Age-Related Absorption of the Human Lens in the Near-Ultraviolet Range.

The purpose of the present study was to determine the age dependence of the ultraviolet (UV) absorption of the different parts of the human crystalline lens. Cryostat sections of human cadaveric lenses (60 µm) were cut. The UV absorbance of nine samples, derived from different parts of the lens, was determined using a Shimadzu scanning spectrophotometer. The absorbance of the anterior and posterior lens capsules was measured separately. The absorption coefficients were calculated from the measured absorbance and values taken at 280 as well as at 360 nm were compared statistically. ANCOVA analysis of the values taken at 280 and at 360 nm wavelengths shows that correlation between the absorption coefficients and age can be found only in the case of the posterior layers. These results suggest a differential age-dependent increase of the UV absorption of the posterior layers compared to the anterior ones and can be related to the differential protein expression in the anterior and posterior parts. Posterior crystalline lens capsules have higher absorption coefficients than the anterior ones regardless of age.

The molecular background of the differential UV absorbance of the human lens in the 240-400 nm range.

The ultraviolet (UV) absorption of various sections of the human lens was studied and compared with protein expression paralleling differential UV absorbance in anterior and posterior lenticular tissue. The UV absorbance of serial lens cryostat sections (60 µm) and that of lens capsules was determined using a Shimadzu scanning spectrophotometer, and the absorption coefficients were calculated. Two-dimensional gel electrophoresis was performed using two pooled lenticular protein extracts (anterior and posterior sections). Protein spots were quantified and significantly different spots were identified by mass spectrometry following in-gel digestion with trypsin and chymotrypsin. The UV-C and UV-B absorption of the human lens increased toward the posterior parts of the lens. The anterior and posterior lens capsules also effectively absorbed UV radiation. Levels of molecular chaperone proteins Beta-crystallin B2 (UniProtKB ID:P43320), A3 (UniProtKB ID:P05813) and of glyceraldehyde 3-phosphate dehydrogenase (UniProtKB ID:P04406) were significantly higher in the anterior part of the lens, whereas lens proteins Beta-crystallin B1 (UniProtKB ID:P53674) and Alpha-crystallin A chain (UniProtKB ID:P02489) were higher in the posterior sections. These results provide evidence that differential UV absorption in the anterior and posterior lens is accompanied by differential protein expression.

Role of ultrasound biomicroscopy in diagnosis and treatment of Terrien disease.

PURPOSE: Terrien disease is a rare form of peripheral corneal degeneration characterized by vascularization, opacification, lipid deposition, and corneal thinning. In this study, a high-frequency ultrasound biomicroscope (UBM) was used to detect the morphologic changes before and after surgery and to determine the stages of this disease. METHODS: Two patients with Terrien disease were examined by UBM, corneal topography, and a keratometer before and after surgery (full-thickness keratectomy). RESULTS: The absence of the Bowman layer and thinning of the Descemet layer in the ectatic part of the peripheral cornea were detected by using the UBM before surgery. Earlier, these signs could be detected only with optical and electron microscopy from histologic samples; now we can detect the signs of Terrien disease with noninvasive devices such as the UBM. CONCLUSIONS: The UBM is an effective device for following the progression of Terrien disease and determining the timing of these patients' surgeries.

Photorefractive keratectomy in megalophthalmos anterior.

PURPOSE: To evaluate the results of photorefractive keratectomy (PRK) for the correction of myopia and myopic astigmatism in megalophthalmos anterior. METHODS: Four eyes of two brothers with megalophthalmos anterior were treated with PRK. In patient 1, best spectacle-corrected visual acuity (BSCVA) was 20/20 in both eyes with a refraction of -4.50 -4.50 x 180 degrees in the right eye and -3.75 -3.00 x 175 degrees in the left eye. In patient 2, BSCVA was 20/25 in both eyes with a refraction of -4.25 x 166 degrees in the right eye and +0.50 -4.00 x 175 degrees in the left eye. RESULTS: Topographic map, slit-lamp, ultrasound biomicroscopy, and postoperative course (no progression), supported with vectorial analysis, demonstrated megalophthalmos anterior. During 24-month follow-up, mild haze was observed and BSCVA was maintained. CONCLUSIONS: Myopia and astigmatism are often observed in this type of nonprogressive corneal dysgenesis. Based on this fact and our results, we recommend PRK in cases of megalophthalmos anterior.

