93 research outputs found
Amyloid beta peptide-induced inhibition of endothelial nitric oxide production involves oxidative stress-mediated constitutive eNOS/HSP90 interaction and disruption of agonist-mediated Akt activation
Background: Amyloid beta (A beta)-induced vascular dysfunction significantly contributes to the pathogenesis of Alzheimer\u27s disease (AD). A beta is known to impair endothelial nitric oxide synthase (eNOS) activity, thus inhibiting endothelial nitric oxide production (NO). Method: In this study, we investigated A beta-effects on heat shock protein 90 (HSP90) interaction with eNOS and Akt in cultured vascular endothelial cells and also explored the role of oxidative stress in this process. Results: Treatments of endothelial cells (EC) with A beta promoted the constitutive association of HSP90 with eNOS but abrogated agonist (vascular endothelial growth factor (VEGF))-mediated HSP90 interaction with Akt. This effect resulted in blockade of agonist-mediated phosphorylation of Akt and eNOS at serine 1179. Furthermore, A beta stimulated the production of reactive oxygen species in endothelial cells and concomitant treatments of the cells with the antioxidant N-acetyl-cysteine (NAC) prevented A beta effects in promoting HSP90/eNOS interaction and rescued agonist-mediated Akt and eNOS phosphorylation. Conclusions: The obtained data support the hypothesis that oxidative damage caused by A beta results in altered interaction of HSP90 with Akt and eNOS, therefore promoting vascular dysfunction. This mechanism, by contributing to A beta-mediated blockade of nitric oxide production, may significantly contribute to the cognitive impairment seen in AD patients
Recommended from our members
Actions and Potential Therapeutic Applications of Growth Hormone-Releasing Hormone Agonists.
Abstract
In this article, we briefly review the identification of GHRH, provide an abridged overview of GHRH antagonists, and focus on studies with GHRH agonists. Potent GHRH agonists of JI and MR class were synthesized and evaluated biologically. Besides the induction of the release of pituitary GH, GHRH analogs promote cell proliferation and exert stimulatory effects on various tissues, which express GHRH receptors (GHRH-Rs). A large body of work shows that GHRH agonists, such as MR-409, improve pancreatic β-cell proliferation and metabolic functions and facilitate engraftment of islets after transplantation in rodents. Accordingly, GHRH agonists offer a new therapeutic approach to treating diabetes. Various studies demonstrate that GHRH agonists promote repair of cardiac tissue, producing improvement of ejection fraction and reduction of infarct size in rats, reduction of infarct scar in swine, and attenuation of cardiac hypertrophy in mice, suggesting clinical applications. The presence of GHRH-Rs in ocular tissues and neuroprotective effects of GHRH analogs in experimental diabetic retinopathy indicates their possible therapeutic applications for eye diseases. Other effects of GHRH agonists, include acceleration of wound healing, activation of immune cells, and action on the central nervous system. As GHRH might function as a growth factor, we examined effects of GHRH agonists on tumors. In vitro, GHRH agonists stimulate growth of human cancer cells and upregulate GHRH-Rs. However, in vivo, GHRH agonists inhibit growth of human cancers xenografted into nude mice and downregulate pituitary and tumoral GHRH-Rs. Therapeutic applications of GHRH analogs are discussed. The development of GHRH analogs should lead to their clinical use
facial emotion recognition performance influences executive control impairment in anorexia nervosa an exploratory study
AbstractObjectivesSince evidence on executive control among women with Anorexia or Bulimia Nervosa (AN/BN) are somehow inconclusive, we aimed to explore whether performance in set-shifting in AN/BN might be influenced by Facial Emotion Recognition (FER).MethodsWe randomly recruited women with a diagnosis of AN or BN, from an Eating Disorders Outpatient Clinic in Italy, as well as healthy controls (HCs). We evaluated with established tools: diagnosis (Eating Disorder Examination- EDE-17.0), executive control (Intra-Extra Dimensional Set Shift-IED) and FER (Ekman 60 Faces Test-EK-60F). Univariate distributions by diagnostic subgroups were assessed on sociodemographic and clinical variables, which were selected for subsequent multiple linear regression analyses.ResultsWomen with AN performed significantly worse than HCs on IED adjusted total errors. HCs scored significantly better than AN and BN on EK-60F fear subscale. Although IED set shifting was associated (p = 0.008) with AN, after controlling for age, EK-60F fear subscale, alexithymia and depression (i.e., clinically relevant covariates identified a priori from the literature, or associated with AN/BN at univariate level), this association could not be confirmed.ConclusionsImpaired executive control may not be a distinctive feature in women with AN, since several clinical characteristics, including fear recognition ability, are likely to have an important role. This has significant implications for relevant interventions in AN, which should aim at also improving socio-emotional processing
