Free amino acid concentration in aqueous humour of patients with nuclear or cortical cataract
Since the free amino acids (a.a.) and derivated a.a. compounds in physiological fluids might reflect physiological or pathological conditions, some researchers have investigated the correlation of a.a. concentrations in physiological fluids with some clinical conditions, including ocular diseases. Here, we aimed to compare free and derivated a.a. in nuclear (generally a physiologic condition) and cortical (generally a pathologic condition) cataract. Materials and methods: Ten patients with nuclear and 10 with cortical cataract were included in this study. Aqueous humour a.a. and derivated a.a. compounds were determined by HPLC method (HP 1100) with Pickering post-column derivatization. Results: There was no significant difference between cortical and nuclear cataract groups in terms of aqueous humour total, glyco/ketogenic and standard a.a. contents, and nonessential (P < 0.01), glycogenic (P < 0.001) and ketogenic (P < 0.001) a.a. concentrations were found higher, and derivated (P < 0.001) a.a. concentrations were lower in the cortical cataract patients compared to the nuclear cataract patients. Conclusion: The present study suggests that there may be a difference between the nuclear and cortical cataract groups with respect to the contents of a.a. and derivated a.a. compounds in aqueous humour.
Free amino acid concentration in aqueous humour of patients with nuclear or cortical cataract
Since the free amino acids (a.a.) and derivated a.a. compounds in physiological fluids might reflect physiological or pathological conditions, some researchers have investigated the correlation of a.a. concentrations in physiological fluids with some clinical conditions, including ocular diseases. Here, we aimed to compare free and derivated a.a. in nuclear (generally a physiologic condition) and cortical (generally a pathologic condition) cataract. Materials and methods: Ten patients with nuclear and 10 with cortical cataract were included in this study. Aqueous humour a.a. and derivated a.a. compounds were determined by HPLC method (HP 1100) with Pickering post-column derivatization. Results: There was no significant difference between cortical and nuclear cataract groups in terms of aqueous humour total, glyco/ketogenic and standard a.a. contents, and nonessential (P < 0.01), glycogenic (P < 0.001) and ketogenic (P < 0.001) a.a. concentrations were found higher, and derivated (P < 0.001) a.a. concentrations were lower in the cortical cataract patients compared to the nuclear cataract patients. Conclusion: The present study suggests that there may be a difference between the nuclear and cortical cataract groups with respect to the contents of a.a. and derivated a.a. compounds in aqueous humour.
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