17 research outputs found
Crystallization Kinetics of Alkali Feldspar in Peralkaline Rhyolitic Melts: Implications for Pantelleria Volcano
Peralkaline rhyolites, associated with extensional tectonic settings, are medium to low viscosity magmas that often produce eruptive styles ranging from effusive to highly explosive eruptions. The role of pre-eruptive conditions and crystallization kinetics in influencing the eruptive style of peralkaline rhyolitic magmas has been investigated and debated considering equilibrium conditions. However, experimental constraints on the effect of disequilibrium in crystallization in such magmas are currently lacking in the literature. Therefore, we performed isobaric cooling experiments to investigate alkali feldspar crystallization kinetics in peralkaline rhyolitic melts. Experiments were performed under water-saturated, water-undersaturated, and anhydrous conditions between 25 and 100 MPa, at 670–790°C and with experimental durations ranging from 0.5 to 420 h. Here we present the first data on crystallization kinetics of alkali feldspar, which is the main crystal phase in peralkaline rhyolitic melts, in order to improve our understanding of the evolutionary timescales of these melts and their ability to shift between effusive and explosive activity. Our experimental results indicate that the alkali feldspar nucleation delay can range from hours to several days as a function of undercooling and H2O content in the melt. Thus, a peralkaline rhyolitic magma can be stored at the pre-eruptive conditions for days without important variations of its crystal fraction. This suggests that crystallization may not necessarily play the main role in triggering fragmentation during explosive eruptions of peralkaline rhyolitic magmas
Creatine kinase and progression rate in amyotrophic lateral sclerosis
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with no recognized clinical prognostic factor. Creatinine kinase (CK) increase in these patients is already described with conflicting results on prognosis and survival. In 126 ALS patients who were fast or slow disease progressors, CK levels were assayed for 16 months every 4 months in an observational case-control cohort study with prospective data collection conducted in Italy. CK was also measured at baseline in 88 CIDP patients with secondary axonal damage and in two mouse strains (129SvHSD and C57-BL) carrying the same SOD1G93A transgene expression but showing a fast (129Sv-SOD1G93A) and slow (C57-SOD1G93A) ALS progression rate. Higher CK was found in ALS slow progressors compared to fast progressors in T1, T2, T3, and T4, with a correlation with Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) scores. Higher CK was found in spinal compared to bulbar-onset patients. Transgenic and non-transgenic C57BL mice showed higher CK levels compared to 129SvHSD strain. At baseline mean CK was higher in ALS compared to CIDP. CK can predict the disease progression, with slow progressors associated with higher levels and fast progressors to lower levels, in both ALS patients and mice. CK is higher in ALS patients compared to patients with CIDP with secondary axonal damage; the higher levels of CK in slow progressors patients, but also in C57BL transgenic and non-transgenic mice designs CK as a predisposing factor for disease rate progression
Actions of the antihistaminergic clemastine on presymptomatic SOD1-G93A mice ameliorate ALS disease progression
Histamine Regulates the Inflammatory Profile of SOD1-G93A Microglia and the Histaminergic System Is Dysregulated in Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis (ALS) is a late-onset motor neuron disease where activated glia release pro-inflammatory cytokines that trigger a vicious cycle of neurodegeneration in the absence of resolution of inflammation. Given the well-established role of histamine as a neuron-to-glia alarm signal implicated in brain disorders, the aim of this study was to investigate the expression and regulation of the histaminergic pathway in microglial activation in ALS mouse model and in humans. By examining the contribution of the histaminergic system to ALS, we found that particularly via H1 and H4 receptors, histamine promoted an anti-inflammatory profile in microglia from SOD1-G93A mice by modulating their activation state. A decrease in NF-κB and NADPH oxidase 2 with an increase in arginase 1 and P2Y12 receptor was induced by histamine only in the ALS inflammatory environment, but not in the healthy microglia, together with an increase in IL-6, IL-10, CD163, and CD206 phenotypic markers in SOD1-G93A cells. Moreover, histaminergic H1, H2, H3, and H4 receptors, and histamine metabolizing enzymes histidine decarboxylase, histamine N-methyltransferase, and diamine oxidase were found deregulated in spinal cord, cortex, and hypothalamus of SOD1-G93A mice during disease progression. Finally, by performing a meta-analysis study, we found a modulated expression of histamine-related genes in cortex and spinal cord from sporadic ALS patients. Our findings disclose that histamine acts as anti-inflammatory agent in ALS microglia and suggest a dysregulation of the histaminergic signaling in ALS
