Localization of Caveolin-1 and C-SRC in Mature and Differentiating Photoreceptors: Raft Proteins Co-Distribute With Rhodopsin During Development

Numerous biochemical and morphological studies have provided insight into the distribution pattern of caveolin-1 and the presence of membrane rafts in the vertebrate retina. To date however, studies have not addressed the localization profile of raft specific proteins during development. Therefore the purpose of our studies was to follow the localization pattern of caveolin-1, phosphocaveolin-1 and c-src in the developing retina and compare it to that observed in adults. Specific antibodies were used to visualize the distribution of caveolin-1, c-src, a kinase phosphorylating caveolin-1, and phospho-caveolin-1. The labeling pattern of this scaffolded complex was compared to those of rhodopsin and rhodopsin kinase. Samples were analyzed at various time points during postnatal development and compared to adult retinas. The immunocytochemical studies were complemented with immunoblots and immunoprecipitation studies. In the mature retina caveolin-1 and c-src localized mainly to the cell body and IS of photoreceptors, with only very weakly labeled OS. In contrast, phospho-caveolin-1 was only detectable in the OS of photoreceptors. During development we followed the expression and distribution profile of these proteins in a temporal sequence with special attention to the period when OS formation is most robust. Double labeling immunocytochemistry and immunoprecipitation showed rhodopsin to colocalize and co-immunoprecipitate with caveolin-1 and c-src. Individual punctate structures between the outer limiting membrane and the outer plexiform layer were seen at P10 to be labeled by both rhodopsin and caveolin-1 as well as by rhodopsin and c-src, respectively. These studies suggest that membrane raft specific proteins are co-distributed during development, thereby pointing to a role for such complexes in OS formation. In addition, the presence of small punctate structures containing caveolin-1, c-src and rhodopsin raise the possibility that these proteins may transport together to OS during development and that caveolin-1 exists predominantly in a phosphorylated form in the OS

A fotoreceptor-fejlődés sejt- és molekuláris biológiája = Cell and molecular biology of photoreceptor development

Az opszinváltás szabályozása fajonként eltérő, tiroxin és TRbéta2 nélkülözhetetlen a zöld csapfejlődéshez. A receptormegoszlás időbeli és térbeli mintázatával igazoltuk a tiroxint mediáló TRbéta2 szerepét. Tenyésztő módszerünkkel a fotoreceptor-differenciálódás szérummentes környezetben is végbemegy, a világon először definitív médiumban vizsgálható. Más faktorok (A- és E-vitamin, BDNF) is hatnak a pigment-expresszióra. Szelektív neurotrophin antagonisták az opszin és a TrkB receptor kapcsoltságára utalnak. Az erythropoietin retinális expressziója HIF1-α szabályozás alatt áll és időben változik a fejlődés korai szakaszában. Szemnyitás után a retinában lecsökken a transzdukciós molekulák szintje, kivéve a fotoreceptorokat. A sejttestben szintetizálódnak, közös lipid rafton kerülnek a kültagba és játszanak szerepet a fejlődésben. Az STK38L gén homozigóta mutációja befolyásolja a fotoreceptor-fejlődést. Sejthalál és proliferáció egyaránt jelen van. Hibrid sejtek jelennek meg pálcika-, kisebb mértékben S-opszin termeléssel. A differenciált, mutáns sejtek a degenerációs gén hatására megőrzik osztódóképességüket. A melatonin éjszaka termelődik, éjjeli világítás a hormontermelés gátlásával patológiás folyamatokat (emlő és colorectalis carcinoma) okozhat. A pineális szerv emlősben elvesztette fotoreceptor működését és szimpatikus rostokon a retinából kap információt. Mivel a pineális melatoninképzést rövidhullámú fény gátolja, éjjeli műszakban hosszúhullámú megvilágítást kell használni. | Regulation of opsin-switch varies across species. Thyroxin and TRß2 receptor is essential for green cone development. Spatial and temporal receptor distribution proved the role of TRß2 mediating thyroxin. Photoreceptor differentiation is completed in our culture method in serum-free medium, allowing its examination in a definitive paradigm. Other factors such as Vitamins A and E, BDNF) also influence visual pigment expression. Selective neurotrophin antagonists reveal the close connection of opsin and Trkß. Retinal expression of erythropoietin is under the regulation of HIF1-α, and changes during development. Transduction molecule levels decrease after eye opening, except for photoreceptors. They are synthesized in the cell body, located and transported in the outer segment on common lipid rafts and play a developmental role. Homozygotic mutation of STK38L influences photoreceptor development. Cell death and proliferation are equally present. Hybrid photoreceptors appear that express rod and, to a lesser extent, S-opsin. The degenerated, hybrid mutants retain their capacity to divide. Melatonin is produced at night. Nocturnal light exposition inhibiting hormone production may generate pathological processes (e.g.: carcinomas). The pineal organ in mammals has lost its photoreceptor function and receives information from the retina via sympathetic fibers. Since short wave light inhibits melatonin production, long-wave illumination is recommended during night-shift

