Wyniki wyszukiwania - Biblioteka Nauki

1

Plasticity of the primate visual pathway following lesions in early and mature life

100%

Rosa M.

Acta Neurobiologiae Experimentalis

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2019

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tom 79

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nr Suppl.1

XX

In primates, visual function is dominated by the pathway that transmits visual information from the retina, via the lateral geniculate nucleus (LGN), to the primary visual cortex (V1). Although lesions of V1 lead to blindness, it is well documented that residual visual function can be retained within scotomas caused by V1 lesions, including (largely subconscious) abilities to locate some types of stimuli, and even to coarsely evaluate their characteristics (“blindsight”). These observations indicate that other thalamic projections can convey retinal inputs directly to the extrastriate cortex, bypassing V1. The exact characteristics of blindsight depend markedly on the age at which the lesion occurs. Patients and monkeys who sustained lesions early in life often show a greater range of abilities than those who had lesions in adulthood, including, in many cases, conscious perception. My laboratory has been investigating the types of physiological changes in subcortical and cortical areas which mediate such outcomes. For this purpose, we have developed a V1 lesion model based on the marmoset monkey, a small new world primate in which the anatomy and physiology of the visual pathways has been well characterised, and has accelerated development in comparison with macaque monkeys. In this talk, I will briefly review the characteristics of the marmoset as an advantageous animal model for studies of primate vision, including plasticity, describe recent findings on the physiological consequences of V1 lesions at different ages, and briefly report on current lines of work aimed at understanding the full circuitry of the marmoset visual cortex using a neuroinformatics approach.

2

hnRNP-R regulates the PMA-induced c-fos expression in retinal cells

100%

Huang J. , Li S.-J. , Chen X.-H. , Han Y. , Xu P.

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tom 13

|

nr 2

303-311

EN

This study focused on the function of hnRNP-R in the regulation of c-fos expression. We demonstrated that hnRNP-R accelerated the rise and decline phases of c-fos mRNAs and Fos proteins, allowing PMA to induce an augmented pulse response of c-fos expression. Then, we examined the role of the c-fos-derived AU-rich element (ARE) in hnRNP-R-regulated mRNA degradation. Studies with the ARE-GFP reporter gene showed that hnRNP-R significantly reduced the expression of GFP with an inserted ARE. Moreover, immunoprecipitation-RT-PCR analysis demonstrated that in R28 cells and rat retinal tissues, the c-fos mRNA was co-immunoprecipitated with hnRNP-R. These findings indicate that hnRNP-R regulates the c-fos expression in retinal cells, and that the ARE of c-fos mRNAs contributes to this regulation.

3

Photoreceptor guanylate cyclase variants: cGMP production under control.

100%

Sokal I. , Alekseev A. , Palczewski K.

Acta Biochimica Polonica

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2003

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tom 50

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nr 4

1075-1095

EN

Changes in the Ca2+ concentration are thought to affect many processes, including signal transduction in a vast number of biological systems. However, only in few cases the molecular mechanisms by which Ca2+ mediates its action are as well understood as in phototransduction. In dark-adapted photoreceptor cells, the equilibrium level of cGMP is maintained by two opposing activities, such as phosphodiesterase (PDE) and guanylate cyclase (GC). Upon absorption of photons, rhodopsin-G-protein-mediated activation of PDE leads to a transient decrease in [cGMP] and subsequently to lowering of [Ca2+]. In turn, lower [Ca2+] increases net production of cGMP by stimulation of GC until dark conditions are re-established. This activation of GC is mediated by Ca2+-free forms of Ca2+-binding proteins termed GC-activating proteins (GCAPs). The last decade brought the molecular identification of GCs and GCAPs in the visual system. Recent efforts have been directed toward understanding the properties of GC at the physiological and structural levels. Here, we summarize the recent progress and present a list of topics of ongoing research.