Intramuscular IL-10 Administration Enhances the Activity of Myogenic Precursor Cells and Improves Motor Function in ALS Mouse Model
Amyotrophic Lateral Sclerosis (ALS) is the most common adult motor neuron disease, with a poor prognosis, a highly unmet therapeutic need, and a burden on health care costs. Hitherto, strategies aimed at protecting motor neurons have missed or modestly delayed ALS due to a failure in countering the irreversible muscular atrophy. We recently provided direct evidence underlying the pivotal role of macrophages in preserving skeletal muscle mass. Based on these results, we explored whether the modulation of macrophage muscle response and the enhancement of satellite cell differentiation could effectively promote the generation of new myofibers and counteract muscle dysfunction in ALS mice. For this purpose, disease progression and the survival of SOD1G93A mice were evaluated following IL-10 injections in the hindlimb skeletal muscles. Thereafter, we used ex vivo methodologies and in vitro approaches on primary cells to assess the effect of the treatment on the main pathological signatures. We found that IL-10 improved the motor performance of ALS mice by enhancing satellite cells and the muscle pro-regenerative activity of macrophages. This resulted in delayed muscle atrophy and motor neuron loss. Our findings provide the basis for a suitable adjunct multisystem therapeutic approach that pinpoints a primary role of muscle pathology in ALS
FISH WASTE, NOT A PROBLEM BUT A POSSIBLE SOLUTION: CHITOSAN EXTRACTS AND NEW PACKAGING POSSIBILITIES.
The fishing industry is one of the oldest industries in Europe and also one of the most important economic resources in the Mediterranean area. However, to date, in addition to creating considerable economic wealth, the various sectors (markets, restaurants, shops, etc.) also create significant levels of fish waste. If not processed or recycled adequately, these waste streams can lead to environmental degradation and severe pollution (Gao et al., 2018). Although today fish waste is considered a potential resource to generate high-added value, current practices in the fishing industry do not fully exploit its biological potential. Amongst the various possibilities for reuse, the production of biodegradable polymers emerges as a point of considerable interest for the food industry in the development of packaging materials and in order to improve the quality and appearance of food products (Elsabee and Abdou, 2013). In this context, chitosan, a polysaccharide of natural origin, has been experimentally used to produce edible packaging films due to its antimicrobial activity and physical-mechanical properties (Peng and Li, 2014). It is obtained from chitin, one of the most abundant natural polysaccharides and a typical component of the exoskeleton of crustaceans, molluscs and insects, and fungal cell walls (Sivaramakrishna et al., 2020). Although good progress has been made in the production of chitosan biofilms, the type of packaging that can be obtained still needs to be perfected. This study, supported by the EU Interreg Italia-Malta V-A project Bythos – Biotechnologies for Human Health and Blue Growth (C1-1.1-9), shows the preliminary results from the production of chitosan biofilms and the potential for improvement. For the first time, chitosan biofilms were produced from the head part of the exoskeleton of Aristaeomorpha foliacea, a species of considerable economic interest in the Sicilian fishing sector. Methods of extraction and purification of chitosan were developed, and the biological activities of the biofilms were evaluated. The biofilms demonstrated an antibacterial potential against Gram-positive and Gram-negative indicator strains, thus constituting a possible resource against microbial and chemical contamination in the food industries. Although further research is needed to identify new packaging methods and natural compounds that could improve the physical properties and antibacterial/antioxidant activities of the films, the possibility to reuse waste from this leading species in the Sicilian economy plays a significant role from the perspective of sustainable development and green economy
Chitosan Film Functionalized with Grape Seed Oil—Preliminary Evaluation of Antimicrobial Activity
