Replenishing IRAK-M expression in retinal pigment epithelium attenuates outer retinal degeneration.

Chronic inflammation is a constitutive component of many age-related diseases, including age-related macular degeneration (AMD). Here, we identified interleukin-1 receptor-associated kinase M (IRAK-M) as a key immunoregulator in retinal pigment epithelium (RPE) that declines during the aging process. Rare genetic variants of IRAK3, which encodes IRAK-M, were associated with an increased likelihood of developing AMD. In human samples and mouse models, IRAK-M abundance in the RPE declined with advancing age or exposure to oxidative stress and was further reduced in AMD. Irak3-knockout mice exhibited an increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M led to a disruption in RPE cell homeostasis, characterized by compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of adeno-associated virus (AAV)-expressing human IRAK3 rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in Irak3-knockout mice. Our data show that replenishment of IRAK-M in the RPE may redress dysregulated pro-inflammatory processes in AMD, suggesting a potential treatment for retinal degeneration.

Replenishing Age-Related Decline of IRAK-M Expression in Retinal Pigment Epithelium Attenuates Outer Retinal Degeneration.

Unchecked, chronic inflammation is a constitutive component of age-related diseases, including age-related macular degeneration (AMD). Here we identified interleukin-1 receptor-associated kinase (IRAK)-M as a key immunoregulator in retinal pigment epithelium (RPE) that declines with age. Rare genetic variants of IRAK-M increased the likelihood of AMD. IRAK-M expression in RPE declined with age or oxidative stress and was further reduced in AMD. IRAK-M-deficient mice exhibited increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M disrupted RPE cell homeostasis, including compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of AAV-expressing IRAK-M rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in IRAK-M-deficient mice. Our data support that replenishment of IRAK-M expression may redress dysregulated pro-inflammatory processes in AMD, thereby treating degeneration.

Systems genetics identifies miRNA-mediated regulation of host response in COVID-19.

BACKGROUND: Individuals infected with SARS-CoV-2 vary greatly in their disease severity, ranging from asymptomatic infection to severe disease. The regulation of gene expression is an important mechanism in the host immune response and can modulate the outcome of the disease. miRNAs play important roles in post-transcriptional regulation with consequences on downstream molecular and cellular host immune response processes. The nature and magnitude of miRNA perturbations associated with blood phenotypes and intensive care unit (ICU) admission in COVID-19 are poorly understood. RESULTS: We combined multi-omics profiling-genotyping, miRNA and RNA expression, measured at the time of hospital admission soon after the onset of COVID-19 symptoms-with phenotypes from electronic health records to understand how miRNA expression contributes to variation in disease severity in a diverse cohort of 259 unvaccinated patients in Abu Dhabi, United Arab Emirates. We analyzed 62 clinical variables and expression levels of 632 miRNAs measured at admission and identified 97 miRNAs associated with 8 blood phenotypes significantly associated with later ICU admission. Integrative miRNA-mRNA cross-correlation analysis identified multiple miRNA-mRNA-blood endophenotype associations and revealed the effect of miR-143-3p on neutrophil count mediated by the expression of its target gene BCL2. We report 168 significant cis-miRNA expression quantitative trait loci, 57 of which implicate miRNAs associated with either ICU admission or a blood endophenotype. CONCLUSIONS: This systems genetics study has given rise to a genomic picture of the architecture of whole blood miRNAs in unvaccinated COVID-19 patients and pinpoints post-transcriptional regulation as a potential mechanism that impacts blood traits underlying COVID-19 severity. The results also highlight the impact of host genetic regulatory control of miRNA expression in early stages of COVID-19 disease.

An in vitro model of chronic wounding and its implication for age-related macular degeneration.

