68 research outputs found
Determination of 6-Monoacetyl-Morphine (6-MAM) in Brain Samples from Heroin Fatalities
Objective: Post-mortem brain samples from 15 deceased patients whose death was heroin related, were analyzed to determine 6-monoacetyl-morphine (6-MAM) concentrations. The samples belonged to people died between 2008 and 2014. The first eight samples were also analyzed in 2012 to determine only morphine and codeine levels. Method: A GC/MS method was studied in order to enhance sensitivity, thus helping the determination of 6-MAM whose detection is in most cases difficult because of the complexity of the biological matrix. The analytical method was validated using deuterated internal standards (IS-D3, morphine-D3 and codeine-D3) and it showed adequate specificity, linearity, LOD, LOQ precision and accuracy for the determination of the analyte of interest. Results: 6-MAM was evidenced only in the more recent samples, thus pointing out its low stability. Its concentration ranged from 15.6 to 28.9 ng/g. Morphine and codeine was also determined and a comparison was carried out between the blood and the brain levels of the three analytes. Moreover a parallel was established between the concentrations of morphine and codeine found in the brain in 2012 and 2015. Conclusion: 6-MAM determination in the brain is particularly important when discriminating between morphine assumption and heroin abuse. In fact in the cases in which it is not detectable in the blood it can be present in the brain. It was noticed that the concentrations of morphine found in the brain in 2015 are higher respect to the levels of 2012; a possible explanation could be that 6-MAM originally present in the brain has hydrolyzed to morphine, thus increasing its levels
Leukotrienes inhibit early stages of HIV-1 infection in monocyte-derived microglia-like cells
<p>Abstract</p> <p>Background</p> <p>Microglia are one of the main cell types to be productively infected by HIV-1 in the central nervous system (CNS). Leukotriene B<sub>4 </sub>(LTB<sub>4</sub>) and cysteinyl-leukotrienes such as LTC<sub>4 </sub>are some of the proinflammatory molecules produced in infected individuals that contribute to neuroinflammation. We therefore sought to investigate the role of leukotrienes (LTs) in HIV-1 infection of microglial cells.</p> <p>Methods</p> <p>To evaluate the role of LTs on HIV-1 infection in the CNS, monocyte-derived microglial-like cells (MDMis) were utilized in this study. Leukotriene-treated MDMis were infected with either fully replicative brain-derived HIV-1 isolates (YU2) or R5-tropic luciferase-encoding particles in order to assess viral production and expression. The efficacy of various steps of the replication cycle was evaluated by means of p24 quantification by ELISA, luciferase activity determination and quantitative real-time polymerase chain reaction (RT-PCR).</p> <p>Results</p> <p>We report in this study that virus replication is reduced upon treatment of MDMis with LTB<sub>4 </sub>and LTC<sub>4</sub>. Additional experiments indicate that these proinflammatory molecules alter the pH-independent entry and early post-fusion events of the viral life cycle. Indeed, LT treatment induced a diminution in integrated proviral DNA while reverse-transcribed viral products remained unaffected. Furthermore, decreased C-C chemokine receptor type 5 (CCR5) surface expression was observed in LT-treated MDMis. Finally, the effect of LTs on HIV-1 infection in MDMis appears to be mediated partly via a signal transduction pathway involving protein kinase C.</p> <p>Conclusions</p> <p>These data show for the first time that LTs influence microglial cell infection by HIV-1, and may be a factor in the control of viral load in the CNS.</p
When Cytokinin, a Plant Hormone, Meets the Adenosine A2A Receptor: A Novel Neuroprotectant and Lead for Treating Neurodegenerative Disorders?
It is well known that cytokinins are a class of phytohormones that promote cell division in plant roots and shoots. However, their targets, biological functions, and implications in mammalian systems have rarely been examined. In this study, we show that one cytokinin, zeatin riboside, can prevent pheochromocytoma (PC12) cells from serum deprivation-induced apoptosis by acting on the adenosine A2A receptor (A2A-R), which was blocked by an A2A-R antagonist and a protein kinase A (PKA) inhibitor, demonstrating the functional ability of zeatin riboside by mediating through A2A-R signaling event. Since the A2A-R was implicated as a therapeutic target in treating Huntington’s disease (HD), a cellular model of HD was applied by transfecting mutant huntingtin in PC12 cells. By using filter retardation assay and confocal microscopy we found that zeatin riboside reversed mutant huntingtin (Htt)-induced protein aggregations and proteasome deactivation through A2A-R signaling. PKA inhibitor blocked zeatin riboside-induced suppression of mutant Htt aggregations. In addition, PKA activated proteasome activity and reduced mutant Htt protein aggregations. However, a proteasome inhibitor blocked both zeatin riboside-and PKA activator-mediated suppression of mutant Htt aggregations, confirming mediation of the A2A-R/PKA/proteasome pathway. Taken together, zeatin riboside might have therapeutic potential as a novel neuroprotectant and a lead for treating neurodegenerative disorders
Mechanisms and mechanics of cell competition in epithelia
When fast-growing cells are confronted with slow-growing cells in a mosaic tissue, the slow-growing cells are often progressively eliminated by apoptosis through a process known as cell competition. The underlying signalling pathways remain unknown, but recent findings have shown that cell crowding within an epithelium leads to the eviction of cells from the epithelial sheet. This suggests that mechanical forces could contribute to cell elimination during cell competition
Endothelial dysfunction in Coronavirus disease 2019 (COVID-19): Gender and age influences
Several risk factors are associated with a worse outcome for COVID-19 patients; the most recognized are demographic characteristics such as older age and male gender, and pre-existing cardiovascular conditions. About the latter, hypertension and coronary heart disease are among the most common comorbidities recorded in infected patients, together with type 2 diabetes mellitus (T2DM). Data from Istituto Superiore di Sanit\ue0 (ISS, Italy) show that more than 68.3% of patients had hypertension, 28.2% ischemic heart disease, 22.5% atrial fibrillation, while 30.1% T2DM. Several authors suggested that cardiovascular diseases and diabetes mellitus are linked to endothelial dysfunction, and all of them are strictly related to aging. Considering the impact of the gender on the COVID-19 epidemic, even if confirmed cases from each nation are changing every day, epidemiological data clearly evidence that in men the infection causes worse outcomes compared to women. In Italy, up to 21 May, in the age range of 60\u201389 years, male deaths were 63.9% of total cases. The reason behind this difference between genders appears not clear; however, the diversity in sex-hormones and styles of life are believed to play a role in the patient's susceptibility to severe SARS-CoV-2 outcomes. It is known that the activation of endothelial estrogen receptors increases NO and decreases ROS, protecting the vascular system from angiotensin II-mediated vasoconstriction, inflammation, and ROS production. During the pandemic, joining forces is vital; thus, as people help doctors by limiting their displacements out of their houses avoiding hence the spread of the infection, doctors help patients to overcome severe SARS-CoV-2 infections by using multiple pharmacological approaches. In this context, the preservation of endothelial function and the mitigation of vascular inflammation are prominent targets, essential to reduce severe outcomes also in male older patients
Dislipidemia e aterosclerosi
Testo didattico per gli studenti universitari dei corsi di laurea in Farmacia, Chimica e Tecnologia Farmaceutiche e per tutte le lauree di area sanitaria
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