Clinical and Molecular Characterization of Nine Novel Antithrombin Mutations

Antithrombin (AT) is the major plasma inhibitor of thrombin (FIIa) and activated factor X (FXa), and antithrombin deficiency (ATD) is one of the most severe thrombophilic disorders. In this study, we identified nine novel AT mutations and investigated their genotype-phenotype correlations. Clinical and laboratory data from patients were collected, and the nine mutant AT proteins (p.Arg14Lys, p.Cys32Tyr, p.Arg78Gly, p.Met121Arg, p.Leu245Pro, p.Leu270Argfs*14, p.Asn450Ile, p.Gly456delins_Ala_Thr and p.Pro461Thr) were expressed in HEK293 cells; then, Western blotting, N-Glycosidase F digestion, and ELISA were used to detect wild-type and mutant AT. RT-qPCR was performed to determine the expression of AT mRNA from the transfected cells. Functional studies (AT activity in the presence and in the absence of heparin and heparin-binding studies with the surface plasmon resonance method) were carried out. Mutations were also investigated by in silico methods. Type I ATD caused by altered protein synthesis (p.Cys32Tyr, p.Leu270Argfs*14, p.Asn450Ile) or secretion disorder (p.Met121Arg, p.Leu245Pro, p.Gly456delins_Ala_Thr) was proved in six mutants, while type II heparin-binding-site ATD (p.Arg78Gly) and pleiotropic-effect ATD (p.Pro461Thr) were suggested in two mutants. Finally, the pathogenic role of p.Arg14Lys was equivocal. We provided evidence to understand the pathogenic nature of novel SERPINC1 mutations through in vitro expression studies.

High penetrance of inferior vena cava system atresia in severe thrombophilia caused by homozygous antithrombin Budapest 3 variant: Description of a new syndrome

Atresia of inferior vena cava (IVC) is a rare congenital malformation associated with high risk of venous thrombosis that still has unknown etiology, although intrauterine IVC thrombosis has been suggested to be involved. The identification of IVC atresia in a case with early idiopathic venous thrombosis and antithrombin deficiency caused by the homozygous SERPINC1 c.391C > T variant (p.Leu131Phe; antithrombin Budapest 3) encouraged us to evaluate the role of this severe thrombophilia in this vascular abnormality. We have done a cross-sectional study in previously identified cohorts of patients homozygous for the Budapest 3 variant (N = 61) selected from 1118 patients with congenital antithrombin deficiency identified in two different populations: Spain (N = 692) and Hungary (N = 426). Image analysis included computed tomography and phlebography. Atresia of the IVC system was observed in 17/24 cases (70.8%, 95% confidence interval [CI]: 48.9%-87.3%) homozygous for antithrombin Budapest 3 with available computed tomography (5/8 and 12/16 in the Spanish and Hungarian cohorts, respectively), 16 had an absence of infrarenal IVC and one had atresia of the left common iliac vein. All cases with vascular defects had compensatory mechanisms, azygos-hemiazygos continuation or double IVC, and seven also had other congenital anomalies. Short tandem repeat analysis supported the specific association of the IVC system atresia with SERPINC1. We show the first evidence of the association of a severe thrombophilia with IVC system atresia, supporting the possibility that a thrombosis in the developing fetal vessels is the reason for this anomaly. Our hypothesis-generating results encourage further studies to investigate severe thrombophilic states in patients with atresia of IVC.

Principles of the perioperative Patient Blood Management

The perioperative Patient Blood Management (in Hungary National Blood Donation and Blood Saving Program) is an individualized clinical practice based on a multidisciplinary consensus with a comprehensive and complex approach. It supports the rational and judicious utilization of blood products and abolishes irrational transfusion policy. Its practical implementation is based upon three pillars: 1. anemia management without transfusion, if possible; restrictive transfusion strategy; 2. minimization of blood loss; 3. enhancement of anemia tolerance. Early detection, clarification of etiology and appropriate treatment are the most important tools for the management of preoperative anemia before surgeries with a high risk of bleeding. Minimization of blood loss can be achieved by identifying patients with congenital or acquired bleeding disorders, preparing them appropriately for surgery, discontinuing anticoagulants and antiplatelet drugs for a sufficient time in the preoperative phase of surgery and reversing their effects to comply with current guidelines. Minimal-invasive approaches are preferable. Intraoperatively, atraumatic technique and accurate topical haemostasis should be provided by surgeons. Autologous blood salvage techniques and controlled hypotension in lack of contraindications can also reduce the amount of blood loss. In cases of perioperative bleeding, protocols based on international guidelines but adapted to local circumstances must be used. Ideally, it should be managed by viscoelastic test-guided, goal-directed, individualized and factor concentrate-based algorithm. Perioperatively, an ideal oxygen demand/supply ratio must be ensured to avoid oxygen debt. Restoration and maintenance of homeostasis are essential for both the effectively functioning haemostatic system and the avoidance of oxygen deficit. Implementation of the Patient Blood Management improves patient safety, reduces the cost of medical care and facilitates the national blood product supply. Its successful introduction is our common interest. Orv Hetil. 2020; 161(37): 1554-1568.

Obstetrical aspects of the National Blood Donation and Blood Saving Program

The aims of the National Blood Donation and Blood Saving Program are to support the rational and judicious utilization of blood products and abolish irrational transfusion policy to improve patient safety. In addition to the general principles, this program has got some special obstetrical aspects. Obstetrical, especially the postpartum haemorrhages belong to the leading causes of maternal mortality worldwide. In developed countries, a trend in increasing incidence can be observed. Preparing for delivery includes some important elements such as optimization of hemoglobin level, routinely applied prophylactic or therapeutic iron supplementation and early screening and comprehensive care of patients with high risk of obstetrical bleeding. The main causes of peripartum bleeding are abruptio placentae, placenta praevia, uterine atony, retained tissue in the uterus, trauma during delivery, and haemostatic disorders or their combinations. To prevent postpartum bleeding, it is important to use the active management of the third stage of labour including prophylactic utilization of uterotonics as an essential element. Utilization of blood salvage techniques with adequate indications may be considered in cases of cesarean section or postpartum haemorhage. In cases of obstetrical haemorrhage, management of surgical bleeding has the main priority by the obstetrician. Secondary coagulopathy associated with massive bleeding should be managed by viscoelastic test-guided, individualized and factor concentrate-based algorithm, however, pregnancy-specific reference and target ranges must be used that are different from the non-pregnancy values. Obstetrical bleedings belong to the potentially preventable causes of death. Hopefully, the implementation of the National Blood Donation and Blood Saving Program in the field of obstetrics can decrease the associated morbidity and mortality further. Orv Hetil. 2020; 161(37): 1588-1598.

[Laboratory aspects of novel oral anticoagulant treatment]

The introduction of novel oral anticoagulants (NOAC) have long been expected drugs and they quickly became used widespread as their clinical effectiveness was as good as, or even better than the previously used only oral anticoagulant drug, the coumarins. Thus, the direct thrombin inhibitor dabigatran and the activated factor X inhibitors (rivaroxaban, apixaban, edoxaban) have become the part of daily therapeutic practice. Their permeation was facilitated by the guideline which suggested that no laboratory monitoring was required during NOAC treatment and this was very convenient for both patients and doctors. The clinical experience obtained in the past years, however have proved that the 'one size fits all' view is oversimplified and there are numerous situations when the determination NOAC levels is unavoidable or highly recommended. This review discusses the laboratory aspects of NOAC treatment, primarily summarizing their effect on the screening tests and special assays of hemostasis and we also describe the correct methods to determine their plasma concentrations. Orv Hetil. 2017; 158(49): 1930-1945.

