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Biology subjects

Di Luca, M.

Publications and source records attributed to Di Luca, M..

10 recordsLinked to original sources

The MosAICo ecosystem: bridging the taxonomic gap in vector surveillance with real-time entomological artificial intelligence

Mosquito-borne diseases represent an escalating global health threat, driven by climate change, urbanization, and the spread of invasive vectors into new territories. Effective surveillance is constrained by a critical taxonomic impediment: the rate of specimen collection far outpaces the capacity of expert entomologists to process and identify trap catches. To address this bottleneck we developed MosAICo, an integrated AI-powered ecosystem for automated mosquito species identification designed for real-world, national-scale entomological surveillance. The system combines a standardized benchtop imaging device with MosAICo-Net, a deep learning pipeline enabling efficient and principled open-set recognition and uncertainty quantification. Trained and evaluated on 12, 499 specimens spanning 15 species collected across Italy, the model identifies seven priority vector species while explicitly rejecting out-of-distribution specimens. On a geographically stratified held-out test set, MosAICo-Net achieved over 90% accuracy on target species, and an AUROC of 0.96 for out-of-distribution detection. Field validation across 20 Italian surveillance sites confirmed these results: 94% micro accuracy on 1, 470 field-collected target specimens and strong agreement with expert manual counts ([Formula] = 0.66). To assess cross-geographic generalizability, the system was further evaluated on 118 Aedes albopictus specimens collected at the fringe of the species invasion front in Ghana: a 97.4% accuracy with only a single specimen escalated to expert review, suggests that MosAICo is well-suited for deployment in distant and epidemiologically critical regions. The system processes up to 82 specimens per image, matching expert throughput at constant speed regardless of taxonomic complexity. By embedding uncertainty-aware AI within a standardized hardware-software pipeline, MosAICo acts as a scalable force multiplier for public health entomology, freeing expert attention for rare, invasive, or ambiguous specimens that require human validation.

ecology↗

Lactate potentiates NMDA receptor currents via an intracellular redox mechanism targeting cysteines in the C-terminal domain of GluN2B subunits: implications for synaptic plasticity

SummaryThrough the Astrocyte Neuron Lactate Shuttle, astrocyte-derived lactate fuels the high-energy demands of neurons and acts as a signaling molecule, promoting synaptic plasticity and memory consolidation. Lactate regulates neuronal excitability and modulates the expression of genes related to synaptic plasticity and neuroprotection, but the molecular mode for these signaling actions is uncertain. Using patch-clamp recordings in cultured cortical neurons, we found that lactate enhances both the amplitude and the inactivation time constant of NMDA receptor currents (INMDAR) evoked by brief applications of glutamate and glycine. Not reproduced by HCAR1 agonists, this modulation depends on monocarboxylate transporters and lactate dehydrogenase, indicating the requirement for lactate entry and metabolic conversion into pyruvate and NADH formation within neurons. Disruption of intracellular calcium dynamics or inhibition of Ca2+/calmodulin-dependent protein kinase II (CaMKII), a NMDAR-associated kinase linking Ca2+ signal to long-term potentiation (LTP), significantly diminishes the effects of lactate on INMDAR. We identified two redox-sensitive cysteine- containing sequences in the intrinsically disordered intracellular C-terminal domain of the GluN2B subunit that play a role in the potentiation of NMDAR by lactate. In a compelling set of experiments using HEK cells, we observed that the presence of functional CaMKII and GluN2B-containing NMDARs is necessary for the lactate-enhancing effects. Mutations in GluN2B that prevent CaMKII binding or redox regulation via cysteines abrogate the modulatory action of lactate. Immunoprecipitation experiments in neurons attest that lactate increases the association between CaMKII and GluN2B. This interaction is crucial for the potentiation of INMDAR amplitude by lactate. Proximity ligation assays between GluN2B and the postsynaptic density marker PSD-95 revealed that lactate induced an accumulation of GluN2B in dendritic spines, an effect that was prevented by a CaMKII peptide inhibitor. These results highlight a mechanistic pathway whereby lactate boosts NMDAR function through intracellular metabolic conversion and redox-sensitive interactions requiring CaMKII, establishing a link between astrocyte metabolism and synaptic modulation in neurons.

neuroscience↗

N-Glycans on the extracellular domain of the Notch1 receptor control Jagged-1 induced Notch signalling and myogenic differentiation of S100β resident vascular stem cells

Notch signalling, critical for development and postnatal homeostasis of the vascular system, is highly regulated by several mechanisms including glycosylation. While the importance of O-linked glycosylation is widely accepted, the structure and function of N-glycans has yet to be defined. Here, we take advantage of lectin binding assays in combination with pharmacological, molecular, and site-directed mutagenetic approaches to study N-glycosylation of the Notch1 receptor. We find that several key oligosaccharides containing bisecting or core fucosylated structures decorate the receptor, control expression and receptor trafficking, and dictate Jagged-1 activation of Notch target genes and myogenic differentiation of multipotent S100{beta} vascular stem cells. N-glycans at asparagine (N) 1241 and 1587 protect the receptor from accelerated degradation, while the oligosaccharide at N888 directly affects signal transduction. Conversely, N-linked glycans at N959, N1179, N1489 do not impact canonical signalling but inhibit differentiation. Our work highlights a novel functional role for N-glycans in controlling Notch1 signalling and differentiation of vascular stem cells. TeaserA sweet development in Notch regulation of vascular smooth muscle cell differentiation

cell biology↗

A Methodological Framework to Assess the Accuracy of Virtual Reality Hand-Tracking Systems: A case study with the Oculus Quest 2