Degeneration of the retinal pigment epithelium (RPE) plays a central role in age-related macular degeneration (AMD). Throughout life, RPE cells are challenged by a variety of cytotoxic stressors, some of which are cumulative with age and may ultimately contribute to drusen and lipofuscin accumulation. Stressors such as these continually damage RPE cells resulting in a state of chronic wounding. Current cell-based platforms that model a state of chronic RPE cell wounding are limited, and the RPE cellular response is not entirely understood. Here, we used the electric cell-substrate impedance sensing (ECIS) system to induce a state of acute or chronic wounding on differentiated human fetal RPE cells to analyze changes in the wound repair response. RPE cells surrounding the lesioned area employ both cell migration and proliferation to repair wounds but fail to reestablish their original cell morphology or density after repetitive wounding. Chronically wounded RPE cells develop phenotypic AMD characteristics such as loss of cuboidal morphology, enlarged size, and multinucleation. Transcriptomic analysis suggests a systemic misregulation of RPE cell functions in bystander cells, which are not directly adjacent to the wound. Genes associated with the major RPE cell functions (LRAT, MITF, RDH11) significantly downregulate after wounding, in addition to differential expression of genes associated with the cell cycle (CDK1, CDC6, CDC20), inflammation (IL-18, CCL2), and apoptosis (FAS). Interestingly, repetitive wounding resulted in prolonged misregulation of genes, including FAS, LRAT, and PEDF. The use of ECIS to induce wounding resulted in an over-representation of AMD-associated genes among those dysregulated genes, particularly genes associated with advanced AMD. This simple system provides a new model for further investigation of RPE cell wound response in AMD pathogenesis.

Proof of concept: could snake venoms be a potential source of bioactive compounds for control of mould growth and mycotoxin production.

The objective was to screen 10 snake venoms for their efficacy to control growth and mycotoxin production by important mycotoxigenic fungi including Aspergillus flavus, Aspergillus westerdijkiae, Penicillium verrucosum, Fusarium graminearum and F. langsethiae. The Bioscreen C rapid assay system was used. The venoms from the Viperidae snake family delayed growth of some of the test fungi, especially F. graminearum and F. langsethiae and sometimes A. flavus. Some were also able to reduce mycotoxin production. The two most potent crude snake venoms (Naja nigricollis and N. siamensis; 41 and 43 fractions, respectively) were further fractionated and 83/84 of these fractions were able to reduce mycotoxin production by >90% in two of the mycotoxigenic fungi examined. This study suggests that there may be significant potential for the identification of novel fungistatic/fungicidal bioactive compounds as preservatives of raw and processed food commodities post-harvest from such snake venoms.

Mantle cell lymphoma with involvement of the digestive tract. / Linfoma del manto con afección del tubo digestivo.

INTRODUCTION AND AIM: Mantle cell lymphoma is an aggressive subtype of B-cell non-Hodgkin lymphoma and its incidence is 0.5/100,000 inhabitants. Gastrointestinal involvement at diagnosis is 15-30%. The aim of our study was to analyze the clinical and endoscopic characteristics of mantle cell lymphoma affecting the digestive tract. MATERIAL AND METHODS: A retrospective study was conducted, based on a case series of patients with mantle cell lymphoma affecting the gastrointestinal tract that were diagnosed over a 10-year period. RESULTS: Ten patients (11.7%) had gastrointestinal tract involvement. The upper endoscopic findings were polypoid lesions (66%), thickened folds (44%), and nonspecific changes in the mucosa (33%). At colonoscopy, polypoid lesions were viewed in 100% of the patients and ulcerated lesions in 40%. CONCLUSION: Polypoid lesions are the most common endoscopic characteristics in patients with mantle cell lymphoma of the gastrointestinal tract. Upper endoscopy and colonoscopy should be carried out on patients with mantle cell lymphoma, even those with nonspecific symptoms, to check their gastrointestinal status. Gastrointestinal involvement has an impact on disease staging.

Expression of ABCA4 in the retinal pigment epithelium and its implications for Stargardt macular degeneration.

