Search

Abstract Background Mental health in the older adults represents a public health issue, especially depression and suicide, and even more in the Brittany French region. Community Mental Health Centers (CMHC) are the front-line French psychiatric healthcare organizations, but the number, characteristics and trajectories of the older adults consulting there for the first time are unknown. Method An exhaustive cross-sectional study from medical records about first-time consultants in any CMHC of the Guillaume Régnier Hospital Center in 2019, and quantifying and describing the 65 and over ones according to socio-demographic, clinical, geographic and trajectory criteria. Results This population represents 9.7% of all first consulting in CMHCs. We can note that 70.5% are female, 46.8% are living alone and 31.2% are widowed. These 3 rates are higher than in the general population. The main diagnosis we found is mood disorder (35.1%). Organic mental disorders are scarce (8.2%). Most people are referred by a general practitioner (53.4%) or a specialist/hospital center (23.7%). The main referral at the end is to CMHC care (73.6%). Only 20.0% had a referral to non-psychiatric health professionals (GP, coordination support teams, geriatrics, other professionals). Significant differences in the referral at the end exist between 65 and 74, who are more referred to CMHC professionals, and 75 and over, who are more frequently referred to non-psychiatric health professionals. Significant discrepancies about who referred are found according to community area-type. Conclusion These results align with the literature about known health-related characteristics and the importance of depression in the older people. They question the link with non-psychiatric professionals, and the need to structure a homogeneous care organization in psychiatric care for the older adults with trained professionals, especially for the 75 and over.

Abstract Late-life depression (LLD) is both common and disabling and doubles the risk of dementia onset. Apathy might constitute an additional risk of cognitive decline but clear understanding of its pathophysiology is lacking. While white matter (WM) alterations have been assessed using diffusion tensor imaging (DTI), this model cannot accurately represent WM microstructure. We hypothesized that a more complex multi-compartment model would provide new biomarkers of LLD and apathy. Fifty-six individuals (LLD n = 35, 26 females, 75.2 ± 6.4 years, apathy evaluation scale scores (41.8 ± 8.7) and Healthy controls, n = 21, 16 females, 74.7 ± 5.2 years) were included. In this article, a tract-based approach was conducted to investigate novel diffusion model biomarkers of LLD and apathy by interpolating microstructural metrics directly along the fiber bundle. We performed multivariate statistical analysis, combined with principal component analysis for dimensional data reduction. We then tested the utility of our framework by demonstrating classically reported from the literature modifications in LDD while reporting new results of biological-basis of apathy in LLD. Finally, we aimed to investigate the relationship between apathy and microstructure in different fiber bundles. Our study suggests that new fiber bundles, such as the striato-premotor tracts, may be involved in LLD and apathy, which bring new light of apathy mechanisms in major depression. We also identified statistical changes in diffusion MRI metrics in 5 different tracts, previously reported in major cognitive disorders dementia, suggesting that these alterations among these tracts are both involved in motivation and cognition and might explain how apathy is a prodromal phase of degenerative disorders.

Vitamin C (ascorbate; Asc) is a biologically important antioxidant that scavenges reactive oxygen species such as deleterious alkylperoxyl radicals (ROO•), which are generated by radical-mediated oxidation of biomolecules in the presence of oxygen. The radical trapping proprieties of Asc are conventionally attributed to its ability to undergo single-electron transfers with reactive species. According to this mechanism, the reaction between Asc and ROO• results in the formation of dehydroascorbate (DHA) and the corresponding hydroperoxides (ROOH). When studying the reactivity of DNA 5-(2′-deoxyuridinyl)methylperoxyl radicals, we discovered a novel pathway of ROO• scavenging by Asc. The purpose of this study is to elucidate the underlying mechanism of this reaction with emphasis on the characterization of intermediate and final decomposition products. We show that the trapping of ROO• by Asc leads to the formation of an alcohol (ROH) together with an unstable cyclic oxalyl-l-threonate intermediate (cOxa-Thr), which readily undergoes hydrolysis into a series of open-chain oxalyl-l-threonic acid regioisomers. The structure of products was determined by detailed MS and NMR analyses. The above transformation can be explained by initial peroxyl radical addition (PRA) onto the C2=C3 enediol portion of Asc. Following oxidation of the resulting adduct radical, the product subsequently undergoes Baeyer-Villiger rearrangement, which releases ROH and generates the ring expansion product cOxa-Thr. The present investigation provides robust clarifications of the peroxide-mediated oxidation chemistry of Asc and DHA that has largely been obscured in the past by interference with autooxidation reactions and difficulties in analyzing and characterizing oxidation products. Scavenging of ROO• by PRA onto Asc may have beneficial consequences since it directly converts ROO• into ROH, which prevents the formation of potentially deleterious ROOH, although it induces the breakdown of Asc into fragments of oxalyl-l-threonic acid.

