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    PURPOSE. To determine whether in vivo confocal microscopy (IVCM) of the cornea can be used for the label-free detection and monitoring of lymph vessels in live corneas. METHODS. Parallel corneal hemangiogenesis and lymphangiogenesis was induced by the placement of a single suture in one cornea of male Wistar rats. Fourteen days after suture placement and under general anesthesia, laser-scanning IVCM was performed in the vascularized region. Corneas were subsequently excised for flat-mount double immunofluorescence with a pan-endothelial marker (PECAM-1/CD31) and a lymphatic endothelial specific marker (LYVE-1). Using the suture area and prominent blood vessels as points of reference, the identical microscopic region was located in both fluorescent and archived in vivo images. Additionally, vessel diameter, lumen contrast, and cell diameter and velocity within vessels were quantified from in vivo images. RESULTS. Comparison of identical corneal regions in fluorescence and in vivo revealed prominent CD31(+)/LYVE-1(3+) lymph vessels that were visible in vivo. In vivo, corneal lymph vessels were located in the vascularized area in the same focal plane as blood vessels but had a darker lumen (P andlt; 0.001) sparsely populated by highly reflective cells with diameters similar to those of leukocytes in blood vessels (P = 0.61). Cell velocity in lymph vessels was significantly reduced compared with blood particle velocity (P andlt; 0.001). Morphologic characteristics enabled subsequent identification of corneal lymphatics in live, vascularized rat corneas before immunofluorescence labeling. CONCLUSIONS. IVCM enabled the nondestructive, label-free, in vivo detection of corneal lymphatics. IVCM provides the possibility of observing lymphatic activity in the same live corneas longitudinally and, as a clinical instrument, of monitoring corneal lymphatics in live human subjects

    Cellular level characterization of capillary regression in inflammatory angiogenesis using an in vivo corneal model

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    In this study, we introduce a technique for repeated, microscopic observation of single regressing capillaries in vivo in inflamed murine corneas. Natural capillary regression was initiated by removal of inflammatory stimulus during an active pro-angiogenic phase, while the additional impact of anti-angiogenic treatment with triamcinolone or bevazicumab was investigated. Capillaries regressed naturally within 1 week and treatments did not further enhance the natural regression. Morphologically, early-phase regression was characterized by significant lumen narrowing and a significant reduction in CD11b+ myeloid cell infiltration of the extracellular matrix. By 1 week, vascular remodeling occurred concomitant with CD11b+CD68+KiM2R+ mature macrophage localization on capillary walls. Empty conduits without blood flow, positive for collagen IV and devoid of vascular endothelium and pericytes, were apparent in vivo and by 3 weeks were more numerous than perfused capillaries. By 3 weeks, macrophages aggregated around remaining perfused capillaries and were observed in apposition with degrading capillary segments. Abrupt termination of capillary sprouting in our regression model further revealed vascular endothelial abandonment of sprout tips and perfused capillary loop formation within a single angiogenic sprout, possibly as an intussusceptive response to cessation of the stimulus. Finally, we observed lumen constriction and macrophage localization on capillary walls in vivo in a clinical case of corneal capillary regression that paralleled findings in our murine model.The original publication is available at www.springerlink.com: Beatrice Bourghardt Peebo, Per Fagerholm, Catharina Traneus-Rockert and Neil Lagali, Cellular level characterization of capillary regression in inflammatory angiogenesis using an in vivo corneal model, 2011, Angiogenesis, (14), 3, 393-405. http://dx.doi.org/10.1007/s10456-011-9223-3 Copyright: Springer Verlag (Germany) http://www.springerlink.com

    Time-Lapse In Vivo Imaging of Corneal Angiogenesis: The Role of Inflammatory Cells in Capillary Sprouting

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    PURPOSE. To elucidate the temporal sequence of events leading to new capillary sprouting in inflammatory corneal angiogenesis. METHODS. Angiogenesis was induced by corneal suture placement in Wistar rats. The inflamed region was examined by time-lapse in vivo confocal microscopy for up to 7 days. At 6 and 12 hours and 1, 2, 4, and 7 days, corneas were excised for flat mount immunofluorescence with primary antibodies for CD31, CD34, CD45, CD11b, CD11c, Ki-M2R, NG2, and alpha-SMA. From days 0 to 4, the in vivo extravasation and expansion characteristics of single limbal vessels were quantified. RESULTS. Starting hours after induction and peaking at day 1, CD45(+)CD11b(+) myeloid cells extravasated from limbal vessels and formed endothelium-free tunnels within the stroma en route to the inflammatory stimulus. Limbal vessel diameter tripled on days 2 to 3 as vascular buds emerged and transformed into perfused capillary sprouts less than 1 day later. A subset of spindle-shaped CD11b(+) myeloid-lineage cells, but not dendritic cells or mature macrophages, appeared to directly facilitate further capillary sprout growth. These cells incorporated into vascular endothelium near the sprout tip, co-expressing endothelial marker CD31. Sprouts had perfusion characteristics distinct from feeder vessels and many sprout tips were open-ended. CONCLUSIONS. Time-lapse in vivo corneal confocal microscopy can be used to track a temporal sequence of events in corneal angiogenesis. The technique has revealed potential roles for myeloid cells in promoting vessel sprouting in an inflammatory corneal setting.Original Publication: Beatrice Bourghardt Peebo, Per Fagerholm, Catharina Traneus-Rockert and Neil Lagali, Time-Lapse In Vivo Imaging of Corneal Angiogenesis: The Role of Inflammatory Cells in Capillary Sprouting, 2011, INVESTIGATIVE OPHTHALMOLOGY and VISUAL SCIENCE, (52), 6, 3060-3068. http://dx.doi.org/10.1167/iovs.10-6101 Copyright: Research in Vision and Opthalmology http://www.arvo.org

