1,016 research outputs found
Pigment epithelium-derived factor (PEDF) attenuated capsaicin-induced neurotrophic keratouveitis
PURPOSE. To reveal the influence of retrobulbar capsaicin treatment on rats' eyes and to test the protective effects of PEDF, a known neurotrophic and antiangiogenic substance, against neurotrophic keratouveitis. METHODS. A single retrobulbar injection of capsaicin (50 mg/kg) was performed in young rats, and the effect of subsequent retrobulbar injections of PEDF 3.2 or 6.4 mu g was recorded. Tear fluid alterations were evaluated with the Schirmer test and corneal alterations with slit lamp biomicroscopy. Histopathologic alterations were studied with light and electron microscopy. The number of leukocytes (myeloid cells) in the anterior and posterior chambers, peripheral retina, and vitreous were quantitatively evaluated. RESULTS. Reduced tear secretion was found in capsaicin-treated rats compared with the control, but this effect was significantly attenuated by PEDF. Corneal ulceration developed and was followed by scar formation and neovascularization in the capsaicin-treated, and it was also significantly attenuated by PEDF treatment. Leukocyte infiltration of the anterior and posterior chambers, as well as the peripheral retina and vitreous, was also observed in capsaicin-treated eyes and was significantly reduced by PEDF treatment. The protective effects of PEDF were dose dependent for each parameter, even if the treatment was initiated at day 14 after the challenge. CONCLUSIONS. PEDF accelerated the recovery of tear secretion and also prevented capsaicin-induced neurotrophic keratouveitis and peripheral vitreoretinal inflammation. These effects of PEDF, described herein for the first time, may have a clinical application in inflammatory and neovascular diseases of the eye. (Invest Ophthalmol Vis Sci. 2009;50:5173-5180) DOI:10.1167/iovs.08-185
A mikroflóra és a bélnyálkahártya kölcsönhatása az irritábilis bél, irritábilis szem és irritábilis elme szindróma kórtanában és kezelésében
Accumulating clinical evidence supports co-morbidity of irritable bowel, irritable eye and irritable mind symptoms. Furthermore, perturbation of the microbiota-host symbiosis (dysbiosis) is considered a common pathogenic mechanism connecting gastrointestinal, ocular and neuropsychiatric symptoms. Consequently, maintaining or restoring microbiota-host symbiosis represents a new approach to treat these symptoms or to prevent their relapses. Current treatment approach assigned a primary role to live probiotics alone or in combination with prebiotics to enhance colonization of beneficial bacteria and to strengthen the symbiosis. However, several papers showed major benefits of heat-killed probiotics as compared to their live counterparts on both intestinal and systemic symptoms. Recently, in addition to killing probiotics, in a proof of concept study lysates (fragments) of probiotics in combination with vitamins A, B, D and omega 3 fatty acids were successfully tested. These findings suggested a conceptual change in the approach addressed to both the microbiota and host as targets for intervention. Orv. Hetil., 2014, 155(37), 1454-1460
Action minimizing orbits in the n-body problem with simple choreography constraint
In 1999 Chenciner and Montgomery found a remarkably simple choreographic
motion for the planar 3-body problem (see \cite{CM}). In this solution 3 equal
masses travel on a eight shaped planar curve; this orbit is obtained minimizing
the action integral on the set of simple planar choreographies with some
special symmetry constraints. In this work our aim is to study the problem of
masses moving in \RR^d under an attractive force generated by a potential
of the kind , , with the only constraint to be a simple
choreography: if are the orbits then we impose the
existence of x \in H^1_{2 \pi}(\RR,\RR^d) such that q_i(t)=x(t+(i-1) \tau),
i=1,...,n, t \in \RR, where . In this setting, we first
prove that for every d,n \in \NN and , the lagrangian action
attains its absolute minimum on the planar circle. Next we deal with the
problem in a rotating frame and we show a reacher phenomenology: indeed while
for some values of the angular velocity minimizers are still circles, for
others the minima of the action are not anymore rigid motions.Comment: 24 pages; 4 figures; submitted to Nonlinearit
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Prevalence of diverse genders and sexualities in Australia and associations with five forms of child maltreatment and multi-type maltreatment