Introduction: The use of teleconsultations for mental health has drastically increased since 2020 due to the Covid19 pandemic. In the present paper, we aimed to analyze the advantages and disadvantages of teleconsultations for mental health compared to face-to-face consultations, and to provide recommendations in this domain. Methods: The recommendations were gathered using a Delphi methodology. The expert panel (N = 21) included professionals from the health and ICT domains. They answered questions via two rounds of web surveys, and then discussed the results in a plenary meeting. Some of the questions were also shared with non-experts (N = 104). Results: Both the experts and the non-experts with teleconsultation experience reported a general satisfaction concerning teleconsultations. A SWOT analysis revealed several strengths and opportunities of teleconsultations for mental health, but also several weaknesses and threats. The experts provided a set of practical recommendations for the preparation and organization of teleconsultations for mental health. Discussion: Teleconsultations for mental health have the potential to allow access to care for patients in remote and isolated areas. Thus, their use will unlikely be discontinued after the end of the pandemic. In this context, we suggest that the collaboration among clinicians, researchers, and interface designers is crucial to improve usability and user experience for both clinicians and patients. The importance of teaching teleconsultation skills and informing the public on the features of teleconsultations (e.g., data privacy/security) is also highlighted.

Abstract While there is substantial evidence that cannabis use is associated with differences in human brain development, most of this evidence is correlational in nature. Bayesian causal network (BCN) modeling attempts to identify probable causal relationships in correlational data using conditional probabilities to estimate directional associations between a set of interrelated variables. In this study, we employed BCN modeling in 637 adolescents from the IMAGEN study who were cannabis naïve at age 14 to provide evidence that the accelerated prefrontal cortical thinning found previously in adolescent cannabis users by Albaugh et al. [1] is a result of cannabis use causally affecting neurodevelopment. BCNs incorporated data on cannabis use, prefrontal cortical thickness, and other factors related to both brain development and cannabis use, including demographics, psychopathology, childhood adversity, and other substance use. All BCN algorithms strongly suggested a directional relationship from adolescent cannabis use to accelerated cortical thinning. While BCN modeling alone does not prove a causal relationship, these results are consistent with a body of animal and human research suggesting that adolescent cannabis use adversely affects brain development.

Abstract Background Duloxetine is an antidepressant that benefits from a wide range of approval in the elderly population, while its safety for use compared to non-elderly is not clearly assessed. This protocol outlines a systematic review and individual participant data meta-analysis comparing the tolerability of duloxetine between elderly and non-elderly. Methods Searches will be conducted in PubMed, ClinicalTrials.gov , Clinicaltrialsregister.eu, data sharing platforms, FDA drug approval packages, European public assessment reports and withdrawn applications from the EMA website. The review will be performed on studies available in electronic databases from their date of inception to the 31 March 2022. Only randomized controlled clinical trials, comparing duloxetine to placebo, will be included in this meta-analysis. The studies will be selected if they comprise both elderly and non-elderly adults, in conditions of use of duloxetine approved by the European Medical Agency (EMA) and the Food and Drug Administration (FDA). The primary outcome will be the rate ratio of serious adverse events under duloxetine compared to placebo, between participants at least 65 years old and non-elderly. Second, the number of any adverse events, clinical efficacy and quality of life will be compared between elderly and non-elderly under both interventions. The quality of evidence in the tolerability of duloxetine will be assessed using the GRADE system. A one or two-stage individual participant data random effect meta-analysis will be conducted depending on the availability of the data. Discussion This meta-analysis will investigate the tolerability safety of duloxetine in the elderly population across all conditions approved by European and American regulatory authorities. The results from this meta-analysis are intended to help prescribers to provide better care for the elderly population. Systematic review registration The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO; registration number: CRD42019130488 ).

