The Effectiveness of Laser Peripheral Iridotomy in Adolescent Eyes with Ocular Hypertension and Concave Configuration of the Peripheral Iris.

Purpose: To evaluate the efficacy of laser peripheral iridotomy (LPI) in preventing deterioration in eyes with ocular hypertension (OHT) and concave configuration of the iris. Materials and Methods: This was a retrospective study, which was carried out within a period of 3-5 years. Twenty-four patients with OHT and concave irises were treated with LPI and followed up periodically. IOP, central corneal thickness (CCT), anterior chamber depth (ACD), scleral spur angle (SSA), global neuroretinal rim (NRR) thickness, and global retinal nerve fiber layer (RNFL) were examined before and after LPI. Results: The average age of the 24 patients was 14.21 ± 1.41 (13-17.5) years on admission. The initial IOP of the 48 eyes was 23.21 ± 1.56 mmHg in RE and 22.96 ± 2.1 mmHg in LE before LPI. All 48 eyes had concave irises in both eyes. All eyes treated with LPI have shown iris flattening, which has persisted during follow-up (mean 1.54 ± 0.9 years). At the last follow-up visit, the average IOP was 17.58 ± 2.63 (14-21) mmHg in RE and 17.58 ± 2.86 (14-21) mmHg in LE, which was statistically lower than that of the baseline (p < 0.001). There were significant changes in SSA in both eyes and global RNFL in RE after LPI. Conclusions: In the current study, LPI resulted in an IOP-lowering effect and iris flattening in adolescent eyes with a concave configuration of the peripheral iris.

Oblique Survival Trees in Discrete Event Time Analysis.

One of the main objectives of survival analysis is to predict the failure time that is usually considered as a continuous variable. In longitudinal studies, the data are often collected at every certain period of time, for example, monthly, quarterly, or yearly. Such data require appropriate techniques to handle the discrete time values that often have incomplete information about the failure occurrence-so-called "censored cases." Tree-based models are common, assumption-free methods of survival prediction. In this paper, the author proposes three recursive partitioning techniques able to cope with discrete-time censored survival data, which, in contrast to already-existing models limited to univariate trees, allow splits to have a form of any hyperplane. The performance of proposed methods, expressed as a mean absolute error, was examined on the basis of both synthetic and real data sets available in the literature and compared with existing tree-based models. To demonstrate the applicability of the methods in identifying subgroups of patients with a similar survival experience and to assess the influence of covariates on the risk of failure, a Veteran's Administration lung cancer data set was used. The results confirm proposed models to be good prediction tools for discrete-time survival data.

Concentration of Zinc, Copper, Selenium, Manganese, and Cu/Zn Ratio in Hair of Children and Adolescents with Myopia.

The aim of this work was to determine the concentration of trace elements, zinc, copper, selenium, manganese, and Cu/Zn ratio, in scalp hair samples of children and adolescents with myopia. The study included 92 children (mean age 14.5 ± 2.5 years) with myopia and 43 healthy persons (mean age 11.8 ± 4.7 years). Each patient had a complete eye examination. Trace element concentrations in hair were determined by atomic absorption spectrometry. Cu/Zn ratio was also calculated. The zinc level in the hair of myopic patients was significantly higher (260 µg/g) in comparison to the control group (130 µg/g). There was a significantly lower Cu/Zn ratio in myopic patients (0.045) compared with controls (0.07). An insignificant difference was observed in the hair level of copper, selenium, and manganese between patients and controls. The results show that trace elements may play a significant role in the pathogenesis of myopia. Further studies should pay more attention to determine the effect of trace element on children myopia.

Tree-based models for survival data with competing risks.

