Search Results (1,275)

Protein S-palmitoylation is a reversible lipid modification that regulates various aspects of protein function, including membrane association, subcellular localization, trafficking, stability, and activity. The depalmitoylase ABHD17A removes palmitate from multiple substrates, but its cellular positioning and the role of its own palmitoylation in regulating its function remain unclear. This study identifies a palmitoylation code within the conserved N-terminal cysteine cluster of ABHD17A, which governs its intracellular distribution and plasma membrane (PM) targeting. N-terminal palmitoylation is essential for PM localization. Through the use of code-restricted mutants, we found that modifications in the middle region (C14, C15) are critical for PM targeting and catalytic activity, while modifications at the front (C10, C11) and rear (C18) influence endosomal routing and delivery to the PM. Alanine scanning revealed that adjacent hydrophobic residues, particularly L9 and F13, are crucial for initial engagement with endomembranes. Sequence analysis and mutagenesis identified two tyrosine-based YXXØ motifs within the alpha/beta hydrolase fold; disruption of the proximal motif (L115A) decreased surface abundance and redirected ABHD17A to autophagosomes, indicating a need for YXXØ-dependent endosomal sorting, likely at the trans-Golgi network. Biochemical assays demonstrated a continuum of acylation states influenced by the palmitoylation code. This requirement for the middle region was conserved in ABHD17B and ABHD17C. Overall, our findings suggest a stepwise mechanism for ABHD17A delivery to the PM, enabling its depalmitoylase activity on membrane-bound substrates. Full article

This study examines the potential in vitro application of different concentrations of titanium dioxide (TiO₂) nanoparticles (NPs) irradiated with UV light for the sanitation of recirculating aquaculture systems (RASs) and their antiviral activity. The diverse effects of Nodavirus on immune gene expression (i.e., pro-inflammatory and anti-inflammatory genes, cellular response genes, humoral response genes, and stress genes) were studied using RT-qPCR (Reverse Transcription Quantitative Polymerase Chain Reaction). In addition, the viability and cytopathic effect in E-11 fish cells were also investigated. The results obtained did not show a clear cytopathic effect under the reversed-phase microscope observation at different TiO₂ concentrations. A significant decrease in viral coat protein gene expression was observed when using 2.5 and 1.25 g/L TiO₂ suspensions under UV irradiation. TiO₂ at 1.25 g/L induced an inflammatory response to Nodavirus by increasing the expression of all target genes. Thus, this work suggests that TiO₂ NPs can strengthen the immune system of fish to fight virus infection and make aquaculture a greener and more sustainable activity. Full article

Oculocutaneous albinism (OCA) increases susceptibility to ultraviolet (UV) skin damage, skin cancer risk, and psychosocial burden. Data from Madagascar are lacking. We conducted a six-month pilot study (July–December 2024) in northern Madagascar (DIANA and SAVA regions). Forty-one individuals with OCA were enrolled. Baseline socio-demographic, clinical, and behavioral data were collected through interviews and dermatological examinations. A structured program provided education, culturally adapted materials, and photoprotective resources, with monthly follow-up visits. The cohort included 22 males and 19 females, with a mean age of 18 years (range: 1 month–35 years). Actinic keratoses were present in 61% of participants, and invasive skin cancer in 4.9%. All patients had photophobia and nystagmus. Social discrimination was reported by 65.9%, with 12.2% describing severe abuse. Baseline photoprotection was inadequate: 43.9% reported no protective practices, 7.3% used sunscreen, and 19.5% avoided midday sun. Follow-up was completed by 20/41 patients (48.8%). Among completers, paired analysis showed a decrease in sunburn prevalence from 95.0% to 10.0% (p < 0.0001), an increase in regular sunscreen use from 0.0% to 100.0% (p < 0.0001), use of protective clothing from 35.0% to 80.0% (p = 0.0039), and adoption of behavioral strategies from 15.0% to 50.0% (p = 0.0156). This first study on OCA in northern Madagascar demonstrates a high burden of UV-related dermatoses and stigma. A low-cost community intervention significantly improved photoprotection. Wider implementation could reduce morbidity and enhance quality of life in resource-limited settings. Full article

