141 research outputs found
Psichiatria e bioetica. Un rapporto critico, uno stimolo alla riflessione
In the western world, especially in Italy, also legal attention to bioethical aspects is increasingly taking on importance in the debate at the medical, political and public level. In this debate, Psychiatry, as a scientific discipline closely integrated with the human and cultural, is underrepresented, little questioned on the many psychopathologal issues closely related to ethical aspects on complex themes. Against this background, Rivista di psichiatria, always keen to these topics, is designed to be a very special space for discussion with all the experts involved in mental health
L-dopa and dopamine-(R)-alpha-lipoic acid conjugates as multifunctional codrugs with antioxidant properties
A series of multifunctional codrugs (1-4), obtained by joining L-Dopa (LD) and dopamine (DA) with
(R)-R-lipoic acid (LA), was synthesized and evaluated as potential codrugs with antioxidant and iron-chelating
properties. These multifunctional molecules were synthesized to overcome the pro-oxidant effect associated
with LD therapy. The physicochemical properties, together with the chemical and enzymatic stabilities of
synthesized compounds, were evaluated in order to determine both their stability in aqueous medium and
their sensitivity in undergoing enzymatic cleavage by rat and human plasma to regenerate the original drugs.
The new compounds were tested for their radical scavenging activities, using a test involving the Fe (II)-
H2O2-induced degradation of deoxyribose, and to evaluate peripheral markers of oxidative stress such as
plasmatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the plasma.
Furthermore, we showed the central effects of compounds 1 and 2 on spontaneous locomotor activity of
rats in comparison with LD-treated animals. From the results obtained, compounds 1-4 appeared stable at
a pH of 1.3 and in 7.4 buffered solution; in 80% human plasma they were turned into DA and LD. Codrugs
1-4 possess good lipophilicity (log P > 2 for all tested compounds). Compounds 1 and 2 seem to protect
partially against the oxidative stress deriving from auto-oxidation and MAO-mediated metabolism of DA.
This evidence, together with the “in vivo” dopaminergic activity and a sustained release of the parent drug
in human plasma, allowed us to point out the potential advantages of using 1 and 2 rather than LD in
treating pathologies such as Parkinson’s disease, characterized by an evident decrease of DA concentration
in the brain
Synthesis and study of L-dopa-glutathione codrugs as new anti-Parkinson agents with free radical scavenging properties
Nanoparticulate peptide delivery exclusively to the brain produces tolerance free analgesia
This is the final version. Available on open access from Elsevier via the DOI in this recordThe delivery of peptide drugs to the brain is challenging, principally due to the blood brain barrier and the low metabolic stability of peptides. Exclusive delivery to the brain with no peripheral exposure has hitherto not been demonstrated with brain quantification data. Here we show that polymer nanoparticles encapsulating leucine5-enkephalin hydrochloride (LENK) are able to transport LENK exclusively to the brain via the intranasal route, with no peripheral exposure and nanoparticle localisation is observed within the brain parenchyma. Animals dosed with LENK nanoparticles (NM0127) showed a strong anti-nociceptive response in multiple assays of evoked and on going pain whereas animals dosed intranasally with LENK alone were unresponsive. Animals did not develop tolerance to the anti-hyperalgesic activity of NM0127 and NM0127 was active in morphine tolerant animals. A microparticulate formulation of clustered nanoparticles was prepared to satisfy regulatory requirements for nasal dosage forms and the polymer nanoparticles alone were found to be biocompatible, via the nasal route, on chronic dosing.The UK Engineering and Physical Sciences Research Council(EP/K502340/1), Nanomerics Ltd.(NM12TSB-NPP) and Innovate UK(16939-124181) are acknowledged for funding
Codrugs linking L-Dopa and sulfur-containing antioxidants: new pharmacological tools against Parkinson’s Disease
A series of multifunctional codrugs (1-6) were synthesized to overcome the pro-oxidant effect associated with L-dopa (LD) therapy. Target compounds release LD and dopamine (DA) in human plasma after enzymatic hydrolysis, displaying an antioxidant effect superior to that of N-acetylcysteine (NAC). After intracerebroventricular injection of codrug 4, the levels of DA in the striatum were higher than those in LD-treated groups, indicating that this compound has a longer half-life in brain than LD
The neurotoxin DSP-4 dysregulates the locus coeruleus-norepinephrine system and recapitulates molecular and behavioral aspects of prodromal neurodegenerative disease