Abstract Emerging evidence showed that major depressive disorder (MDD) is associated with disruptions of brain structural and functional networks, rather than impairment of isolated brain region. Thus, connectome-based models capable of predicting the depression severity at the individual level can be clinically useful. Here, we applied a machine-learning approach to predict the severity of depression using resting-state networks derived from source-reconstructed Electroencephalography (EEG) signals. Using regression models and three independent EEG datasets (N = 328), we tested whether resting state functional connectivity could predict individual depression score. On the first dataset, results showed that individuals scores could be reasonably predicted (r = 0.6, p = 4 × 10–18) using intrinsic functional connectivity in the EEG alpha band (8–13 Hz). In particular, the brain regions which contributed the most to the predictive network belong to the default mode network. We further tested the predictive potential of the established model by conducting two external validations on (N1 = 53, N2 = 154). Results showed statistically significant correlations between the predicted and the measured depression scale scores (r1 = 0.52, r2 = 0.44, p

The current literature review aimed to evaluate the effectiveness of rTMS on the precuneus as a potential treatment for Alzheimer’s disease (AD). Although the number of studies specifically targeting the precuneus is limited, the results from this review suggest the potential benefits of this approach. Future studies should focus on exploring the long-term effects of rTMS on the precuneus in Alzheimer’s disease patients, as well as determining the optimal stimulation parameters and protocols for this population. Additionally, investigating the effects of rTMS on the precuneus in combination with other brain regions implicated in AD may provide valuable insights into the development of effective treatment for this debilitating neurodegenerative disorder.

Background: Bipolar disorder (BP) and schizophrenia (SZ) are both psychiatric conditions characterized by deficits in cognitive control (executive function and attention) and emotion regulation. The emotional Stroop task makes it possible to measure such deficits and to study the impact of emotions on cognitive control. The objective of the present study was thus to explore this impact in people with BP or SZ. Methods: Participants were 21 individuals with BP, 23 participants with SZ, and 42 control participants (HC). Results: Participants with SZ had greater cognitive impairments than participants with BP, who had greater cognitive impairments than HC. The BP group had longer reaction times than the HC group for the negative valence, and the SZ group had longer reaction times than the HC group for all three valences (i.e., positive, negative, and neutral). We did not observe an effect of emotional valence within any of the three groups. Conclusions: The SZ and BP groups had difficulty inhibiting irrelevant emotional stimuli during a cognitive task, reflecting deficits in the engagement of cognitive control during emotion regulation in both pathologies.

Personality and subjective well-being (SWB) have been suggested to be strongly related in previous studies. This study was intended to confirm the relationship between personality and SWB and tried to seek out the genetic variants which underlie both personality and SWB. The subjects were 890 participants from Chinese Han population. We evaluated their personality using the Big Five Inventory (BFI) and used the Satisfaction With Life Scale (SWLS) to reflect their SWB. Five single nucleotide polymorphisms (SNPs) were selected from the literature (rs1426371, rs2164273, rs322931, rs3756290, rs490647) and genotyped for genetic association study. We found negative correlations between neuroticism and SWB. On the contrary, extraversion and agreeableness were positively associated with SWB. Three SNPs (rs2164273, rs3756290, rs490647) out of the five were found to connect with personality (extraversion, neuroticism, conscientiousness and openness to experience) and rs490647 variants of GRIK3 was also associated with SWB. Individuals carrying G allele at this site were predisposed to have lower risk to be neuroticism and greater chance to be extraverted, open and satisfied with their life. In summary, our study revealed that rs490647 might be a good candidate genetic variant for personality and SWB in Chinese Han population.