This work presents the HX-responsiveness of the following heteroleptic donor–M–acceptor dithiolene complexes: Bu4N[MII(L1)(L2)] [M = Ni(1), Pd(2), Pt(3)], where L1 is the chiral acceptor ligand [(R)-α-MBAdto = chiral (R)-(+)α-methylbenzyldithio-oxamidate] and L2 is the donor ligand (tdas = 1,2,5-thiadiazole-3,4-dithiolato). Addition of hydrohalic acids induces a strong bathochromic shift and visible color change, which is fully reversed by ammonia (NH₃). Moreover, the sensing capability of 1 was further evaluated by deposition on a cellulose substrate. Exposure to HCl vapors induces an evident color change from purple to green, whereas successive exposure to NH₃ vapors fully restores the purple color. Remarkably, cellulose films of 1 were revealed to be excellent optical sensors against the response to triethylamine, which is a toxic volatile amine. Moreover, the HCl-responsiveness of the nonlinear optical properties of complexes 1, 2, and 3 embedded into a poly(methyl methacrylate) poled matrix was demonstrated. Reversible chemical second harmonic generation (SHG) switching is achieved by exposing the poled films to HCl vapors and then to NH₃ vapors. The SHG response ratio HCl–adduct/complex is significant (around 1.5). Remarkably, the coefficients of the susceptibility tensor for the HCl–adduct films are always larger than those of the respective free-complex films. Density Functional Theory (DFT) and time-dependent DFT calculations help in highlighting the structure–properties relationship. Full article

A polyamidoamine-based hydrogel (H-M-GLY) and its montmorillonite-based composite (H-M-GLY/MMT) were studied as selective cleaning materials for cultural heritage conservation. H-M-GLY was synthesized from a glycine-based polyamidoamine oligomer with acrylamide terminals (M-GLY) through radical polymerization at pH 7.3 and had a basic character. The M-GLY oligomer was in turn synthesized from N,N′-methylenebisacrylamide and glycine in a 1:0.85 molar ratio. H-M-GLY/MMT was obtained by cross-linking a 1:0.1—weight ratio—M-GLY/MMT mixture at pH 4.0, to promote polyamidoamine-MMT interaction. The composite hydrogel absorbed less water than the plain hydrogel and proved tougher, due to montmorillonite’s electrostatic interactions with the positively charged M-GLY units. Scanning electron microscopic analysis showed that MMT was uniformly dispersed throughout the hydrogel. Both hydrogels were subjected to ink bleeding tests on papers written with either iron gall or India ink. Microscopic observation revealed neither bleeding nor release of hydrogel fragments. Being basic, H-M-GLY successfully deacidified the surface of aged paper. H-M-GLY/MMT, swollen in a 1:9 ethanol/water solution, was found to be effective in removing wax, known to trap carbonaceous particles and form dark stains on artistic artifacts. This study demonstrates the great potential of polyamidoamine-based hydrogels as versatile selective cleaning systems for cellulosic and other cultural heritage materials. Full article

Santolina chamaecyparissus L. (Asteraceae), cultivated at the Ghirardi Botanic Garden (Toscolano Maderno, Brescia, Northern Italy) of the University of Milan, was investigated adopting a multidisciplinary research approach: micromorphological and histochemical, with special attention on the secretory structures producing secondary metabolites; phytochemical, with the analysis of the essential oil (EO) composition from the air-dried, flowered aerial parts gathered once per year across two consecutive years (2021 and 2022); bio-ecological, focusing, based on literature data, on the biological activity and ecology of the main EO compounds; didactic–educational, with the ex novo realization of an interpretative apparatus at the study site. Two distinct types of secretory structures were described: biseriate glandular trichomes and secretory ducts, both producing an oleoresin rich in flavonoids. Phytochemical analysis revealed stable EO profiles across the two years with regards to the total number of compounds (39 vs. 40), the main chemical classes (oxygenated monoterpenes (72.67% vs. 78.61%) and monoterpenes hydrocarbons (15.06% vs. 10.48%) and the key single components (artemisia ketone, 52.74% vs. 55.67%; camphor, 13.00% vs. 16.18%). The literature data on the bio-ecology of the main compounds allowed us to confirm antimicrobial, antioxidant, and anti-inflammatory properties. Concerning the dissemination actions, the outcomes of this multidisciplinary work were integrated into a new interpretive apparatus for S. chamaecyparissus at the Ghirardi Botanic Garden. The research results enhance our understanding of this species, supporting its potential EO application in medicine and agriculture. Full article