Thrombin generation and low-molecular-weight heparin prophylaxis in pregnant women with thrombophilia

Pregnancy is associated with increased risk of venous thromboembolism, especially in the presence of thrombophilia. However, there is no consensus on the optimal approach for thromboprophylaxis in this population. Recent evidence suggests that thrombin generation correlates with the overall procoagulant state of the plasma. Our aim was to evaluate thrombin generation in a prospective cohort of thrombophilic pregnant women, and investigate the effectiveness of low-molecular- weight heparin (LMWH) prophylaxis in pregnancy. Women with severe (n=8), mild (n=47) and no (n=15) thrombophilia were followed throughout their pregnancies. Thrombin generation was evaluated in each trimester as well as five days and eight weeks postpartum (as a reference category). In women undergoing LMWH prophylaxis, thrombin generation and anti-Factor-Xa activity were measured just before and 4 hours after administration (peak effect). Thrombin generation was determined using Technothrombin TGA assay system. For the analysis, median peak thrombin and endogenous thrombin potential were used. Peak thrombin and endogenous thrombin potential were increased during pregnancy compared to the non-pregnant state with the highest results in the severe thrombophilia group. In women receiving LMWH prophylaxis a decrease was observed in thrombin generation at peak effect but over the progression of pregnancy the extent of this decrease reduced in a stepwise fashion. Our results show that thrombin generation demonstrates the hypercoagulable state in thrombophilic pregnancies. In addition, we found the effect of LMWH prophylaxis to progressively decrease with advancing stages of pregnancy.

Clinical and laboratory characteristics of antithrombin deficiencies: A large cohort study from a single diagnostic center

INTRODUCTION

Inherited antithrombin (AT) deficiency is a heterogeneous disease. Due to low prevalence, only a few studies are available concerning genotype-phenotype associations. The aim was to describe the clinical, laboratory and genetic characteristics of AT deficiency in a large cohort including children and to add further laboratory data on the different sensitivity of functional AT assays.

PATIENTS AND METHODS

Non-related AT deficient patients (n=156) and their family members (total n=246) were recruited. Clinical and laboratory data were collected, the mutation spectrum of SERPINC1 was described. Three different AT functional assays were explored.

RESULTS

Thirty-one SERPINC1 mutations including 11 novel ones and high mutation detection rate (98%) were detected. Heparin binding site deficiency (type IIHBS) was the most frequent (75.6%) including AT Budapest3 (ATBp3), AT Padua I and AT Basel (86%, 9% and 4% of type IIHBS, respectively). Clinical and laboratory phenotypes of IIHBS were heterogeneous and dependent on the specific mutation. Arterial thrombosis and pregnancy complications were the most frequent in AT Basel and AT Padua I, respectively. Median age at the time of thrombosis was the lowest in ATBp3 homozygotes. The functional assay with high heparin concentration and pH7.4 as assay conditions had low (44%) sensitivity for ATBp3 and it was insensitive for AT Basel and Padua I.

CONCLUSION

Type IIHBS deficiencies behave differently in clinical and laboratory phenotypes from each other and from other AT deficiencies. Heparin concentration and pH seem to be the key factors influencing the sensitivity of AT functional assays to IIHBS.

Antithrombin Debrecen (p.Leu205Pro) - Clinical and molecular characterization of a novel mutation associated with severe thrombotic tendency

INTRODUCTION

Hereditary antithrombin (AT) deficiency is a rare thrombophilic disorder with heterogeneous genetic background and various clinical presentations. In this study we identified a novel AT mutation. Genotype-phenotype correlations, molecular characteristics and thrombotic manifestations of the mutation were investigated.

MATERIALS AND METHODS

Thirty-one members of a single family were included. Clinical data was collected regarding thrombotic history. The mutation was identified by direct sequencing of the SERPINC1 gene. HEK293 cells were transfected with wild type and mutant SERPINC1 plasmids. Western blotting, ELISA and functional amidolytic assay were used to detect wild type and mutant AT. After double immunostaining, confocal laser scanning microscopy was used to localize mutant AT in the cells. Molecular modeling was carried out to study the structural-functional consequences of the mutation.

RESULTS

Unprovoked venous thrombotic events at early age, fatal first episodes and recurrences were observed in the affected individuals. The median AT activity was 59%. Genetic analysis revealed heterozygous form of the novel mutation p.Leu205Pro (AT Debrecen). The mutant AT was expressed and synthesized in HEK293 cells but only a small amount was secreted. The majority was trapped intracellularly in the trans‑Golgi and 26S proteasome. The mutation is suspected to cause considerable structural distortion of the protein. The low specific activity of the mutant AT suggested functional abnormality.

CONCLUSIONS

AT Debrecen was associated with very severe thrombotic tendency. The mutation led to misfolded AT, impaired secretion and altered function. Detailed clinical and molecular characterization of a pathogenic mutation might provide valuable information for individualized management.

Founder effect is responsible for the p.Leu131Phe heparin-binding-site antithrombin mutation common in Hungary: phenotype analysis in a large cohort

BACKGROUND

Antithrombin (AT) is a key regulator of the coagulation. In type II deficiency, the heparin-binding-site defect (type II HBS) is considered to be relatively low thrombosis risk.

OBJECTIVES

Our aims were to search for SERPINC1 mutation(s) and to describe the clinical and laboratory phenotype of a large number of AT Budapest3 (ATBp3, p.Leu131Phe) carriers and confirm the presence of a founder effect.

PATIENTS/METHODS

AT-deficient patients were recruited and carriers of ATBp3, n = 102 (63 families) were selected. To investigate the founder effect, eight intragenic single nucleotide polymorphisms, a 5'-length dimorphism, and five microsatellite markers were detected. Clinical and laboratory data of the patients were collected and analyzed.

RESULTS

In AT deficiency, 16 different causative mutations were found, and the great majority of patients were of type II HBS subtype. Most of them (n = 102/118, 86.5%) carried the ATBp3 mutation. The ATBp3 mutant allele was associated with one single haplotype, while different haplotypes were detected in the case of normal allele. The anti-factor Xa-based AT activity assay that we used could detect all ATBp3 patients with high sensitivity in our cohort. ATBp3 homozygosity (n = 26) was associated with thrombosis at a young age and conferred a high thrombotic risk. Half of the heterozygotes (n = 41/76, 53.9%) also had venous and/or arterial thrombosis, and pregnancy complications were also recorded.

CONCLUSION

In Hungary, the founder mutation, ATBp3, is the most common AT deficiency. Our study is the first in which the clinical characterization of ATBp3 mutation was executed in a large population.

Evaluation of flow cytometric HIT assays in relation to an IgG-Specific immunoassay and clinical outcome

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is a severe side effect of heparin treatment caused by platelet activating IgG antibodies generated against the platelet factor 4 (PF4)-heparin complex. Thrombocytopenia and thrombosis are the leading clinical symptoms of HIT.

