117 research outputs found
Catalysis in Supramolecular Systems: the Case of Gel Phases
Supramolecular gels are a fascinating class of materials, originated by the self-assembly of low molecular weight molecules. Underpinned by non-covalent interactions, they find application in a diverse range of fields. Among these, supramolecular gels can be considered as organized, non-conventional reaction media, able to influence reactivity in a radically different way, compared with what happens in solution. This short review will focus on this aspect, covering literature from 2010 onwards, addressing the application of supramolecular gels as reaction media. In particular, in the first section we explore organocatalytic reactions in gel phase, with wide synthetic relevance, such as aldol and Mannich reactions as well as Friedel Crafts or ester hydrolysis processes. Subsequently, focus is laid on metal-catalysed reactions, among which relevance is given to widely used reactions like cross-coupling and click reactions. Then, the final sections describe the use of supramolecular gels as reaction media for photo- and biocatalysed processes
Preliminary studies on red palm weevil as potential risk for palm trees in mediterranean basin
The impacts of insect invasive species on human health and on agricutlture have attracted worldwide attention. However, researchers and policymakers rarely directly address the connection between invasive species and loss in natual and cultural heritages. Various attempts have been made to address the plants that are affected by invasive species but the links between these and loss in naturla biodiversity and heritage in botanical and historical gardens are largely lacking in the literature.
We report a study on the Red Palm Weevil (RPW), Rhynchophorous ferrugineus (Oliv.) (Fig. 1) (Coleoptera, Curculionidae) which is the most important pest of the palm date trees in many countries. RPW is a large polyphagous insect native to southern Asia and Melanesia and one of the most important pests of several palm species. It reached Italy in 2004 and now is wide spread in Sicily but also in almost all Mediterranean, through Phoenix dactylifera and P. canariensis (Fig. 2).
In Europe for the first time was established the RPW-P. canariensis interaction. As a result of RPW attack, the palm is destroyed and the tree collapses and dies.
A high density of RPW, developed in P. canariensis, is now present despite to the control measures, in Sicily. Palm trees represent in Mediterranean area an important part of cultural heritage in cities, botanical and historical gardens, which conserve many different palm species. In addition Mediterranean flora is also characterized by the presence of the native palm specie Chamerops humilis. In order to understand if the C. humilis is a suitable host of RPW, we investigate the natural infestation of RPW on this native palm. Moreover we analysed the morphological and molecular characters of RPW populations collected from C. humilis and P. canariensis. The study highlights the necessity to correlate the degree of genetic differences in the population of invasive species, as RPW, to predict the impact on natural flora and on other hosts
Insights about the ability of folate based supramolecular gels to act as targeted therapeutic agents
With the aim to obtain targeted chemotherapeutic agents, imidazolium and ammonium-based folate salts were synthesized. Their photophysical behavior was investigated both in buffer and buffer/DMSO solution as well as in solid phase, performing UV-vis and fluorescence investigations. Properties of the aggregates were also analyzed by dynamic light scattering. Gelation ability of the salts was analyzed in biocompatible solvents, and gel phases obtained were characterized by determining critical gelation concentrations and gel-solution transition temperatures. Insights about gelator interactions in the tridimensional network were also gained performing ATR-FTIR investigation. Properties of soft materials were further analyzed performing rheology measurements, scanning electron microscopy, fluorescence and resonance light scattering investigations. Antiproliferative activity of organic salts was tested towards two breast cancer cell lines, expressing different levels of folate receptor, namely MDA-MB-231 and MCF-7, and a normal epithelial cell line, like h-TER T-RPE-1, by using MTT assay. Dichlodihydrofluorescein acetate test was performed to verify the role of oxidative stress in cell death. Finally, antiproliferative activity was also evaluated in gel phase, to verify if salts were able to retain biological activity also after the entrapment in the gelatinous network. Results collected evidence that folate based organic salts were able to behave as targeted chemotherapeutic agents both in solution and gel phase, showing uptake mechanism and selectivity indexes that depend on both cancer cell line nature and salt structure
Safe use of opioids in chronic kidney disease and hemodialysis patients. ips and tricks for non pain specialist