Copper and iron species were co-deposited onto a hydroxyapatite surface to produce bimetallic catalysts. Characterization techniques (XRD, XPS, DR-UV spectroscopy and TEM-EDX) helped in unveiling the speciation, nuclearity, and electronic properties of copper and iron in samples with variable total metal loading (1–10 wt.%) and relative Cu-to-Fe ratios. The speciation of Cu was revealed to be not affected by Fe and vice versa. Conversely, the metal loading turned out to be a key factor ruling the aggregation state of Cu and Fe species. The samples were tested as catalysts in the Selective Catalytic Reduction of NO by NH₃ (NH₃-SCR) in dry and wet environments under quasi-real conditions (50,000 ppm O₂; 50,000 ppm H₂O, if present; 120,000 h⁻¹ GHSV) in the 200−500 °C interval. Although the combination of Cu and Fe affords a modest improvement in water resistance compared to their monometallic counterparts, no substantial enhancement in activity was observed for the bimetallic hydroxyapatite-based SCR catalysts. Full article

Exposure to hypoxia at high altitudes is significantly associated with impairments in learning and memory functions, as well as abnormalities in neuronal function and synaptic plasticity. Recent research has indicated that mitochondrial reactive oxygen species (mtROS) play a role in regulating microglial activation and mediating neurotoxic damage in the hippocampal CA1 region. Nicotinamide riboside (NR), upon absorption, is rapidly converted into nicotinamide adenine dinucleotide (NAD+), which is involved in the production of mitochondrial adenosine triphosphate (ATP). The potential of NR to protect dendritic spine plasticity in hippocampal CA1 neurons following hypoxia exposure, potentially through the inhibition of microglial activation, warrants further investigation. To this end, a mouse model simulating hypoxia at an altitude of 6000 m over a two-week period, along with a BV2 cells and conditional co-culture of BV2 cells and HT22 cells 1%O₂ hypoxia model, was developed. Behavioral assessments indicated that, relative to the normoxia group, mice subjected to hypoxia exhibited a significant reduction in the time spent in the target quadrant, the distance traveled within the target quadrant, the number of platform crossings, and the novel object recognition index. Furthermore, Golgi staining revealed a marked decrease in the density of dendritic spines in the hippocampal CA1 region in the hypoxia-exposed mice compared to the normoxia group. Subsequently, A daily dosage of 400 mg/kg of NR was administered for two weeks and 0.5 mM NR was used in a conditional co-culture model. Results demonstrated that, in comparison to the hypoxia group, the group receiving combined hypoxia and NR treatment showed significant improvements in the time spent in the target quadrant, the distance traveled within the target quadrant, the number of platform crossings, the novel object recognition index, and the density of dendritic spines in the hippocampal CA1 region. Additionally, transmission electron microscopy indicated a significant increase in the synaptic density of hippocampal neurons in the combined hypoxia exposure and NR treatment group compared to the hypoxia exposure group. Simultaneously, when compared to the hypoxia group, the combination of hypoxia and NR treatment resulted in an increased concentration of mitochondrial ATP. This treatment also partially restored mitochondrial membrane integrity, reduced mtROS levels, decreased the percent of Iba1⁺CD68⁺Iba1⁺ microglia, and lowered the interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNFα), and inducible nitric oxide synthase (iNOS) mRNA levels. These findings indicate that NR treatment may mitigate neurotoxic damage in the hippocampal CA1 region induced by hypoxia exposure, primarily through the attenuation of microglial activation and the reduction in mtROS production. Full article

Bacteroides fragilis, a prominent commensal of the human gut microbiota, plays a vital role in immune system regulation through its capsular polysaccharide A (PSA), which requires a glycolipid anchor structurally reminiscent of lipid A. While canonical Escherichia coli lipid A acts as a potent TLR4 agonist contributing to septic shock and inflammatory disorders, certain B. fragilis-derived glycolipids demonstrate antagonistic effects, offering potential as anti-inflammatory agents. In this study, we report the synthesis and preliminary computational evaluation of a library of glycolipids inspired by B. fragilis lipid A. Three lipid As, including a tetra-acylated 1-phosphoryl lipid A analog (Tetra C-1), were synthesized and assessed using molecular docking simulations targeting the human TLR4/MD-2 complex. Docking results reveal that Tetra C-1 exhibits more favorable antagonist binding characteristics compared to the well-studied TLR4 antagonist Eritoran. This work highlights a microbiota-informed strategy for the development of novel TLR4 antagonists, potentially enabling targeted modulation of innate immunity for therapeutic applications in inflammatory diseases and as vaccine adjuvants. Full article

