Index

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

Angiogenesis from a new perspective

Angiogenesis is the emergence of new blood and lymph vessels from existing ones. In the pathologic form it contributes to the onset and progression of numerous different human disorders such as cancer, inflammation, atherosclerosis and blinding eye diseases. There exist a number of models to study angiogenesis, both in vitro and in vivo, but there is no single perfect model so far. Consequently there is a need to develop new angiogenesis assays for evaluating blood and lymph vessel behaviour in different physiologic settings. The aim of this thesis was to gain insight into in vivo angiogenesis introducing a new technique in an inflammatory corneal model. The method involved in vivo examination of the cornea and subsequent comparison of in vivo findings with ex vivo immunohistochemical analysis of the same tissue samples. An existing suture model for inflammatory angiogenesis in the cornea was modified for in vivo observations with a clinically-approved corneal confocal microscope. In this thesis, corneal lymph vessels were characterized for the first time in vivo and findings from the experimental bench could be applied in a clinical setting, where presumed lymphatics were observed in a corneal transplant patient with rejection. Furthermore, the technique was extended to investigate time-lapse processes in sprouting and regressing capillaries, and led to a number of new observations. CD11b+ myeloid cells constitute the first bulk of infiltrating inflammatory cells and contribute to inflammatory sprouting and regression in numerous ways including pre-patterning of the corneal stroma and guiding of capillary sprouts. Newly formed hemangiogenic sprouts are perfused with a slow-moving fluid and have a lumen. In blood vessel regression, capillary remodeling occurred by abandonment of sprout tips in close association with macrophages and vascular loops formed by presumed intussusceptive angiogenesis. In addition, a network of pericyte- and endothelium-free basement membrane tubes was formed after desertion or degradation of vascular endothelium in former corneal capillaries. In conclusion, we introduce a new in vivo technique for investigating angiogenesis in a corneal model were in vivo findings can be interpreted with ex vivo definitions of specific cell types by immunohistochemistry. Findings from pre-clinical experiments have been possible to apply in a clinical setting when examining patients with corneal pathology

Transient Anterior Corneal Deposits in a Human Immunodeficiency Virus-Positive Patient

Purpose: To report findings of pigmented anterior corneal deposits in a human immunodeficiency virus-positive patient. Methods: Case report. A 49-year-old human immunodeficiency virus-positive patient was examined after the appearance of pigmented corneal deposits. Slit-lamp biomicroscopy, fundus photography, and laser-scanning in vivo confocal microscopy were performed to visually document the ocular condition. Results: The patient had a history of Mycobacterium avium infection and was suspected to have recovery uveitis from a cytomegalovirus infection. Small, rounded, light brown-colored deposits were distributed across the anterior cornea from limbus to limbus, bilaterally. In vivo confocal microscopy revealed the deposits to be confined to the basal epithelium and Bowman layer, whereas the posterior stroma, Descemet membrane, and the endothelium appeared normal. Systemic steroid treatment was administered, and 2 weeks later, the deposits had vanished on slit-lamp examination, whereas remnants were observed at the microscopic level. Conclusions: The deposits were unusual for their anterior corneal location and pancorneal distribution. The response to systemic steroid treatment remains unexplained and illustrates the complexity of the underlying conditions, their treatment, and the associated pathways of ocular manifestation.Original Publication:Beatrice Bourghardt Peebo, Per Fagerholm and Neil Lagali, Transient Anterior Corneal Deposits in a Human Immunodeficiency Virus-Positive Patient, 2010, CORNEA, (29), 11, 1323-1327.http://dx.doi.org/10.1097/ICO.0b013e3181d07670Copyright: Lippincott Williams & Wilkinshttp://www.lww.com

Transient Anterior Corneal Deposits in a Human Immunodeficiency Virus-Positive Patient