Abstract: In patients suffering from moderate-to-severe chronic kidney disease (CKD) or end-stage renal disease (ESRD), subjected to hemodialysis (HD), pain is very common, but often underestimated. Opioids are still the mainstay of severe chronic pain management; however, their prescription in CKD and HD patients is still significantly low and pain is often under-treated. Altered pharmacokinetics and the lack of clinical trials on the use of opioids in patients with renal impairment increase physicians’ concerns in this specific population. This narrative review focused on the correct and safe use of opioids in patients with CKD and HD. Morphine and codeine are not recommended, because the accumulation of their metabolites may cause neurotoxic symptoms. Oxycodone and hydromorphone can be safely used, but adequate dosage adjustments are required in CKD. In dialyzed patients, these opioids should be considered as second-line agents and patients should be carefully mon- itored. According to different studies, buprenorphine and fentanyl could be considered first- line opioids in the management of pain in CKD; however, fentanyl is not appropriate in patients undergoing HD. Tapentadol does not need dosage adjustment in mild-to-moderate renal impairment conditions; however, no data are available on its use in ESRD. Opioid- related side effects may be exacerbated by common comorbidities in CKD patients. Opioid- induced constipation can be managed with peripherally-acting-μ-opioid-receptor-antagonists (PAMORA). Unlike the other PAMORA, naldemedine does not require any dose adjustment in CKD and HD patients. Accurate pain diagnosis, opioid titration and tailoring are manda- tory to minimize the risks and to improve the outcome of the analgesic therapy
BIOACTIVE MOLECULES FROM MARINE INVERTEBRATE ORGANISMS AS POTENTIAL TOOLS IN RESTORATION PROCEDURES
In the last decades molecular biology has provided innovative approaches in order to set up specific protocols for the conservation and restoration of cultural assets.
In this study, which falls within the so called field of Blue-biotechnology, new bio-reactive peptides isolated from marine invertebrate organisrns (Cnidaria and Molluscs) were tested aim to bio-cleaning (proteolytic- peptides) the surfaces or
to control (antimicrobial-peptides) the colonization of historic-artistic manufacts by fungi or bacteria. Particularly, the proteolytic-peptides showed hydrolytic activity, specific for animal-glue, in a range of temperatures of 4-37°C; than
acting without heating the surface, by a contro Iled procedure and avoiding damages to the constitutive materials, ali criteria required for conservation /restoration procedures. These hydrolases allow to carry out the removal of the protein layers in a controlled way, acting at the same temperature of the
environment where the objects are restored (19-25.5 0C). lnstead, the antirnicrobial-peptides have been tested on a plethora of fungi and bacteria
colonies and a specific activity, against Micrococcus spp., have been showed. We are testing the antimicrobial-peptides as a "biologica! biocide" in order to protect both organic and inorganic substrates.
We hypothesize that the use of these molecules will give an important contribution to the development of innovative and efficient technologies concerning bio-cleaning and antimicrobial growth protocols, according to conservative restoration procedures
Disentangling the initiation from the response in joint attention: an eye-tracking study in toddlers with autism spectrum disorders
Joint attention (JA), whose deficit is an early risk marker for autism spectrum disorder (ASD), has two dimensions: (1) responding to JA and (2) initiating JA. Eye-tracking technology has largely been used to investigate responding JA, but rarely to study initiating JA especially in young children with ASD. The aim of this study was to describe the differences in the visual patterns of toddlers with ASD and those with typical development (TD) during both responding JA and initiating JA tasks. Eye-tracking technology was used to monitor the gaze of 17 children with ASD and 15 age-matched children with TD during the presentation of short video sequences involving one responding JA and two initiating JA tasks (initiating JA-1 and initiating JA-2). Gaze accuracy, transitions and fixations were analyzed. No differences were found in the responding JA task between children with ASD and those with TD, whereas, in the initiating JA tasks, different patterns of fixation and transitions were shown between the groups. These results suggest that children with ASD and those with TD show different visual patterns when they are expected to initiate joint attention but not when they respond to joint attention. We hypothesized that differences in transitions and fixations are linked to ASD impairments in visual disengagement from face, in global scanning of the scene and in the ability to anticipate object's action
Using Brain Connectivity Measure of EEG Synchrostates for Discriminating Typical and Autism Spectrum Disorder