Despite significant advances in understanding the genetics of Parkinson’s disease (PD) and Parkinsonism, the diagnostic yield remains low. Pathogenic variants of GBA1, which encodes the lysosomal enzyme β-glucocerebrosidase and causes recessive Gaucher dis-ease, are recognized as the most important genetic risk factor for PD in heterozygous carriers. This study focuses on the functional genomics of rare genetic variations in other lysosomal hydrolytic enzymes genes in patient-derived fibroblasts. We examined 49 early-onset PD patients using whole exome sequencing and in silico panel analysis based on a curated PD gene list. Two patients were found to carry the p.Asp313Tyr variant in the X-linked GLA gene (encoding GALA, typically associated with Fabry disease), and one patient carried the p.Arg419Gln variant in GLB1 (encoding β-Gal, linked to the recessive GM1 gangliosidosis and mucopolysaccharidosis type IVB). The in silico study of both variants supports a potentially damaging impact on the encoded protein function and structural destabilization. Additional candidate variants were found related to lysosomes, Golgi apparatus and neurodegeneration, suggesting a multifactorial contribution to the disease. However, none of these variants met diagnostic standards. Functional assays showed a significant decrease in GALA expression and partial retention of the enzyme in the trans-Golgi network in fibroblasts with GLA:p.Asp313Tyr, while altered Golgi morphology was observed in fibroblasts with GLB1:p.Arg419Gln. Moreover, all patients exhibited abnormalities in lysosomal morphology, altered lysosomal pH, and impaired autophagic flux. Our findings suggest that rare, heterozygous variants in lysosomal-related genes, even when individually insufficient for monogenic disease, can converge to impair lysosomal homeostasis and autophagic flux in EOPD. The underlying genetic and cellular heterogeneity among patients emphasizes the importance of combining genetic and functional approaches to better understand the mechanisms behind the EOPD, which could enhance both diagnosis and future treatments. Full article

DROSHA protein is widely known for its essential role in the microRNA (miRNA/miR) biogenesis pathway where, together with its co-factor DGCR8, it forms the “Microprocessor” complex and catalyzes the primary miRNA (pri-miRNA) processing in the nucleus. Nevertheless, DROSHA also seems to participate in several miRNA-independent cellular mechanisms, such as transcriptional regulation, RNA processing and genome integrity maintenance. Hence, the present study aims to further investigate novel miRNA-independent activities of DROSHA protein, with potentially regulatory roles in the oncogenesis of human cancer cells. Our results reveal a new, strong profile of microprocessor-independent DROSHA localization at the Golgi apparatus in several human cancer cell lines of different tissue origin, with hepatic carcinoma, thyroid cancer, urothelial bladder cancer, colon carcinoma and melanoma being the cellular model systems herein examined. Notably, oncogenic activity, malignancy grade and metastatic capacity are shown to be strongly associated with DROSHA’s compartmentalization at Golgi, a phenotype that does not seem to rely on p53 protein’s functionality. Taken together, through employment of advanced confocal laser scanning microscopy (CLSM) and molecular modeling, we herein unveil the ability of DROSHA, but not AGO2 and DICER, to reside at Golgi, where DROSHA can physically interact with the GM130 Golgi-specific component, thus indicating DROSHA’s engagement in non-canonical and miRNA-independent—but also Golgi apparatus-dependent—novel mechanisms that can be tightly coupled with malignancy dynamics and beneficially utilized as potential biomarkers and therapeutic targets for human cancer. Full article

The findings of non-invasive, multi-analytical research on two wall paintings located in the Santuario della Beata Vergine dei Miracoli in Saronno (Varese, Italy)—The Marriage of the Virgin and The Adoration of the Christ Child—are presented in this paper. The authorship of the latter is up for controversy, while the former is unquestionably attributed to Bernardino Luini. The objective was to assess the compatibility of their color palettes through material comparison. A complementary suite of non-invasive techniques, including X-ray fluorescence (XRF), external reflection FTIR, Raman, visible reflectance spectroscopy and hyperspectral imaging, were employed to characterize pigments and surface materials without sampling. Results confirm the use of historically consistent pigments such as calcium carbonate, ochres, Naples yellow, smalt, azurite and lapis lazuli. Differences in the application of blue pigments—lapis lazuli in The Marriage of the Virgin and azurite in The Adoration of the Christ Child—may reflect workshop variation rather than separate authorship. Spectral imaging revealed pigment mixing and layering strategies, especially in skin tones and shadow modeling. This study underscores the significance of diagnostics as an interpretive instrument, capable of contextualizing Luini’s paintings within the context of Renaissance creative practice, providing a framework relevant to analogous inquiries. Full article