Optical marker-less hand-tracking systems incorporated into virtual reality (VR) headsets are transforming the ability to assess motor skills, including hand movements, in VR. This promises to have far-reaching implications for the increased applicability of VR across scientific, industrial and clinical settings. However, so far, there is little data regarding the accuracy, delay and overall performance of these types of hand-tracking systems. Here we present a novel methodological framework which can be easily applied to measure these systems absolute positional error, temporal delay and finger joint-angle accuracy. We used this framework to evaluate the Meta Quest 2 hand-tracking system. Our results showed an average fingertip positional error of 1.1cm, an average finger joint angle error of 9.6o and an average temporal delay of 38.0ms. Finally, a novel approach was developed to correct for these positional errors based on a lens distortion model. This methodological framework provides a powerful tool to ensure the reliability and validity of data originating from VR-based, marker-less hand-tracking systems.

neuroscience↗

Native Extracellular Matrix Orientation Determines Multipotent Vascular Stem Cell Proliferation in Response to Cyclic Uniaxial Tensile Strain and Simulated Stent Indentation

Cardiovascular disease is the leading cause of death worldwide, with multipotent vascular stem cells (MVSC) implicated in contributing to diseased vessels. MVSC are mechanosensitive cells which align perpendicular to cyclic uniaxial tensile strain. Within the blood vessel wall, collagen fibers constrain cells so that they are forced to align circumferentially, in the primary direction of tensile strain. In these experiments, MVSC were seeded onto the medial layer of decellularized porcine carotid arteries, then exposed to 10%, 1 Hz cyclic tensile strain for 10 days with the collagen fiber direction either parallel or perpendicular to the direction of strain. Cells aligned with the direction of the collagen fibers regardless of the orientation to strain. Cells aligned with the direction of strain showed an increased number of proliferative Ki67 positive cells, while those strained perpendicular to the direction of cell alignment showed no change in cell proliferation. A bioreactor system was designed to simulate the indentation of a single, wire stent strut. After 10 days of cyclic loading to 10% strain, MVSC showed regions of densely packed, highly proliferative cells. Therefore, MVSC may play a significant role in in-stent restenosis, and this proliferative response could potentially be controlled by controlling MVSC orientation relative to applied strain.

bioengineering↗

Mosquitoes of the Maculipennis complex in Northern Italy

The correct identification of mosquito vectors is often hampered by the presence of morphologically indiscernible sibling species. The Maculipennis complex is one of these groups which include both malaria vectors of primary importance and species of low/negligible epidemiological relevance, of which distribution data in Italy are outdated. Our study was aimed at providing an updated distribution of Maculipennis complex in Northern Italy through the sampling and morphological/molecular identification of specimens from five regions. The most abundant species was Anopheles messeae s.l. (2032), followed by Anopheles maculipennis s.s. (418), Anopheles atroparvus (28) and Anopheles melanoon (13). The distribution of species was characterized by Ecological Niche Models (ENMs), fed by recorded points of presence. ENMs provided clues on the ecological preferences of the detected species, with An. messeae s.l. linked to stable breeding sites and An. maculipennis s.s. more associated to ephemeral breeding sites. We demonstrate that historical Anopheles malaria vectors are still widespread in Northern Italy.

ecology↗

The calcium binding protein S100β marks Hedgehog-responsive perivascular stem cells that contribute to intimal thickening following iatrogenic flow restriction

A hallmark of subclinical atherosclerosis is the accumulation of vascular smooth muscle cell (SMC)-like cells leading to intimal thickening. While medial SMCs contribute, the participation of hedgehog responsive resident vascular stem cells (vSCs) to lesion formation remains unclear. Using transgenic eGFP mice and genetic lineage tracing of S100{beta} vSCs in vivo, we identified S100{beta}/Sca1 cells derived from a S100{beta} non-SMC parent population within lesions that co-localise with smooth muscle -actin (SMA) cells following iatrogenic flow restriction, an effect attenuated following hedgehog inhibition with the smoothened inhibitor, cyclopamine. In vitro, S100{beta}/Sca1 cells isolated from atheroprone regions of the mouse aorta expressed hedgehog signalling components, acquired the di-methylation of histone 3 lysine 4 (H3K4me2) stable SMC epigenetic mark at the Myh11 locus and underwent myogenic differentiation in response to recombinant sonic hedgehog (SHh). Both S100{beta} and PTCH1 cells were present in human vessels while S100{beta} cells were enriched in arteriosclerotic lesions. Recombinant SHh promoted myogenic differentiation of human induced pluripotent stem cell-derived S100{beta} neuroectoderm progenitors In vitro. We conclude that hedgehog responsive S100{beta} vSCs contribute to lesion formation and support targeting hedgehog signalling to treat subclinical arteriosclerosis.

