Tomasz Kryczka

Influence of donor age, post-mortem time and cold storage on metabolic profile of human cornea.

Purpose:  Limited knowledge exists about the influence of donor age and death‐to‐preservation interval (DPI) on the metabolic properties of the cornea. The aim of this study is to investigate the relationship between both factors and metabolite content of the cornea.

Impact of organ culturing on metabolic profile of human corneas: preliminary results.

Purpose:  It is suggested that the quality of corneal graft may depend on modifications that appear in the tissue during culturing. The aim of this study was to investigate the differences in the metabolic profile between cultured and noncultured human corneas.

Metabolic Profile of Keratoconic Cornea

Abstract Purpose: To investigate the difference in metabolic profile of keratoconic and normal corneas using two different analysis methods. Methods: Keratoconic corneas were obtained from patients (aged 19–27) during transplantation surgery. Control samples were obtained from human donors (aged 61–75) 1–8 h post-mortem. The metabolic profile of tissues was investigated with high-resolution magic angle spinning 1H nuclear magnetic resonance (NMR) spectroscopy and high performance liquid chromatography (HPLC). Results: Nine amino acids and 20 metabolites were assigned with HPLC and NMR spectroscopy, respectively. No significant biochemical difference was revealed between keratoconic and control samples, which represent distant age groups. Conclusions: It suggests that development of keratoconus might be related to the accelerated ageing of the cornea. This issue warrants further studies.

NMR Spectroscopy of Human Eye Tissues: A New Insight into Ocular Biochemistry

Background. The human eye is a complex organ whose anatomy and functions has been described very well to date. Unfortunately, the knowledge of the biochemistry and metabolic properties of eye tissues varies. Our objective was to reveal the biochemical differences between main tissue components of human eyes. Methods. Corneas, irises, ciliary bodies, lenses, and retinas were obtained from cadaver globes 0-1/2 hours postmortem of 6 male donors (age: 44–61 years). The metabolic profile of tissues was investigated with HR MAS 1H NMR spectroscopy. Results. A total of 29 metabolites were assigned in the NMR spectra of the eye tissues. Significant differences between tissues were revealed in contents of the most distant eye-tissues, while irises and ciliary bodies showed minimal biochemical differences. ATP, acetate, choline, glutamate, lactate, myoinositol, and taurine were identified as the primary biochemical compounds responsible for differentiation of the eye tissues. Conclusions. In this study we showed for the first time the results of the analysis of the main human eye tissues with NMR spectroscopy. The biochemical contents of the selected tissues seemed to correspond to their primary anatomical and functional attributes, the way of the delivery of the nutrients, and the location of the tissues in the eye.

Metabolic profile of porcine corneas after photodynamic cross-linking treatment.

als suffering from epiphora are likely to be over-represented. In conclusion, this is the first study to investigate the relationship between CNLDO and epiphora in early adulthood. Our findings would suggest that CNLDO in infancy, which is not probed prior to 12 months of age, is not related to epiphora in adult life and that blepharitis ⁄ allergic conjunctivitis are more important causes of tearing. However, further studies are needed to address the question of whether CNLDO predisposes to symptomatic outflow obstruction in later adult life.

Monitoring of in vitro dynamics of Acanthamoeba strains isolated from infected eyes as a useful tool in keratitis management

Free-living amoebae of Acanthamoeba genus are ubiquitous in various parts of the world. Some species of these amoebozoans present a serious risk to human health as the causative agents of vision-threatening diseases, Acanthamoeba keratitis. Correct diagnosis requires both a clinical examination of the cornea and amoebic form identification in affected eyes. Despite advances in pharmacotherapy, the infection is difficult to diagnose and to threat. Population dynamics of five different Acanthamoeba strains cultured in vitro under bacteria-free condition in BSC medium, was monitored in terms of diagnostic and therapeutic management. The range of protozoan number in the exponential growth phase, the morpho-physiological status of amoeba forms and their ability to multiply were evaluated. Results of the studies revealed that early and continued monitoring of the strains maintained in an axenic culture showed correlation between the dynamics of cultivated amoebae and the course of the disease, differences in response to pharmacotherapy and the surgical management efficacy. Concluding, the in vitro monitoring of dynamics of Acanthamoeba strains isolated from infected corneas may be important not only for proper diagnosis but also as a useful tool in keratitis management and therapeutic prognosis.

Impact of donor health on corneal biochemistry – an unexpected caveat from a pilot study

BACKGROUND To test the possibility that some chronic systemic maladies not directly related to the function of the eye may significantly and permanently disturb corneal metabolism. MATERIAL/METHODS Contents of selected low molecular weight metabolites were compared among corneas collected from donors who died suddenly of an accident or non-poisoning suicide, or met a sudden non-accidental death from unidentified causes, or died of a chronic cardiovascular disease or of idiopathic liver cirrhosis (N=4 for each group). Corneal buttons were halved; one half was snap-frozen and stored at -80°C, and the other half was stored at +4°C in Eusol-C for 8 days and then was snap-frozen and stored at -80°C until analyzed. Metabolite contents were assessed using high-resolution magic angle spinning proton NMR spectroscopy. RESULTS Significant between-group differences in corneal biochemical profiles were identified. Most of them were reduced or nullified by the Eusol-C storage, suggesting their link to differences in in vivo corneal environment. The corneas from donors with liver cirrhosis or cardiovascular diseases differed considerably from the remaining ones, both before and after the Eusol-C storage. CONCLUSIONS Various chronic systemic diseases that are not directly related to the function of the eye markedly affect corneal biochemistry. Some of the alterations are likely related to a permanent aberration in corneal metabolism. A study is warranted in larger donor groups on the effect of idiopathic liver cirrhosis and cardiovascular diseases on corneal metabolism and/or a retrospective analysis of the long-term outcome of keratoplasty and other grafting procedures employing materials from these donor groups.