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Purpose: Ultraviolet B (UVB) irradiation activates nuclear factor-kappa B (NF-κB) and inducible nitric oxide synthase (iNOS) in the cornea, resulting in inflammatory responses and malondialdehyde (MDA) accumulation. This study aims to determine the effect of zerumbone, a potent NF-κB inhibitor and inflammation modulators, on UVB-induced corneal damages in a mouse model., Methods: Fifty female imprinting control region (ICR) mice were randomly divided into five groups. The mice were anaesthetized with their ocular surfaces exposed to UVB light (0.72J/cm(2)/daily), followed by daily dietary zerumbone supplements at 0, 1, 10, and 100 mg/kg of bodyweight. Mice without zerumbone supplements were used as treatment controls and mice without UVB irradiation as blank controls. Corneal surface damages were graded according to smoothness, opacity, and the extent of lissamine green staining. Histopathological changes were also examined, along with the expression of NF-κB, iNOS, and tumor necrosis factor-α (TNF-α). MDA accumulation and the levels of two antioxidant enzymes, glutathione (GSH) and GSH reductase (GR) were also examined., Results: UVB irradiation caused significant damages to cornea, including sustained inflammation, apparent corneal ulcer, and severe epithelial exfoliation, leading to thinning of corneal epithelial layer, and infiltration of polymorphonuclear leukocytes. NF-κB expression was highly activated with nuclear translocation. The expression of iNOS and TNF-α were increased. MDA accumulation was also increased in both the corneal epithelial layer and the stroma. With dietary zerumbone, corneal damages were ameliorated in a dose-dependent manner. NF-κB activation and its nuclear translocation were blocked with decreased expression of iNOS and TNF-α. Infiltration of polymorphonuclear leukocytes was also blocked by dietary zerumbone. Besides, MDA accumulation was reduced with concomitant increase of GSH and GR levels., Conclusions: Dietary zerumbone prevents UVB-induced corneal damages by inhibition of NF-κB, iNOS, and TNF-α, with concomitant reduction of MDA accumulation and increase of GSH and GR levels in the mouse model. Results of this study suggest that dietary zerumbone may be used as a prophylactic agent against UVB-induced photokeratitis.

Purpose: To report nine cases of tyrosinemia type II, with ocular signs and symptoms., Methods: Participants included nine patients (18 eyes) who were followed for a mean follow-up period of 6.5 years (range, 2 to 8 years). Intervention included dietary restriction of tyrosine and phenylalanine, which led to resolution of ocular and cutaneous lesions, improved behavior in one patient, and may have prevented developmental delay in others. The main outcome measures were visual acuity and serum tyrosine levels to determine the response to dietary therapy. Intelligence testing and developmental screening were performed when appropriate., Results: All patients presented with ocular signs and symptoms as the primary manifestation of disease and serve to illustrate the typical ocular findings of this syndrome. Three patients presented with cutaneous manifestations, and one patient had mild mental impairment at the time of diagnosis., Conclusions: Recalcitrant pseudodendritic keratitis may be the presenting sign in tyrosinemia type II. Awareness of the presenting signs and symptoms may accelerate the diagnosis and dietary intervention. Initiation of a tyrosine-restricted and phenylalanine-restricted diet in infancy is most effective in preventing cognitive impairment.

A boy of 3 2/12 years of age with Richner-Hanhart syndrome (plantar and palmar keratosis and chronic keratitis) was found to have hypertyrosinemia and to excrete the hydroxyacids derived from tyrosine. A diet poor in phenylalanine and tyrosine cured the skin and corneal lesions. Clinical and biochemical observations are reported.

One should henceforth systematically search for hypertyrosinemia which, too often, goes unrecognized for years, in patients presenting chronic keratitis associated with palmar and plantar hyperkeratosis. As a matter of fact, this highly crippling disease may be cured with an appropriate diet and the diagnosis, once suspected, is easily confirmed by simple investigations.

An 11-year-old girl with keratitis and plantar keratosis had tyrosinemia. The concentration of tyrosine in the plasma was 16.5 mg/dL. Dietary intake of phenylalanine and tyrosine was systematically varied, and the plasma concentrations of tyrosine and nitrogen balance were studied. It was necessary to achieve a total intake of phenylalanine and tyrosine less than 100 mg/kg/day to obtain plasma concentrations of tyrosine of less than 10 mg/dL. After dietary therapy was started, the keratitis resolved promptly, and the patient remained asymptomatic during a period of 16 months in which the mean plasma concentration of tyrosine was 11.1 mg/dL. The dietary management of a child at this age presents a different problem from that of a young infant. It can be successfully pursued at home, as well as in the carefully regulated environment of a clinical research center.