Identification of intraocular lens-adsorbed proteins in mammalian in vitro and in vivo systems.

OBJECTIVE: Mammalian in vitro and in vivo systems were used to study the protein-adsorbing potential of intraocular lenses (IOLs). METHODS: Intraocular lenses composed of polymethyl methacrylate optics with polypropylene haptics were incubated in rabbit plasma for 3 hours (in vitro grouping) or implanted in rabbit eyes for 48 hours (in vivo grouping). Lens-adsorbed proteins from both experimental groupings were eluted with sodium dodecyl sulfate and identified by Western Blot analyses. RESULTS: The adsorbed protein layer was composed of at least six different proteins: albumin, complement C3 fragments, IgG, fibrinogen/fibrin (as a fibrin clot in vivo), fibronectin, and transferrin. Of the identified components, albumin, IgG, fibronectin, and fibrinogen were the predominant protein species on the in vitro IOLs, while fibronectin and fibrin were on the in vivo IOLs. CONCLUSIONS: The composition of the protein layer has the potential to alter the biological property of IOLs.

Complement activation by surface modified poly(methyl methacrylate) intraocular lenses.

The complement activation potential of surface modified (passivated) poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) with polypropylene loops was compared to that of standard PMMA IOLs with polypropylene loops. Both lens types were incubated in human sera for six hours and then the C3a and C5a levels were measured by radioimmunoassay. Sera incubated with either IOL type generated significantly higher levels of C3a and C5a than control sera incubated without any IOL. The amount of C3a and C5a generated by the passivated PMMA IOLs was comparable to the levels generated by the standard PMMA IOLs. The results of this study show that surface passivated PMMA IOLs with polypropylene loops activated complement to the same level as standard PMMA IOLs with polypropylene loops.

Carcinoma of the rectum: a 10-year experience.

A consecutive series of 303 patients with carcinoma of the rectum and distal sigmoid colon treated by a single surgeon over a 10-year period are reported. Of these, 202 underwent an anterior resection, 85 an abdominoperineal excision of the rectum and 16 a coloanal anastomosis. Surgery was considered palliative in 52 patients undergoing anterior resection and 24 undergoing abdominoperineal resection. The 30-day hospital mortality rate was six patients (3 per cent) for anterior resection and two patients (2 per cent) for abdominoperineal resection. Peroperative anastomotic testing demonstrated leakage in five stapled anastomoses; these were rectified and no clinical sequelae occurred. Two patients (1 per cent) developed a clinical anastomotic leak, one of which proved fatal; in each case the intraoperative test was negative. The overall 5-year survival rate was 64 per cent after anterior resection and 52 per cent after abdominoperineal resection; the median follow-up was 64 months. The incidence of local pelvic recurrence was 6.4 per cent after anterior resection and 14 per cent after abdominoperineal (not significant). These results confirm the success of sphincter-saving anterior resection combined with total mesorectal excision, routine full mobilization of the splenic flexure and cancercidal lavage of the distal rectum in the treatment of low rectal carcinomas; morbidity, local recurrence and survival are not compromised.

Myopic keratomileusis: initial results and myopic keratomileusis combined with other procedures.

Myopic keratomileusis (MKM) was performed on 58 eyes to correct for moderate to severe myopia. This represents the first consecutive 58 cases I performed. Average follow-up was 11.6 months, with the shortest time being three months. Average preoperative myopia was -11.16 diopters (D) with a range of -5.50 D to -21.62 D. Average postoperative myopia was +0.38 D with a range of -7.75 D to +8.50 D. Selected patients (11) had secondary procedures such as homoplastic MKM, astigmatism procedures, or radial keratotomy. The average postoperative correction for all 58 cases was then +0.11 D with a range of -6.37 D to +4.00 D; 88.5% of patients achieved 20/50 or better uncorrected visual acuity. The procedures, postoperative course, and complications are discussed.

Trapezoidal relaxing incision for post keratoplasty astigmatism.

Eleven patients with high astigmatism after penetrating keratoplasty underwent a new form of relaxing keratotomy, the trapezoidal relaxing keratotomy, originally described by Ruiz. The average preoperative astigmatism was 7.89 diopters (range 4.25 to 12.50 diopters) with an average reduction in cylinder of 5.00 diopters (range 0-9.5 diopters). No complications were experienced.

Viral antigens in the immune ring of Herpes simplex stromal keratitis.