Plasminogen Activator Activity in Tears of Pregnant Women

Plasminogen activator activity (PAA) in tears of pregnant women was investigated at various gestation times to assess the availability of plasminogen activator for aiding potential corneal wound healing processes during pregnancy.PAA was measured by a spectrophotometric method. The analysis used 91 tear samples from pregnant and non-pregnant women, supplemented with 10 additional tear PAA measurements from non-pregnant women obtained in a previous study.Tear levels of PAA in pregnant women formed a bimodal distribution. Either the tear PAA level was zero or non-zero during pregnancy. When non-zero, the tear PAA level was dissociated from gestation time and not different than non-pregnant and post-pregnant levels. The frequency of occurrence of zero level tear PAA increased with gestation: 16%, 17% and 46% had zero tear PAA in samples taken from women in the first, second and third trimester, respectively.Overall, of the tear samples taken from women during pregnancy, a total of 26% were at zero tear PAA. The remaining tear samples had non-zero tear PAA values throughout gestation equivalent to non-pregnant tear PAA values, suggesting local control of the source of PAA in tears. Given the importance of the plasminogen activator system in tears to wound healing in the cornea, and the high occurrence of zero tear PAA in our sample of pregnant women, elective corneal surgery would be contraindicated. If corneal surgery is nevertheless necessary, the tear PAA level would be worth checking and patients with low level should be closely observed during the postoperative period

Localization of Caveolin-1 and C-Src in Mature and Differentiating Photoreceptors: Raft Proteins Co-Distribute with Rhodopsin During Development

Numerous biochemical and morphological studies have provided insight into the distribution pattern of caveolin-1 and the presence of membrane rafts in the vertebrate retina. To date however, studies have not addressed the localization profile of raft specific proteins during development. Therefore the purpose of our studies was to follow the localization pattern of caveolin-1, phospho-caveolin-1 and c-src in the developing retina and compare it to that observed in adults. Specific antibodies were used to visualize the distribution of caveolin-1, c-src, a kinase phosphorylating caveolin-1, and phospho-caveolin-1. The labeling pattern of this scaffolded complex was compared to those of rhodopsin and rhodopsin kinase. Samples were analyzed at various time points during postnatal development and compared to adult retinas. The immunocytochemical studies were complemented with immunoblots and immunoprecipitation studies. In the mature retina caveolin-1 and c-src localized mainly to the cell body and IS of photoreceptors, with only very weakly labeled OS. In contrast, phospho-caveolin-1 was only detectable in the OS of photoreceptors. During development we followed the expression and distribution profile of these proteins in a temporal sequence with special attention to the period when OS formation is most robust. Double labeling immunocytochemistry and immunoprecipitation showed rhodopsin to colocalize and co-immunoprecipitate with caveolin-1 and c-src. Individual punctate structures between the outer limiting membrane and the outer plexiform layer were seen at P10 to be labeled by both rhodopsin and caveolin-1 as well as by rhodopsin and c-src, respectively. These studies suggest that membrane raft specific proteins are co-distributed during development, thereby pointing to a role for such complexes in OS formation. In addition, the presence of small punctate structures containing caveolin-1, c-src and rhodopsin raise the possibility that these proteins may transport together to OS during development and that caveolin-1 exists predominantly in a phosphorylated form in the OS. © 2011 Springer Science+Business Media B.V

Adatbiztonság és adatvédelem a mindent átható számítógépes technológia világában = Security and Privacy Issues in Pervasive Computing