Recessive Stargardt disease (STGD1) is an inherited blinding disorder caused by mutations in the Abca4 gene. ABCA4 is a flippase in photoreceptor outer segments (OS) that translocates retinaldehyde conjugated to phosphatidylethanolamine across OS disc membranes. Loss of ABCA4 in Abca4-/- mice and STGD1 patients causes buildup of lipofuscin in the retinal pigment epithelium (RPE) and degeneration of photoreceptors, leading to blindness. No effective treatment currently exists for STGD1. Here we show by several approaches that ABCA4 is additionally expressed in RPE cells. (i) By in situ hybridization analysis and by RNA-sequencing analysis, we show the Abca4 mRNA is expressed in human and mouse RPE cells. (ii) By quantitative immunoblotting, we show that the level of ABCA4 protein in homogenates of wild-type mouse RPE is about 1% of the level in neural retina homogenates. (iii) ABCA4 immunofluorescence is present in RPE cells of wild-type and Mertk-/- but not Abca4-/- mouse retina sections, where it colocalizes with endolysosomal proteins. To elucidate the role of ABCA4 in RPE cells, we generated a line of genetically modified mice that express ABCA4 in RPE cells but not in photoreceptors. Mice from this line on the Abca4-/- background showed partial rescue of photoreceptor degeneration and decreased lipofuscin accumulation compared with nontransgenic Abca4-/- mice. We propose that ABCA4 functions to recycle retinaldehyde released during proteolysis of rhodopsin in RPE endolysosomes following daily phagocytosis of distal photoreceptor OS. ABCA4 deficiency in the RPE may play a role in the pathogenesis of STGD1.

Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference? / Prótesis totalmente cubiertas versus parcialmente cubiertas para el tratamiento paliativo del cáncer de esófago: ¿hay alguna diferencia?

INTRODUCTION AND AIMS: Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. MATERIALS AND METHODS: A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA®), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex®). RESULTS: Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). CONCLUSION: There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications.

Restoration of Mesenchymal RPE by Transcription Factor-Mediated Reprogramming.

Purpose: Transforming growth factor ß-mediated epithelial-to-mesenchymal transition (EMT) is a major component of the wound healing response and a negative determinant of retinal pigment epithelium (RPE) differentiation. We have shown previously that inhibition of TGFß signaling restored the capacity of mesenchymal RPE to differentiate; however, the potential lessens with extensive passaging. We investigated TGFß-independent mechanisms that regulate RPE differentiation following repetitive passaging. Methods: Retinal pigment epithelium-EMT was induced by repetitive passaging of fetal RPE at subconfluence. Suppression of EMT was achieved by the addition of A-83-01, a TGFß receptor kinase inhibitor. Transcriptomic analysis was used to identify potential TGFß independent processes that prevent differentiation after extensive passage. Downregulated transcription factors were identified and transduced into highly passaged RPE to restore cell differentiation. Restoration was evaluated according to morphology, expression of RPE/mesenchymal markers, transcriptomic analysis, cell doubling time, and senescence-associated ß-galactosidase (SA-ß-gal) activity. Results: A-83-01-treated RPE failed to differentiate after 7 passages (P7). This failure was concomitant with downregulation of RPE genes, misregulation of cell cycle genes, a decline in proliferative potential, and cell senescence. Exogenous expression of MYCN and OTX2 in conjunction with A-83-01 restored P7-RPE differentiation to a status similar to minimally passaged RPE. Moreover, the treatment allowed cells to maintain their differentiation capacity after extended passaging. Conclusions: Retinal pigment epithelium subjected to chronic wound stimulus undergoes TGFß-mediated EMT, loss of expression of signature RPE genes, and senescence. Targeting these aspects with a TGFß receptor kinase inhibitor, a RPE transcription factor, and a cell cycle regulator restores the capacity of highly passaged RPE cells to regenerate and differentiate.