OBJECTIVE: Tree-based models belong to common, assumption-free methods of data analysis. Their application in survival data is narrowed to univariate models, which partition the feature space with axis-parallel hyperplanes, meaning that each internal node involves a single feature. In this paper, I extend the idea of oblique survival tree induction for competing risks by modifying a piecewise-linear criterion function. Additionally, the use of tree-based ensembles to analyze the competing events is proposed. METHOD AND MATERIALS: Two types of competing risks trees are proposed: a single event tree designed for analysis of the event of interest and a composite event tree, in which all the competing events are taken into account. The induction process is similar, except that the calculation of the criterion function is minimized for the individual tree nodes generation. These two tree types were also used for building the ensembles with aggregated cumulative incidence functions as an outcome. Nine real data sets, as well as a simulated data set, were taken to assess performance of the models, while detailed analysis was conducted on the basis of follicular cell lymphoma data. RESULTS: The evaluation was focused on two measures: the prediction error expressed by an integrated Brier score (IBS), and the ranked measure of predictive ability calculated as a time-truncated concordance index (C-index). The proposed techniques were compared with the existing approaches of the Fine-Gray subdistribution hazard model, Fine-Gray regression model with backward elimination, and random survival forest for competing risks. The results for both the IBS and the C-index indicated statistically significant differences between these methods (p < .0001). CONCLUSIONS: The prediction error of the individual trees was similar to the other methods, but the results of the C-index differ in comparison to the Fine-Gray subdistribution hazard model and the Fine-Gray regression with backward elimination. The ensembles prediction ability was comparable to existing algorithms, but their IBS values were better than either random survival forest or Fine-Gray regression with backward elimination.

Piecewise-linear criterion functions in oblique survival tree induction.

OBJECTIVE: Recursive partitioning is a common, assumption-free method of survival data analysis. It focuses mainly on univariate trees, which use splits based on a single variable in each internal node. In this paper, I provide an extension of an oblique survival tree induction technique, in which axis-parallel splits are replaced by hyperplanes, dividing the feature space into areas with a homogeneous survival experience. METHOD AND MATERIALS: The proposed tree induction algorithm consists of two steps. The first covers the induction of a large tree with internal nodes represented by hyperplanes, whose positions are calculated by the minimization of a piecewise-linear criterion function, the dipolar criterion. The other phase uses a split-complexity algorithm to prune unnecessary tree branches and a 10-fold cross-validation technique to choose the best tree. The terminal nodes of the final tree are characterised by Kaplan-Meier survival functions. A synthetic data set was used to test the performance, while seven real data sets were exploited to validate the proposed method. RESULTS: The evaluation of the method was focused on two features: predictive ability and tree size. These were compared with two univariate tree models: the conditional inference tree and recursive partitioning for survival trees, respectively. The comparison of the predictive ability, expressed as an integrated Brier score, showed no statistically significant differences (p=0.486) among the three methods. Similar results were obtained for the tree size (p=0.11), which was calculated as a median value over 20 runs of a 10-fold cross-validation. CONCLUSIONS: The predictive ability of trees generated using piecewise-linear criterion functions is comparable to that of univariate tree-based models. Although a similar conclusion may be drawn from the analysis of the tree size, in the majority of the studied cases, the number of nodes of the dipolar tree is one of the smallest among all the methods.

The assessment of multifocal ERG responses in school-age children with history of prematurity.

PURPOSE: The authors examined macular function in preterm-born children, using multifocal ERG (mfERG). Possible alterations in P1 amplitudes, P1 amplitudes density and P1 implicit time between school-age children with history of prematurity and their peers were researched. The correlations between parameters of mfERG responses and birth weight, gestational age, macular volume and central macular thickness were verified. METHODS: A group of 18 preterm-born school-age children were analyzed (mean age 10.18 ± 1.21 years). The study group was compared to the group of 15 peers born appropriate for gestational age (mean age 10.8 ± 1.52 years). The mfERG was evaluated in all children. RESULTS: There were statistically significant differences for P1 amplitudes from ring 1 (p = 0.0001) and P1 amplitudes density from ring 1 (p = 0.0001). Calculating the correlation coefficients, we receive significant results for P1 amplitudes from ring 1 versus gestational age (r = 0.54; p = 0.026), birth weight (r = 0.54; p = 0.026) and central macular thickness (r = -0.62; p = 0.008), and for P1 amplitudes density from ring 1 versus central macular thickness (r = -0.51; p = 0.034). CONCLUSIONS: The study suggests that P1 amplitudes and P1 amplitudes density vary in preterm-born children in comparison with their peers born appropriate for gestational age, which might suggest discreet macular dysfunction. The correlation between low birth weight, early gestational age, central macular thickness and mFERG components from ring 1 might evidence that decreased bipolar cells density caused by premature birth is the result of altered development of central retina reflecting in structural anomalies of the fovea.