Corneal tissue obtained during superficial keratectomy from a patient with herpesvirus disciform keratitis was studied by immunoelectron microscopy. Clinically, this cornea had a dense central infiltrate with a circumferential opaque ring histologically resembling the immune ring described by Wessely. Histologically, along the line of altered keratocytes and ground substance, an infiltration of inflammatory cells was found. Herpesvirus particles were seen by electron microscopy in the corneal stroma, but these virus particles had abnormal, noninfective forms such as empty capsids and incomplete virions. By immunoelectron microscopy with a peroxidase-labeled antiherpesvirus antibody reagent, herpes-virus antigens were localized inthe corneal keratocytes and in the corneal stroma. The major localization of the virus antigens was in association with the herpes virions and surrounding vacuoles in the keratocyte nucleus and in the corneal stroma in the area of degenerating keratocytes. These findings support the view of a hypersensitivity mechanism in the pathogenesis of herpes simplex virus disciform keratitis.

HLA antigens in recurrent stromal herpes simplex virus keratitis.

HLA-A, HLA-B, and HLA-C antigens were typed on 48 patients with recurrent herpes stromal keratitis. The HLA-Aw30 antigen occurred three times more frequently in patients with herpes stromal keratitis than in those who lack the Aw30 antigen. When the data for the probability of the HLA-Aw30 were corrected for the number of variables studied, the corrected P value was not significant. A previous report of an increased frequency of HLA-B5 with recurrent herpes keratitis was not confirmed by our study. No significant associations with the HLA-C antigens were noted. HLA-DR antigen typing of 25 herpes stromal keratitis patients indicated that the HLA-DRw3 antigen appeared to have an increased frequency in herpes stromal keratitis. However, the small sample size studied precluded interpretation of the increased phenotypic frequency and the possible association of HLA-DRw3 and herpes stromal keratitis needs further study.

Elevated prostaglandin production in cultured cells from a patient with fibrodysplasia ossificans progressiva.

Prostaglandin E production was measured in cells cultured from both a fibromatoid lesion and a normal area of skin in a patient with fibrodysplasia ossificans progressiva. The synthesis of prostaglandin E-like material (iPGE) was ten- to twenty-fold greater in cells cultured from the patient's fibromatoid lesion than in fibroblasts obtained from her normal skin. Addition of indomethacin in vitro resulted in a greater than 95% reduction of iPGE production in both cell cultures. These observations appear to warrant further investigation in additional patients, with this disease.

Studies on alkaline phosphatase activity cultured cells from a patient with fibrodysplasia ossificans progressiva.

The cytoplasm of tumor cells from a subdermal nodule in a patient with fibrodysplasia ossificans progressiva (FOP) exhibited intense enzymatic activity in cryostat sections processed for demonstration of alkaline phosphatase. Nuclear heterochromatin and nucleoli, particularly in the area of the dense component, also showed strong reactivity. Finely minced blocks from the lesion of the patient with FOP revealed lighter reactivity which, in the tumor cells, avoided membrane limited spaces and appeared to be confined to hyaloplasm. Extracellular spaces disclosed very little or no reactivity and specimens from the patient's uninvolved skin lacked staining. The tumor cells from the subdermal nodule did not exhibit increased acid phosphatase activity. Cells (L-FOP) derived from a subdermal nodule and grown by tissue culture techniques also synthesized large amounts of prostaglandin E-like material and alkaline phosphatase. The amounts of prostaglandin E-like material synthesized by these L-FOP cells was reduced by more than 31 per cent by the antiinflammatory drugs indomethacin and sodium meclofenmate. Also, the production of alkaline phosphatase by these L-FOP cells was reduced by more than 40 per cent by ethane-1-hydroxyl-1,1-diphosphonate. Addition of prostaglandin E to nonlesion cells did not result in increased alkaline phosphatase activity.

Histochemical and ultrastructural studies in fibrodysplasia ossificans progressiva (myositis ossificans progressiva).

By light microscopy the subdermal nodule of a patient with fibrodysplasia ossificans progressiva (FOP) had a fibromatoid histologic appearance. The cytoplasm of the cells stained strongly for mannose-rich glycoprotein with the concanavalin A-horseradish peroxidase (con A-HRP) method. The tumors also exhibited abundant hyaluronidase-digestible mucopolysaccharide in the interstitium with various basic staining reagents. This material appeared to consist principally of hyaluronic acid or chondroitin sulfate with few or mainly masked sulfate esters. At the ultrastructural level, cells interpreted as the tumor cells in the subdermal nodule from the patient displayed extremely hyperplastic granular reticulum and well-developed Golgi elements and appeared very active in synthesis and secretion of protein. The material in the dilated cisternae of the granular reticulum stained for glycoprotein with the con-A-HRP method. Macrophages which comprised the other main cell type in the nodules commonly contacted the tumor cells and occasionally evidenced engulfment of these cells. The intercellular matrix of the nonossified subdermal nodule exhibited greatly increased mucosubstance and, by electron microscopy, showed an unusual network of dialyzed iron-reactive acid muco-substance in the interstitium.