The noradrenergic locus coeruleus (LC) is among the earliest sites of tau and α-synuclein pathology in Alzheimer\u27s disease (AD) and Parkinson\u27s disease (PD), respectively. The onset of these pathologies coincides with loss of noradrenergic fibers in LC target regions and the emergence of prodromal symptoms including sleep disturbances and anxiety. Paradoxically, these prodromal symptoms are indicative of a noradrenergic hyperactivity phenotype, rather than the predicted loss of norepinephrine (NE) transmission following LC damage, suggesting the engagement of complex compensatory mechanisms. Because current therapeutic efforts are targeting early disease, interest in the LC has grown, and it is critical to identify the links between pathology and dysfunction. We employed the LC-specific neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4), which preferentially damages LC axons, to model early changes in the LC-NE system pertinent to AD and PD in male and female mice. DSP-4 (two doses of 50 mg/kg, one week apart) induced LC axon degeneration, triggered neuroinflammation and oxidative stress, and reduced tissue NE levels. There was no LC cell death or changes to LC firing, but transcriptomics revealed reduced expression of genes that define noradrenergic identity and other changes relevant to neurodegenerative disease. Despite the dramatic loss of LC fibers, NE turnover and signaling were elevated in terminal regions and were associated with anxiogenic phenotypes in multiple behavioral tests. These results represent a comprehensive analysis of how the LC-NE system responds to axon/terminal damage reminiscent of early AD and PD at the molecular, cellular, systems, and behavioral levels, and provides potential mechanisms underlying prodromal neuropsychiatric symptoms
Anti-bacterial activity of inorganic nanomaterials and their antimicrobial peptide conjugates against resistant and non-resistant pathogens
This review details the antimicrobial applications of inorganic nanomaterials of mostly metallic form, and the augmentation of activity by surface conjugation of peptide ligands. The review is subdivided into three main sections, of which the first describes the antimicrobial activity of inorganic nanomaterials against gram-positive, gram-negative and multidrug-resistant bacterial strains. The second section highlights the range of antimicrobial peptides and the drug resistance strategies employed by bacterial species to counter lethality. The final part discusses the role of antimicrobial peptide-decorated inorganic nanomaterials in the fight against bacterial strains that show resistance. General strategies for the preparation of antimicrobial peptides and their conjugation to nanomaterials are discussed, emphasizing the use of elemental and metallic oxide nanomaterials. Importantly, the permeation of antimicrobial peptides through the bacterial membrane is shown to aid the delivery of nanomaterials into bacterial cells. By judicious use of targeting ligands, the nanomaterial becomes able to differentiate between bacterial and mammalian cells and, thus, reduce side effects. Moreover, peptide conjugation to the surface of a nanomaterial will alter surface chemistry in ways that lead to reduction in toxicity and improvements in biocompatibility
Preparation of mupirocin-loaded polymeric nanocapsules using essential oil of rosemary
Abstract The purpose of this study was to prepare and characterize mupirocin-loaded polymeric nanocapsules using two different oils and to develop and validate an analytical method for quantitative determination by high performance liquid chromatography. The mean size of the nanoparticles was 233.05 nm and 275.03 nm for nanocapsules with a rosemary oil like oily core and caprylic/capric triglyceride, respectively, and a good polydispersity index below 0.25 for both formulations. The nanocapsules showed good stability when stored at 40 ºC and room temperature for 30 days. The quantitative method was performed with a mobile phase consisting of ammonium ammonium acetate (0.05 M adjusted to pH 5.0 with acetic acid) and acetonitrile 60:40 (v/v); the flow rate was 0.8 mL/min, UV detection at 230 nm. The analytical method was linear in the range of 5.0-15.0 µg/mL, specific for both oils, accurate, precise (intermediate precision RSD = 1.68% and repeatability RSD = 0.81%) and robust under the evaluated conditions. Therefore, this method can be performed for quantification of mupirocin in polymeric nanocapsules containing both oils
CoViD-19 and stress in the pandemic: "sanity is not statistical"
CoViD-19 pandemic is causing serious consequences on mental health, consequences that are considered that bad that World Health Organization has affirmed that mental health defence is priority in this particular moment of development of pandemic. In light of this alertness, what we are interested in approaching in this work, is the specific stress condition caused by pandemic, which underlies and precedes the described classification of diseases and which is going towards an increase in the entire world, including . The stress caused by pandemic is a new condition in comparison with what is known in clinical practice and with what is included in the classification of mental disorder. The ongoing stress condition and the mixture of different types of unconventional stress, which not only hits the present but also disrupts the future, create an entirely new form of clinical condition given by pandemic
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