METHODS

The clinical pretest probability of HIT was evaluated by the 4T score system. Laboratory testing of HIT was performed by immunological detection of antibodies against PF4-heparin complex (EIA) and two functional assays. Heparin-dependent activation of donor platelets by patient plasma was detected by flow cytometry. Increased binding of Annexin-V to platelets and elevated number of platelet-derived microparticles (PMP) were the indicators of platelet activation.

RESULTS

EIA for IgG isotype HIT antibodies was performed in 405 suspected HIT patients. Based on negative EIA results, HIT was excluded in 365 (90%) of cases. In 40 patients with positive EIA test result functional tests were performed. Platelet activating antibodies were detected in 17 cases by Annexin V binding. PMP count analysis provided nearly identical results. The probability of a positive flow cytometric assay result was higher in patients with elevated antibody titer. 71% of patients with positive EIA and functional assay had thrombosis.

CONCLUSIONS

EIA is an important first line laboratory test in the diagnosis of HIT; however, HIT must be confirmed by a functional test. Annexin V binding and PMP assays using flow cytometry are functional HIT tests convenient in a clinical diagnostic laboratory. The positive results of functional assays may predict the onset of thrombosis. © 2016 International Clinical Cytometry Society.

Progressive chromogenic anti-factor Xa assay and its use in the classification of antithrombin deficiencies

BACKGROUND

Antithrombin (AT) is a slow-acting progressive inhibitor of activated clotting factors, particularly thrombin and activated factor X (FXa). However, the presence of heparin or heparan sulfate accelerates its effect by several magnitudes. AT deficiency, a severe thrombophilia, is classified as type I (quantitative) and type II (qualitative) deficiency. In the latter case mutations may influence the reactive site, the heparin binding-site (HBS) and exert pleiotropic effect. Heterozygous type II-HBS deficiency is a less severe thrombophilia than other heterozygous subtypes. However, as opposed to other subtypes, it also exists in homozygous form which represents a very high risk of venous thromboembolism.

METHODS

A modified anti-FXa chromogenic AT assay was developed which determines both the progressive (p) and the heparin cofactor (hc) activities, in parallel. The method was evaluated and reference intervals were established. The usefulness of the assay in detecting type II-HBS AT deficiency was tested on 78 AT deficient patients including 51 type II-HBS heterozygotes and 18 homozygotes.

RESULTS

Both p-anti-FXa and hc-anti-FXa assays showed excellent reproducibility and were not influenced by high concentrations of triglyceride, bilirubin and hemoglobin. Reference intervals for p-anti-FXa and hc-anti-FXa AT activities were 84%-117% and 81%-117%, respectively. Type II-HBS deficient patients demonstrated low (heterozygotes) or very low (homozygotes) hc-anti-FXa activity with normal or slightly decreased p-anti-FXa activity. The p/hc ratio clearly distinguished wild type controls, type II-HBS heterozygotes and homozygotes.

CONCLUSIONS

Concomitant determination of p-anti-FXa and hc-anti-FXa activities provides a reliable, clinically important diagnosis of type II-HBS AT deficiency and distinguishes between homozygotes and heterozygotes.

The superiority of anti-FXa assay over anti-FIIa assay in detecting heparin-binding site antithrombin deficiency

OBJECTIVES

Antithrombin is a progressive inhibitor of active factor X (FXa) and thrombin (FIIa). Its effect is 500- to 1,000-fold accelerated by heparin or heparan sulfate. Heterozygous type I (quantitative) and most type II (qualitative) antithrombin deficiencies highly increase the risk of venous thromboembolism (VTE), while homozygous mutations are lethal. The functional defect affecting the heparin-binding site confers moderate risk of VTE to heterozygous and high risk of VTE to homozygous individuals.

METHODS

Antithrombin activity assays based on the inhibition of FIIa and FXa were compared for their efficiency in detecting heparin-binding site defects.

RESULTS

With a single exception, in heterozygotes for heparin-binding site defects (n = 20), anti-FIIa activities remained in the reference interval, while anti-FXa activities were uniformly decreased. In individuals who were homozygous for heparin-binding site mutations (n = 9), anti-FIIa activities were in the range of 48% to 80%; the range of anti-FXa activities was 9% to 25%. Anti-FIIa and anti-FXa activities in type I deficiencies and type II pleiotropic deficiency did not differ significantly.

CONCLUSIONS

Anti-FXa antithrombin assay is recommended as a first-line test to detect type II heparin-binding site antithrombin deficiency.

[Contribution focused to clarify correlation between mixtures of the free amino acids with antiglaucomatics in influencing the IOP in rabbits after application into the conjunctival sac]

PURPOSE

Correlation between the amino acid L-arginine.HCl and 3 antiglaucomatics (Timolol, Xalatan or Trusopt) mixture in their effect on the physiological IOP values in rabbits Methods: The experimental works were performed on 5 female rabbits of the New Zealand White species. After instillation of the 2 drops of in vitro prepared 10% solution of the amino acid L-arginine.HCl in 0.5% Timolol maleat (Timoptol, Zentiva), 0.005% Lanatosid (Xalatan, Pharmacia&Upjohn) or 2% Trusopt (Dorsolamid, Merc&Co.) at 8, 00 am. into the left conjunctival sac the IOP was measured before and in 15th, 30th, 60th, 120th, 180th, 240th min. and 24 hours after instillation. The right eye was used as control.

RESULTS

The amino acid 10% L-arginine.HCl solution applicated separately decreased the physiologic IOP in rabbits in confrontation with the control eyes for - 2.9 torr. The antiglaucomatics applicated separately reduced the IOP values for: 0.5% Timoptol -0,69 torr, 0.005% Xalatan -2.1 torr and 2% Trusopt -2.45 torr . The 10% L-arginine.HCl in combination with the antiglaucomatics decreased the physiologic IOP by these values: in mixture with 0.5% Timolol by -3.32 torr (16.3% compared with control, but 4.8 times lower in confrontation with 0,5% Timolol); with 0.005% Xalatan by -2.91 torr (exactly the same decrease as measured after the 0.005% Xalatan separate application); with 2% Trusopt by - 4.45 torr (23.8% compared with control, but only 1.99 times lower compared with 2% Trusopt).

CONCLUSIONS

In our experiments we applicated into the conjunctival sac in fact the already ready in vitro prepared metabolite ("bio antiglaucomatic") that can immediately penetrate the hemato-ocular barrier and enter into the target area. These experiments proved different relation between the amino acid L-arginine HCL and various antiglaucomatics. The 10% L-arginine HCL mixture with 0.5% Timoptol decreased the IOP values for more than 5x compared with Timoptol alone and mixture of the same substance with 2% Trusopt showed almost two-fold decrease (-1.99 torr, also compared with Timoptol). Comparing the L-arginine HCL mixture with 0.005% Xalatan with Xalatan alone no increased effectivity was constated. These differences in results are proving the individual specificity in influencing the IOP in rabbits by interaction of the specific amino acid in mixture with antiglaucomatics applicated into the conjunctival sac.