Evaluation of corneal endothelium in adolescents with juvenile glaucoma.

Purpose. To evaluate the endothelial cell density (ECD) and central corneal thickness (CCT) in adolescents with juvenile open-angle glaucoma (JOAG) and ocular hypertension (OH) and to investigate the influence of topical antiglaucoma medications on ECD and CCT in adolescents with JOAG. Methods. ECD and CCT were investigated in 66 eyes of 33 adolescents with JOAG. Depending on the topical treatment the eyes were classified into 4 groups: (1) topical carbonic anhydrase inhibitor, (2) prostaglandin analogs, (3) beta-blocker, and (4) CAI-beta-blocker combination. ECD and CCT were also checked in 24 adolescents with OH and in control group (33 persons). Results. ECD was significantly lower in eyes with JOAG (2639.5 cells/mm(2)) compared with ECD in eyes with OH (2924.5 cells/mm(2)) and in control group (2955.5 cells/mm(2)). CCT was 0.554 mm in eyes with JOAG, 0.55 mm in eyes with OH, and 0.544 mm in control group. ECD in patients with JOAG was 2730 cells/mm(2) (1 group), 2773.5 cells/mm(2) (2 group), 2539.5 cells/mm(2) (3 group), and 2551 cells/mm(2) (4 group). CCT was 0.556 mm in 1 group, 0.558 mm in 2 group, 0.532 mm in 3 group, and 0.544 mm in 4 group. Conclusions. Our findings indicate that JOAG and OH did not affect CCT, but JOAG has influence on ECD in adolescents. There were no significant differences between ECD and CCT of eyes treated with different kinds of antiglaucoma medications.

Chemokines profiling of patients with preterm birth.

INTRODUCTION: Nowadays it is thought that the main cause of premature birth is subclinical infection. However, none of the currently used methods provide effective prevention to preterm labor. The aim of the study was to determine the concentration of selected chemokines in sera of patients with premature birth without clinical signs of infection (n = 62), threatened preterm labor (n = 47), and term births (n = 28). METHOD: To assess the concentration of chemokines in the blood serum, we used a multiplex method, which allows the simultaneous determination of 40 chemokines per sample. The sets consist of the following chemokines: 6Ckine/CCL21, Axl, BTC, CCL28, CTACK/CCL27, CXCL16, ENA-78/CXCL5, Eotaxin-3/CCL26, GCP-2/CXC, GRO (GRO α /CXCL1, GRO ß /CXCL2 and GRO γ /CXCL3), HCC-1/CCL14, HCC-4/CCL16, IL-9, IL-17F, IL18-BPa, IL-28A, IL-29, IL-31, IP-10/CXCL10, I-TAC/CXCL11, LIF, LIGHT/TNFSF14, Lymphotactin/XCL1, MCP-2/CCL8, MCP-3/CCL7, MCP-4/CCL13, MDC/CCL22, MIF, MIP-3 α /CCL20, MIP-3- ß /CCL19, MPIF-1/CCL23, NAP-2/CXCL7, MSP α , OPN, PARC/CCL18, PF4, SDF-1/CXCL12, TARC/CCL17, TECK/CCL25, and TSLP. RESULTS: We showed possible implication of 4 chemokines, that is, HCC-4, I-TAC, MIP-3 α , and TARC in women with symptoms of preterm delivery. CONCLUSION: On the basis of our findings, it seems that the chemokines may play role in the pathogenesis of preterm labor. Defining their potential as biochemical markers of preterm birth requires further investigation on larger group of patients.