Inhalation therapy in the next decade : Determinants of adherence to treatment in asthma and COPD
Peer reviewedPublisher PD
Lethal and Sublethal Responses of Hydropsyche pellucidula (Insecta, Trichoptera) to Commercial Polypropylene Microplastics after Different Preconditioning Treatments
Microplastics (MPs) pose biological and chemical hazards in aquatic and terrestrial food webs across the globe. Research on microplastic contamination has long focused on marine ecosystems, whereas the toxicological impact on freshwater organisms is still little explored. In this study, the lethal and sublethal response of the freshwater macroinvertebrate Hydropsyche pellucidula exposed to polypropylene MPs after different pre-conditioning treatments was assessed. Field samples were collected in a riverine system (Vipacco river; northeast Italy) to assess the characteristics of the MPs in the aquatic environment Both water and sediment were contaminated by MPs (3.73 ± 2.11 items m−3 per min and 3.33 ± 4.16 items dm−3, respectively). The chemical MPs composition included polystyrene, polyethylene terephthalate, polyurethane, polyamide, polypropylene, and polyethylene. Polypropylene (PP), although not the most abundant polymer recorded in the study area, was preferred over the other types according to its abundance in freshwater and H. pellucidula feeding behavior. A housing test was performed to recreate the natural conditions of larvae sampled for a reliable response to the ecotoxicological tests. The microplastics underwent either preconditioning with Vipacco River water (PP-river) and surfactant Triton X-100 (PP-sf) or no pre-treatment (PP). Submersion of microplastics in 10 µg L−1 of surfactant solution for 24 h was sufficient to induce consistent spectral changes and modify the chemical profile of the plastic surface. Mortality rate differed according to treatment: PP and PP-river > positive control > PP-sf > negative control. Integrated biomarker response (IBRv2) and analysis of oxidative stress biomarker levels showed a greater response of superoxide dismutase and lipid peroxidation (malondialdehyde) in larvae treated with PP conditioned in surfactant. Our findings enhance knowledge on the toxicity of PP and conditioning phases on H. pellucidula larvae.This research received no external funding.Peer reviewe
Determination of Lactoferrin and Immunoglobulin G in Animal Milks by New Immunosensors
Two different immunosensors, recently developed for the determination of antibacterial proteins (lactoferrin and immunoglobulin G) in buffalo milk and in other commercial animal milks samples, were used in the present study. The aim was to propose these immunosensor methods for routine control of important diet products, such as cow and goat milks, and in particular buffalo milk. To this end we employed two different kinds of immunosensors: one for the analysis of immunoglobulin G (IgG), the other was a new amperometric immunosensor for lactoferrin analysis. Lactoferrin and IgG immunosensors were also used for the determination of lactoferrin and immunoglobulin G in buffalo milk on different days of lactation
COVID-19 in rheumatic diseases in Italy: first results from the Italian registry of the Italian Society for Rheumatology (CONTROL-19)
OBJECTIVES:
Italy was one of the first countries significantly affected by the coronavirus disease 2019 (COVID-19) epidemic. The Italian Society for Rheumatology promptly launched a retrospective and anonymised data collection to monitor COVID-19 in patients with rheumatic and musculoskeletal diseases (RMDs), the CONTROL-19 surveillance database, which is part of the COVID-19 Global Rheumatology Alliance.
METHODS:
CONTROL-19 includes patients with RMDs and proven severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) updated until May 3rd 2020. In this analysis, only molecular diagnoses were included. The data collection covered demographic data, medical history (general and RMD-related), treatments and COVID-19 related features, treatments, and outcome. In this paper, we report the first descriptive data from the CONTROL-19 registry.