Although the fishing and wine industries undoubtedly contribute significantly to the
economy, they also generate large waste streams with considerable repercussions on both economic
and environmental levels. Scientific literature has shown products can be extracted from these streams
which have properties of interest to the cosmetics, pharmaceutical and food industries. Antimicrobial
activity is undoubtedly among the most interesting of these properties, and particularly useful in
the production of food packaging to increase the shelf life of food products. In this study, film
for food packaging was produced for the first time using chitosan extracted from the exoskeletons
of red shrimp (Aristomorpha foliacea) and oil obtained from red grape seeds (Vitis vinifera). The
antimicrobial activity of two films was analyzed: chitosan-only film and chitosan film with the
addition of red grape seed oil at two different concentrations (0.5 mL and 1 mL). Our results showed
noteworthy antimicrobial activity resulting from functionalized chitosan films; no activity was
observed against pathogen and spoilage Gram-positive and Gram-negative bacteria, although the
antimicrobial effects observed were species-dependent. The preliminary results of this study could
contribute to developing the circular economy, helping to promote the reuse of waste to produce
innovative films for food packagin
CXCL13/CXCR5 signalling is pivotal to preserve motor neurons in amyotrophic lateral sclerosis
Background: CXCL13 is a B and T lymphocyte chemokine that mediates neuroinflammation through its receptor CXCR5. This chemokine is highly expressed by motoneurons (MNs) in Amyotrophic Lateral Sclerosis (ALS) SOD1G93A (mSOD1) mice during the disease, particularly in fast-progressing mice. Accordingly, in this study, we investigated the role of this chemokine in ALS. Methods: We used in vitro and in vivo experimental paradigms derived from ALS mice and patients to investigate the expression level and distribution of CXCL13/CXCR5 axis and its role in MN death and disease progression. Moreover, we compared the levels of CXCL13 in the CSF and serum of ALS patients and controls. Findings: CXCL13 and CXCR5 are overexpressed in the spinal MNs and peripheral axons in mSOD1 mice. CXCL13 inhibition in the CNS of ALS mice resulted in the exacerbation of motor impairment (n = 4/group;Mean_Diff.=27.81) and decrease survival (n = 14_Treated:19.2 ± 1.05wks, n = 17_Controls:20.2 ± 0.6wks; 95% CI: 0.4687–1.929). This was corroborated by evidence from primary spinal cultures where the inhibition or activation of CXCL13 exacerbated or prevented the MN loss. Besides, we found that CXCL13/CXCR5 axis is overexpressed in the spinal cord MNs of ALS patients, and CXCL13 levels in the CSF discriminate ALS (n = 30) from Multiple Sclerosis (n = 16) patients with a sensitivity of 97.56%. Interpretation: We hypothesise that MNs activate CXCL13 signalling to attenuate CNS inflammation and prevent the neuromuscular denervation. The low levels of CXCL13 in the CSF of ALS patients might reflect the MN dysfunction, suggesting this chemokine as a potential clinical adjunct to discriminate ALS from other neurological diseases. Funding: Vaccinex, Inc.; Regione Lombardia (TRANS-ALS
FSGS collapsing variant during anabolic steroid abuse: Case Report
Anabolic Androgenic Steroids (AAS) is an hormone family whose use has considerably increased among body-builders during the last decades. The AAS abuse, especially associated with other drugs or nutritional supplements and protein loads, may cause a variety of pathologies to several organs with a mechanism related to dosage, timing and substance. The kidney is the main metabolizer of these drugs and it can be acutely or chronically damaged with ESKD. The literature reports some cases of Focal Segmental Glomerulosclerosis (FSGS) in body-builders who abused of AAS. However, the link is not well understood and limited to some case-studies. In this paper, we report the case of a young body-builder who developed a FSGS collapsing variant with ESKD after prolonged abuse of AAS and a strongly hyperproteic diet and other dietary supplements. The patient underwent a genetic test because of the rapid and irreversibile onset of ESKD. The test showed a gene mutation of ACTN4, predisposing and causal of some genetic forms of FSGS. It was a very complex case, caused by several factors. The mutant protein of ACTN4 gene makes most vulnerable the cytoskeleton of the podocytes to external disturbances. That would explain why in those patients where the mutation has occurred, only those patients subject to "unfavorable environmental conditions", like the abuse of AAS, can develop a disease