Evaluation of corneal endothelium in children and adolescents with type 1 diabetes mellitus.

PURPOSE: To evaluate the systemic and local factors that contribute to the damage of endothelial cells in diabetic patients and to compare the endothelial structure of the cornea in diabetic and nondiabetic patients. MATERIALS AND METHODS: The endothelial cell density (ECD) and central corneal thickness (CCT) were investigated in 123 eyes of type 1 diabetic patients and in 124 eyes of nondiabetic patients. The mean diabetic patients age was 15.34 ± 3.06 years versus 14.58 ± 2.01 years in the control group. The mean duration of diabetes was 8.02 ± 3.9 years. The corneal endothelium was imaged by the Topcon SP-2000P. RESULTS: The mean ECD in diabetic eyes was 2435.55 ± 443.43 cells/mm(2) and was significantly lower than in control group (2970.75 ± 270.1 cells/mm(2)). The mean CCT was 0.55 ± 0.03 mm in diabetic group versus 0.53 ± 0.033 mm in control group. ECD and CCT significantly correlated only with duration of diabetes. There was no correlation between ECD and CCT and patient age, sex, HbA1C level, and plasma creatinine level. CONCLUSIONS: ECD is decreased and CCT is increased in children and adolescents with diabetes mellitus. Duration of diabetes is the factor that affects ECD and CCT.

[Evaluation of anterior chamber depth measurements in emmetropic, hypermetropic and myopic eyes in children and adolescents using OCT Visante]. / Ocena przedniego odcinka oczu normowzrocznych, nadwzrocznych i krótkowzrocznych u dzieci i mlodziezy za pomoca optycznej koherentnej tomografii OCT Visante.

PURPOSE: To evaluate the anterior chamber depth (ACD) measurements in emmetropic, hypermetropic and myopic eyes in children and adolescents using optical coherence tomography (OCT). MATERIAL AND METHODS: 86 patients at the age from 4 to 17 years were examined. 27 patients with mean age 14.0 +/- 2.94 years had myopia with spherical equivalent refraction (RE) from -0.50 to - 19.50 D (mean RE = -8.63 +/- 3.89 D). 29 patients with mean age 8.7 +/- 1.95 years had hypermetropia with RE from +0.50 to +9.00 D (mean RE = +4.49 +/- 2.11 D). 30 patients control group) with mean age 9.8 +/- 1.03 years had emmetropia. The anterior chamber depth was measured by OCT Visante. In myopic eyes measurements of axial length were obtained using ultrasound A scan. RESULTS: 172 eyes (86 subjects) were evaluated. The mean ACD measurement was 3.18 +/- 0.31 mm in myopic eyes, 2.73 +/- 0.2 mm in hypermetropic eyes, and 2.92 +/- 0.11 mm in emmetropic eyes. There were significant differences in ACD between these three groups of eyes (p<0.01). ACD was correlated with spherical equivalent refraction (Spearman correlation, r = -0.688, p<0.001), and axial length (r = 0.388, p = 0.003) in myopic eyes. There were no statistically significant differences in ACD between 30 eyes of 15 patients with anisometropia >3.00 D. CONCLUSIONS: There were significant differences in ACD between emmetropic, hypermetropic and myopic eyes in children and adolescents. ACD was associated with refractive error and axial length in the eyes with myopia. Further observations are necessary on larger number of patients.

Total matrix metalloproteinase-8 serum levels in patients labouring preterm and patients with threatened preterm delivery.

Preterm labour and prematurity are still a main cause of perinatal morbidity nowadays. The aim of our study was to assess the role of MMP-8 as a predictive marker of preterm delivery. Four groups of patients were involved to the study: I - pregnant women at 24-34 weeks of gestation with any symptoms of threatened preterm labour; II - threatened preterm labour patients between 24-34 weeks of gestation; III - preterm vaginal delivery patients; IV - healthy term vaginal delivery patients. Serum concentration of total MMP-8 was measured using two enzyme-linked immunosorbent assays. There were no significant differences in the median concentrations of total MMP-8 between physiological pregnancy and threatened preterm labour patients with existing uterine contractility. No significant differences of total MMP-8 were either found between healthy term and preterm labouring patients. The studies on a larger population are needed to reject the hypothesis that preterm labour is connected with increased MMP-8 plasma concentrations of women in preterm labour and threatened preterm delivery.