4

The Effect of Return Electrode Position on Induced Electric Fields for Electrical Stimulation of Retinal Ganglion Cells

100%

Celik M.

Acta Physica Polonica A

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2017

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tom 132

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nr 3

493-495

EN

Age-related macular degeneration and retinitis pigmentosa are the most countered eye diseases that damage photoreceptors and cause to lose the visual sense. To regain the visual sense, studies are focused on the electrical stimulation of nerve cells remain intact. The electrical stimulation is carried out with the electrode arrays that include a certain number of stimulation electrodes and a common return electrode. In this study, the retinal stimulation is modelled using a computational model to investigate stimulation performance depending on the return electrode position and its geometrical properties. Stimulation induced electric field, current density and temperature over the retinal tissue are examined. It is seen that closer placement of return electrode and stimulation electrodes causes high electric field intensity and current density between electrodes, which is quite risky for long term chronic implementation by the reason of the increase in the temperature beyond the safe limits. It is concluded that there is an indispensability for the distances, three to five times of the electrode diameter, between electrodes to avoid electrode corrosion and tissue damage.

5

Wpływ zmiennego pola magnetycznego na funkcje narządu wzroku

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Sztafrowski D. , Jakubaszko J.

Przegląd Elektrotechniczny

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2005

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tom R. 81, nr 4

25-29

PL

Artykuł opisuje obserwowane na stanowiskach pracy zjawisko oddziaływania zmiennego pola magnetycznego na narząd wzroku. Rejestrowane wartości indukcji magnetycznej znajdują się w przedziale 2-150mT. Pracownicy sygnalizowali występowanie w tych okolicznościach zaburzenia widzenia. W miejscach pracy, gdzie może występować zmienne pole magnetyczne o wartościach indukcji większych niż 2 mT, personel powinien być poinformowany o możliwości występowania zaburzeń widzenia w celu zapobieżenia ewentualnym wypadkom przy pracy. Obserwowane zjawisko wymaga dalszych szczegółowych badań.

EN

It has been observed that exposure to extremely Iow frequency electro-magnetic fields induce some changes in vision process. Some laboratory workers complained about visual abnormalities during exposure on magnetic field ranged from 2 to 150 mT. It is important to warn and protect persons from harmful influence of this factor in order to avoid accidents at work. Further research is needed to clarify this issue.

6

p19 detected in the rat retina and pineal gland is a guanylyl cyclase-activating protein (GCAP).

100%

Dejda A. , Matczak I. , Gorczyca W. A.

Acta Biochimica Polonica

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2002

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tom 49

|

nr 4

899-905

EN

The Ca2+-dependent activation of retina-specific guanylyl cyclase (retGC) is mediated by guanylyl cyclase-activating proteins (GCAPs). Here we report for the first time detection of a 19 kDa protein (p19) with GCAP properties in extracts of rat retina and pineal gland. Both extracts stimulate synthesis of cGMP in rod outer segment (ROS) membranes at low (30 nM) but not at high (1 mM) concentrations of Ca2+. At low Ca2+, immunoaffinity purified p19 activates guanylyl cyclase(s) in bovine ROS and rat retinal membranes. Moreover, p19 is recognized by antibodies against bovine GCAP1 and, similarly to other GCAPs, exhibits a Ca2+-dependent electrophoretic mobility shift.

7

Bevacizumab in age-related macular degeneration – comparison of subjective estimation of vision with objective test results

100%

Piotrowska-Gwóźdź A. , Piotrowska-Seweryn A. , Mazur-Piotrowska G.