Background Myocardial injury is associated with higher mortality after transcatheter aortic valve replacement (TAVR) and might be increased by prior balloon aortic valvuloplasty (BAV). We aimed to evaluate the impact of prior BAV versus direct prosthesis implantation on myocardial injury occurring after (TAVR) with balloon‐expandable prostheses. Methods and Results The DIRECTAVI (Direct Transcatheter Aortic Valve Implantation) trial, an open‐label randomized study, demonstrated noninferiority of TAVR without BAV (direct TAVR group) compared with systematic BAV (BAV group) with the Edwards SAPIEN 3 valve. High‐sensitivity troponin was assessed before and the day after the procedure. Incidence of myocardial injury after the procedure (high‐sensitivity troponin elevation >15× the upper reference limit [14 ng/L]) was the main end point. Impact of myocardial injury on 1‐month adverse events (all‐cause mortality, stroke, major bleeding, major vascular complications, transfusion, acute kidney injury, heart failure, pacemaker implantation, and aortic regurgitation) was evaluated. Preprocedure and postprocedure high‐sensitivity troponin levels were available in 211 patients. The mean age of patients was 83 years (78–87 years), with 129 men (61.1%). Mean postprocedure high‐sensitivity troponin was 124.9±81.4 ng/L in the direct TAVR group versus 170.4±127.7 ng/L in the BAV group (P=0.007). Myocardial injury occurred in 42 patients (19.9%), including 13 patients (12.2%) in the direct TAVR group and 29 (27.9%) in the BAV group (P=0.004). BAV increased by 2.8‐fold (95% CI, 1.4–5.8) myocardial injury probability. Myocardial injury was associated with 1‐month adverse events (P=0.03). Conclusions BAV increased the incidence and magnitude of myocardial injury after TAVR with new‐generation balloon‐expandable valves. Myocardial injury was associated with 1‐month adverse events. These results argue in favor of direct SAPIEN 3 valve implantation. Registration URL: https://www.Clinicaltrials.gov; Unique identifier: NCT02729519.

Abstract This paper introduces a “blue pyjama syndrome” (whereby wearing hospital pyjamas results in an exaggerated impression of severity). We performed a 5-day, prospective, randomized, cross-over study in a French mood disorder unit for inpatients. At Day 1 (D1) and Day 5 (D5), two 5-minute video interviews were recorded with patients in pyjamas or in day clothes (the sequence was randomly allocated). Psychiatrists unaware of the study objective assessed the videos and scored their clinical global impressions (CGI, with scores ranging from 1 to 7). Of 30 participants with major depressive episode selected for inclusion, 26 participants (69% women) provided useable data for an evaluation by 10 psychiatrists. Pyjamas significantly increased the psychiatrists’ CGI ratings of disease severity by 0·65 [0·27; 1·02] points. The psychiatrists’ global impressions also rated patients as significantly less severe at D5 in comparison with D1 by −0·66 [−1·03; −0·29] points. The “blue pyjama syndrome” is in the same order of magnitude as the difference observed after a week of hospitalisation. This potentially calls into question the reliability and validity of observer ratings of depression.

Mood depressive disorder is one of the most disabling chronic diseases with a high rate of everyday life disability that affects 350 million people around the world. Recent advances in neuroimaging have reported widespread structural abnormalities, suggesting a dysfunctional frontal-limbic circuit involved in the pathophysiological mechanisms of depression. However, a variety of different white matter regions has been implicated and is sought to suffer from lack of reproducibility of such categorical-based biomarkers. These inconsistent results might be attributed to various factors: actual categorical definition of depression as well as clinical phenotype variability. In this study, we 1/ examined WM changes in a large cohort (114 patients) compared to a healthy control group and 2/ sought to identify specific WM alterations in relation to specific depressive phenotypes such as anhedonia (i.e. lack of pleasure), anxiety and psychomotor retardation –three core symptoms involved in depression. Consistent with previous studies, reduced white matter was observed in the genu of the corpus callosum extending to the inferior fasciculus and posterior thalamic radiation, confirming a frontal-limbic circuit abnormality. Our analysis also reported other patterns of increased fractional anisotropy and axial diffusivity as well as decreased apparent diffusion coefficient and radial diffusivity in the splenium of the corpus callosum and posterior limb of the internal capsule. Moreover, a positive correlation between FA and anhedonia was found in the superior longitudinal fasciculus as well as a negative correlation in the cingulum. Then, the analysis of the anxiety and diffusion metric revealed that increased anxiety was associated with greater FA values in genu and splenium of corpus callosum, anterior corona radiata and posterior thalamic radiation. Finally, the motor retardation analysis showed a correlation between increased Widlöcher depressive retardation scale scores and reduced FA in the body and genu of the corpus callosum, fornix, and superior striatum. Through this twofold approach (categorical and phenotypic), this study has underlined the need to move forward to a symptom-based research area of biomarkers, which help to understand the pathophysiology of mood depressive disorders and to stratify precise phenotypes of depression with targeted therapeutic strategies. Keywords: Diffusion-weighted imaging, Voxel-based analysis, Fractional anisotropy value, Depression, Categorical and phenotypic approach