(1) Több ugrásos vezeték nélküli hálózatok biztonsága: Ad hoc és szenzorhálózatokban használt útvonalválasztó protokollok biztonágának analízise, új bizonyíthatóan biztonságos protokollok tervezése (enairA, Secure tinyLUNAR). Új támadás-ellenálló adataggregációs algoritmusok tervezése (RANBAR, CORA) és analízise. Spontán kooperáció kialakulása feltételeinek vizsgálata ad hoc és szenzorhálózatokban, kooperáció ösztönzése késleltetéstűrő ad hoc hálózatokban (Barter). (2) Személyes biztonsági tokenek: A nem-megbízható terminál probléma vizsgálata, feltételes aláírásra épülő megoldás tervezése és analízise. (3) RFID biztonsági és adatvédelmi kérdések: Kulcsfa alapú azonosító-rejtő hitelesítés analízise, a privacy szintjének meghatározása. Optimális kulcsfa tervezése. Új azonosító-rejtő hitelesítő protokoll tervezése és összehasonlítása a kulcsfa alapú módszerrel. (4) Formális biztonsági modellek: Szimulációs paradigmára épülő biztonsági modell útvonalválasztó protokollok analízisére. Támadó-modellek és analízis módszer támadás-ellenálló adataggregáció vizsgálatára. Formális modell kidolgozása a korlátozott számítási képességekkel rendelkező humán felhasználó leírására. Privacy metrika kidolgozása azonosító-rejtő hitekesítő protokollok számára. Játékelméleti modellek a spontán koopráció vizsgálatára ad hoc és szenzor hálózatokban, valamint spam és DoS elleni védelmi mechanizmusok analízisére. | (1) Security of multi-hop wireless networks: Security analysis of routing protocols proposed for mobile ad hoc and sensor networks, development of novel routing protocols with provable security (enairA, Secure tinyLUNAR). Development of novel resilient aggregation algorithms for sensor networks (RANBAR, CORA). Analysis of conditions for the emergence of spontaneous cooperation in ad hoc and sensor networks, novel algorithm to foster cooperation in opportunistic ad hoc networks (Barter). (2) Security tokens: Analysis of the untrusted terminal problem, mitigation by using conditional signature based protocols. (3) RFID security and privacy: Analysis of key-tree based private authentication, novel metrics to measure the level of privacy. Design of optimal key-trees, novel private authentication protocols based on group keys. (4) Formal models: Modeling framework for routing protocols based on the simulation paradigm, proof techniques for analyzing the security of routing. Attacker models and analysis techniques for resilient aggregation in sensor networks. Formal model for representing the limited computing capacity of humans. Metrics for determining the level of privacy provided by private authentication protocols. Game theoretic models for studying cooperation in ad hoc and sensor networks, and for analysisng the performance of spam and DoS protection mechanisms

Localization of Caveolin-1 and C-Src in Mature and Differentiating Photoreceptors: Raft Proteins Co-Distribute With Rhodopsin During Development

Numerous biochemical and morphological studies have provided insight into the distribution pattern of caveolin-1 and the presence of membrane rafts in the vertebrate retina. To date however, studies have not addressed the localization profile of raft specific proteins during development. Therefore the purpose of our studies was to follow the localization pattern of caveolin-1, phospho-caveolin-1 and c-src in the developing retina and compare it to that observed in adults. Specific antibodies were used to visualize the distribution of caveolin-1, c-src, a kinase phosphorylating caveolin-1, and phospho-caveolin-1. The labeling pattern of this scaffolded complex was compared to those of rhodopsin and rhodopsin kinase. Samples were analyzed at various time points during postnatal development and compared to adult retinas. The immunocytochemical studies were complemented with immunoblots and immunoprecipitation studies. In the mature retina caveolin-1 and c-src localized mainly to the cell body and IS of photoreceptors, with only very weakly labeled OS. In contrast, phospho-caveolin-1 was only detectable in the OS of photoreceptors. During development we followed the expression and distribution profile of these proteins in a temporal sequence with special attention to the period when OS formation is most robust. Double labeling immunocytochemistry and immunoprecipitation showed rhodopsin to colocalize and co-immunoprecipitate with caveolin-1 and c-src. Individual punctate structures between the outer limiting membrane and the outer plexiform layer were seen at P10 to be labeled by both rhodopsin and caveolin-1 as well as by rhodopsin and c-src, respectively. These studies suggest that membrane raft specific proteins are co-distributed during development, thereby pointing to a role for such complexes in OS formation. In addition, the presence of small punctate structures containing caveolin-1, c-src and rhodopsin raise the possibility that these proteins may transport together to OS during development and that caveolin-1 exists predominantly in a phosphorylated form in the OS. © 2011 Springer Science+Business Media B.V

Impact of aging on calcium influx and potassium channel characteristics of T lymphocytes.

Adaptive immunity and T cell function are affected by aging. Calcium influx patterns, regulated by Kv1.3 and IKCa1 potassium channels, influence T cell activation. We aimed to compare calcium influx kinetics in CD8, Th1 and Th2 cells in human peripheral blood samples obtained from five different age groups (cord blood, 10-15 ys, 25-40 ys, 45-55 ys, 60-75 ys).We measured calcium influx using flow cytometry in samples treated with or without specific inhibitors of Kv1.3 and IKCa1 channels (MGTX and TRAM, respectively).Calcium influx was higher in Th1 cells of adults, however, its extent decreased again with aging. Importantly, these changes were not detected in Th2 cells, where the pattern of calcium influx kinetics is similar throughout all investigated age groups. MGTX had a more pronounced inhibitory effect on calcium influx in Th2 cells, while in Th1 cells the same was true for TRAM in the 25-40 ys and 45-55 ys groups. Calcium influx of CD8 cells were inhibited to a similar extent by both applied inhibitors in these groups, and had no effect in the elderly.Altered lymphocyte potassium channel inhibitory patterns, regulators of calcium influx kinetics, might contribute to the development of age-related changes of T cell function