Different pH requirements are associated with divergent inhibitory effects of chloroquine on human and avian influenza A viruses

Chloroquine is a 4-aminoquinoline previously used in malaria therapy and now becoming an emerging investigational antiviral drug due to its broad spectrum of antiviral activities. To explore whether the low pH-dependency of influenza A viruses might affect the antiviral effects of chloroquine at clinically achievable concentrations, we tested the antiviral effects of this drug on selected human and avian viruses belonging to different subtypes and displaying different pH requirements. Results showed a correlation between the responses to chloroquine and NH4Cl, a lysosomotropic agent known to increase the pH of intracellular vesicles. Time-of-addition experiments showed that the inhibitory effect of chloroquine was maximal when the drug had been added at the time of infection and was lost after 2 h post-infection. This timing approximately corresponds to that of virus/cell fusion. Moreover, there was a clear correlation between the EC50 of chloroquine in vitro and the electrostatic potential of the HA subunit (HA2) mediating the virus/cell fusion process. Overall, the present study highlights the critical importance of a host cell factor such as intravesicular pH in determining the anti-influenza activity of chloroquine and other lysosomotropic agents

Human immunodeficiency virus integrase inhibitors efficiently suppress feline immunodeficiency virus replication in vitro and provide a rationale to redesign antiretroviral treatment for feline AIDS

<p>Abstract</p> <p>Background</p> <p>Treatment of feline immunodeficiency virus (FIV) infection has been hampered by the absence of a specific combination antiretroviral treatment (ART). Integrase strand transfer inhibitors (INSTIs) are emerging as a promising new drug class for HIV-1 treatment, and we evaluated the possibility of inhibiting FIV replication using INSTIs.</p> <p>Methods</p> <p>Phylogenetic analysis of lentiviral integrase (IN) sequences was carried out using the PAUP* software. A theoretical three-dimensional structure of the FIV IN catalytic core domain (CCD) was obtained by homology modeling based on a crystal structure of HIV-1 IN CCD. The interaction of the transferred strand of viral DNA with the catalytic cavity of FIV IN was deduced from a crystal structure of a structurally similar transposase complexed with transposable DNA. Molecular docking simulations were conducted using a genetic algorithm (GOLD). Antiviral activity was tested in feline lymphoblastoid MBM cells acutely infected with the FIV Petaluma strain. Circular and total proviral DNA was quantified by real-time PCR.</p> <p>Results</p> <p>The calculated INSTI-binding sites were found to be nearly identical in FIV and HIV-1 IN CCDs. The close similarity of primate and feline lentivirus IN CCDs was also supported by phylogenetic analysis. In line with these bioinformatic analyses, FIV replication was efficiently inhibited in acutely infected cell cultures by three investigational INSTIs, designed for HIV-1 and belonging to different classes. Of note, the naphthyridine carboxamide INSTI, L-870,810 displayed an EC₅₀in the low nanomolar range. Inhibition of FIV integration <it>in situ </it>was shown by real-time PCR experiments that revealed accumulation of circular forms of FIV DNA within cells treated with L-870,810.</p> <p>Conclusion</p> <p>We report a drug class (other than nucleosidic reverse transcriptase inhibitors) that is capable of inhibiting FIV replication <it>in vitro</it>. The present study helped establish L-870,810, a compound successfully tested in human clinical trials, as one of the most potent anti-FIV agents ever tested <it>in vitro</it>. This finding may provide new avenues for treating FIV infection and contribute to the development of a small animal model mimicking the effects of ART in humans.</p

Headache Related Alterations of Visual Processing in Migraine Patients.

peer reviewedMigraine is characterized by an increased sensitivity to visual stimuli that worsens during attacks. Recent evidence has shown that feedforward volleys carrying incoming visual information induce high-frequency (gamma) oscillations in the visual cortex, while feedback volleys arriving from higher order brain areas induce oscillatory activity at lower frequencies (theta/alpha/low beta). We investigated visually induced high (feedforward) and low (feedback) frequency activations in healthy subjects and various migraine patients. Visual evoked potentials from 20 healthy controls and 70 migraine patients (30 interictal and 20 ictal episodic migraineurs, 20 chronic migraineurs) were analyzed in the frequency domain. We compared power in the theta-alpha-low beta and gamma range between groups, and searched for correlations between the low-to-high frequency activity ratio and number of monthly headache and migraine days. Compared to healthy controls, interictal migraine patients had increased visually induced low frequency (feedback) activity. Conversely, ictal and chronic migraine patients showed an augmented gamma band (feedforward) power. The low-frequency-to-gamma (feedback/feedforward) activity ratio correlated negatively with monthly headache days and tended to do so with migraine days. Our findings show that visual processing is differentially altered depending on migraine cycle and type. Feedback control from higher order cortical areas predominates interictally in episodic migraine while migraine attacks and chronic migraine are associated with enhanced incoming afferent activity, confirming their similar electrophysiological profile. The presence of headache is associated with proportionally higher gamma (feedforward) activities. PERSPECTIVE: This study provides an insight into the pathophysiology of migraine headache from the perspective of cortical sensory processing dynamics. Patients with migraine present alterations in feedback and feedforward visual signaling that differ with the presence of headache