[The current state of the evidence of malignant tumors of the eye and its adnexa (dg. C69) in the Slovak Republic and in the Czech Republic]

The area of ophthalmooncology includes not only intraocular tumors but also adnexal and extraocular tumors, relatively rare malignancies. To get valid data and to study the incidence, diagnosis and treatment is extremely difficult. The most frequently occurring intraocular tumor in adults is malignant melanoma, in children it is retinoblastoma. We present the results of the nationwide group of patients based on the diagnosis report C69 - Tumors of the eye and adnexa according to data of the National Cancer Registry in Slovak Republic. We monitor the incidence, distribution by age group, survival and staging. In the second part of the thesis analyzed data are compared with the data from Cancer Registry in the Czech Republic. After analyzing the data, we found that the incidence of intraocular tumors have been reported to be comparable with neighbouring countries. The classification of the disease in different stages due to TNM classifying in the report is below 50 % in Slovakia. The incidence observed in each year ranges from 0.6 to 1.0 per 100 000 inhabitants. Survival of patients with dg. C69 is comparable with other countries. The proportion of clinically defined stages of the disease is in the database of Slovakia lower than in the Czech Republic. The delay of inserting data of patients in the National Cancer Registry in Slovakia and the availability of data for analysis is currently unsatisfactory. In Slovakia are available data only up to year 2003, in Czech Republic up to year 2009.

[Extrascleral overgrowth of malignant choroidal melanoma after endoresection]

OBJECTIVE

Course of progression of the malignant choroidal melanoma diagnosed in T2 stage up to stage T4 with infiltration of the orbit. Case report 41 year old patient identified with intraocular malignant melanoma in the year 2005, documentation of disease progression and disease. Access to treatment of intraocular malignant melanoma in stage T1 - T2 in the last decade has changed from a radical approach (enucleation) towards conservative treatment (brachytherapy, radiosurgical methods) or combined procedures (pars plana vitrectomy and endoresection followed by irradiation or addition of laser treatment). Currently, more than 60% of uveal melanoma is treated by brachytherapy or radiosurgical techniques and combined procedures.

CASE REPORT

A 41 years old female patient with malignant melanoma in the choroid stage T2 since 2005. The volume of the tumor was 0.9 cm³, maximal elevation was over 12 mm. The patient refused a radical treatment (primary enucleation). Due to the stage of the melanoma she was recommended to stereotactic radiosurgery and combined therapy. She underwent stereotactic radiosurgery (TDmax - total dose of 35.0 Gy) in 2005. In 2006 pars plana vitrectomy with incomplete endoresection of the tumor and silicon oil instillation was done. In 2006-2007 appeared bleeding into the anterior chamber and she underwent three times an anterior chamber lavage in another department with subsequent development of secondary glaucoma. In January 2010 patient came to our department with the local finding of malignant melanoma in stage T4 with epibulbar growth process and the infiltration of the orbit. In the period have been found two solid liver metastases. Indicated exenteration of the orbit, histopathologically confirmed mixed cell type malignant melanoma.

CONCLUSION

Progression of malignant melanoma after incomplete endoresection despite previous radiosurgical treatment can be very rapid in the course of the disease documented by ultrasound, computed tomography and magnetic resonance. The patient subsequently passed to another workplace and underwent repeated lavage of the vitreous cavity. During endoresection is opened the package fibrous mesh gateway for the infiltration process in the cavity of the orbit and epibulbar space. In the case of residual melanoma after endoresection even though the tumor was irradiated before the procedure the melanoma might progress very fast into the surrounding tissues.

[The rabbit's IOP values after instillation of the L-arginine HCL with selected antiglaucomatic drugs mixtures prepared in vitro. (comparative study of results of the experimental works)]

PURPOSE

In this work the effect by interaction in vitro free amino acid L-arginine.HCl and selected antiglaucomatic drugs prepared mixtures on the physiological IOP values in rabbits is compare.

METHODS

The experimental works were performed on 5 female rabbits of the New Zealand White species. After instillation 2 drops of in vitro prepared 10% solution of the amino acid L-arginine.HCl with antiglacoma drugs (0.5% Timoptol, 0.005% Xalatan or 2% Trusopt) alone or in double combination mixtures at 8:00 am. into the left conjunctival sac the IOP was measured before and in 15th, 30th, 60th, 120th, 180th, 240th min. and 24 hours after instillation. The right eye was used as control.

RESULTS

The amino acid 10% L-arginine.HCI solution separately decrease the physiologic IOP in rabbit's in confrontation with control eyes -2.9 torr. After antiglaucomatics separetly the decrease of the IOP were constated -0.69 torr by 0.5% Timoptol, -2.1 torr by 0.005% Xalatan, resp. -2.45 torr by 2% Trusopt. 10% L-arginine.HCl with combination of mono antiglaucomatics mixture decrease the physiologic IOP by 0.5% Timoptol -3.32 torr, by 2% Trusopt -4.45 torr, by 0.005% Xalatan only 2.91 torr. Application of 10% L-arginine-HCl in double combination of antiglaumatics decrease the physiologic IOP by 0.5% Timoptol & 0.005% Xalatan -2.96 torr, by 2% Trusopt & 0.005% Xalatan -4.32 torr and COSOPT (fixed combination of 0.5% Timolol maleat & 2% Dorsolamide.HCl) only -1.8 torr.

CONCLUSIONS

We assume that the mentioned mixtures were able to decrease the physiologic IOP in rabbits through their better penetration to the receptors of the ciliary body. The mixture of the L-arginine.HCI with antiglaucomaticum Timoptol or Trusopt, resp. double combination of Timoptol & Xalatan or Trusopt & Xalatan was twice as effective as any of the mentioned antiglaucamatic drugs used separately. We conclude that the increased effectivity of the mixtures compared with the separate components is related to the instillation of the by now ready "bioantiglaucomatic".

[Results of the IOP decrease after application of some mixtures of amino acids and antiglaucomatics in rabbits (a review of experimental publications)]

OBJECTIVE

To summarise of experimental results performed on rabbit eyes focused to influence the physiological intraocular pressure (lOP) after application of some amino acids mixture with some regularly used antiglaucomatics.

MATERIAL AND METHODS

The experiments were performed on adult rabbits (female of the New Zealand White species). The applicated substances were: 10% solution of amino acids (L-lysin.2HCl.2H2O, L-arginine.HCL or L-glycine.HCL) in antiglau-comatics 0.5% timolol (Timoptol) or 0.005% latanoprost (Xalatan). This mixture was applicated to the left eye; right eye was used as control. The measurement of IOP and pupil diameter was performed before instillation, in 15th, 30th, 60th, 180th, 240th minute and 24 hours after application.

RESULTS

Functional bioactivity of the used antiglaucomatics in case of decreased lOP is rising after interaction with the relevant specific amino acid. Glycine in timolol showed the highest effect on average decrease of the lOP physiological values (lOP decrease reached - 5,5 torr) followed by arginine in timolol (lOP decrease reached - 3,3 torr). The lOP decrease after other combinations of amino acids and antiglaucomatics was in average lower or nonsignificant.

CONCLUSIONS

Through interaction between in vitro prepared mixture free amino acids and antiglaucomatics a new, biologically active substance (metabolite) is created. After instillation in experimental condition achieving stronger and longer decrease of the lOP compared with a single antiglaucomatic or amino acid.

[Influence of spheric and aspheric IOLs on visual acuity and contrast sensitivity]

PURPOSE

To compare best corrected visual acuity and contrast sensitivity in patients with aspheric and spheric intraocular lens (IOL) after uncomplicated cataract surgery in photopic and mesopic conditions.