Restoration of mesenchymal retinal pigmented epithelial cells by TGFß pathway inhibitors: implications for age-related macular degeneration.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of blindness. Most vision loss occurs following the transition from a disease of deposit formation and inflammation to a disease of neovascular fibrosis and/or cell death. Here, we investigate how repeated wound stimulus leads to seminal changes in gene expression and the onset of a perpetual state of stimulus-independent wound response in retinal pigmented epithelial (RPE) cells, a cell-type central to the etiology of AMD. METHODS: Transcriptome wide expression profiles of human fetal RPE cell cultures as a function of passage and time post-plating were determined using Agilent 44 K whole genome microarrays and RNA-Seq. Using a systems level analysis, differentially expressed genes and pathways of interest were identified and their role in the establishment of a persistent mesenchymal state was assessed using pharmacological-based experiments. RESULTS: Using a human fetal RPE cell culture model that considers monolayer disruption and subconfluent culture as a proxy for wound stimulus, we show that prolonged wound stimulus leads to terminal acquisition of a mesenchymal phenotype post-confluence and altered expression of more than 40 % of the transcriptome. In contrast, at subconfluence fewer than 5 % of expressed transcripts have two-fold or greater expression differences after repeated passage. Protein-protein and pathway interaction analysis of the genes with passage-dependent expression levels in subconfluent cultures reveals a 158-node interactome comprised of two interconnected modules with functions pertaining to wound response and cell division. Among the wound response genes are the TGFß pathway activators: TGFB1, TGFB2, INHBA, INHBB, GDF6, CTGF, and THBS1. Significantly, inhibition of TGFBR1/ACVR1B mediated signaling using receptor kinase inhibitors both forestalls and largely reverses the passage-dependent loss of epithelial potential; thus extending the effective lifespan by at least four passages. Moreover, a disproportionate number of RPE wound response genes have altered expression in neovascular and geographic AMD, including key members of the TGFß pathway. CONCLUSIONS: In RPE cells the switch to a persistent mesenchymal state following prolonged wound stimulus is driven by lasting activation of the TGFß pathway. Targeted inhibition of TGFß signaling may be an effective approach towards retarding AMD progression and producing RPE cells in quantity for research and cell-based therapies.

New compstatin peptides containing N-terminal extensions and non-natural amino acids exhibit potent complement inhibition and improved solubility characteristics.

Compstatin peptides are complement inhibitors that bind and inhibit cleavage of complement C3. Peptide binding is enhanced by hydrophobic interactions; however, poor solubility promotes aggregation in aqueous environments. We have designed new compstatin peptides derived from the W4A9 sequence (Ac-ICVWQDWGAHRCT-NH2, cyclized between C2 and C12), based on structural, computational, and experimental studies. Furthermore, we developed and utilized a computational framework for the design of peptides containing non-natural amino acids. These new compstatin peptides contain polar N-terminal extensions and non-natural amino acid substitutions at positions 4 and 9. Peptides with α-modified non-natural alanine analogs at position 9, as well as peptides containing only N-terminal polar extensions, exhibited similar activity compared to W4A9, as quantified via ELISA, hemolytic, and cell-based assays, and showed improved solubility, as measured by UV absorbance and reverse-phase HPLC experiments. Because of their potency and solubility, these peptides are promising candidates for therapeutic development in numerous complement-mediated diseases.

Array-based discovery of aptamer pairs.

Affinity reagent pairs that recognize distinct epitopes on a target protein can greatly improve the sensitivity and specificity of molecular detection. Importantly, such pairs can be conjugated to generate reagents that achieve two-site "bidentate" target recognition, with affinities greatly exceeding either monovalent component. DNA aptamers are especially well-suited for such constructs, because they can be linked via standard synthesis techniques without requiring chemical conjugation. Unfortunately, aptamer pairs are difficult to generate, primarily because conventional selection methods preferentially yield aptamers that recognize a dominant "hot spot" epitope. Our array-based discovery platform for multivalent aptamers (AD-MAP) overcomes this problem to achieve efficient discovery of aptamer pairs. We use microfluidic selection and high-throughput sequencing to obtain an enriched pool of aptamer sequences. Next, we synthesize a custom array based on these sequences, and perform parallel affinity measurements to identify the highest-affinity aptamer for the target protein. We use this aptamer to form complexes that block the primary binding site on the target, and then screen the same array with these complexes to identify aptamers that bind secondary epitopes. We used AD-MAP to discover DNA aptamer pairs that bind distinct sites on human angiopoietin-2 with high affinities, even in undiluted serum. To the best of our knowledge, this is the first work to discover new aptamer pairs using arrays. We subsequently conjugated these aptamers with a flexible linker to construct ultra-high-affinity bidentate reagents, with equilibrium dissociation constants as low as 97 pM: >200-fold better than either component aptamer. Functional studies confirm that both aptamers critically contribute to this ultrahigh affinity, highlighting the promise of such reagents for research and clinical use.