Subliminal versus supraliminal stimuli activate neural responses in anterior cingulate cortex, fusiform gyrus and insula:a meta-analysis of fMRI studies

Background: Non-conscious neural activation may underlie various psychological functions in health and disorder. However, the neural substrates of non-conscious processing have not been entirely elucidated. Examining the differential effects of arousing stimuli that are consciously, versus unconsciously perceived will improve our knowledge of neural circuitry involved in non-conscious perception. Here we conduct preliminary analyses of neural activation in studies that have used both subliminal and supraliminal presentation of the same stimulus. Methods: We use Activation Likelihood Estimation (ALE) to examine functional Magnetic Resonance Imaging (fMRI) studies that uniquely present the same stimuli subliminally and supraliminally to healthy participants during functional magnetic resonance imaging (fMRI). We included a total of 193 foci from 9 studies representing subliminal stimulation and 315 foci from 10 studies representing supraliminal stimulation. Results: The anterior cingulate cortex is significantly activated during both subliminal and supraliminal stimulus presentation. Subliminal stimuli are linked to significantly increased activation in the right fusiform gyrus and right insula. Supraliminal stimuli show significantly increased activation in the left rostral anterior cingulate. Conclusions: Non-conscious processing of arousing stimuli may involve primary visual areas and may also recruit the insula, a brain area involved in eventual interoceptive awareness. The anterior cingulate is perhaps a key brain region for the integration of conscious and non-conscious processing. These preliminary data provide candidate brain regions for further study in to the neural correlates of conscious experience

Cyclophilin C-associated protein (CyCAP) knock-out mice spontaneously develop colonic mucosal hyperplasia and exaggerated tumorigenesis after treatment with carcinogen azoxymethane1

<p>Abstract</p> <p>Background</p> <p>The discovery of a "serrated neoplasia pathway" has highlighted the role of hyperplastic lesions of the colon as the significant precursor of colorectal adenocarcinoma. In mice, hyperplasia of the colonic mucosa is a regular phenomenon after a challenge with colonic carcinogens indicating that mucosal hyperproliferation and thickening, even without cytological dysplasia, represents an early pre-malignant change. Cyclophilin C-associated protein (CyCAP) has been described to down-modulate endotoxin signaling in colorectal murine mucosa and is a murine orthologue of the tumor-associated antigen 90 K (TAA90K)/mac-2-binding protein.</p> <p>Methods</p> <p>Female Balb/c wild-type (WT) and CyCAP knock-out (KO) mice (6–8 weeks old) were administered 2 or 6 weekly subcutaneous injections of azoxymethane. The animals were evaluated post-injection at six weeks for aberrant crypt foci (ACF) study and at five months for colon tumor measurement. The thickness of the colon crypts was measured in microns and the number of colonocytes per crypt was also determined in well-oriented crypts. Morphometric analyses of the colon mucosa were also performed in untreated 6–8 weeks old KO and WT animals. Formalin-fixed/paraffin-embedded colon sections were also studied by immunohistochemistry to determine the Ki-67 proliferation fraction of the colon mucosa, β-catenin cellular localization, cyclin D1, c-myc, and lysozyme in Paneth cells.</p> <p>Results</p> <p>Cyclophilin C-associated protein (CyCAP)^-/-mice, spontaneously developed colonic mucosal hyperplasia early in life compared to wild-type mice (WT) (p < 0.0001, T-test) and crypts of colonic mucosa of the (CyCAP)^-/-mice show higher proliferation rate (p = 0.039, Mann-Whitney Test) and larger number of cyclin D1-positive cells (p < 0.0001, Mann-Whitney Test). Proliferation fraction and cyclin D1 expression showed positive linear association (p = 0.019, Linear-by-Linear Association). The hyperplasia was even more pronounced in CyCAP^-/-mice than in WT after challenge with azoxymethane (p = 0.005, T-test). The length of the crypts (r = 0.723, p = 0.018, Spearman Correlation) and the number of colonocytes per crypt (r = 0.863, p = 0.001, Spearman Correlation) in non-tumorous areas were positively associated with azoxymethane-induced number of tumors. CyCAP^-/-developed larger numbers of tumors than WT animals (p = 0.003, T-Test) as well as overall larger tumor mass (p = 0.016, T-Test). Membranous β-catenin was focally overexpressed in KO mice including proliferative zone of the crypts.</p> <p>Conclusion</p> <p>CyCAP^-/-represent the first described model of spontaneous colonic mucosal hyperplasia. We conclude that CyCAP-deficient mice spontaneously and after challenge with carcinogen develop significantly more colorectal mucosal hyperplasia, an early stage in murine colonic carcinogenesis.</p

Distinct HR expression patterns significantly affect the clinical behavior of metastatic HER2+ breast cancer and degree of benefit from novel anti-HER2 agents in the real world setting

