Inhibitory Effects of Imatinib Mesylate on Transdifferentiation of Lens Epithelial Cells into Fibroblast

PURPOSE: To investigate whether Imatinib mesylate (IM) could inhibit the transdifferentiation of the lens epithelial cells (LECs) into fibroblasts using the capsular bag model. METHODS: In the capsular bag model, LECs were cultured by exposure to IM at various concentrations for 3 min. The effect of IM was analysed by observing the covering area, numbers of alpha-SMA positive cell, and BrdU incorporated proliferating cells. The same analysis was performed in the culture of LECs with TGF-beta. RESULTS: The covering area was significantly decreased by the treatment of 30 micro M IM, and the positive cells for alpha-SMA and BrdU were also decreased by IM treatment in a dose dependent manner. In addition, increasing TGF-beta concentration accelerated transdifferentiation, but suppressed the acceleration of the transdifferentiation induced by TGF-beta. CONCLUSIONS: In the capsular bag model, IM effectively inhibited not only the transdifferentiation of LECs into fibroblasts but also the TGF-beta induced acceleration of the transdifferentiation.

Differentiation and Transdifferentiation of Lens Epithelial Cells in Capsular Bag Model Culture

PURPOSE: To investigate the differentiation of lens epithelial cells (LECs) to lens fiber, and the transdifferentiation of LECs to fibroblast in capsular bag culture. METHODS: After observing the changes of LECs by using phase-contrast microscopy, we observed a cross section of capsular bag by using light microscope (LM) and electron microscope (EM). In addition, the expressions of alpha A-crystallin, a marker of differentiation of LEC to lens fiber, and of alpha-smooth muscle actin, a marker of LEC to fibroblast, were examined during the culture period by western blot. RESULTS: On phase-contrast microscopy, 7 to 14 days after culture, the portion of LECs was gradually elongated and cytoplasm became transparent, so that the differentiation resembled lens fiber. One to 7 days after culture, the portion of LECs changed to spindle shape and the transdifferentiation resembled fibroblast. LM and EM observations indicated that changes of each LEC were lens fiber, and fibroblast. According to Western blot, the expression of alpha A-crystallin was increased by 10 days after culture. The alpha-smooth muscle actin showed an increased expression 10 to 30 days after culture. CONCLUSIONS: From the capsular bag model, we observed the resemblances of the differentiation and transdifferentiation of LECs with lens fiber and fibroblast.

Squamous Cell Carcinoma Involving Lacrimal Apparatus

Squamous cell carcinomas arising from the paranasal sinuses are often accompanied by eyeball pain, proptosis, decreased visual acuity and diplopia because of the proximity to the orbit. We report a case of squamous cell carcinoma of maxillary sinus mimicking chronic dacryocystitis and orbital cellulitis due to destruction of lacrimal apparatus.

Low tear production in patients with Diabetes Mellitus

To evaluate the realtionship of neural regulation of tear production and autonomic neuropathy, this study was assessed using Schirmer test, tear film break up time and diabetic autonomic neuropathy based on cardiovascular responses. 50 patients were recruited. The results were as follows. The more degree of autonomic neuropathy was present, the less tear production was found. There was a statistically significant difference between mean Schirmer test of normal group with autonomic neuropathy and mean Schirmer test of definitive group with autonomic neuropathy. The more degree of autonomic neuropathy was well correlated with the less tear film break up time. there was no statistically significant difference of mean tear film break up time among 3 groups with autonomic neuropathy. If the definitive group with autonomic neuropathy was screened by Schirmer test, the high sensitivity above 80% was achieved.

The Clinical Aspects of Blow-Out Fracture and Lyodura as an Orbital Floor Implants

From April 1989 to April 1993, 85 patients with orbital fractures were analysed. Among them, 10 patients were repaired surgically. Orbital fractures occured most frequently between the aga of 11 and 40 years. The main causes of injury were violence(41%), traffic accident (27%) and falldown injury (19%). Medial wall fractures were most common, followed by fractures of inferior wall, superior wall in order. In combined wall fracture, medial and inferior wall fracture was most frequent. The associated symptoms and signs of orbital fracture were lid laceration (32%), diplopia (29%). orbital edema(27%). traumatic iridocyclitis(22%). The subciliary approach was used for repair of the fracture. Early surgical intervention was done within 10 days in all cases. The insertion of Lyodura was performed in 9 patients. and calvarian bone graft was fashioned and placed over the defect in 1 patient. Insufficient correction of enophthalmos in 1 patient, lower eye lid retraction in 1 patient, residual diplopia in far upgaze in 2 patients were encountered as postoperative complications.