    Hitchhiking in lifestyle trajectories

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    Bakalaura darba nosaukums ir ā€žAutostops dzÄ«ves stila trajektorijāsā€. Å ajā bakalaura darbā autostops tiek aplÅ«kots kā daţādu dzÄ«ves stilu sastāvdaļa, kuru piekopj daţādu sociālu grupu pārstāvji. Autostops apskatÄ«ts kā viena no dzÄ«ves stila trajektorijām dzÄ«ves gājumā. Bakalaura darba mērÄ·is ir noskaidrot, kādas dzÄ«ves stila pazÄ«mes raksturo pārvietoÅ”anos ar autostopiem, kādi faktori motivē Å”o izvēli un kādu pārmaiľu rezultātā indivÄ«di izslēdz autostopu no sava dzÄ«ves stila. Lai ievāktu empÄ«risko materiālu, tika izmantotas mutvārdu vēstures intervijas, savukārt datu analÄ«zē izmantotas datos pamatotās teorijas kodÄ“Å”anas metodes. IegÅ«tajos rezultātos tika identificēti bÅ«tiskākie izvēli stopēt motivējoÅ”ie faktori, kā arÄ« autostopu raksturojoŔās dzÄ«ves stila pazÄ«mes. IezÄ«mējās arÄ«dzan daţādas autostopa trajektorijas, kurās identificējami noteikti pagrieziena punkti, kas veicinājuÅ”i autostopa pārtraukÅ”anu. Atklājās arÄ«, kā daţādas pārmaiľas reizēm tiek saskaľotas ar autostopu. Atslēgas vārdi: autostops, stopÄ“Å”ana, dzÄ«ves stils, dzÄ«ves gājums, trajektorijas, pagrieziena punkti, mutvārdu vēsture.The name of the bachelor thesis is ā€žHitchhiking in lifestyle trajectoriesā€. In this bachelor thesis autostop is examined as a part of different lifestyles, which is practiced by representatives of different social groups. Autostop is viewed as one of life long lifestyle trajectories. Objective of the bachelor thesis is to determine, which lifestyle signs are characterized by using autostop, which factors motivate this choice, and which changes can result in excluding autostop from ones lifestyle. Oral history interviews were used to gain experiential material, however grounded theory coding methods are used for data analysis. The key factors for motivating the choice to autostop were identified in the obtained results, as well as characteristic lifestyle signs of autostop. Also different autostop trajectories were marked, in which certain turning points can be identified, that have contributed to discontinuation of autostop. Information on how different changes can occasionally be coordinated with autostop were revealed, too. Key words: autostop, hitchhiking, lifestyle, life course, trajectories, turning points, oral history

    Informal Social Integration Process of Rohingyas Refugees in Bangladesh

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    The purpose of this study is to examine the informal social integration process of Rohingyas refugees in Bangladesh. This is the qualitative study. The sample presented here 20 Rohingyas refugees in both registered and unregistered refugee camps as well as the opinion of the local community, experts, civil society and the government. Data are obtained through in-depth interviews, focus group discussions, oral history and photo projects. There are two theories followed for this study; one is Carens (2005) informal integration process and another is Essers (2004) individual assimilation. The descriptive approach is followed to write the analysis. Moreover, the seven socio-cultural domains are examined to measure the integration process of Rohingyas refugees in Bangladesh. Out of seven domains, four get the success of integration. Those domains are social contact, employment, language and health. On the other hand, three other domains indicate less success than the previous four. Those three domains are education, political participation and housing. Therefore, the literature and the fieldwork revels the failure of first hypothesis whereas the second hypothesis is accepted that the Rohingyas refugees have been integrating to the host society slowly.MaÄ£istra darba mērÄ·is ir izpētÄ«t Roingijas bēgļu neformālās sociālās integrācijas procesu BangladeŔā. PētÄ«jumā lietotas kvalitatÄ«vas pētÄ«juma metodes. PētÄ«juma dalÄ«bnieki ir 20 Roingijas bēgļi kā reÄ£istrētās, tā nereÄ£istrētās bēgļu nometnēs. PētÄ«jumā pievērsta uzmanÄ«ba arÄ« vietējās kopienas, ekspertu, pilsoniskās sabiedrÄ«bas un valdÄ«bas viedokļiem. Kā datu iegÅ«Å”anas metodes lietotas intervijas, fokusgrupu diskusijas, mutvārdu vēsture un fotoprojekts. PētÄ«juma teorētisko pamatojumu veido divas teorijas ā€“ Karena (Caren, 2005) teorija par neformālo integrācijas procesu un Essera (Esser, 2004) teorija par individuālo asimilāciju. Lietota deskriptÄ«va analÄ«zes pieeja. Lai novērtētu Roingijas bēgļu integrācijas procesu, tiek aplÅ«kotas septiņas sociokultÅ«rālās jomas. PētÄ«juma rezultāti parāda, ka četrās no septiņām jomām integrācija noris veiksmÄ«gi ā€“ sociālo kontaktu, nodarbinātÄ«bas, valodas un veselÄ«bas jomās. Trijās no tām ā€“ izglÄ«tÄ«ba, politiskā lÄ«dzdalÄ«ba un mājoklis, integrācija ir mazāk veiksmÄ«ga. LiteratÅ«ras analÄ«ze un pētÄ«jums parāda, ka pirmā hipotēze neapstiprinās, kamēr otrā apstiprinās ā€“ Roingijas bēgļi integrējas uzņemoÅ”ajā sabiedrÄ«bā lēni
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