Annales Academiae Medicae Silesiensis

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2015

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tom 69

33-41

EN

PURPOSE: Anti-VEGF therapy plays a great role in medicine, especially in opthalmology. The aim of the therapy is to inhibit the VEGF-A factors that are responsible for the angiogenesis in diseases such as the wet form of age-related macular degeneration (AMD). One of the monoclonal anti-VEGF antibodies is bevacizumab (Avastin®; Genentech, Inc., South San Francisco, CA). The aim of the study was to compare the subjective estimation of visual acuity with objective test results in patients undergoing anti-VEGF therapy using Avastin. MATERIALS AND METHODS: The authors report a study of 57 patients (37 females and 20 males) with exudative AMD whose near and distance visual acuity was examined before the first dose of Avastin and 1 month after the third injection. Additionally, an original questionnaire evaluating the subjective state of vision during the activities of daily routine was performed. RESULTS: When examining distance visual acuity, 29 patients made an improvement, deterioration was reported in 5 cases and in 23 cases the results remained unaltered. The results were correlated with the subjective estimation. CONCLUSIONS 1. Avastin stabilizes the degeneration process of AMD in most patients and sometimes improves visual acuity. 2. There is a positive correlation between the objective test results and subjective opinion in patients undergoing anti-VEGF therapy using Avastin.

PL

WSTĘP: Terapia anti-VEGF odgrywa niezwykle istotną rolę w medycynie, zwłaszcza w okulistyce. Polega na hamowaniu czynnika VEGF-A, który jest odpowiedzialny za angiogenezę w takich chorobach, jak wysiękowa postać zwyrodnienia plamki związanego z wiekiem (age-related macular degeneration – AMD). Jednym z przeciwciał monoklonalnych skierowanych przeciwko VEGF jest bevacizumab (Avastin®; Genentech, Inc., South San Francisco, CA). Celem badania jest porównanie subiektywnej oceny widzenia z obiektywnymi wynikami badań u pacjentów poddanych terapii anty-VEGF z zastosowaniem Avastinu. MATERIAŁ I METODY: Badaniem objęto 57 pacjentów (37 kobiet 20 mężczyzn) z wysiękową postacią AMD, u których dokonano oceny ostrości wzorku do bliży i dali przed pierwszą dawką i miesiąc po trzeciej iniekcji doszklistkowej Avastinu. Dodatkowo przeprowadzono autorską ankietą oceniającą widzenie podczas wykonywania czynności życia codziennego. WYNIKI: Analizując wyniki ostrości wzroku dla dali 29 pacjentów wykazało poprawę, 5 pogorszenie widzenia, a w 23 przypadkach ostrość wzroku nie uległa zmianie. Wykazano dodatnią korelację powyższych danych z wynikami subiektywnej oceny. WNIOSKI: 1. Avastin stabilizuje proces chorobowy w wysiękowej postaci AMD, a u niektórych pacjentów obserwowana jest poprawa ostrości widzenia. 2. Istnieje dodatnia korelacja między obiektywnymi wynikami ostrości wzroku a subiektywną oceną widzenia u pacjentów poddanych terapii anty-VEGF z zastosowaniem Avastinu.

8

Accumulation of membranes and photoreceptor degeneration in mouse retina

100%

Kralj M. , Pipan N.

Folia Morphologica

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1998

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tom 57

|

nr 4

9

Morphometric study of the human embryonic retina

100%

Styszynski A. , Wozniak W. , Bruska M.

Folia Morphologica

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1998

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tom 57

|

nr 3

10

p19 detected in the rat retina and pineal gland is a guanylyl cyclase-activating protein [GCAP]

100%

Dejda A. , Matczak I. , Gorczyca W. A.

Acta Biochimica Polonica

|

2002

|

tom 49

|

nr 4

EN

The Ca2+ -dependent activation of retina-specific guanylyl cyclase (retGC) is mediated by guanylyl cyclase-activating proteins (GCAPs). Here we report for the first time detection of a 19 kDa protein (p19) with GCAP properties in extracts of rat retina and pineal gland. Both extracts stimulate synthesis of cGMP in rod outer segment (ROS) membranes at low (30 nM) but not at high (1 uM) concentrations of Ca2+ .AtlowCa2+ , immunoaffinity purified p19 activates guanylyl cyclase(s) in bovine ROS and rat retinal membranes. Moreover, p19 is recognized by antibodies against bovine GCAP1 and, similarly to other GCAPs, exhibits a Ca2+ -dependent electrophoretic mobility shift.

