[Features of accumulation of chemical elements in the volume of the lens in senile cataract]. / Osobennosti nakopleniya khimicheskikh elementov v ob"eme khrustalika pri senil'noi katarakte.

PURPOSE: This study provides a detailed analysis of the bioinorganic chemical composition of lens substance in patients with senile cataract using classical and spatial statistics methods. MATERIAL AND METHODS: The study included 30 isolated human lenses. The light scattering ability (LSA) of the lens substance was evaluated using an original method. Additionally, distribution of chemical elements in the lens substance was analyzed using a scanning electron microscope with energy dispersive spectrometer (SEM/EDS). Measurements by all methods were carried out in a single coordinate space, which made it possible to compare the spatial correlation of different parameters. RESULTS: Small-angle light scattering of the lens substance has been quantitatively characterized for the first time. In contrast to the conventional norm, in senile cataract the accumulation fields of the majority of ion-forming elements (including Na, P, K, Cl) are distributed along the lines repeating the geometry of the lens capsule. At the same time, the light scattering ability of certain areas of the lens is significantly correlated with changes in the concentrations of Na, P, K, Ca in these areas. In particular, one ion-forming element can be distinguished - Na: spatial change of its concentration in senile cataract is strongly associated with a local change in LSA of the lens with opacities clustering of any degree. Thus, a change in the nature of the Na accumulation in the lens volume can be considered the main marker of senile cataract formation. CONCLUSION: The distribution pattern of ion-forming elements indicates that the loss of barrier properties in the capsule plays a significant role in the development of senile cataract.

[Accumulation of sulfur and phosphorus in the eye's drainage system in primary open-angle glaucoma]. / Nakoplenie sery i fosfora v drenazhnoi zone glaza pri pervichnoi otkrytougol'noi glaukome.

PURPOSE: To analyze the chemical composition of the sclera and trabecular meshwork in patients with primary open-angle glaucoma (POAG) and to assess the impact of corneal-compensated intraocular pressure (IOP) on the chemistry of the drainage area. MATERIAL AND METHODS: Biopsy specimens of the trabecular meshwork (89 specimens) and sclera (41 specimens) obtained from patients with POAG on maximal medical therapy were analyzed to determine the content of certain chemical elements - carbon (C), nitrogen (N), oxygen (O), aluminum (Al), calcium (Ca), chlorine (Cl), potassium (K), magnesium (Mg), sodium (Na), phosphorus (P), silicon (Si) and sulfur (S). The elements were selected based on chemical structure target tissue and sensitivity of the method used for analysis. Visualization was performed using the «EVO LS 10¼ (Zeiss, Germany) scanning electron microscope (SEM), and the chemical composition was studied with the «Oxford-X-MAX-50¼ (Oxford, UK) energy-dispersive spectrometer (EDS). Statistical analysis was performed using the Spearman correlation. RESULTS: The IOP of patients with POAG was found to have positive correlation with the total amount of S, P, and Ca in the trabecular meshwork. The accumulation of sulfur-containing compounds associated with pigment granules in trabecular meshwork's tissue was identified. A correlation was determined between the organic and inorganic (mineral) phosphorus content in the trabeculae, and the IOP values. The organic component of phosphorus was better represented than the mineral component in patients with increased IOP. CONCLUSION: In patients with POAG, an increase in the IOP level causes the amount of S associated with pigment granules and the proportion of organic P to increase in the trabecular meshwork, which should be taken into account in the further search for drug therapy that would potentially affect pathologically altered tissue.

Bioinorganic Markers of a Loss of the Crystalline Lens Capsule Barrier Properties and Consequent Age-Related Cataract Development.

The age-related cataract development consequent upon a loss of the lens capsule barrier properties proved to be associated with accumulation of sodium, calcium, phosphorus and potassium. For the first time the use of spatial cluster and correlation analyses showed that the physical light scattering in the crystalline lens volume depends on changes in the lens matter elemental composition. The fields of elevated concentrations of sodium, calcium, phosphorus, potassium and chlorine conformed to the lens capsule geometry and their clustering was similar to that of opacity fields in the lens body. The accumulation geometry of the elements in the lens body that are commonly seen in the aqueous humor of the anterior chamber, can be considered evidence for excessive transitioning of their compounds through the lens capsule shell, while its spatial connection with transparency changes-proof of participation in cataractogenesis.

[Nitrogen and oxygen levels in placenta - a predictor for retinopathy of prematurity]. / Uroven' azota i kisloroda v veshchestve platsenty - prediktor razvitiia retinopatii nedonoshennykh.

PURPOSE: To study the distribution of chemical elements in the placenta of pregnant women at 24-35 and 39-40 weeks of gestation, and to assess the possibility of using data on the levels of principle chemicals for predicting clinical manifestation of retinopathy of prematurity (ROP). MATERIAL AND METHODS: The study examined 375 placenta tissue fragments of pregnant women for levels of the following chemical elements: carbon (C), nitrogen (N), oxygen (O), calcium (Ca), chlorine (Cl), potassium (K), sodium (Na) and phosphorus (P). Subjects were divided into 3 groups: 1st group consisted of 41 pregnant females (205 fragments of placenta tissue) at weeks 24-35 of gestation, whose children would not develop ROP; 2nd group included 14 mothers (70 fragments of placenta tissue) at weeks 39-40 of gestation; 3rd group - 20 pregnant (100 fragments of placenta tissue) at weeks 24-35 of gestation, whose children would be diagnosed with ROP. Examination of the eye fundi of children from ROP risk group was done by digital retinoscopy and indirect binocular ophthalmoscopy. Chemical composition of placenta was studied using energy-dispersive x-ray microanalysis based on scanning electron microscopy. RESULTS: Descriptive statistical values of chemical elements were obtained for the three study groups. Statistically significant percentile differences were detected in the levels of C, N and O in the samples (p<2.2·10-16). Differences in the levels of N, O, K, and Na in the placenta of pregnant women of the three study groups were determined. CONCLUSION: Comparative chemical analysis of the placentas of pregnant women at different gestation periods showed higher levels of N, K, Na, and lower levels of O in the group of mothers whose children would be diagnosed with ROP. Normalized nitrogen content in the placenta of women whose children would develop ROP was 12.9%. Thus, nitrogen content may serve as a pre-clinical marker of retinopathy of prematurity.

[Bioinorganic chemical composition of the lens and methods of its investigation]. / Bioneorganicheskii khimicheskii sostav khrustalika i metody ego izucheniia.

Bioinorganic chemical composition of the lens of human and experimental animals (cows, dogs, rats, rabbits) have been analyzed in various studies. In most cases, the studies employed different methods to determine the gross (total) composition of chemical elements and their concentrations in the examined samples. Less frequently, they included an assessment of the distribution of chemical elements in the lens and correlation of their concentration with its morphological changes. Chemical elements from all groups (series) of the periodic classification system were discovered in the lens substance. Despite similar investigation methods, different authors obtained contradicting results on the chemical composition of the lens. This article presents data suggesting possible correlation between inorganic chemical elements in the lens substance with the development and formation of lenticular opacities. All currently employed methods are known to only analyze limited number of select chemical elements in the tissues and do not consider the whole range of elements that can be analyzed with existing technology; furthermore, the majority of studies are conducted on the animal model lens. Therefore, it is feasible to continue the development of the chemical microanalysis method by increasing the sensitivity of Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS) with the purpose of assessing the gross chemical composition and distribution of the elements in the lens substance, as well as revealing possible correlation between element concentration and morphological changes in the lens.