This study presents the most comprehensive national prevalence estimates of diverse gender and sexuality identities in Australians, and the associations with five separate types of child maltreatment and their overlap (multi-type maltreatment). Using Australian Child Maltreatment Study (ACMS) data (N = 8503), 9.5% of participants identified with a diverse sexuality and.9% with a diverse gender. Diverse identities were more prevalent in the youth cohort, with 17.7% of 16–24 years olds identifying with a diverse sexuality and 2.3% with a diverse gender. Gender and sexuality diversity also intersect – for example, with women (aged 16–24 and 25–44) more likely than men to identify as bisexual. The prevalence of physical abuse, sexual abuse, emotional abuse, neglect and exposure to domestic violence was very high for those with diverse sexuality and/or gender identities. Maltreatment was most prevalent for participants in the youth cohort with diverse gender identities (90.5% experiencing some form of child maltreatment; 77% multi-type maltreatment) or diverse sexualities (85.3% reporting any child maltreatment; 64.3% multi-type maltreatment). The strong association found between child maltreatment and diverse sexuality and gender identities is critical for understanding the social and mental health vulnerabilities of these groups, and informing services needed to support them.</p
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Adaptation and validation of the Juvenile Victimization Questionnaire-R2 for a national study of child maltreatment in Australia
Background: To establish national prevalence of child maltreatment, reliable, valid and contextually appropriate measurement is needed. This paper outlines the refinement, adaptation and testing of child maltreatment sections of the Juvenile Victimization Questionnaire (JVQ)-R2 for use in the Australian context. Methods: Three phases were undertaken: 1) Conceptual analysis of the five forms of child maltreatment (physical abuse, sexual abuse, emotional or psychological abuse, neglect, and experience of domestic violence), item mapping and review, item development, and independent expert review; 2) Cognitive testing with members of the general population, and individuals who have experienced maltreatment; and 3) Pilot testing and quantitative psychometric assessment with a random sample of Australians aged 16–65+ years. Results: The final measure included a total of 17 child maltreatment screener items, assessing Physical Abuse (2 items), Sexual abuse (5 items (including 2 non-contact items and 3 contact items), Emotional Abuse (3 items), Neglect (3 items), and Experience of Domestic Violence (4 items). Screener items were also included on corporal punishment (1 item), and internet sexual victimization (2 items). The final 17-item revised JVQ had high face and conceptual validity and good internal reliability (α = 0.86 and Ω = 0.87). Test re-test reliability was moderate to high for individual screeners ranging from k = 0.45 to 0.89. Conclusions: Results indicate the Juvenile Victimization Questionnaire-R2: Adapted Version (Australian Child Maltreatment Study) is a suitable instrument for assessing population-wide prevalence of maltreatment. It is congruent with conceptual models of maltreatment and shows good reliability and validity in this Australian sample.</p
Latent disconnectome prediction of long-term cognitive-behavioural symptoms in stroke
Stroke significantly impacts the quality of life. However, the long-term cognitive evolution in stroke is poorly predictable at the individual level. There is an urgent need to better predict long-term symptoms based on acute clinical neuroimaging data. Previous works have demonstrated a strong relationship between the location of white matter disconnections and clinical symptoms. However, rendering the entire space of possible disconnection-deficit associations optimally surveyable will allow for a systematic association between brain disconnections and cognitive-behavioural measures at the individual level. Here we present the most comprehensive framework, a composite morphospace of white matter disconnections (disconnectome) to predict neuropsychological scores 1 year after stroke. Linking the latent disconnectome morphospace to neuropsychological outcomes yields biological insights that are available as the first comprehensive atlas of disconnectome-deficit relations across 86 scores-a Neuropsychological White Matter Atlas. Our novel predictive framework, the Disconnectome Symptoms Discoverer, achieved better predictivity performances than six other models, including functional disconnection, lesion topology and volume modelling. Out-of-sample prediction derived from this atlas presented a mean absolute error below 20% and allowed personalize neuropsychological predictions. Prediction on an external cohort achieved an R2 = 0.201 for semantic fluency. In addition, training and testing were replicated on two external cohorts achieving an R2 = 0.18 for visuospatial performance. This framework is available as an interactive web application (http://disconnectomestudio.bcblab.com) to provide the foundations for a new and practical approach to modelling cognition in stroke. We hope our atlas and web application will help to reduce the burden of cognitive deficits on patients, their families and wider society while also helping to tailor future personalized treatment programmes and discover new targets for treatments. We expect our framework's range of assessments and predictive power to increase even further through future crowdsourcing
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