| 1. |
- Oohashi, T, et al.
(author)
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Mouse ten-m/Odz is a new family of dimeric type II transmembrane proteins expressed in many tissues
- 1999
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In: Journal of Cell Biology. - 0021-9525. ; 145:3, s. 563-577
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Journal article (peer-reviewed)abstract
- The Drosophila gene ten-m/odz is the only pair rule gene identified to date which is not a transcription factor. In an attempt to analyze the structure and the function of ten-m/odz in mouse, we isolated four murine ten-m cDNAs which code for proteins of 2,700-2, 800 amino acids. All four proteins (Ten-m1-4) lack signal peptides at the NH2 terminus, but contain a short hydrophobic domain characteristic of transmembrane proteins, 300-400 amino acids after the NH2 terminus. About 200 amino acids COOH-terminal to this hydrophobic region are eight consecutive EGF-like domains. Cell transfection, biochemical, and electronmicroscopic studies suggest that Ten-m1 is a dimeric type II transmembrane protein. Expression of fusion proteins composed of the NH2-terminal and hydrophobic domain of ten-m1 attached to the alkaline phosphatase reporter gene resulted in membrane-associated staining of the alkaline phosphatase. Electronmicroscopic and electrophoretic analysis of a secreted form of the extracellular domain of Ten-m1 showed that Ten-m1 is a disulfide-linked dimer and that the dimerization is mediated by EGF-like modules 2 and 5 which contain an odd number of cysteines. Northern blot and immunohistochemical analyses revealed widespread expression of mouse ten-m genes, with most prominent expression in brain. All four ten-m genes can be expressed in variously spliced mRNA isoforms. The extracellular domain of Ten-m1 fused to an alkaline phosphatase reporter bound to specific regions in many tissues which were partially overlapping with the Ten-m1 immunostaining. Far Western assays and electronmicroscopy demonstrated that Ten-m1 can bind to itself.
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| 2. |
- Frisén, Lars, 1939, et al.
(author)
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Surgically created fourth-third cranial nerve communication: temporary success in a child with bilateral third nerve hamartomas. Case report.
- 1999
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In: Journal of neurosurgery. - : Journal of Neurosurgery Publishing Group (JNSPG). - 0022-3085. ; 90:3, s. 542-5
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Journal article (peer-reviewed)abstract
- Shortly after birth, an otherwise healthy infant developed eye deviation and ptosis due to a hamartomatous lesion of the interpeduncular segment of the right oculomotor nerve. The left nerve became similarly involved when the child was 1.5 years of age. Direct nerve repair was not possible. Instead, the trochlear nerve was divided and its proximal end was attached to the distal end of the third nerve. Elevation of the upper eyelid and partial adduction of the eye developed gradually over the ensuing 3 to 5 months. Both functions were lost after an additional 2 months, presumably as a result of tumor recurrence or neuroma formation. This case report shows that surgically created fourth-third cranial nerve communication is feasible and may merit consideration under similar circumstances.
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| 3. |
- Abrahamsson, Maths, 1953, et al.
(author)
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The occurrence of congenital cataract in western Sweden
- 1999
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In: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907. ; 77:5, s. 578-580
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Journal article (peer-reviewed)abstract
- Purpose: To estimate the occurrence of congenital cataract in a Nordic country. Methods: In 1980, we constructed a database in the Department of Ophthalmology Goteborg University, containing basic data from all cases in western Sweden diagnosed with congenital cataract. By collecting and processing these data from 1980 onwards, we hoped to improve the management of congenital cataract treatment and to optimize the outcome of the treatment. Results: In this study, the incidence of congenital cataract in the four western counties of Sweden was evaluated. The occurrence rate of all cases with congenital cataract during the study period was 36 cases per 100 000. The occurrence rate for dense bilateral and all unilateral cases were both 14 per 100 000 each. Conclusion: There were no time-related changes in incidence of congenital cataract from 1980 until today, although there was a large variation in the yearly incidence.
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| 4. |
- Bengtsson, Boel
(author)
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Improved computerized perimetric threshold strategies
- 1999
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Doctoral thesis (other academic/artistic)abstract
- Perimetric threshold examination is the most important method for diagnosing and monitoring patients with glaucoma. Such examination, however, is time-consuming and often difficult for the elderly patients in whom glaucoma is prevalent. Shorter test strategies have been proposed, but unfortunately also with lower test quality. By using new computer-intense techniques for acquisition and processing of test data it was possible to reduce test time of perimetric threshold tests without decreasing quality in test results. The new SITA strategies were developed using such techniques to yield the same accuracy in test results as today’s traditional test strategies, the Humphrey Full Threshold and Fastpac strategies, while considerably reducing test time. Most development was performed using computer simulations. The SITA strategies were evaluated in comparison with traditional strategies in real-time measurements in both normal subjects and glaucoma patients. Test time was reduced by nearly 50% and reproducibility was at least as good as with the conventional strategies. Age normal sensitivity values were higher, and normal limits were narrower, i.e., in SITA fields shallower defects are needed to be recognized as significant loss. Both SITA strategies showed at least as good sensitivity and specificity as the Humphrey Full Threshold strategy when interpreting test results relative to age normal values and normal limits.