RESULTS:
The population of the first 232 patients (36% males) consisted mainly of elderly patients (mean age 62.2 years), who used corticosteroids (51.7%), and suffered from multi-morbidity (median comorbidities 2). Rheumatoid arthritis was the most frequent disease (34.1%), followed by spondyloarthritis (26.3%), connective tissue disease (21.1%) and vasculitis (11.2%). Most cases had an active disease (69.4%). Clinical presentation of COVID-19 was typical, with systemic symptoms (fever and asthenia) and respiratory symptoms. The overall outcome was severe, with high frequencies of hospitalisation (69.8%), respiratory support oxygen (55.7%), non-invasive ventilation (20.9%) or mechanical ventilation (7.5%), and 19% of deaths. Male patients typically manifested a worse prognosis. Immunomodulatory treatments were not significantly associated with an increased risk of intensive care unit admission/mechanical ventilation/death.
CONCLUSIONS:
Although the report mainly includes the most severe cases, its temporal and spatial trend supports the validity of the national surveillance system. More complete data are being acquired in order to both test the hypothesis that RMD patients may have a different outcome from that of the general population and determine the safety of immunomodulatory treatments
PERCHLORATES AS POWERFUL CATALYSTS IN MANY IMPORTANT ORGANIC TRANSFORMATIONS
For long times, metallic perchlorates have been considered dangerous compounds[1] in that they function as explosives and as incontrollable oxidizers.
Therefore, the fear of the great hazard connected with their manufacture and uses had prevented an extensive use both in research laboratories and in industrial processes.[2]
However, recently it has been cleared that this bad reputation is due to the mistaken association of metallic perchlorates with the oxidizing potential of perchloric acid and the pyrotechnic performances of NH4ClO4.
In this conference, we report that Magnesium and Zinc perchlorates can be used as powerful Lewis acids in several organic transformations which are commonly employed both in laboratory and industrial processes.
As depicted in the Scheme, perchlorates are able to promote a series of reactions such as:
a) Acylation of alcohols[3,4]
b) Fisher esterification[5]
c) Synthesis of b–enamino esters[6]
d) Protection of the amino group as N-Boc derivative[7]
Moreover, they can act as specific catalysts for the development of a new organic transformations. In fact, the treatment of an alcohol or a phenol with Boc2O in the presence of Mg(ClO4)2 leads to the unexpected formation of the corresponding t-butyl ethers.[8] This represents the first general method to synthesize aromatic t-butyl ethers.
In an analogous manner, the treatment of phenols with diethyl dicarbonate results in a very efficient method to produce difficulty available aryl ethyl carbonates.
Several of the above mentioned transformations can be carried out in the absence of the solvent, and often the catalyst can be easily recovered and reused without an appreciable loss of activity.
Acknowledgement
Work carried out in the framework of the National Project “Stereoselezione in Sintesi Organica. Metodologie e Applicazioni” supported by MIUR, Rome, by the University of Bologna, in the framework of “Progetto di Finanziamento Pluriennale, Ateneo di Bologna”, and by National project FIRB “Progettazione, preparazione e valutazione biologica e farmacologica di nuove molecole organiche quali potenziali farmaci”
References
[1] Schumacher, J. C. Perchlorates-Their Properties, Manufacture and Uses, ACS Monograph Series, Reinhold: New York, 1960.Author. Title[J]. Name of the journal, Year, Volume(Issue): initial page and ending page (Optional).
[2] Long, J. Chemical Health & Safety, 2002, 9, 12.
[3] Bartoli, G.; Bosco, M.; Dalpozzo, R.; Marcantoni, E.; Massaccesi, M.; Rinaldi, S.; Sambri, L. Synlett, 2003, 39.
[4] Bartoli, G.; Bosco, M.; Dalpozzo, R.; Marcantoni, E.; Massaccesi, M.; Sambri, L. Eur. J. Org. Chem. 2003, 4611.
[5] a) Gooβen, L.; Döhring, A. Adv. Synth. Catal. 2003, 345, 943; b) Bartoli, G.; Boeglin, J.; Bosco, M.; Locatelli, M.; Massaccesi, M.; Melchiorre, P.; Sambri, L. Adv. Synth. Catal. 2005, 347, 33.
[6] Bartoli, G.; Bosco, M.; Locatelli, M.; Marcantoni, E.; Melchiorre, P.; Sambri, L. Synlett 2004, 239.
[7] Bartoli, G.; Bosco, M.; Locatelli, M.; Marcantoni, E.; Massaccesi, M.; Melchiorre, P.; Sambri, L. Synlett 2004, 1794.
[8] Bartoli, G.; Bosco, M.; Locatelli, M.; Marcantoni, E.; Melchiorre, P.; Sambri, L. Org. Lett., 2004, 7, 427
- …