Spatial characterization of landscapes through multifractal analysis of DEM.

Landscape evolution is driven by abiotic, biotic, and anthropic factors. The interactions among these factors and their influence at different scales create a complex dynamic. Landscapes have been shown to exhibit numerous scaling laws, from Horton's laws to more sophisticated scaling of heights in topography and river network topology. This scaling and multiscaling analysis has the potential to characterise the landscape in terms of the statistical signature of the measure selected. The study zone is a matrix obtained from a digital elevation model (DEM) (map 10 × 10 m, and height 1 m) that corresponds to homogeneous region with respect to soil characteristics and climatology known as "Monte El Pardo" although the water level of a reservoir and the topography play a main role on its organization and evolution. We have investigated whether the multifractal analysis of a DEM shows common features that can be used to reveal the underlying patterns and information associated with the landscape of the DEM mapping and studied the influence of the water level of the reservoir on the applied analysis. The results show that the use of the multifractal approach with mean absolute gradient data is a useful tool for analysing the topography represented by the DEM.

ROCK Inhibition Extends Passage of Pluripotent Stem Cell-Derived Retinal Pigmented Epithelium.

Human embryonic stem cells (hESCs) offer a potentially unlimited supply of cells for emerging cell-based therapies. Unfortunately, the process of deriving distinct cell types can be time consuming and expensive. In the developed world, age-related macular degeneration (AMD) is the leading cause of blindness in the elderly, with more than 7.2 million people afflicted in the U.S. alone. Both hESC-derived retinal pigmented epithelium (hESC-RPE) and induced pluripotent stem cell-derived RPE (iPSC-RPE) are being developed for AMD therapies by multiple groups, but their potential for expansion in culture is limited. To attempt to overcome this passage limitation, we examined the involvement of Rho-associated, coiled-coil protein kinase (ROCK) in hESC-RPE and iPSC-RPE culture. We report that inhibiting ROCK1/2 with Y-27632 allows extended passage of hESC-RPE and iPSC-RPE. Microarray analysis suggests that ROCK inhibition could be suppressing an epithelial-to-mesenchymal transition through various pathways. These include inhibition of key ligands of the transforming growth factor-ß pathway (TGFB1 and GDF6) and Wnt signaling. Two important processes are affected, allowing for an increase in hESC-RPE expansion. First, ROCK inhibition promotes proliferation by inducing multiple components that are involved in cell cycle progression. Second, ROCK inhibition affects many pathways that could be converging to suppress RPE-to-mesenchymal transition. This allows hESC-RPE to remain functional for an extended but finite period in culture.

[The clinic of apathy in schizophrenia: a critical review of the issue]. / L'apathie dans la schizophrénie: une revue clinique et critique de la question.

