Introduction Good visual acuity was an ancient wish of mankind. In early ages good vision was a presumption of survival because hunting and fishing without it was impossible. Cataract was the main cause of blindness for thousands of years, and there
Authors:Kourosh Shahraki, Mohammad Naeim Amini Fard, Farkhondeh Shahri, Rama Pourmatin, Tafgeh Mohammadi, Paria Ghasemi Boroumand and Kianoush Shahraki
dehiscence, improper burial stitches, trapping the vitreous in the wound, the scleral tunnel, and unwanted conjunctival filtering bleb [ 1 ]. Wounds without sutures in cataract surgery can cause the organism gets into the eye after surgery. Since absolute
The knowledge of the role of trace elements is a necessary condition for the investigation of cataract etiopathogenesis. The deposition of trace elements in eye lens may be influenced by many vital factors and, therefore, the effect of sex, age and locality on the content of these elements was investigated. The determinations of elements were carried out by instrumental neutron activation analysis, and the results were evaluated with the aid of statistical tests. The effect of locality being taken as a set of local ecological factors has been proved as a dominant factor.
Authors:Hu Zhaohui, Zhang Jaiping, Lui Shirong, Zhong Min and Zhang Changjing
A cataract in the lenses of Wistar rats was induced by injecting Na2SeO3 into their bodies; they exhibited various kinds of cataract between 8 and 28 days. Samples were prepared using the method of low temperature ashing. The trace-element analyses of samples of different kinds of lenses were carried out by PIXE method. From the results obtained we have studied the ratio of their concentrations relative to the control values in relation to the formation time of cataract. It was found that the metabolites, of most trace-elements in the control lenses are stable, but in various kinds of cataractous lenses they display certain changes. Elements are clearly divided into two types. Elements of the first type are S, Cl, Ca, Fe and Zn. They appear to accumulate relative to the controls, while the second type, P, K and Rb, shows deficiency. The functions of trace-element metabolism during the formation of cataract are also discussed.
Authors:Zs. Biró, Vanda Nemes, G. Molnár, I. Wittmann, Andrea Ludány and D. Lőrinczy
of lens proteins play a crucial role in the formation of cataract, which is
among the leading causes of world blindness in the ageing population. Although
modern cataract surgery by phacoemulsification is a very successful and safe
procedure, the prevention of cataract formation would be a real breakthrough
in this field of ophthalmology.
The aim of our study was to analyse
the thermal denaturation of the cataractous lens proteins by the method of
differential scanning calorimetry (DSC), to understand cataract formation
and to work on its prevention possibilities. Samples were obtained from cataract
patients of different age, sex, patients with and without diabetes mellitus.
Samples were obtained from lenses of mature degree and progredient degree
of cataract as well.
Previous DSC examinations were performed
on manually extracted human cataractous lens materials, however to the best
of our knowledge, this is the first study, in which DSC examinations were
performed on lens materials obtained by the phacoemulsification technique,
which gained acceptance world-wide in the last decade.
Authors:Asaad A. Ghanem, Salah M. Mady, Lamiaa F. Arafa and Ahmed M. Elewa
To investigate the levels of 5-HT (serotonin, 5-hydroxytryptamine) and 5-HIAA (5-hydroxyindolacetic acid) in the aqueous humor and plasma of subjects with primary open-angle glaucoma (POAG) and to correlate their concentrations with the severity of glaucoma.
Thirty-five patients with POAG and 30 patients with senile cataract (control group) of matched age and gender were included in the study prospectively. Aqueous humor samples were obtained by paracentesis from glaucoma and cataract patients who were undergoing elective surgery. Aqueous humor and corresponding plasma samples were analyzed for 5-HT and 5-HIAA levels by high performance liquid chromatography with electrochemical detection.
5-HT and 5-HIAA levels were significantly higher in the aqueous humor of POAG patients than in that of the comparative group of cataract patients. There was no significant difference in the 5-HT and 5-HIAA levels in plasma of POAG and cataract patients. A positive correlation was found between 5-HT and 5-HIAA in the aqueous humor of POAG patients. The 5-HT turnover (5-HIAA/5-HT) was higher in POAG than in cataract patients, but the difference was not significant. No significant correlation was found between levels and severity of visual field loss.
Increased levels of 5-HT and 5-HIAA aqueous humor may be associated with POAG.