Several studies have investigated the age-related impact in cognitive action control. However, to our knowledge, none has focused on the effect of moderate age on the strength of automatic activation according to the activation suppression model. We therefore investigated the effect of moderate age on cognitive action control using an oculomotor version of the Simon task and distributional analyses.A group of middle-aged (n = 39; 57 ± 9 years) healthy adults was compared to a group of young healthy participants (n = 43; 24 ± 3 years). We first analyzed the overall impact of age on the congruence effect and then used conditional accuracy functions and delta plots to assess the strength of automatic activation and selective inhibition respectively.Compared to young participants, middle-aged participants showed a greater congruence effect as well as higher rates of fast errors in conflict situations indicating an enhanced impulsive action selection. Furthermore, the overall downward slope of the congruence effect’s evolution was significantly steeper in older participants and the last slope tended to be significantly steeper. This may indicate that the middle-aged participants exerted a stronger selective inhibition.Our results suggest that middle-aged adults are more prone to impulsive action selection than young adults. Recent theories postulate that older adults might implement compensatory mechanisms to supply cognitive difficulties. This is in line with our results suggesting a potential greater selective inhibition. Overall, this study proposes that moderate aging impacts both processes of impulsive response selection and suppression underlying cognitive action control.

The mechanisms behind weight gain following deep brain stimulation (DBS) surgery seem to be multifactorial and suspected depending on the target, either the subthalamic nucleus (STN) or the globus pallidus internus (GPi). Decreased energy expenditure following motor improvement and behavioral and/or metabolic changes are possible explanations. Focusing on GPi target, our objective was to analyze correlations between changes in brain metabolism (measured with PET) and weight gain following GPi-DBS in patients with Parkinson's disease (PD). Body mass index was calculated and brain activity prospectively measured using 2-deoxy-2[18F]fluoro-D-glucose PET four months before and four months after the start of GPi-DBS in 19 PD patients. Dopaminergic medication was included in the analysis to control for its possible influence on brain metabolism. Body mass index increased significantly by 0.66 ± 1.3 kg/m2 (p = 0.040). There were correlations between weight gain and changes in brain metabolism in premotor areas, including the left and right superior gyri (Brodmann area, BA 6), left superior gyrus (BA 8), the dorsolateral prefrontal cortex (right middle gyrus, BAs 9 and 46), and the left and right somatosensory association cortices (BA 7). However, we found no correlation between weight gain and metabolic changes in limbic and associative areas. Additionally, there was a trend toward a correlation between reduced dyskinesia and weight gain (r = 0.428, p = 0.067). These findings suggest that, unlike STN-DBS, motor improvement is the major contributing factor for weight gain following GPi-DBS PD, confirming the motor selectivity of this target.