Heparan sulfate proteoglycans serve as initial attachment sites for several viruses and bacteria. Recent studies suggest that SARS-CoV-2 similarly exploits these glycosaminoglycans, facilitating conformational changes in the spike protein that promote the interaction between the receptor-binding domain (S1-RBD) and the cellular angiotensin-converting enzyme 2 receptor (ACE2), thereby triggering the virus internalization process. The molecular details that drive this process, particularly the co-receptor role of heparan sulfate (HS), remain incompletely understood. The interaction between an HS hexasaccharide (hexa) and the N343 glycosylated S1-RBD of the wild-type (WT) and Omicron variant of SARS-CoV-2 was investigated. The conformational properties of hexa with these S1-RBDs in unbound and bound states are explored using multiple independent MD simulations; the protein binding epitope of hexa, as well as the details of its interaction with S1-RBD of the Omicron variant, are characterized by comparing experimental and theoretical ¹H STD NMR signals. This investigation identifies the role played by the glycosyl moiety at N343 in potentially affecting this interaction in both WT and Omicron S1-RBD, explaining the observed low specificity and multi-modal nature of the interaction between HS oligosaccharides and these S1-RBDs. Full article

Plant-insect mutualisms often drive the evolution of adaptive morphological and physiological traits, enabling ecological specialization and diversification. Fig trees (Ficus spp., Moraceae) and their pollinating wasps (Agaonidae) are engaged in a brood-site pollination mutualism that exemplifies such adaptive specializations. This study investigates the morphological and ecological roles of maculae, characterized as distinct-pigmented regions on the fig surface, in the mutualistic interaction between Ficus citrifolia and fig wasps. Through morphological analyses using light and electron microscopy, we demonstrated that maculae concentrate numerous stomata and exhibit secretory activity. This activity is evidenced by the exudation of a sugary-like solution and by the presence of epidermal and subepidermal cells with features consistent with sugar- and terpene-secreting cells, such as abundant starch reserves, numerous mitochondria, plastids containing osmiophilic droplets, a Golgi complex with dilated cisternae, oil bodies, and extensive endoplasmic reticulum. Histochemical tests confirmed a terpenic-sugary secretion in the macula cells. We demonstrated that non-pollinating fig wasps avoid ovipositing through macular regions. This behavior may reflect a selective pressure to prevent structural damage to maculae caused by ovipositor insertion, thus preserving their functional integrity. Temperature measurements revealed that figs are up to 10% cooler on average than the ambient air. Therefore, our findings suggest that fig maculae are multifunctional structures, simultaneously performing the roles of extrafloral nectaries, gas exchange, and thermal regulation, which are crucial for maintaining suitable internal conditions for wasp larval development. These results provide novel insights into previously underexplored plant adaptations supporting specialized brood-site pollination mutualisms. Full article

Retrograde cricopharyngeus dysfunction (R-CPD) is a recently recognized condition characterized by the inability to burp, typically accompanied by gurgling noises, bloating, and flatulence. Percutaneous botulinum neurotoxin (BoNT) injection into the cricopharyngeus muscle is a minimally invasive treatment with promising effects, although current evidence remains limited. In this prospective, open-label study, we evaluated the clinical effects of increasing doses (10 to 30 U) of EMG-guided unilateral BoNT injection in 67 patients with R-CPD. Symptom severity and quality of life were assessed at baseline and at 1 and 4 months post-treatment. The electromyographic (EMG) parameters of the cricopharyngeus were recorded to explore their association with symptom burden and treatment response. At a 1-month follow-up, 55.2% of patients were classified as responders (satisfaction score ≥ 6/10), with a higher rate (64.4%) observed at higher doses, particularly in female patients. Both symptom severity and quality of life improved significantly at 1 month and were sustained at 4 months. Higher cricopharyngeus EMG activity was associated with more severe symptoms and lesser treatment responses. Unilateral EMG-guided BoNT injection is a safe and effective treatment for R-CPD. Further studies should explore the potential role of electromyography in clarifying the pathophysiological aspects of R-CPD and guiding treatment. Full article