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J U Prause

Publications and source records attributed to J U Prause.

At least 37 records · Page 2Linked to original sources
PubMed1988

Structure of the vitread face of the monkey optic disc (Macaca mulatta). SEM on frozen resin-cracked optic nerveheads supplemented by TEM and immunohistochemistry.

The authors applied frozen resin cracking after hexamethyldisilazane (HMDS) desiccation on the monkey optic disc region. The cracked face through the central part of the optic disc showed that the inner limiting membrane of the retina continued into the limiting membrane of Elschnig, and this, in turn, continued into the central meniscus of Kuhnt. At the disc margin the membrane was about 70 nm in thickness, due to a large fibrillar component. Elschnig's membrane was about 50 nm in thickness and was composed of both fibrils and flocculent material. The membrane covering the central meniscus of Kuhnt was about 20 nm in thickness. The number of fibrils here was very low, and the membrane consisted of flocculent material. The positive immunohistochemical stainings for GFA and vimentin of Elschnig's membrane and Kuhnt's meniscus were noteworthy. The positive staining disappeared when the membrane continued into the inner limiting membrane of the retina, supporting the different structural composition.

Animals↗
PubMed1988

[Pseudoneuritis pigmentosa in malignant melanoma of the choroid].

In a 65-year-old woman with a choroidal melanoma of the choroid a unilateral pseudoretinitis pigmentosa was detected by ophthalmoscopy. Histological examination revealed a mixed-cell type of malignant melanoma with melanophages and proliferation of pigment epithelium spreading over the inner surface of the retina, with seedings into the vitreous.

Aged↗
PubMed1988

Acanthamoeba keratitis, clinico-pathological report of 2 cases.

Acanthamoebae have in the last 14 years been reported to be responsible for severe keratitis in an increasing number of cases. To our knowledge this is the first report of acanthamoeba keratitis (AK) in Scandinavia. Two young males, both wearing soft contact lenses for extended wear, developed long lasting, therapy resistant keratitis. As the keratitis progressed to risk of perforation, keratoplasty was performed on the clinical, and in the one case biopsy-proven diagnosis of AK. Histopathology on the removed discs demonstrated the presence of typical acanthamoebae in the corneal stroma. The observation period after keratoplasty is at present 5 and 20 months, respectively. Both grafts have remained clear and visual acuity is 6/9-6/12 with glasses.

Acanthamoeba↗
PubMed1988

Predictive value of flow cytometric DNA-analysis on fresh retinoblastoma tissue.

The cellular DNA content and the distribution of tumour cells in different phases of the cell cycles has been analysed in 8 consecutive enucleated eyes with retinoblastoma. All tumours had abnormal ploidy levels. The analysis did not reveal any specific pattern in 2 tumours which had metastasized compared to 6 local tumours. The flow cytometric analysis alone or in combination with histopathology appeared not to improve the classification of large retinoblastomas.

Child, Preschool↗
PubMed1988

Keratoconjunctivitis sicca in patients with primary Sjögren's syndrome. A longitudinal study of ocular parameters.

Thirty-four patients, all fulfilling the Copenhagen criteria for Primary Sjögren's Syndrome, were examined retrospectively in order to evaluate possible longitudinal alterations in Schirmer-1-test results, Rose-bengal score, break-up time and level of ocular score. Twenty-three of the patients were characterized as Bromhexine responders according to their initially positive response to systemic treatment (16 mg x 3 daily) and 11 patients were Bromhexine non-responders. All patients were treated with tear substitutes during the entire observation period of 27 to 76 months (mean 53 months), and all eye examinations were carried out by the same ophthalmologist. The responder group had, both in the start as well as at the end of the observation period, a better ocular status compared to the non-responder group. The latter group had a significantly (P less than 0.02) lower Schirmer-1-test at the start and at the end of the period, and a significantly (P less than 0.02) higher Rose-bengal score at the end of the period. Moreover, the responder group improved in Rose-bengal score (P less than 0.001), whereas the non-responder group improved both in break-up time (P less than 0.05) and Rose-bengal score (P less than 0.05). The use of a score combining results from all three tests, i.e. the ocular score, seems to be a useful tool when evaluating longitudinal variations i dry eye states. Considerable variation was seen between successive results of each ocular test, also in the periods without systemic treatment.

Adult↗
PubMed1988

Light microscopical and scanning electron microscopical examinations of deposits on disposable constant wear lenses.

An inexpensive, disposable soft contact lens for extended wear (DanaLens) has been developed. The lens is polymerized moulded in the wet state from hydroxyethyl methylacrylate and hydroxyethyl acrylate. Twenty-two pairs of the lens have in an open study been worn permanently from 1 to 43 days. Light microscopical and scanning electron microscopical examinations of the used lenses showed: superficial deposits on the front surfaces of the lenses of a mucous-like, easily removable material. Neither bacteria nor fungi were demonstrated.