METHODS

38 eyes after uncomplicated cataract surgery were divided in two groups. A (18 eyes, average 69,5 +/- 6,89 years, spheric IOLs Softec 1, Lenstec, Inc. USA); B (20 eyes, average 69,47 +/- 9,44 years, aspheric IOLs Softec HD, Lenstec, Inc. USA). Follow up 3.-5. day and 4.-5. week postoperatively.

RESULTS

Best corrected visual acuity in group A was 20/23, in group B was 20/22. Contrast sensitivity in photopic conditions between group A and B were nonsignificant. Contrast sensitivity in scotopic conditions was in group B (aspheric IOLs) significant in comparison to group A (spheric IOLs).

CONCLUSIONS

Aspheric IOLs in scotopic light conditions provide patients with significant better contrast sensitivity than in patients with spheric IOLs.

[The embedded mobile orbital implant from methylmethacrylate "Hydron"--clinical and histopathological findings 25 years after implantation]

The embedded mobile hydrogel methylmethacrylate ("HYDRON" Spofa) orbital implants introduced in the beginning of 70th years of 20th century was a new method to get good cosmetic effects after enucleation. At the Dept. of Ophthalmology of the Comenius University, Bratislava, the rejection rate of this type of orbital implants in the first years after enucleation (1971-1974) was only 16.8%. This technique was applied in patients after enucleation due to traumatic phtisis of the eye globe. Authors submit a case report of a female patient from the group of implanted mobile orbital implant HYDRON implanted in 1984. They analyze clinical features and histopathological findings after surgical removement 25 years after implantation.

[Retinal and macular changes after surgical treatment of retinal detachment]

Retinal detachment represents threat not for visual acuity only, but also for visual functions at all. Successful surgery with reattachment of the detached retina is the base for the morphological revitalization with possible recovery of the retinal function. Specific changes developing during the retinal detachment are in detail analyzed using the latest technology and used as the base for selection of the most suitable surgical technique. Care should be also given to the retinal and macular changes in postoperative management of retinal detachment surgery.

Stem cell therapy: a promising and prospective approach in the treatment of patients with severe Buerger's disease

No effective blood-flow enhancement therapies are available for patients with severe peripheral arterial disease (SPAD), thus amputation remains the only option for relief of rest pain or gangrene. Autologous bone marrow-derived stem cell therapy (ABMSCT) is an emerging modality to induce angiogenesis from endothelial progenitors. A total of 5 patients with SPAD were treated by ABMSCT using isolated CD34+ cells with characterized phenotype administered by intramuscular injections. The follow-up before and 1, 3, 6, 9, and 12 months after ABMSCT was based on clinical (rest pain, walking distance without pain, nonhealing ulcers, ankle-brachial index [ABI]) and laboratory (angiography, duplex and laser ultrasonography, TcPO(2)) parameters. Significant improvement of pain and walking distance was observed in all patients. Nonhealing ulcers disappeared in 3 patients and became smaller and thinner in 1 patient. The average of ABI improved significantly on the treated limb but did not change on the contralateral limb. New collaterals were detected by angiography in 3 patients, but duplex ultrasonography detected improvement in one patient only. Laser ultrasonography showed a mild significant change, TcPO(2) values improved mainly on the foot. Severe adverse events were not observed. We conclude that ABMSCT with isolated CD34+ cells is safe, effective, and results in sustained clinical benefit for patients with SPAD.

[Intraocular pressure after instillation of amino acid arginine and combination of two antiglaucomatics (Trusopt + Xalatane mixture) in rabbits]

PURPOSE

To evaluate the effect of instilled amino acid L-arginine.HCl and combination of two antiglaucomatics (Trusopt with Xalatane mixture) on the physiological intraocular pressure IOP in rabbits.

METHODS

Into the left conjunctival sac of 5 female rabbits of the New Zealand White species was instilled the mixture of 2% Trusopt (Dorsolamidi hydrochlorici) with 0.005% Xalatane (Latano-prostum) and after the one week break, the 10% L-arginine.HCl in 2% Trusopt with 0.005% Xalatane mixture. The IOPs were measured in 0, 5, 15, 30, 60, 120, 180, 240 min. and 24 hours after the instillation. The right eyes were used as controls.

RESULTS

1. The combination of two antiglaucomatics in comparison with the control eye decreased significantly the IOP value already after 15 min. The major decrease of the IOP (6.5 mm Hg) was observed after 240 min. After 24 hours, the effectiveness was not significant. 2. After instillation of the 10% L-arginine.HCl in 2% Trusopt with 0.005% Xalatane mixture, during the next 24 hours, the biphasic decrease of the IOP was established. The maximum of the effectiveness of this mixture is after 30 min (decrease by 5.1 mm Hg). The evidence of the effect was present also after 24 hour (decrease by 2.5 mm Hg). The mean value of the IOP of the control eyes in both groups of experiments in course of 24 hours was stable and was at the initial values.

CONCLUSIONS

The combination of two antiglaucomatics (Trusopt with Xalatane mixture) was used. The effect of those two substances is not separate or additive but acts as a newly formed substance. In the structures of the eye, this new substance has only poor interaction with the free amino acids of the conjunctival sac in vivo. After in vitro interaction of the L-arginine.HCl and combination of two antiglaucomatics (Trusopt with Xalatane mixture), a new bioactive substance with stronger effect on physiologic IOP values was produced.

[Autologous bone marrow-derived stem cell therapy in patients with severe peripheral arterial disorder]

BACKGROUND AND AIMS

Amputation is the only current option for relief of rest pain or gangrene in patients with severe peripheral arterial disease. Up to now, no effective blood-flow enhancement therapies are available. Autologous bone marrow-derived stem cell transplantation is an arising therapy modality with an option of building new blood vessels through endothelial stem and/or progenitor cells.

PATIENTS AND METHODS

Five patients with severe peripheral arterial disorder were treated by autologous bone marrow-derived stem cell therapy. CD34+, CD133+ and CD45+/- cell number and ratio were determined. CD34+ cells were isolated by magnetic separation and collected into a 10 ml sample. The cell suspension was administered by local intramuscular injections (0.5-1.0 ml injections in the musculus gastrocnemius). The follow-up (before; 1, 3, 6, 9 and 12 months after the autologous bone marrow-derived stem cell therapy) based on clinical (rest pain, walking distance without pain, changes of non-healing ischaemic ulcers, ankle-brachial index) and laboratory (angiography, Color- and Laser-Doppler scan, measurement of transcutaneous oxygen tension and endothelial function test) parameters was documented and analyzed.

RESULTS

Improvement of pain and walking distance was observed in all five cases. In three cases the non-healing ischaemic ulcers disappeared, in one other case they became smaller and thinner, and in one case no change was realized. The average of ankle-brachial index improved significantly (before: 0.41, twelve months after: 0.83). New collaterals were detected by angiography in three patients, but duplex ultrasonography detected improvement in one patient only. Before and 1, 6 and 12 months after stem cell therapy the transcutaneous oxygen tension changed on the foot from 18.80/16.78/23.83/37.50 mmHg, and on the calf from 36.66/31.25/45.00/37.30 mmHg. The macro- and microcirculation parameters did not show improvement after 1 month, however, after 3, 6, 9 and 12 months improved parameters were recorded. Severe adverse events were not observed. In one case elevated level of serum creatinine phosphokinase, and in another case a mild form of vasculitis were detected.

CONCLUSION

autologous bone marrow-derived stem cell therapy with isolated CD34+ cells is effective, safe and results in sustained clinical benefit for patients with severe peripheral arterial disease.