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| 5. |
- Ghosh, Fredrik
(author)
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Experimental Neuroretinal Transplantation
- 1999
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Doctoral thesis (other academic/artistic)abstract
- Embryonic full-thickness rabbit neuroretinal sheets were transplanted to the subretinal space of adult hosts. This was accomplished by using a new transplantation technique involving vitrectomy and retinotomy. The grafts were followed from 10 to 306 days after surgery, and were then examined by different histological techniques. In the light microscope, the transplants were seen to develop the normal retinal lamination and fused with the host retina, especially after long survival times. Ultrastructurally, normal photoreceptor outer segments, well integrated with the host retinal pigment epithelium were found. Growth cones were present in the zone of fusion between graft and host retina. Immunohistochemical labeling revealed many of the normal retinal components not previously found in retinal transplants, and graft-host connections between neurons in the rod pathway were seen. The morphology of vibratome sectioned neuroretinal sheets as well as adult full-thickness grafts was also examined. These transplantation types showed less of the normal morphology compared with embryonic full-thickness grafts. The immunogenicity of embryonic full-thickness and fragmented grafts was compared using Major Histocompatibility Complex (MHC) immunolabeling. Fragmented grafts elicited a response from the host immune system similar to a chronic transplant rejection. This reaction was absent in the full-thickness grafts which is in accordance with their good long-term survival.
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| 6. |
- Ghosh, F, et al.
(author)
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Graft-host connections in long-term full-thickness embryonic rabbit retinal transplants
- 1999
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In: Investigative Ophthalmology and Visual Science. - 0146-0404. ; 40:1, s. 32-126
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Journal article (peer-reviewed)abstract
- PURPOSE: To establish neuronal connections in the rod and cone pathway between laminated rabbit retinal transplants and the host retina.METHODS: Fourteen adult rabbits received a complete full-thickness embryonic transplant. After survival times of 3 to 10 months, the retinas were studied under light microscope and with immunohistochemistry. Antibodies against protein kinase C (PKC), parvalbumin, and calbindin were used to label rod bipolar cells, AII amacrine cells, and cone bipolar cells, respectively. The AB5 antibody was used to label ganglion cells.RESULTS: The transplants displayed laminated morphology with layers parallel to the host retinal pigment epithelium. In the oldest specimens (10 months after surgery), laminated layers of graft and host approached each other and almost reconstructed the normal retinal appearance. The ganglion and cone bipolar cells of the host survived well, as was seen with AB5 and calbindin double-labeling. Connections between cone bipolar cells in the graft and ganglion cells in the host were not common. PKC-labeled rod bipolar cells and parvalbumin-labeled AII amacrine cells of host and graft showed sprouting activity directed toward an intermediate plexiform layer located between the graft and host. In specimens double-labeled with PKC and parvalbumin, this intermediate plexiform layer was seen to contain numerous PKC- and parvalbumin-labeled processes. Direct connections between rod bipolar and AII amacrine cells in host and graft were seen in the 10-month specimens.CONCLUSIONS: Full-thickness embryonic transplants survive for at least 10 months, and normal laminated morphology develops. Host and graft fuse and together contribute nerve cell processes to an intermediate plexiform layer. Direct graft-host contacts are also present between neuronal types that in the normal retina participate in the rod pathway.
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| 7. |
- Ghosh, F, et al.
(author)
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Immunohistochemical markers in full-thickness embryonic rabbit retinal transplants
- 1999
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In: Ophthalmic Research. - : S. Karger AG. - 0030-3747 .- 1423-0259. ; 31:1, s. 5-15
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Journal article (peer-reviewed)abstract
- PURPOSE: To examine immunohistochemical markers in straight, well-laminated retinal transplants with special attention paid to the interphotoreceptor matrix, the Müller cells and the ganglion cells as these three retinal components have been abnormal in transplants produced by previous methods.METHODS: Nine rabbits underwent subretinal transplantation of a complete full-thickness embryonic neuroretina. After 31 or 49 days, the transplants were stained for light microscopy and processed for immunohistochemistry.RESULTS: Six of 9 eyes contained transplants with straight, well-laminated regions with all light-microscopic characteristics of a normal retina. In the outer segment region, the expression of peanut agglutinin showed segmental labeling of cone domains in the interphotoreceptor matrix, and interphotoreceptor retinoid binding protein immunoreactivity was found. Glial fibrillary acidic protein and vimentin immunoreactivity revealed normal Müller cell morphology. In 3 transplants the AB5-antibody-labeled ganglion cells in the ganglion cell layer and all transplants contained nerve fibers in the nerve fiber layer labeled by an antibody against neurofilament of 160 kD. The latter also labeled fibers connecting the transplant with the host.CONCLUSIONS: Full-thickness embryonic retinal transplants develop the normal retinal appearance and display several of the retinal components necessary for normal function which are not found in transplants produced by previous methods.