[Evaluation of central corneal thickness in children and adolescents with type I diabetes mellitus]. / Analiza centralnej grubosci rogówki u dzieci mlodziezy z cukrzyca insulinozalezna.

PURPOSE: To evaluate corneal thickness in diabetic and nondiabetic patients. MATERIALS AND METHODS: The central corneal thickness (CCT) was investigated in 100 eyes of 100 patients with diabetes type I and in 99 nondiabetic patients (99 eyes). The mean diabetic patients age was 15.31 +/- 3.18 years. The mean age in control group was 14.3 +/- 2.2 years. Corneal thickness was measured by non-contact microscope Topcon SP-2000P Statistical analysis was performed to assess systemic factors (patient age, sex, duration of diabetes mellitus, hemoglobin A1c value, diabetes control) related to CCT. SAS STAT (Release 8.2) program, the independent t-test, Kolmogorow-Smirnow test and Bartlett test were used to compare differences between the diabetic and control group. RESULTS: In our study the mean CCT in diabetic eyes was 0.54 +/- 0.03 mm and was significantly increased, compared to control group (0.525 +/- 0.037 mm). None of systemic factors was correlated with CCT. CONCLUSIONS: Our findings indicate that diabetes mellitus affects thickness of cornea in adolescents. Evaluation of endothelium in specular microscope should be performed in the diabetic patients.

[Evaluation of corneal endothelium after pediatric cataract surgery in children and adolescents]. / Ocena sródblonka rogówki po operacjach usunigcia zacmy u dzieci i mlodziezy.

PURPOSE: to evaluate the effects of cataract extraction and lens implantation on corneal endothelium morphology. MATERIAL AND METHODS: In 21 eyes of 14 children with congenital or developmental cataract, corneal endothelium was studied. Patient age was 9 to 19 years (mean 12.9 years). In all eyes extracapsular cataract extraction (ECCE) with PMMA intraocular lens implantation was performed, without primary posterior capsulotomy or anterior vitrectomy. Lens wearers, patients with traumatic cataract or external eye diseases and ocular surgery in history were excluded. The endothelium was imaged by non-contact microscope Topcon SP-2000P. This examination was done preoperatively and 1 month, 6 months and 1 year postoperatively. Corneal thickness (T), corneal endothelial density (ECD) and mean cell area (AVG) of endothelial cells were examined. RESULTS: Mean corneal thickness was 0.55 mm after 1 month, 0.54 mm after 6 months and 0.54 mm after 12 months. The mean preoperative endothelial cell density was 3231.1 cells/mm2. ECD after 1.6 and 12 months was 2874.3; 2639.2 and 2479.9 cells/mm2 respectively. Mean endothelial cell loss was 10.94% after 1 month, 17.85% after 6 months and 22.68% after 12 months. AVG before operation was 315.8 mm2, after 1 month 355.8 mm2, after 6 months 382.4 mm2 and 399.5 mm2 after 12 months. CONCLUSIONS: Changes in corneal endothelium morphology had no effect on transparency of the cornea.

Antenatal corticosteroid therapy: a comparative study of dexamethasone and betamethasone effects on fetal Doppler flow velocity waveforms.