Purpose: To report findings of pigmented anterior corneal deposits in a human immunodeficiency virus-positive patient. Methods: Case report. A 49-year-old human immunodeficiency virus-positive patient was examined after the appearance of pigmented corneal deposits. Slit-lamp biomicroscopy, fundus photography, and laser-scanning in vivo confocal microscopy were performed to visually document the ocular condition. Results: The patient had a history of Mycobacterium avium infection and was suspected to have recovery uveitis from a cytomegalovirus infection. Small, rounded, light brown-colored deposits were distributed across the anterior cornea from limbus to limbus, bilaterally. In vivo confocal microscopy revealed the deposits to be confined to the basal epithelium and Bowman layer, whereas the posterior stroma, Descemet membrane, and the endothelium appeared normal. Systemic steroid treatment was administered, and 2 weeks later, the deposits had vanished on slit-lamp examination, whereas remnants were observed at the microscopic level. Conclusions: The deposits were unusual for their anterior corneal location and pancorneal distribution. The response to systemic steroid treatment remains unexplained and illustrates the complexity of the underlying conditions, their treatment, and the associated pathways of ocular manifestation.Original Publication:Beatrice Bourghardt Peebo, Per Fagerholm and Neil Lagali, Transient Anterior Corneal Deposits in a Human Immunodeficiency Virus-Positive Patient, 2010, CORNEA, (29), 11, 1323-1327.http://dx.doi.org/10.1097/ICO.0b013e3181d07670Copyright: Lippincott Williams & Wilkinshttp://www.lww.com

Informal Social Integration Process of Rohingyas Refugees in Bangladesh

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.Maģistra darba mērķis ir izpētīt Roingijas bēgļu neformālās sociālās integrācijas procesu Bangladešā. Pētījumā lietotas kvalitatīvas pētījuma metodes. Pētījuma dalībnieki ir 20 Roingijas bēgļi kā reģistrētās, tā nereģistrētās bēgļu nometnēs. Pētījumā pievērsta uzmanība arī vietējās kopienas, ekspertu, pilsoniskās sabiedrības un valdības viedokļiem. Kā datu iegūšanas metodes lietotas intervijas, fokusgrupu diskusijas, mutvārdu vēsture un fotoprojekts. Pētījuma teorētisko pamatojumu veido divas teorijas – Karena (Caren, 2005) teorija par neformālo integrācijas procesu un Essera (Esser, 2004) teorija par individuālo asimilāciju. Lietota deskriptīva analīzes pieeja. Lai novērtētu Roingijas bēgļu integrācijas procesu, tiek aplūkotas septiņas sociokultūrālās jomas. Pētījuma rezultāti parāda, ka četrās no septiņām jomām integrācija noris veiksmīgi – sociālo kontaktu, nodarbinātības, valodas un veselības jomās. Trijās no tām – izglītība, politiskā līdzdalība un mājoklis, integrācija ir mazāk veiksmīga. Literatūras analīze un pētījums parāda, ka pirmā hipotēze neapstiprinās, kamēr otrā apstiprinās – Roingijas bēgļi integrējas uzņemošajā sabiedrībā lēni

Hitchhiking in lifestyle trajectories

Bakalaura darba nosaukums ir „Autostops dzīves stila trajektorijās”. Šajā bakalaura darbā autostops tiek aplūkots kā daţādu dzīves stilu sastāvdaļa, kuru piekopj daţādu sociālu grupu pārstāvji. Autostops apskatīts kā viena no dzīves stila trajektorijām dzīves gājumā. Bakalaura darba mērķis ir noskaidrot, kādas dzīves stila pazīmes raksturo pārvietošanos ar autostopiem, kādi faktori motivē šo izvēli un kādu pārmaiľu rezultātā indivīdi izslēdz autostopu no sava dzīves stila. Lai ievāktu empīrisko materiālu, tika izmantotas mutvārdu vēstures intervijas, savukārt datu analīzē izmantotas datos pamatotās teorijas kodēšanas metodes. Iegūtajos rezultātos tika identificēti būtiskākie izvēli stopēt motivējošie faktori, kā arī autostopu raksturojošās dzīves stila pazīmes. Iezīmējās arīdzan daţādas autostopa trajektorijas, kurās identificējami noteikti pagrieziena punkti, kas veicinājuši autostopa pārtraukšanu. Atklājās arī, kā daţādas pārmaiľas reizēm tiek saskaľotas ar autostopu. Atslēgas vārdi: autostops, stopēšana, dzīves stils, dzīves gājums, trajektorijas, pagrieziena punkti, mutvārdu vēsture.The name of the bachelor thesis is „Hitchhiking in lifestyle trajectories”. 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

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

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

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

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