[Intraocular pressure (IOP) in rabbits after application of amino acids taurine and arginine with betablocker timolol]

PURPOSE

To assess the efficiency of the antiglaucomatic 0.5 % Timolol mixture with two amino acids: (1) 10% L-taurine and (2) 10% L-arginine on the physiological IOP in rabbits.

METHODS

Into the left conjunctival sac of 5 adult female rabbits of the New Zealand White species was instilled (a) 0.5% Timolol alone; (b) the mixture of 10 % L-arginine and 10% L-taurine in aqua pro injectione; (c) the mixture of 10% L-arginine and 10% L-taurine in 0.5% Timolol. The IOP was measured before and 5, 15, 30, 60, 120, 180, 240 min., and 24 hours after the instillation. The right eye was used as control.

RESULTS

(a) The mixture of the amino acids arginine and taurine in Timolol achieved significant IOP decrease in rabbits (except results at 5 min. and 24 hours after instillation) in all measured times with the maximum in 120 and 180 min. showing the biphasic character of the IOP decrease; (b) the mixture of amino acid taurine and arginine reached the border of significance (p < 0.05). The IOP decrease showed biphasic character, with the maximum in 60 min. (decrease of 3.8 mm Hg) and in 120 min. (decrease of 3.3 mm Hg); (c) the antiglaucomatic drops 0.5% Timolol alone decreased the IOP values without significance comparing with the control eye. The maximum decrease was measured in 120 min. (2.9 mm Hg).

CONCLUSIONS

The mixture of amino acids taurine and arginine in 0.5% Timolol proved significant decrease of the IOP physiological values in rabbits. The maximum decrease was achieved 120, 180 min., and 24 hours after the instillation. The average value of the decrease 24 hours after instillation, compared with the control eye, was 3.2 mm Hg.

[Effect of the mixture of timoptol and amino acid taurine in the bioregulation of the intraocular pressure in rabbits]

PURPOSE

To examine the effectivity of the antiglaucomatic Timoptol mixture with amino acid L-taurine.HCl on physiological values of the IOP in rabbits.

METHODS

The experimental work was performed on 5 female rabbits of the New Zealand White species. Into the left conjunctival sac at 800 was applicated: a) the 10% L-taurine.HCl in 0.5% Timolol; b) the 0.5% Timolol alone; c) the 10% L-taurine.HCl alone. The IOP was measured before and in 5th, 15th, 30th, 60th, 120th, 180th and 240th min. and 24 hours after the instillation. The right eye was used as control.

RESULTS

a) The 10% L-taurine.HCl in 0.5% Timolol showed also significant IOP decrease (without 5th min.) in all measured times with maximum in 180th min. (with value of decrease 6.7 torr) and in 24th hours the decreased showed still significantly lower level - 3.3 torr; b) The antiglaucomatic 0.5% Timolol alone decreased the IOP values compared with the control eye without significance. The IOP values from the 60th min. were nearly linear character (the mean decrease compared with the control eye was only 1 torr); c) The 10% amino acid L-taurine.HCl showed in all measured times only no significant decrease of the physiological IOP.

CONCLUSIONS

The results proved that in the mixture of antiglaucomatic Timoptol and amino acid Taurine a new biologically active substance, the bioregulator is created by interaction. This metabolite as "bioantiglaucomatic" showed several times higher effect on the IOP decrease compared with Timolol or Taurine alone. The showed effect on IOP based on interaction of amino acid mixture with antiglaucomatic is specific and efficacy together with duration changed according the type of amino acid.

[Control of the rabbit's IOP after topic instillation of antiglaucomatic latanoprost and amino acid arginine with lysine mixture]

PURPOSE

To evaluate the effect of locally instilled 10% L-arginine.HCI and 10% L-lysine.2HC1.2H20 in 0.005% Latanoprost (Xalatane) mixture on the physiological IOP in rabbits.

METHODS

After instillation of the arginine and lysine in 0.005% latanoprost mixture into the left conjunctival sac of 5 female rabbits of the New Zealand White species the, IOP was measured at the time of instillation, and 5, 15, 30, 60, 120, 180, 240 min. and 24 hours after the instillation. The right eye was used as the control.

RESULTS

The mixture of arginine with lysine in 0.005% latanoprost decreased significantly the IOP value. The decrease had two peaks. The major decrease of the IOP was observed after 30 min. (3.1 mmHg) and after 24 h (5.0 mmHg) after instillation of this mixture. Between 120 min. and to 240 min., the mild decrease of the mean value of the IOP was found at the control eye as well.

CONCLUSIONS

The mixture of arginine with lysine in 10 % concentration in 0.005 % latanoprost (Xalatane) decreased significantly the physiological IOP values in rabbits during the whole experiment. The decrease was significant in comparison both to the IOP of the control eye and to the effect of the amino acids arginine and lysine alone.

[Changes of the physiological intraocular pressure (IOP) values after the application of latanoprost and amino acid glycine mixture in rabbits]

PURPOSE

The influence of the mixture of amino acid 10% L-glycine.HCl and antiglaucomatic 0.005% Latanoprost (XALATAN) on the physiological IOP values in rabbits is evaluated in this paper.

METHODS

Experiments were performed on 5 female rabbits of the New Zealand White species. The 0.005% Latanoprost alone, the 10% L-glycine.HCl alone and the mixture of 10% L-glycine.HCl in 0.005% Latanoprost were instilled into the left conjunctival sac. The IOP and pupillary diameter were measured before, and 5, 15, 30, 60, 120, 180, 240 minutes and 24 hours after the instillation. The right eye was used as control.

RESULTS

a/ after the instillation of the 0.005% Latanoprost, the significant decrease of the physiological IOP in rabbits was found 5, 15, and 30 min after the application. Maximal decrease (by 33.6%) was measured after 30 min. In the period from 60 to 240 min., the IOP decrease occurred also in the control eye; b/ decrease of the IOP after the instillation of the amino acid L-glycine.HCl (10% concentration) has no significant value; after 15, 30 and 60 min, the IOP decreased also in the control eye; c/ after the instillation of the 10% L-glycine.HCl and 0.005% Latanoprost mixture the physiological IOP showed no significant decrease during 24 hours. The physiological IOP values of the control eyes during this experiment remained unchanged.

CONCLUSIONS

The effect of the mixture of 10% amino acid L-glycine.HCl in 0.005% Latanoprost on the decrease of the physiological IOP values in rabbits was not significant. The average decrease of the IOP value was the same as the non-significant decrease of the individual components.

[The effect of glycine with timoptol on the rabbit IOP physiological values]

PURPOSE

the mixture of 10% L-glycine.HCl in 0.5% Timoptol, intensity and duration of effect on the physiological IOP is evaluated in this work.

METHODS

Experiments were performed on 5 rabbits of the New Zealand White species. The mixture and its components were individually instilled into the left conjunctival sac. The right eye was used as control.

RESULTS

after instillation of the 10% L-glycine.HCl and 0.5% Timoptol mixture the IOP showed significant decrease compared with the control eye during 24 hour evaluation. Maximal decrease for 33% (8.5 torr) was measured in 60th min., compared with the decrease for 30.5% (7.6 torr) in 120th and for 28% in 30th min. On the contrary, both substances alone--the 10% L-glycine.HC1 and 0.5% Timoptol decrease the physiological IOP values only no significantly compared with their mixture and the control eyes. The mean value of the pupilar diameter was 7.8 mm on both eyes.