The mammalian retina contains approximately 30 neuropeptides that are synthetized by different neuronal cell populations, glia, and the pigmented epithelium. The presence of these neuropeptides leaves a mark on normal retinal molecular processes and physiology, and they are also crucial in fighting various pathologies (e.g., diabetic retinopathy, ischemia, age-related pathologies, glaucoma) because of their protective abilities. Retinal pathologies of different origin (metabolic, genetic) are extensively investigated by genetically manipulated in vivo mouse models that help us gain a better understanding of the molecular background of these pathomechanisms. These models offer opportunities to manipulate gene expression in different cell types to help reveal their roles in the preservation of retinal health or identify malfunction during diseases. In order to assess the current status of transgenic technologies available, we have conducted a literature survey focused on retinal disorders of metabolic origin, zooming in on the role of retinal neuropeptides in diabetic retinopathy and ischemia. First, we identified those neuropeptides that are most relevant to retinal pathologies in humans and the two clinically most relevant models, mice and rats. Then we continued our analysis with metabolic disorders, examining neuropeptide-related pathways leading to systemic or cellular damage and rescue. Last but not least, we reviewed the available literature on genetically modified mouse strains to understand how the manipulation of a single element of any given pathway (e.g., signal molecules, receptors, intracellular signaling pathways) could lead either to the worsening of disease conditions or, more frequently, to substantial improvements in retinal health. Most attention was given to studies which reported successful intervention against specific disorders. For these experiments, a detailed evaluation will be given and the possible role of converging intracellular pathways will be discussed. Using these converging intracellular pathways, curative effects of peptides could potentially be utilized in fighting metabolic retinal disorders. [ABSTRACT FROM AUTHOR]

Byline: Robert Gabriel, Johannes Kreissig This paper gives an overview of existing Life Cycle Assessment (LCA) studies of drinking water installations in Europe. The characteristics and results of the two most widely known and used studies, the VENOB study and the CREM study, are described in detail. Readers get a thorough understanding of the key issues and parameters of life cycle studies in this field. As the study results diverge significantly, the authors analyse the reasons for this discrepancy, classifying them into the categories 'goal and scope', 'methodology', 'data' and 'review'. This case study analysis may be of potential interest to those who deal with comparative LCA studies.

A Laboratory study was carried out to assess the toxic effects of aqueous extracts of Piptadeniastrium africanum bark on Clarias gariepinus juveniles using the static bioassay with continuous aeration method. Phytochemical analysis of the P. africanum aqueous bark extract revealed the presence of tannins (1.95 %), saponin (2.95 %), flavonoid (5.63 %), Glycosides (1.05 %), Steroid (2.35 %), Terpens, (2.70 %).0 (control), 25, 50, 75, 100, 125 mg/L concentrations were then applied to Clarias gariepinus juveniles (Mean weight: 18.26± 0.04 g) to determine the acute toxicity. The result obtained revealed the 96 h LC50 values to be 42.21 mg/L with 95 % confidence limit of 30.37-58.67 mg/L. Fish exposed to acute toxicity test exhibited behavioural changes such as discolouration, air gulping, erratic swimming, aggression, excessive mucus secretion, and settling at the bottom motionless just before death. Histological assessment of the gills showed that acute exposure of P. africanum bark led to degeneration of primary and secondary lamellae, lamellae with marginal channel dilation, blanketing of the lamellae, hyperplasia of epithelial cells, epithelial lifting and haemorrhage, oedema, necrosis and malformed secondary lamellae of the African catfish. The liver also showed focal necrosis, bile stagnation, nuclear degeneration, hepatocytes with irregular shaped nucleaus, cytoplasmic vacuolation, vascular congestion, bile pigment disintegration and cytoplasic degeneration Hyperplasia of epithelial cells and fusion of secondary lamellae. The toxic effect of the aqueous extract of the plant on C. gariepinus juveniles was both time and dose dependent. [ABSTRACT FROM AUTHOR]

A study was conducted to assess fish species abundance and diversity of River Uke, Uke, Nasarawa State, Nigeria. Fish were sampled from three sites, upper (A), middle (B) and lower (C) courses of the river. The study lasted for ten months from June 2014 to March 2015. A total of two thousand, one hundred and twenty six (2,126) fish comprising of 7 families and 11 species were sampled. Seasonal fish abundance of River Uke revealed that average monthly catch in the wet season was 25 % lower than in the dry season. Cichlidae dominated the sampled fish families accounting for 26.20 % of total catch while Latidae was least abundant with 6.21 %. Monthly fish abundance was dominated by three species, namely, Clarias gariepinus (18.44 %), Tilapia zilli (14.44 %) and Oreochromis niloticus (11.76 %) all accounting for 44.64% of the total catch. The trend of monthly fish abundance also showed a bi-modal peak with the minor peak observed in March (260) and the major peak in November (292). Fish abundance by sites revealed individual catches of 671, 365 and 1090 in Site A, B and C, respectively. Total Shannon-Wiener Diversity index of River Uke in this study was 2.312 and the index values were generally higher in the wet season (except October) than in the dry season. Total Simpson Index calculated for River Uke in this study was 0.892. [ABSTRACT FROM AUTHOR]