INTRODUCTION: Today the concept of apathy is subject to many questions. This psychological state is present and predominant in different disorders such as neurodegenerative and psychiatric diseases or neurological acquired disorders. Apathy is a part of the clinical vocabulary, however, we can note that in the literature there remains confusion in its definition, and we can find an amalgam with other clinical symptoms. OBJECTIVES: The aim of this review is to provide a clarification of the concept of apathy in clinical practice in schizophrenia as well as to highlight the gaps that exist. LITERATURE FINDINGS: Apathy belongs to the negative symptoms of schizophrenia. For its understanding, it is necessary to define apathy as a multidimensional syndrome (cognitive, emotional, and behavioral) manifesting as a quantitative reduction of voluntary behaviors directed toward one or several goals. However, at present, we are witnessing a reductionist and simplistic conception of the syndrome of apathy and this especially in the Anglo-Saxon literature. Several authors reduce apathy to its behavioral component, so in other words, to avolition/amotivation. Avolition refers to a loss of self-initiated and spontaneous behaviors. In this definition only observable behavior is taken into account and not the underlying mechanisms (cognitive and emotional). In order to understand the syndrome of apathy, it is necessary to have a holistic and multidimensional outlook. Some authors have proposed diagnostic criteria for apathy by taking into account the different dimensions of apathy. Moreover not only is apathy confused with avolition, but it is also still difficult to distinguish it from depression. Apathy and depression share common clinical signs (i.e. loss of interest), but they also have distinct clinical signs (lack of motivation for apathy, and suicidal ideation for depression). Authors have shown that the presence of one symptom (apathy or depression) does not predict the presence of the other. An apathetic patient does not have to be necessarily in a depressive state and vice versa. However, to our knowledge, there is no data capable of distinguishing depression from apathy in schizophrenia, and knowing what is the part of one and the other when the patient has both symptoms. In addition, we can see that the confusion that persists between those two symptoms also stems from assessment tools. Indeed, some assessment tools such as the Montgomery and Asberg Depression Rating Scale (MARDS) have an apathy subscale. Therefore, this scale does not only evaluate depression. Regarding the assessment of apathy in schizophrenia, there are specific and nonspecific tools. Nonspecific tools define apathy differently. For this reason, authors have proposed to measure apathy by using analytic factors of negative symptoms. In this case, apathy is going to be assessed by the factor "motivation/pleasure" including anhedonia, asociality and avolition. This factor will provide the possibility of a better assessment of apathy. Concerning specific scales (like AES), there are gaps such as a lack of standardization in the execution and the quotation. Furthermore, no scale takes into account the factors causing apathy. CONCLUSION: Knowing the reasons for apathy is necessary because this syndrome is frequent in schizophrenia, and it is found in the different phases of this disease (prodromal, first episode psychosis, and chronic). In addition, apathy has significant functional consequences on the patient's quality of life, as well as on his or her global functioning. Indeed, apathy impacts on his or her social and professional life. Patients with schizophrenia have a loss of autonomy, less employment and social withdrawal. Consequently, interest in its drug or treatment it is obvious. However, drug and non-drug treatments are not specific to apathy and therefore little effective on this syndrome. Implications to stimulate future research are presented.

Intravenous thrombolysis in ischemic stroke with unknown onset using CT perfusion.

BACKGROUND: Acute ischemic stroke patients with unclear onset time presenting >4.5 h from last-seen-normal (LSN) time are considered late patients and excluded from i.v. thrombolysis. We aimed to evaluate whether this subgroup of patients is different from patients presenting >4.5 h from a witnessed onset, in terms of eligibility and response to computed tomography perfusion (CTP)-guided i.v. thrombolysis. METHODS: We prospectively studied consecutive acute non-lacunar middle cerebral artery (MCA) ischemic stroke patients presenting >4.5 h from LSN. All patients underwent multimodal CT and were considered eligible for i.v. thrombolysis according to CTP criteria. Two patient groups were established based on the knowledge of the stroke onset time. We compared the proportion of candidates suitable for intravenous thrombolysis between both groups, and their outcome after thrombolytic therapy. RESULTS: Among 147 MCA ischemic stroke patients presenting >4.5 h from LSN, stroke onset was witnessed in 74 and unknown in 73. Thirty-seven (50%) patients in the first group and 32 (44%) in the second met CTP criteria for thrombolysis (P = 0.7). Baseline variables were comparable between both groups with the exception of age, which was higher in the unclear onset group. The rates of early neurological improvement (54.1% vs 46.9%), 2-h MCA recanalization (43.5% vs 37%), symptomatic hemorrhagic transformation (3% vs 0%) and good 3-month functional outcome (62.2% vs 56.3%) did not differ significantly between both groups. CONCLUSION: Delayed stroke patients with unknown onset time were no different than patients >4.5 h regarding eligibility and response to CTP-based i.v. thrombolysis.