CONCLUSIONS

We assume that the decrease of the physiological IOP value is caused by a new metabolite--the "bioantiglaucomatic" created by interaction of glycine and Timoptol in vitro. The effect of this mixture on the decrease of the physiological IOP values is 8-times stronger compared with Timoptol and 4.3-times stronger compared with glycine. Application of such already prepared bioantiglaucomatic in the clinical practice can contribute to the more effective, safe and reliable therapeutic effect on the IOP in glaucomatic disease.

[Reduction of the physiologic IOP value after instilation of the mixture of the 2 amino acid's (L-lysine and L-arginine) in timoptol--experiment on rabbit's]

To evaluate influence of mixture of the 2 amino acids (L-arginine-HCL and L-lysi-ne.2HCL.H2O) in the antiglaucomatic--beta-blocker Timoptol--on the physiologic intraocular pressure (IOP) in rabbits (experiment).

METHODS

The mixture of 10% L-lysine.2HCL.H2O + 10% L-arginine.HCL in 0.5% Timoptol was instilled into the left conjunctival sac of the 5 adult rabbit's (female of the New Zealand White species) and the right eye was used as control. The IOP and pupilar diameter were measured before and in 5th, 15y th, 30th, 60th, 120th, 180th and 240th min. and 24 hours after the instillation.

RESULTS

The experimental results proved that the non-selective beta-blocker Timoptol interacts at the same time with two amino acids. The mixture of 10% L-lysine.2HCL.H2O + 10% L-arginine.HCL in 0.5% Timoptol decreased the physiologic IOP in two phases. The first phase started from application up to 15th min. In this period parallel IOP decrease occurred also in control eye (with no significant difference). The second phase started in 30th min. after the instillation and lasted until the end of experiment. In this phase the control eye IOP remained linear after the initial over the baseline increase. The eye with instilled mixture showed significant IOP decrease (p < 0.01). Maximum difference between the two IOP's was measured in the 180th (7.3 mmHg; 35.4%). From this moment IOP slightly increased up to the 24th hour showing still significantly lower level--5.0 mmHg (24.3%) compared with the control (p < 0.01).

CONCLUSIONS

Results proved that in the mixture of 10% L-lysine.2HCL.H2O + 10% L-argi-nine.HCL in 0,5% Timoptol a new substance, the "specific bioantiglaucomatic" is created by interaction. Compared with the substances alone, mixture of the 2 amino acids in the antiglaucomatic decreased the physiologic intraocular pressure (IOP) in rabbits (experiment) with high significance for 24 hours.

[Changes of physiological intraocular pressure (IOP) in rabbits after administration of the amino acid lysine and the antiglaucoma drug latanoprost (Xalatan)]

PURPOSE

To show and underline specific character of influence of the mixture of 10% L-lysine.2HCl.2H2O in 0.005% latanoprost on physiological levels of IOP.

METHODS

The mixture of 10% L-lysine.2HCl.2H2O in 0.005 % latanoprost (Xalatan), or separately 0.005 % latanoprost and 10% L-lysine.2HCl.2H2O respectively were in weekly intervals instilled into the conjunctival sac of the left eye of five rabbits (females of "New Zealand white" bred). The IOP levels and the size of the pupil were measured in minute 5, 15, 30, 60, 120, 180, and 240 after the instillation. The right eye was considered as a control.

RESULTS

The amino acid L-lysine.2HCl.2H2O by itself did not influence the IOP or the size of the pupil; latanoprost until minute 30 lowered the IOP, in minute 55 exceeds the IOP the level of the control eye. Since minute 60 until 240, the IOP changed irregularly and insignificantly. The mixture of 10% solution of L-lysine.2HCl.2H2O in latanoprost 0.005% insignificantly lowered the IOP until min. 30, after rapid elevation in min. 50 exceeds the IOP of the control eye, and since min. 60, the IOP remains above the control eye's IOP with the same course of levels.

SUMMARY

The amino acid L-lysine.2HCl.2H2O alone did not change the physiological IOP. Latanoprost 0.005% significantly lowered the IOP until min. 30. High level of interactive specificity as well as duration of influence of the mixture of respective amino acid with respective antiglaucomatic drug was established.

[The rabbit IOP and pupil values after application of aminoacid L-lysine and antiglaucomatic Timoptol mixture]

OBJECTIVE

In this article authors focused to influence the physiologic IOP values after application of the aminoacid 10% L-lysine.2HCl.2H2O in 0.5% Timoptol eye drops mixture in experiments.

METHODS

0.5% Timoptol, followed by 10% L-lysine.2HCl.2H2O and mixture of 10% L-lysine.2HCl.2H2O with 0.5% Timoptol was instilled weekly into the left conjunctival sac of 5 adult rabbits (females of the New Zealand White species). The IOP and pupilar diameter were measured in 5, 15, 30, 60, 120, 180 and 240 min. after instillation. The right eye was used as control.

RESULTS

In experiments authors observed that: a) the aminoacid 10% L-lysine.2HCl.2H2O is without influence on the physiologic value of the IOP; b) 0.5% Timoptol compared with control eye nonsignificantly decreased the rabbit IOP; c) after instillation of 10% L-lysine.2HCl.2H2O and 0.5% Timoptol mixture the IOP showed decrease of the physiologic IOP in two periods. The initial non-significant period of the IOP decrease was measured after application up to the 60th min. The identical values were also in the control eye. However, the major decrease of the IOP compared with control eye was observed during the second period starting from 60th min. up to the end of experiments (to the 4th hour) after instillation of this mixture. The mean value of this significant decrease was 3.3 torrs of the physiologic IOP value showing regular and linear effectivity in the experimental eye. In the control eye the second period was without decrease of the IOP.

CONCLUSIONS

The results demonstrate that the Timolol alone decreased the physiologic IOP no significantly, the aminoacid L-lysine.2HCl.2H2O is without influence on the physiologic value of the IOP. In experiments we confirmed that in a mixture of aminoacid L-lysine.2HCl.2H2O with antiglaucomatic 0.5% Timoptol a new substance was created, a new "bio-antiglaucomatic", responsible for more significant decrease of the physiologic IOP.

[IOP in rabbits after instillation of a mixture of the antiglaucomatic Cosopt and the aminoacid L-argininin HCL into the conjunctival sac]

OBJECTIVE

The article documents results of experiments focused to influence the physiological IOP values after application of the COSOPT eye drops (double combination of bbb-blocker and carbonic anhydrase inhibitor), aminoacid 10% L-arginin.HCl and their mixture in rabbits.

METHODS

COSOPT followed by 10% L-arginin.HCl and mixture of 10% L-arginin.HCl with COSOPT was instilled weekly into the left conjunctival sac of 5 adult rabbits (females of the New Zealand White species). The IOP and pupilar diameter were measured in 5, 15, 30, 60, 120, 180, 240 min. and 24 hours after instillation. The right eye was used as control.

