Sliding conjunctival flap for the treatment of primary pterygium.

BACKGROUND: The major problems after pterygium removal are recurrence and complications of the therapy. The authors investigated a simple surgical treatment without adjunctive therapy for primary pterygium. METHODS: Patients eligible to be included in the study were identified from a pterygium treatment log. They represent consecutive cases over a 6 1/2-year period, all of whom had been treated by one surgeon using a superior, sliding, conjunctival flap to cover the pterygium defect. An attempt was made to obtain follow-up of at least 1 year for each patient. RESULTS: Two hundred fifty-eight eyes in 236 patients were included in the study. Two hundred twenty-two eyes (86%) were able to be followed by either record review or re-examination. Seven pterygia (3.2%) recurred, all identified by record review, with no recurrences identified by re-examination. Recurrences were more likely after early postoperative flap retraction (5 of 7 recurrences) and recurrence occurred at a mean interval of 4.3 months (range, 1.5-11 months) after surgery. Symptomatically, the patients were comfortable, and the cosmetic result was good. CONCLUSION: This study indicates that this simple surgical procedure for the treatment of primary pterygium should be evaluated further by controlled clinical trials.

Calcium supplementation decreases rectal epithelial cell proliferation in subjects with sporadic adenoma.

The results of three small clinical trials examining the effect of calcium carbonate supplementation on the proliferation cytokinetics of the rectal epithelium in subjects with a current history of sporadic adenoma are reported. In six subjects, a daily administration of 1500 mg of calcium carbonate for 90 days failed to significantly suppress thymidine labeling in normal-appearing mucosa of the rectum. However, a daily dose of 2000 mg of calcium significantly (P = 0.008) altered mucosal proliferation in a second set of six subjects after a 30-day trial. Finally, a placebo-controlled trial of calcium (2000 mg) was conducted in which 20 subjects were randomized to groups receiving a 4-week intervention with calcium (or placebo), followed by the alternative treatment (placebo or calcium). The results of the study show a marked suppression of rectal proliferation during the calcium phase of the study but not during the placebo phase. This study adds to accumulating evidence showing that calcium supplementation regulates the proliferative behavior of colonic epithelium in the individual at high risk for colon cancer. Longer term trials of calcium supplementation will ascertain whether a continuing benefit from increasing dietary calcium translates into inhibition of adenoma recurrence.

Ulcerative colitis and colon cancer.

Chronic ulcerative colitis is an idiopathic inflammatory disease of the colon associated with an increased incidence of colorectal cancer. Colonoscopy with biopsy for mucosal dysplasia (precancer) can identify individuals with ulcerative colitis who are at increased risk for colorectal cancer. Identification of high-risk individuals can be used to guide clinical decisions regarding the timing and appropriateness of prophylactic colectomy.

Characterization of immunoglobulins from the brown bullhead (Ictalurus nebulosus) produced against a naturally occurring bacterial pathogen, Aeromonas hydrophila.

The primary immune response in the brown bullhead (Ictalurus nebulosus) to intramuscularly injected, chloroform-killed Aeromonas hydrophila reached an agglutination titer of 128 in 3 wk, and the response to the bacteria plus adjuvant reached a titer of 512 in 5 wk. Anti-Aeromonas hydrophila antibodies from brown bullheads were excluded from Sephadex G-200 and had an immunoelectrophoretic migration pattern toward the cathode. Cleavage of the macromolecule by 2-ME reduction and iodoacetamide alkylation yielded subunits that were resumptively heavy chains of about 50,500 daltons and light chains of about 22,500 daltons. Bullhead antibodies were assumed to be tetrameric in configuration and therefore to have an approximate molecular weight of 600,000 daltons assuming a J chain is present in both early (6 wk) and late (20 wk) immune sera. The agglutinating activity of the antibody was completely eliminated by exposure to 65 degrees C for 30 min. Immunoelectrophoresis showed a single antibody component that moved toward the cathode. The structure and molecular weight of bullhead antibodies appears similar to that observed in channel catfish and other closely related teleost fish.