cell biology↗

CAP2 is a novel regulator of Cofilin in synaptic plasticity and Alzheimer’s disease

Cofilin is one of the major regulators of actin dynamics in spines where it is required for structural synaptic plasticity. However, our knowledge of the mechanisms controlling Cofilin activity in spines remains still fragmented. Here, we describe the cyclase-associated protein 2 (CAP2) as a novel master regulator of Cofilin localization in spines. The formation of CAP2 dimers through its Cys32 is important for CAP2 binding to Cofilin and for normal spine actin turnover. The Cys32-dependent CAP2 homodimerization and association to Cofilin are triggered by long-term potentiation (LTP) and are required for LTP-induced Cofilin translocation into spines, spine remodeling and the potentiation of synaptic transmission. This mechanism is specifically affected in the hippocampus, but not in the superior frontal gyrus, of both Alzheimers Disease (AD) patients and APP/PS1 mice, where CAP2 is down-regulated and CAP2 dimer synaptic levels are reduced. In AD hippocampi, Cofilin preferentially associates with CAP2 monomer and is aberrantly localized in spines. Taken together, these results provide novel insights into structural plasticity mechanisms that are defective in AD.

neuroscience↗

Chemical biofilm dislodgement with chelating and reducing agents in comparison to sonication: implications for the diagnosis of implant associated infection

Sonication of removed devices improved the microbiological diagnosis of infection. Recently, chemical agents have been investigated for dislodgement of biofilms, including the chelating agent ethylenediaminetetraacetic acid (EDTA) and the reducing agent dithiothreitol (DTT). We compared the efficacy of chemical methods (EDTA and DTT) to sonication for biofilm dislodgement. Staphylococcus epidermidis (ATCC 35984) and Pseudomonas aeruginosa (ATCC 53278) biofilms were grown on porous glass beads for 3 days. After biofilm formation, beads were exposed to 0.9% saline, sonication and/or chemical agents. Quantitative and qualitative biofilm analyses were performed by colony counting (CFU/ml), isothermal microcalorimetry and scanning electron microscopy. The colony counts after treatment with EDTA and DTT were similar to those after exposure to 0.9% saline (6.3, 6.1 and 6.0 log CFU/ml, respectively) for S. epidermidis biofilms, and (5.1, 5.2 and 5.0 log CFU/ml, respectively) for P. aeruginosa biofilm. Sonication detected higher CFU counts (7.5 log CFU/ml) for S. epidermidis; (p<0.05) and 6.5 log for P. aeruginosa biofilm (p <0.05). Concordant results were detected with isothermal microcalorimetry and scanning electron microscopy. In conclusion, the CFU count after treatment of S. epidermidis or P. aeruginosa biofilms with EDTA and DTT was similar to those observed after 0.9% saline used as control. In contrast, sonication was superior to chemical methods for biofilm dislodgment and detection of microorganisms in sonication fluid. In conclusion, our study showed that sonication is superior to chemical method to dislodge bacterial biofilm from artificial surface and should be considered as standard diagnostic method for biofilm detection in implant-associated infections.

microbiology↗

Evaluation of Sb-1 bacteriophage activity in enhancing antibiotic efficacy against biofilm, degrading the exopolysaccharide matrix and targeting persister cells of Staphylococcus aureus

Most research on phage therapy focused on planktonic bacteria, whereas bacteriophage activity against biofilms is limited. We evaluated the capability of Staphylococcus aureus-specific bacteriophage Sb-1 to eradicate biofilm alone and in combination with different classes of antibiotics, to degrade the extracellular matrix and target persister cells. Biofilm of methicillin-resistant S. aureus (MRSA) ATCC 43300 was treated with Sb-1 alone or in (simultaneous or staggered) combination with either fosfomycin, rifampin, vancomycin, daptomycin or ciprofloxacin. The matrix was visualized by confocal fluorescent microscopy. Persister cells were treated with 104 and 107 PFU/mL Sb-1 for 3 hours in PBS, followed by CFU counting. Alternatively, bacteria were washed and incubated in fresh BHI medium and the bacterial growth assessed after further 24-hours. Pre-treatment with Sb-1 followed by the administration of sub-inhibitory concentrations of antibiotic exerted a considerable synergistic effect in eradicating MRSA biofilm. Sb-1 determined a dose-dependent reduction of matrix exopolysaccharide. 107 PFU/mL Sb-1 showed direct killing activity on persisters. However, even a lower titer had lytic activity when phage-treated persister cells were inoculated in fresh medium, reverting to a normal-growing phenotype. This study provides valuable data regarding the capability of Sb-1 to enhance antibiotic efficacy, exhibiting specific antibiofilm features. Its ability to degrade the MRSA polysaccharide matrix and target persister cells makes Sb-1 suitable for the therapy of biofilm-associated infections.

microbiology↗