Measles virus C protein impairs production of defective copyback double-stranded viral RNA and activation of protein kinase R.

Measles virus (MV) lacking expression of C protein (C(KO)) is a potent activator of the double-stranded RNA (dsRNA)-dependent protein kinase (PKR), whereas the isogenic parental virus expressing C protein is not. Here, we demonstrate that significant amounts of dsRNA accumulate during C(KO) mutant infection but not following parental virus infection. dsRNA accumulated during late stages of infection and localized with virus replication sites containing N and P proteins. PKR autophosphorylation and stress granule formation correlated with the timing of dsRNA appearance. Phospho-PKR localized to dsRNA-containing structures as revealed by immunofluorescence. Production of dsRNA was sensitive to cycloheximide but resistant to actinomycin D, suggesting that dsRNA is a viral product. Quantitative PCR (qPCR) analyses revealed reduced viral RNA synthesis and a steepened transcription gradient in C(KO) virus-infected cells compared to those in parental virus-infected cells. The observed alterations were further reflected in lower viral protein expression levels and reduced C(KO) virus infectious yield. RNA deep sequencing confirmed the viral RNA expression profile differences seen by qPCR between C(KO) mutant and parental viruses. After one subsequent passage of the C(KO) virus, defective interfering RNA (DI-RNA) with a duplex structure was obtained that was not seen with the parental virus. We conclude that in the absence of C protein, the amount of PKR activator RNA, including DI-RNA, is increased, thereby triggering innate immune responses leading to impaired MV growth.

Effects of naltrexone on neural and subjective response to alcohol in treatment-seeking alcohol-dependent patients.

BACKGROUND: Positively reinforcing properties of alcohol are in part mediated by activation of the ventral striatum (VS). Alcohol-induced release of endogenous opioids is thought to contribute to this response. Preclinical studies show that the opioid antagonist naltrexone (NTX) can block this cascade, but its ability to do so in treatment-seeking alcoholics has not been examined. Our objective was to study the effects of NTX on alcohol-induced VS activation and on amygdala response to affective stimuli in treatment-seeking alcohol-dependent inpatients. METHODS: Sixty-three treatment-seeking alcoholics were randomized to receive NTX (50 mg) or placebo (PLC) daily. On Day 7, participants underwent an alcohol cue reactivity session, and craving was measured using the Penn Alcohol Craving Scale. On Day 9, participants received a saline infusion followed by an alcohol infusion and also viewed affective stimuli in a magnetic resonance scanner. RESULTS: Irrespective of medication treatment condition, the alcohol infusion did not activate the VS in the alcohol-dependent patients. Unexpectedly, VS activation was greater in NTX treated patients than in the PLC group. NTX treated patients also reported increased craving in response to alcohol cue exposure, and increased subjective response to alcohol ("high" and "intoxicated") compared to PLC subjects. No significant effects of alcohol infusion on brain response to affective stimuli were in the NTX or PLC groups. CONCLUSIONS: Unlike previous findings in social drinkers, a moderate level of intoxication did not activate the VS in treatment-seeking alcoholics. This is likely to reflect tolerance to the positively reinforcing properties of alcohol in this clinical population. Our findings may help explain the efficacy of NTX to reduce heavy drinking, but not to maintain abstinence.

Tumour necrosis factor-α plus interleukin-10 low producer phenotype predicts acute kidney injury and death in intensive care unit patients.