Adolescent↗
PubMed1988

Isolated leukemic choroidal relapse in a child with acute lymphoblastic leukemia one year off therapy, diagnosed through transvitreal retino-choroidal biopsy.

A serous retinal detachment and choroidal hemorrhagic infiltration developed in a 17-year-old girl with acute lymphoblastic leukemia one year after cessation of therapy without concurrent bone marrow (BM) or central nervous system relapse. A choroidal biopsy through a sclerotomy with simultaneous release of subretinal fluid revealed no malignant cells. Accordingly, she was treated with prednisone, topical corticosteroid and atropine with normalisation of vision and clinical findings. Five months later the retinal detachment and choroidal infiltration recurred. In order to re-attach the retina once more and obtain a representative choroidal biopsy, a pars plana vitrectomy followed by a retinotomy with removal of subretinal tissue was done revealing leukemic infiltration of the choroid. Simultaneously a BM relapse was diagnosed.

Adolescent↗
PubMed1988

Amplification of the human putative oncogene INT1 in primary retinoblastoma tumors.

We report the amplification of the putative oncogene INT1 in two of four retinoblastomas. In one case, the INT1 signal was amplified 10 to 15-fold, in the other 100-fold. In both cases there were signs of increased tumor aggressiveness with invasion of the choroid and development of metastases. The two cases without INT1 amplification had neither metastases nor locally invasive growth. Our findings indicate that INT1 amplification may be a feature of increased malignant potential in retinoblastomas.

Blotting, Southern↗
PubMed1987

Tear fluid electrolytes and albumin in persons under environmental stress.

Sixty-two subjects selected among 287 persons with indoor air complaints were exposed to a standard mixture of 22 different organic gases and vapors normally found in Danish houses. Persons were randomly assigned to one of four exposure groups, and each subject stayed during the test day from 10:00 AM to 4:00 PM under standardized conditions in a climate chamber. During exposure the blink frequency was recorded, and after exposure the tear fluid contents of serum albumin, potassium, and sodium were measured. It was found that the persons had an increased concentration of serum albumin in the tear fluid, and that exposure to high concentrations of organic gases and vapors induced a tear reflex-mediated dilution of the tears.

Adult↗
PubMed1987

Immunohistochemical characterization of intraepidermal in vivo IgG deposits in patients with primary Sjögren's syndrome.

68% of patients with primary Sjögren's syndrome have previously been found to have intra-epidermal in vivo IgG deposits in clinically unaffected skin. In this investigation, we examined immunohistologically skin biopsies from 5 patients with primary Sjögren's syndrome and from 5 normal controls in order to characterize further the intra-epidermal IgG deposits. Employing direct immunofluorescence and peroxidase-antiperoxidase (PAP) techniques, IgG was localized to epidermal cell surfaces. Double-labelling immunofluorescence experiments showed IgG to be bound to OKT6-positive Langerhans cells, and to some degree also to keratinocytes. Only IgG1, IgG3 and in one patient IgA were deposited, whereas IgG2, IgG4, IgM, IgD, IgE, C1q, C3c, C3d, C4, beta-2 microglobulin, albumin, fibrinogen and C-reactive protein were not found deposited in the intra-epidermal area. The epidermal IgG deposits were reactive with anti-Fc-fragment antibodies and with staphylococcal protein-A. These results are compatible with, although not definitive proofs of, the hypothesis that the in vivo deposited IgG is found in the form of IgG-containing immune complexes.

Adult↗
PubMed1987

Characterization of an intraocular retinoblastoma-like tumour.

A transplantable intraocular retinoblastoma-like tumour growing in F 344 rat eyes and tissue cultures suitable for therapeutic experiments is characterized. The tumours grew in the vitreous and infiltrated the internal layers of the retina. Feeder vessels from the retina supplied the tumours. Few and often incomplete rosettes were seen, and calcification was sparse in areas of necrosis. Stainings for glial fibrillary acidic protein, S-100 protein, neuron-specific enolase and desmin were negative. Ultrastructural analysis brought out a close correspondence between the tumour cell and the human retinoblastoma and other virus-induced retinoblastoma-like tumours. The experimental tumour cells lacked cilia, but had neurosecretory granules. Chromosome analysis showed a modal chromosome number in the triploid range, and 6 marker chromosomes were demonstrated. Flow-cytometric analysis showed a S-phase cell fraction of 42%, and chromosome stability was suggested by a tumour-cell DNA index which remained stable for more than 3 months.

Animals↗
PubMed1987

Irreversible immune reactions following keratoplasty. Retrospective clinical and histological evaluation of graft failure in a material of 206 consecutive eyes.