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| 8. |
- Ghosh, F, et al.
(author)
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Long-term full-thickness embryonic rabbit retinal transplants
- 1999
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In: Investigative Ophthalmology and Visual Science. - 0146-0404. ; 40:1, s. 42-133
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Journal article (peer-reviewed)abstract
- PURPOSE: To establish the light and electron microscopic morphology of long-term full-thickness embryonic rabbit retinal transplants, with special attention paid to graft- host integration.METHODS: Eighteen rabbits received a complete embryonic neuroretina 19 days after conception. The transplants were positioned under the host retina, flat against the host retinal pigment epithelium with proper polarity, using a vitrectomy technique. After surviving 3 to 10 months, the transplants were examined by light and electron microscopy.RESULTS: The outer retina of the host had degenerated in all specimens. In 16 of the 18 eyes, well-laminated transplants with correct polarity, measuring up to 3.2 mm in length, were found. The transplants displayed long outer segments facing the host retinal pigment epithelium, and they were laminated to the level of the inner plexiform layer in which fusion with the host was often evident. Fusion was more prominent in the oldest transplants. Electron microscopy revealed bundles of neurites at different levels of maturation in close contact with Müller cell fimbriae at regular intervals along the graft-host border.CONCLUSIONS: Full-thickness embryonic rabbit retinal transplants positioned with correct polarity develop into large laminated retinas and survive without immunosuppression for at least 10 months. Host and graft adapt and almost reconstruct the normal retinal appearance. Ultrastructurally, well-developed photoreceptors and many normal synapse types are seen, and neuron sprouting is evident at the graft-host border.
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| 9. |
- Ghosh, F, et al.
(author)
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Partial and full-thickness neuroretinal transplants
- 1999
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In: Experimental Eye Research. - : Elsevier BV. - 0014-4835. ; 68:1, s. 67-74
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Journal article (peer-reviewed)abstract
- Adult and embryonic rabbit retinal sheets were transplanted into the subretinal space of adult rabbits. The transplants were either full-thickness with intact layering, or gelatin embedded and vibratome sectioned with the inner retina removed. The full-thickness grafts were positioned subretinally by means of a glass capillary in which they were partially folded. The vibratome sectioned ones were placed using a plastic injector in which the gelatin embedded graft was flat. The embryonic full-thickness grafts were followed clinically up to 3 months, and the other 3 transplant types up to 1 month postoperatively, after which the retina was sectioned and stained for light microscopy. Surgical complications were more common in eyes receiving vibratome sectioned grafts with 10 out of 34 eyes displaying blood in the vitreous. Four of these eyes also developed total retinal detachment. Out of 17 eyes receiving full-thickness grafts, only one displayed these complications. Histologically, 11 out of 13 embryonic full-thickness transplants revealed straight, laminated transplants with correct polarity, and with all normal retinal layers present. In these transplants, fusion with the host increased in time. Of the adult full-thickness transplants, only 1 out of 4 survived, and this graft showed signs of degeneration. The vibratome sectioned adult transplants in a few cases survived the first two postoperative weeks. In these grafts, both inner and outer retina were present, indicating an incomplete vibratome sectioning. With longer postoperative times, the number of surviving transplants in this group diminished considerably. All vibratome sectioned embryonic transplants developed into rosettes and sometimes also into laminated sections with reversed polarity. It can be concluded that in rabbits, the surgical technique used for vibratome sectioned transplants requires a larger sclerotomy and retinotomy, since they have to be kept flat in the transplanting instrument due to the surrounding gelatin. This technique is associated with a higher frequency of complications than the one used for full-thickness grafts which are more flexible and can be transplanted with a smaller instrument. Vibratome sectioning of embryonic grafts results in abnormal morphology and their adult counterparts only survive if the sectioning is incomplete. Adult full-thickness grafts show poor survival. Embryonic full-thickness transplants in the majority of cases develop into laminated retinas with layers parallel to the host retinal pigment epithelium. They also survive and integrate well with the host retina.
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| 10. |
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