Erdheim-Chester's disease of the heart: a diagnostic conundrum and collision with the same mass in the orbit.

Erdheim-Chester's disease is a rare multisystem xanthogranulomatosis, afflicting the skeletal system with the occasional involvement of soft tissues. We delineate an unusual case of a cardiac variant of Erdheim-Chester's disease presenting with pericardial effusion and as a collision with a synchronous orbital manifestation. We describe our diagnostic pathway and propose a novel treatment option involving nonsteroidal anti-inflammatory drugs. The role of cyclo-oxygenase in the disease process and inhibition thereof by NSAIDs is hypothesized and discussed.

[Ultrasound biomicroscopy examination of tumors of the iris and ciliary body]. / Az iris és a corpus ciliare térfoglaló folyamatainak ultrahangbiomikroszkópos vizsgálata.

The ultrasound biomicroscope (UBM) has a major role in detecting and following different types of intra-ocular masses in the anterior part of the eye. This equipment may provide the possibility to detect the inner structure of the masses, to differentiate between cysts and solid tumours, and to follow their progression and spreading into the surrounding tissue. In the last six years 30 patients with iris and ciliary body tumour were found in our laboratory. The examination were performed by Zeiss Humphrey Ultrasound Biomicroscope, Model 840, 50 MHz probe. We followed closely 22 patients. Surgical removal and histological examination were performed in 3 cases. Melanocytoma, retinoblastoma and ring melanoma were revealed. Although the symptoms of the anterior uveal tumours are uncommon, and these tumours show very slow progression, early detection and regular follow-up is needed. In the case of tumour progression the UBM has an important role in planning and timing of surgery or radiotherapy, which can have a favourable effect on the outcome of the disease.

Survival and proliferative ability of various living cell types after laser-induced forward transfer.

The survival, proliferation, and differentiation of freshly isolated and cultured cells were studied after absorbing film-assisted laser-induced forward transfer. Rat Schwann and astroglial cells and pig lens epithelial cells were used for transfer and the cells were cultured for 2 weeks after laser-pulsed transfer. All three cell types survived, proliferated, and differentiated under cell culture conditions and regained their original phenotype a few days after cell transfer. Time resolution studies have shown that the time required to accelerate the jets and droplets containing the cells was less than 1 micros and that the estimated minimum average acceleration of those ejected cells that reached a constant velocity was approximately 10(7) x g. This suggests that the majority of studied cells tolerated the extremely high acceleration at the beginning of the ejection and the deceleration during impact on the acceptor plate without significant damage to the original phenotype. These results suggest that the absorbing film-assisted laser-induced forward transfer technique appears to be suitable for several potential applications in tissue engineering and the biomedical tissue repair technologies.

UV absorbance of the human cornea in the 240- to 400-nm range.

PURPOSE: To determine the UV absorbance of the corneal layers (epithelium, Bowman layer, stroma) in the 240- to 400-nm range. METHODS: Consecutive slices (100 microm) of human cadaveric corneas were cut, and the UV absorbance of each sample was determined in a scanning spectrophotometer. In some cases the epithelium was scraped off and its absorbance measured separately. RESULTS: The investigation of the UV-B absorption of consecutive corneal slices revealed evidence that UV-B absorption is 1.8 times higher in the anterior 100 microm of the human cornea than in the posterior layers. The UV absorbance of the posterior layers was uniform, showing no further structural dependence. The epithelium and Bowman layer are both effective absorbers of UV-B radiation. CONCLUSIONS: These results suggest that the anterior corneal layers are particularly important in preventing damage by UV-B radiation.