Genetic polymorphism studies of cytokines may provide an insight into the understanding of acute kidney injury (AKI) and death in intensive care unit (ICU) patients. The aim of this study was to investigate whether the genetic polymorphisms of -308 G < A tumour necrosis factor (TNF)-α, -174 G > C interleukin (IL)-6 and -1082 G > A IL-10 may predispose ICU patients to the development of AKI and/or death. In a prospective nested case-control study, 303 ICU patients and 244 healthy individuals were evaluated. The study group included ICU patients who developed AKI (n = 139) and 164 ICU patients without AKI. The GG genotype of TNF-α (low producer phenotype) was significantly lower in the with AKI than without AKI groups and healthy individuals (55 versus 62 versus 73%, respectively; P = 0·01). When genotypes were stratified into four categories of TNF-α/IL-10 combinations, it was observed that low TNF-α plus low IL-10 producer phenotypes were more prevalent in patients with AKI, renal replacement therapy and death (P < 0·05). In logistic regression analysis, low TNF-α producer plus low IL-10 producer phenotypes remained as independent risk factors for AKI and/or death [odds ratio (OR) = 2·37, 95% confidence interval (CI): 1·16-4·84; P = 0·02] and for renal replacement therapy (RRT) and/or death (OR = 3·82, 95% CI: 1·19-12·23; P = 0·02). In this study, the combination of low TNF-α plus low IL-10 producer phenotypes was an independent risk factor to AKI and/or death and RRT and/or death in critically ill patients. Our results should be validated in a larger prospective study with long-term follow-up to emphasize the combination of these genotypes as potential risk factors to AKI in critically ill patients.

[Evolution of the concept of apathy: the need for a multifactorial approach in schizophrenia]. / Évolution du concept d'apathie: nécessité d'une approche multifactorielle dans la schizophrénie.

BACKGROUND: Schizophrenia is a chronic and severe mental illness that affects over 1% of the population, characterized by multiple symptom dimensions. One of this class of symptoms, "negative symptoms", have received more attention over the last few years. Negative symptoms, including among others blunted affect, withdrawal or apathy, are particularly important for recovery and are associated with negative functional outcomes, such as inability to get an employment and conduct normal daily living activities. While positive symptoms are usually treated by antipsychotic drugs, negative symptoms are usually persistent, which indicates the need for better treatment. The aim of this article is to highlight recent scientific progress on apathy and to explore current multidimensional approaches of this concept in schizophrenia. Apathy is a symptom frequently encountered in schizophrenia and in many neurological disorders. Therefore, it can be regarded as a transnosographic symptom. LITERATURE FINDINGS: A long time considered as a loss of motivation (psychological concept hard to define), recent descriptive and etiological models have proposed to consider apathy as a multidimensional phenomenon. Marin et al., have proposed a model of apathy in reference to the motivation concept. Marin et al.'s apathy model is composed of three dimensions: firstly, cognitive dimension, secondly, sensory-motor dimension and thirdly, affective dimension. These authors propose to differentiate "apathy syndrome" from "apathy symptom". "Apathy syndrome" resulting from a lack of motivation whereas "apathy symptom" results from cognitive and/or emotional/affective disorders. In addition, Marin et al. propose that apathy syndrome corresponds to the "lack of motivation" not attributable to diminished level of consciousness, cognitive impairment or emotional distress. Following this proposal, Levy and Dubois propose to define apathy as a quantitative reduction of self-generated, voluntary and purposeful behaviors. It is therefore observable and can be quantified. Levy and Dubois have proposed an apathy model considering: firstly, apathy as a syndrome related to reduction in goal-directed behaviors; secondly, anatomically, apathy can be secondary to dysfunctions or lesions of the prefrontal cortex. Since the prefrontal cortex is functionally and anatomically heterogeneous, subtypes of apathy occur in diseases affecting the basal ganglia, because these diseases disrupt associative and limbic pathways from/to the prefrontal cortex; thirdly, from a pathophysiological point of view, apathy may be explained by the impact of lesions or dysfunctions of the basal ganglia, because these lesions or dysfunctions lead to a loss of temporal and spatial focalization, both of which result in a diminished extraction of the relevant signal within the frontal cortex, thereby inhibiting the capacity of the frontal cortex to select, initiate, maintain and shift programs of action.