A total of 16/206 eyes in 14/186 patients developed irreversible immune reactions. 15 of the rejected eyes belonged to the 'classical' risk groups, i.e. systemic immune disorders (3/3), metaherpetic keratitis (6/41), pseudophakic bullous keratopathy with inflammation (2/6), non herpetic keratitis with vessel invasion (1/23) and 3 regrafts not included in these groups (a total of 7/31 regrafted eyes rejected). Only 1 rejection occurred in the low-risk groups: an aphakic eye with bullous keratopathy. Histopathological examination revealed that discs which later developed irreversible immune reactions had invariably been grafted in eyes which had vascular invasion and/or inflammation of the recipient cornea. In all, 55/206 eyes ended up with opaque grafts, i.e. irreversible immune reactions were responsible for about one third to one-quarter of the graft failures in the present material. The irreversible immune reactions in the material must be considered 'minimum values', since possible abortive, torpid immune reactions may have escaped recording.

Cornea↗
PubMed1987

Relation between blink frequency and break-up time?

A possible correlation between break-up time (BUT) and blink frequency was investigated in 32 healthy persons (17 females and 15 males) and in 29 patients suffering from primary Sjögren's syndrome (27 females and 2 males). A significant negative correlation, was found between BUT and blink frequency. In persons with high BUT, the blink frequency is low, probably just sufficient to prevent spontaneous tear breaks. In persons with low BUT, i.e. the Sjögren patients, the blink frequency is high, and tear fluid breaks are mostly prevented.

Adult↗
PubMed1987

Trilateral malignant lymphoma: primary malignant B-cell lymphoma of the eyes and brain. Diagnosis by transvitreal retinochoroidal biopsy.

A 59-year-old woman with therapy-resistant bilateral involvement of posterior uvea and retina of some months' duration was examined. Diagnostic vitrectomy was inconclusive, but subsequent transvitreal retinochoroidal biopsy gave ample material for the immunohistopathological diagnosis of a malignant B cell lymphoma. Despite systemic and intrathecal cytostatics and ocular X-ray therapy, central nervous system involvement was observed 2 months later. The ocular lesions regressed after treatment and have not recurred.

B-Lymphocytes↗
PubMed1986

Structure and composition of the inner limiting membrane of the retina. SEM on frozen resin-cracked and enzyme-digested retinas of Macaca mulatta.

After a historical introduction describing previous observations and views on the structure and composition of the internal limiting membrane of the retina (MLI), it is concluded that no definite unifying concept exists concerning the MLI structure. The authors applied frozen resin cracking with hexamethyldisilazane (HMDS) desiccation on normal and enzyme-digested specimens of monkey retinas. Distinct differences were observed between equatorial, macular, and optic disc regions. The MLI in the equatorial and disc regions was about 70 nm thick with an outer dense, basement membranelike part and an inner, loose fibrillar meshwork fusing with the vitreous fibers. The foveal region was 400 nm thick; the dense outer layer was thicker than normal basement membrane, whereas the inner loose meshwork had only a few fibrils. The enzyme-digestion experiments showed that the fibrillar meshwork consisted mainly of collagen fibers surrounded by predominantly hyaluronic acid.

Animals↗
PubMed1986

Hexamethyldisilazane in preparation of retinal tissue for scanning electron microscopy.

A new rapid procedure for desiccating frozen resin-cracked retinal tissue for scanning electron microscopy (SEM) which permits air-drying was found to compare favorably with tissues prepared by critical-point drying: Retinal tissue was fixed in 4% phosphate-buffered neutral formaldehyde, dehydrated by means of graded ethanol, embedded in Epon, cracked and washed in propylene oxide. For desiccation, the specimens were immersed in hexamethyldisilazane (HMDS), air-dried and finally sputter-coated. The method is time-saving, gives extended information in SEM, and the number of good specimens is increased.

Animals↗
PubMed1986

Patients with primary Sjögren's syndrome treated for two months with evening primrose oil.

Twenty-four female and 4 male patients, all fulfilling the Copenhagen criteria for primary Sjögren's syndrome (primary SS), were treated for 8 weeks with evening primrose oil (Efamol). Efamol is a seed oil which consists primarily of the n-6 essential fatty acids (EFA): cis-linoleic acid and gammalinolenic acid (GLA). The investigation was carried out as a randomized, double-blind, placebo-controlled, cross-over trial in order to determine whether long-term treatment of patients with primary SS with Efamol would improve the ocular and oral clinical status, and whether the levels of EFA in plasma and erythrocytes increase during Efamol treatment. The objective ocular status, evaluated by a combined ocular score, including the results from Schirmer-I test, break-up time and van Bijsterveld score, improved significantly during Efamol treatment when compared with Efamol start-values (p less than 0.05), but not when compared with placebo values (p less than 0.2). The GLA metabolite and prostaglandin-E1 (PGE1) precursor dihomogammalinolenic acid (20: 3n6, DGLA) increased both in plasma (p less than 0.001) and in erythrocytes (p less than 0.001) during treatment with Efamol. No correlations between objective ocular and oral status and DGLA values in plasma or erythrocytes were found.

Adult↗