41 research outputs found
Minocycline Inhibition of Monocyte Activation Correlates with Neuronal Protection in SIV NeuroAIDS
Background: Minocycline is a tetracycline antibiotic that has been proposed as a potential conjunctive therapy for HIV-1
associated cognitive disorders. Precise mechanism(s) of minocycline’s functions are not well defined.
Methods: Fourteen rhesus macaques were SIV infected and neuronal metabolites measured by proton magnetic resonance
spectroscopy (1H MRS). Seven received minocycline (4 mg/kg) daily starting at day 28 post-infection (pi). Monocyte
expansion and activation were assessed by flow cytometry, cell traffic to lymph nodes, CD16 regulation, viral replication,
and cytokine production were studied.
Results: Minocycline treatment decreased plasma virus and pro-inflammatory CD14+CD16+ and CD14loCD16+ monocytes,
and reduced their expression of CD11b, CD163, CD64, CCR2 and HLA-DR. There was reduced recruitment of monocyte/
macrophages and productively infected cells in axillary lymph nodes. There was an inverse correlation between brain NAA/
Cr (neuronal injury) and circulating CD14+CD16+ and CD14loCD16+ monocytes. Minocycline treatment in vitro reduced SIV
replication CD16 expression on activated CD14+CD16+ monocytes, and IL-6 production by monocytes following LPS
stimulation.
Conclusion: Neuroprotective effects of minocycline are due in part to reduction of activated monocytes, monocyte traffic.
Mechanisms for these effects include CD16 regulation, reduced viral replication, and inhibited immune activation.
Citation: Campbell JH, Burdo TH, Autissier P, Bombardier JP, Westmoreland SV, et al. (2011) Minocycline Inhibition of Monocyte Activation Correlate
Proton Magnetic Resonance Spectroscopy Reveals Neuroprotection by Oral Minocycline in a Nonhuman Primate Model of Accelerated NeuroAIDS
Background: Despite the advent of highly active anti-retroviral therapy (HAART), HIV-associated neurocognitive disorders continue to be a significant problem. In efforts to understand and alleviate neurocognitive deficits associated with HIV, we used an accelerated simian immunodeficiency virus (SIV) macaque model of NeuroAIDS to test whether minocycline is neuroprotective against lentiviral-induced neuronal injury. Methodology/Principal Findings: Eleven rhesus macaques were infected with SIV, depleted of CD8+ lymphocytes, and studied until eight weeks post inoculation (wpi). Seven animals received daily minocycline orally beginning at 4 wpi. Neuronal integrity was monitored in vivo by proton magnetic resonance spectroscopy and post-mortem by immunohistochemistry for synaptophysin (SYN), microtubule-associated protein 2 (MAP2), and neuronal counts. Astrogliosis and microglial activation were quantified by measuring glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (IBA-1), respectively. SIV infection followed by CD8+ cell depletion induced a progressive decline in neuronal integrity evidenced by declining N-acetylaspartate/creatine (NAA/Cr), which was arrested with minocycline treatment. The recovery of this ratio was due to increases in NAA, indicating neuronal recovery, and decreases in Cr, likely reflecting downregulation of glial cell activation. SYN, MAP2, and neuronal counts were found to be higher in minocycline-treated animals compared to untreated animals while GFAP and IBA-1 expression were decreased compared to controls. CSF and plasma viral loads were lower in MN-treated animals. Conclusions/Significance: In conclusion, oral minocycline alleviates neuronal damage induced by the AIDS virus
Hyperbolicity of varieties of log general type
These notes provide an overview of various notions of hyperbolicity for
varieties of log general type from the viewpoint of both arithmetic and
birational geometry. The main results are based on our paper entitled
"Hyperbolicity and uniformity of varieties of log general type." They are
expanded notes from a minicourse the authors gave as part of the Geometry and
arithmetic of orbifolds workshop at UQ\'AM.Comment: Addressed some inaccuracies and typos pointed out by the referees and
some readers. Slight change of title. To appear in CRM short courses
(Arithmetic Geometry of Logarithmic Pairs and Hyperbolicity of Moduli Spaces:
Hyperbolicity in Montr\'eal
Dissipative Particle Dynamics Study of Alginate/Gelatin Aerogels Obtained by Supercritical Drying
The properties of alginate/gelatin (A/G) interpenetrated polymer networks have been studied by dissipative particle dynamics (DPD) simulations. The simulation predicted some mechanical properties of A/G blends with different A/G ratios in water. Results from new synthesized aerogels have been used to validate the range of exploitation of the DPD simulations. Good mechanical and morphological properties of the aerogels have been achieved from aerogels derived from hydrogels with water content higher than 95%. DPD simulation results indicated that an optimal shear viscosity is reached for a composition of 95% water, 3% alginate and 2% gelatin. Furthermore, this approach can be of great interest in designing novel materials