OBJECTIVE: To compare the effects of antenatal administration of dexamethasone and betamethasone, used in two different regimens, on fetal Doppler flow velocities. STUDY DESIGN: Sixty-seven women at risk for preterm delivery received course of corticosteroids by means of a computer-generated randomization table. The Doppler examination of the pulsatility index (PI) of the umbilical artery (UA), the middle cerebral artery (MCA) and the middle cerebral artery/umbilical artery PI ratio (MCA PI/UA PI) were performed before treatment, 24 and 72 h after the first dose of corticosteroids. The SAS system was used to perform statistical analysis. RESULTS: No significant change was observed in UA PI through dexamethasone therapy. In MCA there was a significant decrease in PI at 72 h (2+/-0.43 before and 1.68+/-0.31 after, p=0.0001). Similarly a significant decrease in MCA PI/UA PI ratio was noted (2.09+/-0.51 before and 1.83+/-0.4 after, p=0.0137). No significant changes were observed in UA PI, MCA PI and MCA PI/UA PI ratio during betamethasone treatment. CONCLUSIONS: Our results indicate significant decrease in fetal middle cerebral artery impedance at 72 h after maternal administration of the first dose of dexamethasone. Effects of dexamethasone on fetal brain warrants further research.

[Effect of pentoxifylline on Doppler blood flow parameters in the central retinal artery and the short posterior ciliary arteries in adolescents with progressive myopia]. / Wplyw pentoksyfiliny na dopplerowskie parametry przeplywu krwi w tetnicy srodkowej siatkówki i w tetnicach rzeskowych tylnych krótkich u mlodziezy z krótkowzrocznoscia postepujaca.

PURPOSE: To evaluate the effect of pentoxifylline on blood flow in the central retinal artery and the short posterior ciliary arteries in patients with progressive myopia. MATERIAL AND METHODS: 48 eyes of 24 healthy patients aged between 12 and 18 years (mean 15.1 years) with myopia from -5.0 to -12.75 Dsph (mean -7.56 Dsph), were examined using color Doppler ultrasonography. The examination was performed before and after 10 days of intravenous administration of 200 mg of pentoxifylline. The peak-systolic, end-diastolic flow velocities, pulsatility, resistance and systolic/diastolic ratios were measured. RESULTS: The use of pentoxifylline significantly increased PSV and EDV in the central retinal artery and in the short posterior ciliary arteries (p=0.0001) in patients with progressive myopia and in the same time decreased PI, RI and S/D (p=0.0001). There was no correlation between Doppler blood flow parameters and dioptres or axial length. CONCLUSIONS: pentoxifylline increases retinal and choroidal blood flow in young patients with progressive myopia.

[Evaluation of serum sICAM-1 and sVCAM-1 concentration in patient at risk of preterm delivery]. / Ocena stezen czastek adhezyjnych sICAM-1 i sVCAM-1 w surowicy krwi pacjentek z zagrazajacym porodem przedwczesnym.

Aim of the study was to assess the serum adhesion molecules concentration in patients at risk of preterm labour. Sixty-three patients were divided into two groups basing on cervical evaluation (Bishop's score > or = 6 and < 6). The assessment of sICAM-1 and sVCAM-1 levels in serum were carried out by immunoenzymatic ELISA test utilizing monoclonal antibodies (moAb) against human sICAM-1 and sVCAM-1 (ELISA system, R&Q, USA). Among the patients at risk of preterm labour and Bishop's score > or = 6 statistically higher serum levels of sICAM-1 were found. There were no statistically significant differences in sVCAM-1 levels between examined groups. We conclude that serum sICAM-1 determination might improve the prediction of preterm birth.

Intercellular adhesion molecule 1 gene polymorphisms in Graves' disease.

It was recently suggested that genetic factors could play a major role in the development of Graves' disease (GD). The aim of the present study was to evaluate the frequency of the c.721G-->A polymorphism and the c.1405A-->G polymorphism of the intercellular adhesion molecule 1 (ICAM-1) gene in subjects with GD compared with that in healthy controls, because ICAM-1 was found to play a key role in lymphocyte infiltration into the thyroid gland and the concentration of the soluble form of ICAM-1 correlates significantly with the clinical activity and treatment status in GD. We have analyzed the association of ICAM-1 polymorphisms with the age at onset of GD and the presence of ophthalmopathy. In a group of 235 patients with GD and 211 healthy controls we have shown that polymorphism at position c.721G-->A is associated with an earlier age of GD onset and that the c.1405A-->G polymorphism of the ICAM-1 gene could predispose to Graves' ophthalmopathy. This suggests that G241R and K469E amino acid substitutions in the ICAM-1 molecule could influence the intensity/duration of the autoimmunity process and the infiltration of orbital tissues. It could be speculated that therapy that modulates ICAM-1 function may delay the onset and/or prolong the remission and/or have an influence on clinical manifestations of GD.

