Indocyanine green staining and removal of internal limiting membrane in macular hole surgery: histology and outcome

PURPOSE

To report the surgical technique, outcome, and histologic findings involving indocyanine green staining and removal of internal limiting membrane in primary macular hole surgery.

METHODS

Prospectively, consecutive patients with idiopathic macular hole or myopic macular hole with retinal detachment were recruited. After pars plana vitrectomy and epiretinal membrane removal, the internal limiting membrane was stained and removed. The specimens were stained using hematoxylin and eosin and periodic acid-Schiff. Immunohistochemical staining was also performed for glial fibrillary acidic protein, vimentin, type I and type IV collagen, and actin.

RESULTS

Among 10 patients (10 eyes) in the study, nine eyes had stage 3 or 4 macular hole. Four of them had chronic macular hole. The tenth patient had retinal detachment resulting from a myopic macular hole. Postoperatively, all cases had closure of macular hole without an elevated edge and the retina was attached. Seven patients had improvement of 2 or more Snellen lines, whereas visual acuity remained the same for the other three patients. In six eyes in which complete histologic examinations were feasible, internal limiting membrane was confirmed and two eyes also had a small amount of epiretinal membrane. Myofibrocytes in internal limiting membrane, either scattered or as a single layer, were found in three cases.

CONCLUSIONS

Removal of indocyanine green--stained internal limiting membrane around idiopathic macular hole or myopic macular hole with retinal detachment is confirmed with histology and may contribute to macular hole closure and retinal reattachment.

Association of EGFR gene fragments with nuclear matrices in glioblastoma cell lines

The association of epidermal growth factor receptor DNA fragments with nuclear matrix in glioblastoma cell lines was investigated. Two different DNA fragments (primer I-III, 940 bp and primer IV-V, 110 bp) were amplified in both genomic DNA and nuclear matrix-associated DNA. It was found that the 110 bp DNA fragment (primer IV-V) from a non-encoding region was more closely associated with the nuclear matrices of cell line U343, U373, A172, and T98 than with U87. The other DNA fragment (primer I-III) was found in both the genomic DNA and NM DNA from cell line of U343 and U87. Another long DNA fragment (primer I-II, 1015 bp) was not detected in the DNA of all cell lines. Our findings suggest that the attachment of the 110 bp DNA fragments to nuclear matrix may contribute to the growth and malignancy of glioblastoma.

A study on the relationship between antisense EGFR cDNA fragments and nuclear matrix proteins in glioblastoma cells

The association of antisense epidermal growth factor receptor (EGFR) cDNA fragments with nuclear matrix from EGFR-antisense transfected glioblastoma cell lines U343 and U87 was investigated. A 1015 bp DNA fragment (primer I-II) was amplified in both genomic DNA and nuclear matrix-associated DNA (NM DNA) from EGFR-antisense transfected glioblastoma cell lines U343E and U87E. Two different DNA fragments (940 bp and 110 bp) were amplified by primer I-III in both genomic DNA and NM DNA of U343E, while one 110 bp PCR product was shown with the same primer in both genomic DNA and NM DNA of U87E only. After EGFR-antisense transfection, the binding property of the 110 bp DNA fragment (primer IV-V) to nuclear matrix was not affected. Southwestern blotting demonstrated the presence of antisense EGFR cDNA binding nuclear matrix proteins. Our findings demonstrate that not only EGFR DNA is associated with nuclear matrix, but the transfected antisense EGFR cDNA also binds to nuclear matrix proteins. The nuclear matrix is most likely involved in the replication and transcription of antisense EGFR cDNA or hybridisation with sense mRNA in vitro.

Nuclear matrix of human ovarian cancer cells in vitro

The epithelial neoplasia constitute 60% of all primary tumors of the ovary and 90% of these are malignant. Nuclear matrix has been found to be involved in normal and abnormal nuclear activities. Previously, we have identified tumor-associated nuclear matrix proteins in cancers of human liver, nasopharynx and cervix. In this study, we compared nuclear matrices of immortalized ovarian and cancer cell lines by morphometric and 2-D gel electrophoresis analysis.