This is the author accepted manuscript. The final version is available from IEEE via the DOI in this record.In this paper we utilized the concept of stable phase synchronization topography - synchrostates - over the scalp derived from EEG recording for formulating brain connectivity network in Autism Spectrum Disorder (ASD) and typically-growing children. A synchronization index is adapted for forming the edges of the connectivity graph capturing the stability of each of the synchrostates. Such network is formed for 11 ASD and 12 control group children. Comparative analyses of these networks using graph theoretic measures show that children with autism have a different modularity of such networks from typical children. This result could pave the way to a new modality for possible identification of ASD from non-invasively recorded EEG data
NETME: on-the-fly knowledge network construction from biomedical literature
Background: The rapidly increasing biological literature is a key resource to automatically extract and gain knowledge concerning biological elements and their relations. Knowledge Networks are helpful tools in the context of biological knowledge discovery and modeling. Results: We introduce a novel system called NETME, which, starting from a set of full-texts obtained from PubMed, through an easy-to-use web interface, interactively extracts biological elements from ontological databases and then synthesizes a network inferring relations among such elements. The results clearly show that our tool is capable of inferring comprehensive and reliable biological networks
Effects of Probiotic Supplementation on Gastrointestinal, Sensory and Core Symptoms in Autism Spectrum Disorders: A Randomized Controlled Trial
The microbiota-gut-brain axis has been recently recognized as a key modulator of neuropsychiatric health. In this framework, probiotics (recently named “psychobiotics”) may modulate brain activity and function, possibly improving the behavioral profiles of children with Autism Spectrum Disorder (ASD). We evaluated the effects of probiotics on autism in a double-blind randomized, placebo-controlled trial of 85 preschoolers with ASD (mean age, 4.2 years; 84% boys). Participants were randomly assigned to probiotics (De Simone Formulation) (n=42) or placebo (n=43) for six months. Sixty-three (74%) children completed the trial. No differences between groups were detected on the primary outcome measure, the Total Autism Diagnostic Observation Schedule - Calibrated Severity Score (ADOS-CSS). An exploratory secondary analysis on subgroups of children with or without Gastrointestinal Symptoms (GI group, n= 30; NGI group, n=55) revealed in the NGI group treated with probiotics a significant decline in ADOS scores as compared to that in the placebo group, with a mean reduction of 0.81 in Total ADOS CSS and of 1.14 in Social-Affect ADOS CSS over six months. In the GI group treated with probiotics we found greater improvements in some GI symptoms, adaptive functioning, and sensory profiles than in the GI group treated with placebo. These results suggest potentially positive effects of probiotics on core autism symptoms in a subset of ASD children independent of the specific intermediation of the probiotic effect on GI symptoms. Further studies are warranted to replicate and extend these promising findings on a wider population with subsets of ASD patients which share targets of intervention on the microbiota-gut-brain axis. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT02708901
Multimodal functional and structural brain connectivity analysis in autism: A preliminary integrated approach with EEG, fMRI and DTI
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.This paper proposes a novel approach of integrating different neuroimaging techniques to characterize an autistic brain. Different techniques like EEG, fMRI and DTI have traditionally been used to find biomarkers for autism, but there have been very few attempts for a combined or multimodal approach of EEG, fMRI and DTI to understand the neurobiological basis of autism spectrum disorder (ASD). Here, we explore how the structural brain network correlate with the functional brain network, such that the information encompassed by these two could be uncovered only by using the latter. In this paper, source localization from EEG using independent component analysis (ICA) and dipole fitting has been applied first, followed by selecting those dipoles that are closest to the active regions identified with fMRI. This allows translating the high temporal resolution of EEG to estimate time varying connectivity at the spatial source level. Our analysis shows that the estimated functional connectivity between two active regions can be correlated with the physical properties of the structure obtained from DTI analysis. This constitutes a first step towards opening the possibility of using pervasive EEG to monitor the long-term impact of ASD treatment without the need for frequent expensive fMRI or DTI investigations
- …