Copyright of Revue Valaque d'Etudes Economiques is the property of Valahia University of Targoviste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The retina is sensitive to age-dependent degeneration. To find suitable animal models to understand and map this process has particular importance. The degu (Octodon degus) is a diurnal rodent with dichromatic color vision. Its retinal structure is similar to that in humans in many respects, therefore, it is well suited to study retinal aging. Histological, cell type-specific and ultrastructural alterations were examined in 6-, 12- and 36-months old degus. The characteristic layers of the retina were present at all ages, but slightly loosened tissue structure could be observed in 36-month-old animals both at light and electron microscopic levels. Elevated Glial fibrillary acidic protein (GFAP) expression was observed in Müller glial cells in aging retinas. The number of rod bipolar cells and the ganglion cells was reduced in the aging specimens, while that of cone bipolar cells remained unchanged. Other age-related differences were detected at ultrastructural level: alteration of the retinal pigment epithelium and degenerated photoreceptor cells were evident. Ribbon synapses were sparse and often differed in morphology from those in the young animals. These results support our hypothesis that (i) the rod pathway seems to be more sensitive than the cone pathway to age-related cell loss; (ii) structural changes in the basement membrane of pigment epithelial cells can be one of the early signs of degenerative processes; (iii) the loss of synaptic proteins especially from those of the ribbon synapses are characteristic; and (iv) the degu retina may be a suitable model for studying retinal aging. [ABSTRACT FROM AUTHOR]

Communication offers indefinite possibilities in the social life, including the organizational one, playing a huge role in human existence. The idea of communication as essential element and means of individual life is widely accepted in all fields "Social organization is impossible without communication" (Miller, 1954, p. 337). Communication is rapidly included among an organization's fundamental functions, together with other ones (organizational, leadership, decision etc.). Organizations have begun to be more and more interested in their image towards the public, customers, suppliers, shoppers etc. Also, each manager, regardless of his hierarchic level, has begun to care about his image in the eyes of his superiors, equals and subordinates. It was noted at one point that what is called image-capital is more important than the economic, financial capital. Organizational communication has become so important that the authors that address in their work its general issue start to relate more strongly to it. [ABSTRACT FROM AUTHOR]

Exposure to an enriched environment has been shown to have many positive effects on brain structure and function. Numerous studies have proven that enriched environment can reduce the lesion induced by toxic and traumatic injuries. Impoverished environment, on the other hand, can have deleterious effects on the outcome of neuronal injuries. We have previously shown that enriched conditions have protective effects in retinal injury in newborn rats. It is well-known that the efficacy of neuroprotective strategies can depend on age and gender. The aim of the present study, therefore, was to examine the effects of environmental enrichment and social isolation in retinal ischemia. We used bilateral common carotid artery occlusion to induce retinal hypoperfusion in adult Wistar rats of both genders. Groups were housed in standard, enriched or impoverished conditions. Impoverished environment was induced by social isolation. Retinas were processed for histological analysis after two weeks of survival. In the present study, we show that (1) enriched environment has protective effects in adult ischemic retinal lesion, while (2) impoverished environment further increases the degree of ischemic injury, and (3) that these environmental effects are gender-dependent: females are less responsive to the positive effects of environmental enrichment and more vulnerable to retinal ischemia in social isolation. In summary, our present study shows that the effects of both positive and negative environmental stimuli are gender-dependent in ischemic retinal lesions. [ABSTRACT FROM AUTHOR]