We analyzed data from 738 HER2\u2010positive metastatic breast cancer (mbc) patients treated with pertuzumab\u2010based regimens and/or T\u2010DM1 at 45 Italian centers. Outcomes were explored in relation to tumor subtype assessed by immunohistochemistry (IHC). The median progression free survival at first\u2010line (mPFS1) was 12 months. Pertuzumab as first\u2010line conferred longer mPFS1 compared to other first\u2010line treatments (16 vs 9 months, p=0.0001), regardless of IHC subtype. Median PFS in second\u2010line (mPFS2) was 7 months, with no difference by IHC subtype, but it was more favorable with T\u2010DM1 compared to other agents (7 vs 6 months, p=0.03). There was no PFS2 gain in patients with tumors expressing both hormonal receptors (HRs) (p=0.17), while a trend emerged for tumors with one HR (p=0.05). Conversely, PFS2 gain was significant in HRs\u2010negative tumors (p=0.04). Median overall survival (mOS) was 74 months, with no significant differences by IHC subtypes. Survival rates at 2 and 3 years in patients treated with T\u2010DM1 in second\u2010line following pertuzumab were significantly lower compared to pertuzumab\u2010na\uefve patients(p=0.01). When analyzed by IHC subtype, the outcome was confirmed if both HRs or no HRs were expressed (p=0.02 and p=0.006, respectively). Our results confirm that HRs expression impacts the clinical behavior and novel treatment\u2010related outcomes of HER2\u2010positive tumors when treatment sequences are considered. Moreover, multivariate analysis showed that HRs expression had no effect on PFS and OS. Further studies are warranted to confirm our findings and clarify the interplay between HER2 and estrogen receptor (ER) pathways in HER2\u2010positive (mbc) patients

The network model of depression as a basis for new therapeutic strategies for treating major depressive disorder in Parkinson’s disease

The high prevalence of major depressive disorder in people with Parkinson's disease, its negative impact on health-related quality of life and the low response rate to conventional pharmacological therapies call to seek innovative treatments. Here, we review the new approaches for treating major depressive disorder in patients with Parkinson's disease within the framework of the network model of depression. According to this model, major depressive disorder reflects maladaptive neuronal plasticity. Non-invasive brain stimulation using high frequency repetitive transcranial magnetic stimulation over the prefrontal cortex has been proposed as a feasible and effective strategy with minimal risk. The neurobiological basis of its therapeutic effect may involve neuroplastic modifications in limbic and cognitive networks. However, the way this networks reorganize might be strongly influenced by the environment. To address this issue, we propose a combined strategy that includes non-invasive brain stimulation together with cognitive and behavioral interventions

Brain mechanisms underlying automatic and unconscious control of motor action

Are we in command of our motor acts? The popular belief holds that our conscious decisions are the direct causes of our actions. However, overwhelming evidence from neurosciences demonstrates that our actions are instead largely driven by brain processes that unfold outside of our consciousness. To study these brain processes, scientists have used a range of different functional brain imaging techniques and experimental protocols, such as subliminal priming. Here, we review recent advances in the field and propose a theoretical model of motor control that may contribute to a better understanding of the pathophysiology of movement disorders such as Parkinson’s disease

Sviluppo di un programma per il calcolo del termine sorgente ai fini della valutazione del rischio

Nel laboratorio PQAT dell’istituto IQS School of Engineering di Barcellona si realizzano analisi quantitative di rischio per gli stabilimenti chimici classificati, secondo la direttiva Seveso, come stabilimenti a rischio di incidente rilevante. In fase di valutazione è necessario seguire un procedimento metodico che prevede fasi di calcolo manuali coadiuvate dall’utilizzo di software. La normativa catalana specifica che possono essere impiegati software commerciali come ALOHA e EFFECTS per la quantificazione del termine sorgente, mentre per la valutazione delle conseguenze fisiche legate a scenari di dispersione tossica e la generazione delle curve isorischio il gruppo IQS utilizza un codice proprio implementato in MATLAB. Col fine di rendere il procedimento completamente automatizzato, così da eliminare le fasi iniziali di calcolo supportate dai software, è stato introdotto nel programma generale un codice appositamente sviluppato in MATLAB per la quantificazione del termine sorgente in seguito a rilasci accidentali di sostanza in fase liquida. Il codice sostituisce il lavoro svolto dal software EFFECTS e fornisce informazioni relative alla quantità di sostanza rilasciata in atmosfera e allo stato fisico del rilascio, da cui è possibile procedere alla modellazione della dispersione e alla valutazione del rischio finale. Col fine di comprovarne il corretto funzionamento, il programma così ottenuto è stato utilizzato per simulare alcuni casi di rilascio relativi a serbatoi di sostanze pericolose stoccate in un’industria chimica situata nel territorio catalano. Il codice oltre ad essersi dimostrato decisamente accurato e completo, ha permesso una notevole riduzione in termini di tempo e complessità delle operazioni da svolgere per operare le analisi di valutazione del rischio secondo la metodologia IQS