total of 633 non-obese and 49 obese Caucasian women undergoing IVF were included. 204 (32%) women achieved clinical pregnancy, of whom six had an ectopic pregnancy and 63 experienced an abortion. The incidence of abortion was higher in obese women compared to non-obese women after adjusting for age (64.3% vs. 29.3%, odds ratio [OR] 4.41; 95% CI 1.41 to 13.81). Women with one or more thrombophilia were at increased risk of abortion relative to those without thrombophilia (OR 2.70; 95% CI 1.34 to 5.45), and the risk seemed to be higher with hereditary (OR 5.12; 95% CI 1.77 to 14.8) than acquired thrombophilia (OR 1.92; 95% CI 0.52 to 5.12; p for interaction 0.194). Among obese women, the presence of one or more thrombophilia seemed associated with a substantially increased risk of abortion (unadjusted OR 14.00; 95% CI 0.94 to 207.6). Conclusions Obese women undergoing IVF have a high risk of abortion which seems further amplified by the concomitant presence of thrombophilia

    Clinical, pathological and microbiological profiles of spontaneous enteropathies in growing rabbits

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    [EN] In a rabbit production facility, health monitoring for enteropathies was performed in 15 production cycles for 20 mo. For each cycle, up to a hundred 35 d old rabbits weaned the same day were randomly selected, reared in the same fattening unit, but separately from the source batch and fed with the same feed except for antimicrobial supplementation. Clinical symptoms and enteric lesions of the selected group were recorded, using two checklists with binomial response (yes/no answer to a list of 54 clinical and enteric variables). The day after weaning, one week later, at the beginning of the enteric symptoms and 4-5 d after the start of the symptoms, inocula from the small intestine and caecum of selected animals were subjected to microbiological, C. spiroforme, Eimeria oocyst and rotavirus antigen detection tests. Representative samples of E. coli and C. perfringens isolates were tested, respectively, for serotype, biotype, eae, afr/2 genes and for a, b1, b2, e, i and enterotoxin toxin genes. The answers to the clinical-pathological variables were subjected to statistical analysis with a cluster analysis programme in order to obtain homogeneous, statistically significant groups of diseased animals (clusters). Then, the clusters were statistically associated with the laboratory outcomes. The cluster to which the enterotyphlitis lesions significantly contributed was associated with E. coli detection, E. coli O103 serotype detection and C. spiroforme ("several elements" variable). C. spiroforme ("rare elements" variable) was significantly associated with a cluster, characterised by a pathological profile consisting of bloating/rumbling noise and liquid content in stomach and caecum, without enteric inflammation. C. perfringens was significantly associated with a cluster, characterised by a pathological profile consisting of dilation/liquid content of small intestine, caecal impaction and mucoid content in the colon. Eighteen out of twenty-fi ve C. perfringens strains, examined for their toxin genotypes, proved to be toxin type A, while 7 out of 25 strains showed the a and b2 toxin genes in combination. The rotavirus antigen and Eimeria oocysts were detected from healthy rabbits (specimens of the day after weaning and one week later) in about 15% of specimens examined, but their presence in the sick animals was not significantly associated with any cluster.This study was supported by a financial contribution from Avitalia, Unione Nazionale Associazioni di Produttori Avicunicoli, Forlì, Italy, as part of the programme entitled “Miglioramento della qualità, della gestione dell’offerta delle produzioni cunicole e di rafforzamento dei rapporti di filiera. Azione 4.3”. Our thanks go to breeder Leta Covelli and Dasco srl for supplying the rabbits, to our colleague Romolo Salini and to Fabrizio Agnoletti of the Istituto Zooprofilattico Sperimentale del Veneto, Trevise, ItalyBadagliacca, P.; Letizia, A.; Candeloro, L.; Di Provvido, A.; Di Gennaro, A.; Scattolini, S.; Pompei, G.... (2010). Clinical, pathological and microbiological profiles of spontaneous enteropathies in growing rabbits. World Rabbit Science. 18(4):187-198. doi:10.4995/wrs.2010.77518719818