Abstract: The reaction pathways for the oxidation by O2 of polycyclic aromatic hydrocarbons present in soot particles are investigated using density functional theory at B3LYP/6-311++G(d,p) level of theory. For this, pyrene radical (4-pyrenyl) is chosen as the model molecule, as most soot models present in the literature employ the reactions involving the conversion of 4-pyrenyl to 4-phenanthryl by O2 and OH to account for soot oxidation. Several routes for the formation of CO and CO2 are proposed. The addition of O2 on a radical site to form a peroxyl radical is found to be barrierless and exothermic with reaction energy of 188kJ/mol. For the oxidation reaction to proceed further, three pathways are suggested, each of which involve the activation energies of 104, 167 and 115kJ/mol relative to the peroxyl radical. The effect of the presence of H atom on a carbon atom neighboring the radical site on the energetics of carbon oxidation is assessed. Those intermediate species formed during oxidation with seven-membered rings or with a phenolic group are found to be highly stable. The rate constants evaluated using transition state theory in the temperature range of 300–3000K for the reactions involved in the mechanism are provided. [Copyright &y& Elsevier]

Volatile anaesthetic agents have been recognized for their neuroprotective properties since the 1960s. However, little is known regarding the potential retinoprotective effects of preconditioning by anaesthetic drugs. Retinal ischemia can be modeled by permanent bilateral common carotid artery occlusion (BCCAO). Here we studied the degree of ischemic injury with preconditioning by sevoflurane in the rat retina. During the BCCAO operation and preconditioning Wistar rats were anaesthetized with 1 MAC of sevoflurane. The oxygen, carbon dioxide, and anaesthetic vapor concentration in the anaesthetizing box was monitored with a gas analyzer. We examined 4 groups: non- and preconditioning groups in control and BCCAO animals. The duration of preconditioning period was 1 h and it was performed 1 day before BCCAO. The retinas were processed for histological evaluation after 2 weeks survival to determine the cell number in the ganglion cell layer and the thickness of the whole retina and that of all retinal layers. BCCAO-induced retinal ischemic injury was ameliorated by sevoflurane preconditioning. Retinal thickness and the cell number in the ganglion cell layer were more retained in preconditioned animals after BCCAO compared to non-preconditioned group. These results suggest that preconditioning using sevoflurane could provide a new perspective in retinoprotective strategies. [ABSTRACT FROM AUTHOR]

Retinal ischemia can be effectively modeled by permanent bilateral common carotid artery occlusion, which leads to chronic hypoperfusion-induced degeneration in the entire rat retina. The complex pathways leading to retinal cell death offer a complex approach of neuroprotective strategies. In the present review we summarize recent findings with different neuroprotective candidate molecules. We describe the protective effects of intravitreal treatment with: (i) urocortin 2; (ii) a mitochondrial ATP-sensitive K+ channel opener, diazoxide; (iii) a neurotrophic factor, pituitary adenylate cyclase activating polypeptide; and (iv) a novel poly(ADP-ribose) polymerase inhibitor (HO3089). The retinoprotective effects are demonstrated with morphological description and effects on apoptotic pathways using molecular biological techniques. [ABSTRACT FROM AUTHOR]

Diabetes and hypertension are complex pathologies with increasing prevalence nowadays. Their interconnected pathways are frequently manifested in retinopathies. Severe retinal consequences and their tight connections as well as their possible treatments are particularly important to retinal research. In the present, work we induced diabetes with streptozotocin in spontaneously hypertensive rats and treated them either with PACAP or olaparib and alternatively with both agents. Morphological and immunohistochemical analyses were carried out to describe cell-specific changes during pathologies and after different treatments. Diabetes and hypertension caused massive structural and cellular changes especially when they were elicited together. Hypertension was crucial in the formation of ONL and OPL damage while diabetes caused significant differences in retinal thickness, OPL thickness and in the cell number of the GCL. In diabetes, double neuroprotective treatment ameliorated changes of calbindin-positive cells, rod bipolar cells and dopaminergic amacrine cells. Double treatment was curative in hypertensive diabetic rat retinas, especially in the case of rod bipolar and parvalbumin-positive cells compared to untreated or single-treated retinas. Our results highlighted the promising therapeutic benefits of olaparib and PACAP in these severe metabolic retinal disorders. [ABSTRACT FROM AUTHOR]