11

D2-dopamine receptor-mediated stimulation of inositol trisphosphate formation in chick retina

100%

Zawilska J. B. , Krzemieniewska B. , Orszulak-Michalak D. , Nowak J. Z.

Acta Neurobiologiae Experimentalis

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1996

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tom 56

|

nr 4

12

Personal identification using retina

84%

Choraś R. S.

Journal of Medical Informatics & Technologies

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2009

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tom Vol. 13

53--58

EN

This paper proposes a biometric system for authentication that uses the retina blood vessel pattern. The retina biometric analyzes the layer of blood vessels located at the back of the eye. The blood vessels at the back of the eye have a unique pattern, from eye to eye and person to person. The retina, a layer of blood vessels located at the back of the eye, forms an identity card for the individual under investigation. In particular retinal recognition creates an ”eye signature” from its vascular configuration and its artificial duplication is thought to be virtually impossible.

13

Histological studies of the retina differentiation in grass snake Natrix natrix L. during embryogenesis

84%

Rupik W. , Bajdak K. , Krzeszowiak K.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2008

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tom 50

|

nr 1

14

Ophthalmic diagnosis based on multispectral imaging

84%

Świtoński A. , Błachowicz T. , Zieliński M. , Misiuk-Hojto M. , Wojciechowski K.

Przegląd Elektrotechniczny

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2011

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tom R. 87, nr 12b

165--168

EN

We have proposed and deployed prototyped multispectral capturing device for the ophthalmic diagnosis. The main component of the device are slit lamp, liquid crystal tunable filter and high sensitive monochrome camera. The applied hardware allows to obtain 21 spectral channels in the visible light range. The device has been calibrated based on the captured images of the colorchecker colors with known RGB and spectral values. The proposed device is focused on the diagnoses of cancer, PEX, galucoma and diabetic retinopathy.

PL

W ramach pracy zaproponowano urządzenie obrazowania wielospektralnego na potrzeby diagnostyki okulistycznej. Główne komponenty urządzenia to lampa szczelinowa, elektrycznie przełączalny filtr ciekłokrystaliczny oraz wysokiej czułości kamera monochromatyczna. Wybrane rozwiązania sprzętowe pozwalają na uzyskanie 21 kanałów spektralnym w zakresie światła widzialnego. Urządzenie zostało skalibrowane na podstawie zdjęć próbnika kolorów. Przewiduje się zastosowania opracowanego urządzenia w diagnostyce zmian nowotworowych, zespołu PEX, jaskry i retinopatii cukrzycowej.

15

Electrophysiology and pharmacology of the optic input to the rat intergeniculate leaflet in vitro

84%

Blasiak A. , Blasiak T. , Lewandowski M. H.

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tom 60

|

nr 1

171-180

EN

The mammalian intergeniculate leaflet (IGL) of the thalamus is a neuronal element of the circadian timing system, which receives direct photic input from the retina. The purpose of this study was to analyze responses of rat IGL neurons in vitro to optic tract stimulation and to identify neurotransmitters released from the terminals of retinal ganglion cells in this structure. Following optic tract stimulation, most of the responding IGL cells were excited and only a minority of them were inhibited. Neurons showing the excitatory response were tested in the presence of AP-5, a selective antagonist of NMDA receptors. In most cases the responses were only partially inhibited by the presence of AP-5. Complete disappearance of excitatory responses was achieved by adding CNQX, an AMPA/kainate receptor-selective antagonist, to the standard incubation fluid. Inhibitory responses were blocked or considerably attenuated in the presence of bicuculline, a GABAA receptor antagonist, in the ACSF. This study demonstrated that glutamate is the main neurotransmitter mediating optic tract input to the IGL, acting mainly via non-NMDA ionotropic receptors. It was also shown that NMDA and GABAA receptors are involved in passing photic input to the IGL, albeit to a much lesser extent.

