Occlusion of retinal capillaries caused by glial cell proliferation in chronic ocular inflammation

The inner blood-retinal barrier is a gliovascular unit in which glial cells surround capillary endothelial cells and regulate retinal capillaries by paracrine interactions. During chronic ocular inflammation, microvascular complications can give rise to vascular proliferative lesions, which compromise visual acuity. This pathologic remodelling caused by proliferating Müller cells determines occlusion of retinal capillaries. The aim of the present study was to identify qualitative and quantitative alterations in the retinal capillaries in patients with post-traumatic chronic ocular inflammation or post-thrombotic vascular glaucoma. Moreover, we investigated the potential role of vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines in retinal inflammation. Our electron microscopy findings demonstrated that during chronic ocular inflammation, thickening of the basement membrane, loss of pericytes and endothelial cells and proliferation of Müller cells occur with irreversible occlusion of retinal capillaries. Angiogenesis takes place as part of a regenerative reaction that results in fibrosis. We believe that VEGF and pro-inflammatory cytokines may be potential therapeutic targets in the treatment of this disease although further studies are required to confirm these findings

Age and diabetes related changes of the retinal capillaries: an ultrastructural and immunohistochemical study

Normal human aging and diabetes are associated with a gradual decrease of cerebral flow in the brain with changes in vascular architecture. Thickening of the capillary basement membrane and microvascular fibrosis are evident in the central nervous system of elderly and diabetic patients. Current findings assign a primary role to endothelial dysfunction as a cause of basement membrane (BM) thickening, while retinal alterations are considered to be a secondary cause of either ischemia or exudation. The aim of this study was to reveal any initial retinal alterations and variations in the BM of retinal capillaries during diabetes and aging as compared to healthy controls. Moreover, we investigated the potential role of vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines in diabetic retina.Transmission electron microscopy (TEM) was performed on 46 enucleated human eyes with particular attention to alterations of the retinal capillary wall and Müller glial cells. Inflammatory cytokines expression in the retina was investigated by immunohistochemistry.Our electron microscopy findings demonstrated that thickening of the BM begins primarily at the level of the glial side of the retina during aging and diabetes. The Müller cells showed numerous cytoplasmic endosomes and highly electron-dense lysosomes which surrounded the retinal capillaries. Our study is the first to present morphological evidence that Müller cells start to deposit excessive BM material in retinal capillaries during aging and diabetes. Our results confirm the induction of pro-inflammatory cytokines TNF-α and IL-1β within the retina as a result of diabetes.These observations strongly suggest that inflammatory cytokines and changes in the metabolism of Müller glial cells rather than changes in of endothelial cells may play a primary role in the alteration of retinal capillaries BM during aging and diabetes

Internal and external aspects of freedom of choice in mental health: cultural and linguistic adaptation of the Hungarian version of the Oxford CAPabilities questionnaire—Mental Health (OxCAP-MH)

Background: A link between mental health and freedom of choice has long been established, in fact, the loss of freedom of choice is one of the possible defining features of mental disorders. Freedom of choice has internal and external aspects explicitly identified within the capability approach, but received little explicit attention in capability instruments. This study aimed to develop a feasible and linguistically and culturally appropriate Hungarian version of the Oxford CAPabilities questionnaire—Mental Health (OxCAP-MH) for mental health outcome measurement. Methods: Following forward and back translations, a reconciled Hungarian version of the OxCAP-MH was developed following professional consensus guidelines of the International Society for Pharmacoeconomics and Outcomes Research and the WHO. The wording of the questionnaire underwent cultural and linguistic validation through content analysis of cognitive debriefing interviews with 11 Hungarian speaking mental health patients in 2019. Results were compared with those from the development of the German version and the original English version with special focus on linguistic aspects. Results: Twenty-nine phrases were translated. There were linguistic differences in each question and answer options due to the high number of inflected, affixed words and word fragments that characterize the Hungarian language in general. Major linguistic differences were also revealed between the internal and external aspects of capability freedom of choices which appear much more explicit in the Hungarian than in the English or German languages. A re-analysis of the capability freedom of choice concepts in the existing language versions exposed the need for minor amendments also in the English version in order to allow the development of future culturally, linguistically and conceptually valid translations. Conclusion: The internal and external freedom of choice impacts of mental health conditions require different care/policy measures. Their explicit consideration is necessary for the conceptually harmonised operationalisation of the capability approach for (mental) health outcome measurement in diverse cultural and linguistic contexts

A probabilistic demand side management approach by consumption admission control

Nova generacija električne mreže pod nazivom pametna mreža (Smart Grid) je nedavno zamišljena vizija čišćeg, učinkovitijeg i jeftinijeg elektroenergetskog sustava. Jedan od najvećih izazova električne mreže je da bi proizvodnja i potrošnja trebale biti uravnotežene u svakome trenutku. U radu se uvodi novi koncept za kontrolu potrošnje sredstvima automatski omogućavanih/onemogućavanih električnih aparata kako bi bili sigurni da je potrošnja usklađena s raspoloživim zalihama, na temelju statističkih karakterizacija potreba. U našem novom pristupu, umjesto uporabe tvrdih granica procjenjujemo vjerojatnost kraja distribucije potrošnje i sustava kontrole pomoću načela i rezultata statističkog upravljanja resursima.New generation electricity network called Smart Grid is a recently conceived vision for a cleaner, more efficient and cheaper electricity system. One of the major challenges of electricity network is that generation and consumption should be balanced at every moment. This paper introduces a new concept for controlling the demand side by the means of automatically enabling/disabling electric appliances to make sure that the demand is in match with the available supplies, based on the statistical characterization of the need. In our new approach instead of using hard limits we estimate the tail probability of the demand distribution and control system by using the principles and the results of statistical resource management

PHYSIOLOGICAL MARKERS OF DUCKWEED (Lemna minor L.) FOR BIOINDICATION OF WATER POLLUTION WITH COPPER AND DIURON (3-(3,4-DICHLOROPHENYL)-1,1-DIMETHYLUREA)

Abstract. Lesser duckweed (Lemna minor L.) is a cosmopolitan aquatic test plant, its growth and metabolic parameters are useful markers of the influence exerted on living organisms by changes in water quality. We have investigated the influence of water-polluting copper and herbicides on net biomass production, photosynthetic pigment content and efficiency parameters of induced chlorophyll fluorescence of duckweed. Copper decreased biomass production of duckweed only at higher concentrations (100 µM), while diuron inhibited growth even at 10 µM. With respect to the light-harvesting complexes of chloroplasts, the molar ratios between the main types of photosynthetic pigments proved to be the most sensitive markers of the impact of the applied water-polluting agents. In case of water pollution with copper and diuron, the mostly sensitive parameters of induced chlorophyll fluorescence were the potential quantum yield efficiency and the vitality index of photosynthetic apparatus, these parameters being recommended for bioindication of water pollution