Misoprostol and dinoprostone therapy for labor induction: a Doppler comparison of uterine and fetal hemodynamic effects.

OBJECTIVE: To compare the effect of misoprostol (PGE(1)) versus dinoprostone (PGE(2)) on blood flow in uteroplacental circulation during labor induction. STUDY DESIGN: Eighty-four women with indications for induction of labor were assigned to receive either misoprostol 50 microg per vagina every 4 h as needed or 0.5 mg doses of dinoprostone given intra-cervically every 6 h by means of a randomization table generated by computer. Doppler velocimetry of umbilical, uterine and arcuate arteries was performed immediately before and 2-3 h after the administration of misoprostol or dinoprostone. The SAS system was used to perform statistical analysis. RESULTS: There were no significant changes of pulsatility index (PI), resistance index (RI) and systolic/diastolic (S/D) ratio in umbilical arteries after both prostaglandin compounds. Vaginal application of misoprostol significantly increased all ratios in arcuate artery and S/D ratio in uterine artery. Intra-cervically dinoprostone significantly increased PI, RI and S/D ratio in arcuate and uterine arteries. CONCLUSIONS: Our results indicate that vaginal misoprostol and cervical dinoprostone administration increases uteroplacental resistance but does not affect umbilical blood flow. Misoprostol would be as safe and effective agent as dinoprostone for cervical ripening and labor induction.

[Corneal endothelium in children and adolescents with myopia]. / Sródblonek rogówki u mlodziezy z krótkowzrocznoscia.

PURPOSE: To determine, whether the myopia could has an influence on corneal endothelium morphology. MATERIAL AND METHODS: Patients' age was from 13-th to 18-th years. Lens wearers and patients with external eye diseases and ocular surgery in the history, were excluded. The endothelium was imaged by non-contact microscope Topcon SP-2000P. The following parameters were examined: corneal thickness, corneal endothelial density, mean cell area of endothelial cells, coefficient of variation of cell size. RESULTS: There were no significant differences in the corneal thickness among various degrees of myopic refractive error. Endothelial cell density (ECD) decreased in eyes with high myopia, but it not correlated either with corneal thickness nor with axial length of eyes. There was correlation between average cell area (AVG) and the degree of myopia.

Permeability of human skin to selected anions and cations--in vitro studies.

Among the many factors influencing the human body every day, metal cations and anions are some of the most important and are constantly present in atmospheric fallout. Some of them such as sulfate or nitrate anions along with different detergents may cause pathological changes within the skin. The aim of this study was to estimate whether sulfate (SO4(2-)) and nitrate anions (NO3-) as well as metal cations, magnesium (Mg2+) and calcium (Ca2+) are able to pass through isolated patches of human skin and to investigate the dynamics of ion diffusion. Concentrations of the substances corresponded to those observed in the atmospheric fallout in two regions of Poland with low (Bialowieza) and high (Katowice) pollution rate. Ion chromatography method was used to determine cations and anions levels. In vitro, we found human skin to be permeable to magnesium and calcium ions as well as sulfate and nitrate anions at concentrations observed in the atmospheric fallout in two regions of Poland having different levels of pollution. Diverse influence of sodium lauryl sulfate (SLS) detergent on the grade of metal ion permeability (acceleration in the first 10 hours of experiment) and anion permeability (lack of SO4(2-) influence) suggest the presence of different routes of ions penetration through the skin. It is also supported by different transportation characteristics of individual ions through the skin over time.