16

Detection of hard exudates using mean shift and normalized cut method

84%

Banerjee S. , Kayal D.

Biocybernetics and Biomedical Engineering

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2016

|

tom Vol. 36, no. 4

679--685

EN

As diabetic retinopathy (DR) is one of the main causes of loss of vision among diabetic patients, an early detection using automated detection techniques can prevent blindness among diabetic patients. Hard exudates constitute one of the early symptoms of DR and this paper describes a method for its detection using fundus images of retina, employing a combination of morphological operations, mean shift (MS), normalized cut (NC) and Canny's operation. This combined technique avoids over segmentation and at the same time reduces the time complexity while clearly delineating the exudates. Output of the proposed method is evaluated using public databases and produces sensitivity, specificity and accuracy as 98.80%, 98.25% and 98.65%, respectively. The ROC curve gives 0.984 as area under curve. The sensitivity, specificity, accuracy and area under curve of ROC indicate the effectiveness of the method.

17

Expression of the pigment-dispersing factor (PDF) in developing retina of the grass snake Natrix natrix L. (Lepidosauria, Serpentes) embryos. Immunocytochemical studies

84%

Rupik W. , Bembenek J.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2008

|

tom 50

|

nr 1

18

Programmed cell death during retinal development in grass snake Natrix natrix L. (Lepidosauria, Serpentes) embryos

84%

Rupik W. , Bembenek J.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2008

|

tom 50

|

nr 1

19

Ocena bezpieczeństwa fotobiologicznego świateł i lamp LED wykorzystywanych w motoryzacji pod kątem zagrożenia siatkówki oka światłem niebieskim

84%

Legierski M. , Michałek P.

Autobusy : technika, eksploatacja, systemy transportowe

|

2018

|

tom R. 19, nr 6

548--551, CD

PL

Artykuł zawiera wyniki badań dotyczące oceny zagrożenia światłem niebieskim siatkówki oka przez urządzenia świetlne ze źródłami światła LED wykorzystywane w motoryzacji. Badaniom podlegały światła do jazdy dziennej oraz lampy robocze obecnie dostępne na rynku, przeznaczone do samodzielnego montażu w pojazdach. Zaprezentowano metodę badań z wykorzystaniem matrycowego miernika luminancji i spektroradiometru. Wykonano niezbędne badania fotometryczne i radiometryczne w celu oceny zagrożenia według normy PN-EN 62471:2010. Uzyskane wyniki badań odniesiono do światłości maksymalnej, współrzędnych chromatyczności i temperatury barwowej najbliższej badanych urządzeń świetlnych.

EN

The article contains results of the research on the assessment of the blue light retinal hazard by lighting devices used in the automotive with LED light sources. The study was subject to daytime running lights and work lamps available on the market for self-assembly in vehicles. The study method was presented using a matrix luminance meter and spectroradiometer. The necessary photometric and radiometric tests were carried out. Assessment of blue light hazard according to the PN-EN 62471: 2010 was made. Obtained results were referred to maximum luminous intensity, chromaticity coordinates and correlated colour temperature of tested devices.

20

Exudative retinal detachment and optic disc swelling in the course of posterior scleritis: case study and literature review

84%

Michali M. , Pławszewski R. , Sutor E.