    Predicting WNV circulation in Italy using earth observation data and extreme gradient boosting model

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    West Nile Disease (WND) is one of the most spread zoonosis in Italy and Europe caused by a vector-borne virus. Its transmission cycle is well understood, with birds acting as the primary hosts and mosquito vectors transmitting the virus to other birds, while humans and horses are occasional dead-end hosts. Identifying suitable environmental conditions across large areas containing multiple species of potential hosts and vectors can be difficult. The recent and massive availability of Earth Observation data and the continuous development of innovative Machine Learning methods can contribute to automatically identify patterns in big datasets and to make highly accurate identification of areas at risk. In this paper, we investigated the West Nile Virus (WNV) circulation in relation to Land Surface Temperature, Normalized Difference Vegetation Index and Surface Soil Moisture collected during the 160 days before the infection took place, with the aim of evaluating the predictive capacity of lagged remotely sensed variables in the identification of areas at risk for WNV circulation. WNV detection in mosquitoes, birds and horses in 2017, 2018 and 2019, has been collected from the National Information System for Animal Disease Notification. An Extreme Gradient Boosting model was trained with data from 2017 and 2018 and tested for the 2019 epidemic, predicting the spatio-temporal WNV circulation two weeks in advance with an overall accuracy of 0.84. This work lays the basis for a future early warning system that could alert public authorities when climatic and environmental conditions become favourable to the onset and spread of WNV

    Monitoring multiple myeloma by idiotype-specific peptide binders of tumor-derived exosomes.

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    Abstract Tumor-derived exosomes (TDEs) play a pivotal role in tumor establishment and progression, and are emerging biomarkers for tumor diagnosis in personalized medicine. To date, there is a lack of efficient technology platforms for exosome isolation and characterization. Multiple myeloma (MM) is an incurable B-cell malignancy due to the rapid development of drug-resistance. MM-released exosomes express the immunoglobulin B-cell receptor (Ig-BCR) of the tumor B-cells, which can be targeted by Idiotype-binding peptides (Id-peptides). In this study, we analyzed the production of MM-released exosomes in the murine 5T33MM multiple myeloma model as biomarkers of tumor growth. To this end, we selected Id-peptides by screening a phage display library using as bait the Ig-BCR expressed by 5T33MM cells. By FACS, the FITC-conjugated Id-peptides detected the MM-released exosomes in the serum of 5T33MM-engrafted mice, levels of which are correlated with tumor progression at an earlier time point compared to serum paraprotein. These results indicate that Id-peptide-based recognition of MM-released exosomes may represent a very sensitive diagnostic approach for clinical evaluation of disease progression

    ROS and Lipid Droplet accumulation induced by high glucose exposure in healthy colon and Colorectal Cancer Stem Cells

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    Lipid Droplets (LDs) are emerging as crucial players in colon cancer development and maintenance. Their expression has been associated with high tumorigenicity in Cancer Stem Cells (CSCs), so that they have been proposed as a new functional marker in Colorectal Cancer Stem Cells (CR-CSCs). They are also indirectly involved in the modulation of the tumor microenvironment through the production of pro-inflammatory molecules. There is growing evidence that a possible connection between metabolic alterations and malignant transformation exists, although the effects of nutrients, primarily glucose, on the CSC behavior are still mostly unexplored. Glucose is an essential fuel for cancer cells, and the connections with LDs in the healthy and CSC populations merit to be more deeply investigated. Here, we showed that a high glucose concentration activated the PI3K/AKT pathway and increased the expression of CD133 and CD44v6 CSC markers. Additionally, glucose was responsible for the increased amount of Reactive Oxygen Species (ROS) and LDs in both healthy and CR-CSC samples. We also investigated the gene modulations following the HG treatment and found out that the healthy cell gene profile was the most affected. Lastly, Atorvastatin, a lipid-lowering drug, induced the highest mortality on CR-CSCs without affecting the healthy counterpart
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