OphthaTherapy

|

2022

|

tom 9

|

nr 4

231-235

PL

Cel: Celem tej pracy jest przedstawienie rzadkiego przypadku tylnego zapalenia twardówki z wysiękowym odwarstwieniem siatkówki oraz obrzękiem tarczy nerwu wzrokowego. Metody: Przedstawiono przypadek 28-letniego pacjenta z jednostronnym tylnym zapaleniem twardówki, z wysiękowym odwarstwieniem siatkówki oraz obrzękiem tarczy nerwu wzrokowego. Pacjent wykazywał spadek ostrości wzroku oraz stan zapalny w ścianie gałki ocznej oka prawego. Wyniki: Przy przyjęciu w badaniu okulistycznym oka prawego rozpoznano odwarstwienie siatkówki we wszystkich kwadrantach, podsiatkówkowy materiał wysiękowy, fałdy naczyniówki oraz brak patologii w przednim odcinku oka. W badaniu ultrasonografii w projekcji B tylne pogrubienie twardówki rzędu 2.0 mm oraz całkowite odwarstwienie siatkówki oka prawego. W badaniu ostrości wzroku: OP = 1/50 sc, OL = 45/50 sc. Rozpoznano podwyższone ciśnienie wewnątrzgałkowe oka prawego rzędu 44.0mmHg. Wykonano tomografię komputerową oczodołów z kontrastem, która wykazała znaczną asymetrię wielkości gałek ocznych (prawa 22x22 mm, lewa 21x21mm) oraz pogrubienie ściany prawej gałki ocznej w części tylnej do 2.0mm. W drugiej dobie hospitalizacji w badaniu okulistycznym dodatkowo rozpoznano zatarte granice nerwu wzrokowego oka prawego. Zastosowano leczenie systemowe: sterydoterapię, niesterodiowe leki przeciwzapalne oraz leki obniżające ciśnienie wewnątrzgałkowe. Zastosowano również leczenie miejscowe oka prawego. Wykonano szereg badań laboratoryjnych, wykluczając choroby układowe mogące być przyczyną tylnego zapalenia twardówki. Pacjent pozostawał pod opieką przyszpitalnej poradni okulistycznej stosując sterydoterapię miejscową oraz systemową. Sterydoterapia sytemowa była utrzymywana przez okres kilku miesięcy, stopniowo zmniejszając dawkę. Podczas kontrolnych wizyt ostrość wzroku utrzymywała się na poziomie: OP=40/50 sc, OL = 45/50 sc. Wnioski: Tylne zapalenie twardówki jest chorobą wymagającą szybkiej diagnozy oraz leczenia systemowego.

EN

Objectives: The objective of the present paper is to present a rare case of posterior scleritis with exudative retinal detachment and optic disc oedema. Materials: The paper discusses a case of a 28-year-old patient with unilateral posterior scleritis, exudative retinal detachment and optic disc oedema. The patient presented with reduced visual acuity and inflammation within his right eyeball coat. Test results: Upon admission, retinal detachment in all quadrants was diagnosed, with subretinal exudate, choroidal folds, but no pathology involving the anterior segment. B projection ultrasound revealed thickening of the posterior sclera of around 2.0 mm and complete retinal detachment in the right eye. Visual acuity results were OD = 1/50 Sc, OS = 45/50 Sc. Elevated intraocular pressure of the right eye was detected at 44.0 mmHg A CT scan of the orbits with contrast revealed significant asymmetry of the eyeballs (right 22 × 22 mm, left 21 × 21 mm) as well as posterior thickening of the right eyeball coat to 2.0 mm. On top of that, on the second day of the patient’s hospital stay, an ophthalmic exam showed obscured borders of the right optic nerve. Systemic treatment was initiated, comprising steroids, non-steroidal anti-inflammatory drugs and intraocular pressure lowering drugs. Additionally, topical treatment was provided with regard to the right eye. A number of laboratory tests were carried out to rule out systemic diseases that could have caused posterior scleritis. After discharge, the patient received follow up care from the hospital’s ophthalmology clinic and remained on topical and systemic steroids. Oral systemic steroid therapy was maintained over a period of a few months, with gradual dose reduction. At follow-up visits, his visual acuity remained stable at OD = 40/50 Sc, OS = 45/50 Sc. Conclusions: Posterior scleritis is a condition that requires prompt diagnosis and systemic treatment.