RESULTS

The antiglaucomatic COSOPT no significantly decreased the rabbit IOP during 24 hours (mean value 1.85 %) in vivo. The aminoacid 10% L-arginin.HCl achieved significant decrease of the IOP: the mean value was 16.03% reaching maximum in 60th and 180th min. After instillation of the 10% L-arginin.HCl and COSOPT mixture in the IOP showed significant decrease with mean value of 9,64% (except values in 5th min. and 24th hour). Compared with control eye, the major decrease of the IOP was measured in 240th min. (mean value 17.98%). However even in 24 hours after instillation the IOP was not reaching the values of the control eye, shoving also the IOP decrease.

CONCLUSION

We assume that in a double combination of antiglaucomatics in COSOPT a new substance was created. This substance interacted in vitro with the aminoacid 10% L-arginin.HCl resulting in a new "bio-antiglaucomatis" better penetrating into the target area. This new substance was responsible for more significant decrease after the mixture application compared with COSOPT alone. The presence of aminoacid can slow down the undesirable effect of the antiglaucomatics together with the possible neuroprotection.

[Reaction of the physiological IOP in rabbits after application of the latanoprost (Xalatan) and amino acid L-arginine HCl mixture]

Authors present results of series of experiments focused to influence the IOP by antiglaucomatics in rabbits (New Zealand White) with physiological IOP. Adding of the 10% amino acid L-arginine x HCl to the 0.005% Xalatan eye drops intensifies activity of antiglaucomatics resulting in 9.5% average reduction of the IOP in a four-hour experiments (with maximum in 15th min.--19.3%), compared with application of both substances alone. Size of the pupil was not affected. Based on our experimental results we assume that the increased activity of the 0.005% Xalatan mixture with 10% amino acid L-arginine x HCl created a new complete metabolite--"bio-antiglaucomaticum". According to our observations this metabolite caused increase of the uveo-scleral outflow leading to the striking reduction of the physiological IOP in rabbits.

[Reduction of astigmatism after perforating keratoplasty by adjustment of single running sutures and its influence on visual acuity]

The authors assess the outcomes of postkeratoplasty single running suture adjustment in 14 eyes (16 adjustments) of 14 patients (4 women, 10 men). The average age of patients was 39.68 year (ranging from 19 to 70 years). The suture adjustment was done in time span 2 to 39 weeks following after perforating keratoplasty (PKP), average 7.5 weeks. Follow up time was from 1 to 12 months, average 10.8 months. The value of keratometric and topographic astigmatism before suture adjustment were compared to the value of keratometric and topographic astigmatism 1, 6 and 12 months after suture adjustment. The changes of corneal refractive power and changes of uncorrected and best-corrected visual acuity were noticed as well. The mean value of keratometric astigmatism 7.47 +/- 2.69 D and mean topographic astigmatism 7.75 +/- 3.25 D before suture adjustment was decreased to 4.92 +/- 2.41 D and 4.83 +/- 1.46 D respectively one month after suture adjustment. These reductions of keratometric and topographic astigmatism (2.55 D and 2.92 D respectively) were statistically significant (p = 0.0416, and p = 0.0211 respectively). The mean keratometric astigmatism was still significantly lower (p < 0.05) after 6 and 12 months after suture adjustment in comparison to status before suture adjustment. In assessment of topographic changes we noticed small continuous increasing of astigmatism (1.27 D after 6 months and 0.2 D after 12 months after suture adjustment). These changes of topographic astigmatism were not statistically significant. The changes of mean corneal refractive power were not statistically significant as well. The mean uncorrected visual acuity increased significantly (from 0.13 to 0.34, p < 0.05) 1 month after suture adjustment. This improvement of uncorrected visual acuity was not significant after 6 and 12 months after suture adjustment. The best-corrected visual acuity improved from 0.37 to 0.61 after one month after suture adjustment but was not statistically significant and stayed still at the same level with minimal changes during follow up time.

[Comparison of the effectiveness of a mixture of 10% L-arginine and HCl combined with 0.5% Timoptol and with 2% Trusopt: and the individual components on intraocular pressure in an experiment on rabbits]

The presented experimental work is focused to examine effectivity of the amino acid 10% L-arginine x HCl mixture with antiglaucomatic--2% Trusopt (carbonic anhydrase inhibitor) and with 0.5% Timoptol (non-selective beta-blocker) and of the each single compound on intraocular pressure (IOP). In the group of 5 rabbits (New Zealander White) with physiological levels of IOP already the single amino acid L-arginine x HCl decreased the IOP (for 18.4% compared with 0.5% Timoptol and for 9.7% with 2% Trusopt). In case of mixture with the mentioned antiglaucomatics the L-arginine x HCl significantly increases their activity. The showed results indicate the presence of the free amino acids and their interaction with the adequate antiglaucomatic is required for correct action. Based on this interaction a new bio-active metabolite is created (possibly called as "bio-antiglaucomatic").

[Intraocular pressure in rabbits after administration of 10% L-arginine HCl in 2% Trusopt]

In this contribution publish the observation that addition of 10% L-arginin.HCl to the 2% Trusopt eye drops intensifies activity of antiglaucomatics with an important reduction of the normal intraocular pressure (IOP) in rabbits New Zealand white namely from 15 up to 240 minutes, compared with application of both substance alone. Size of the pupil was not affected. Based on our experimental results we assume that this increasing activity of Trusopt mixture with amino acid L-arginin.HCl created a new metabolite. According to our observations this metabolite caused reduction of the humor aqueous production and together with the increased of the uveo-scleral outflow leads to the striking reduction of the IOP.

[Lingual thyroid]

Lingual thyroid is a rare embryological aberration with incidence of 1:100,000. It is an ectopic thyroid tissue. In most cases, it is diagnosed in childhood and young adulthood but frequently around menopause. It appears as a mass on the base of the tongue causing mostly local symptoms often with hypothyroidism, rarely with thrive and mental retardation. Authors describe the features, diagnosis and therapy of lingual thyroid with the case of a 23-year-old woman. They analyze the probable pathomechanism and potential risk of malignant transformation of lingual thyroid. In this case, the diagnosis was described at the age of 17, but therapy or further investigation did not take place then. Six years later the patient visited our surgery with local complaints in euthyroid phase. Since the suppression therapy proved to be unsuccessful, the problem was finally solved by operation.

[A combination of timoptol and L-arginine HCl: a regulator of intraocular pressure in rabbits]

In our experimental study were determined changes IOP an pupil after application mixture of aminoacid 10% L-arginine.HCl in 0.5% Timoptol into the conjunctival sac of left eye of 5 healthy albinotic rabbits (the New-Zeland White species). The right eye was control. Our results proved that the mixture of 0.5% Timoptol with 10% L-arginine.HCl has significantly decreases IOP against the control eye during the whole experiment. The maximum of decrease IOP was reached in 60th min. (20.1%; 4 torr) and in 240th min. (10.7%; 2.1 torr). In comparison with effect of mixture of both compartments, the 10% L-arginine.HCl and 0.5% Timoptol applicated alone caused only non-significant IOP decrease. Papilar diameter in both eyes were identical (7-7.5 mm) during the whole experiment. We suggest that the interaction of L-arginine.HCl with Timoptol causes formation of the new metabolite which is, in fact already effective component; this new substance decreases production of aqueous humor of corpus ciliare and the IOP is decreased in this way in physiological conditions. Utilization of this knowledge in clinical conditions could contribute to better utilization and more harmless use of antiglaucomatics in glaucoma disease therapy. For that reason, more longtime studies should be performed to evaluate the effect of this new metabolite in local application.

[Physiologic significance of the interaction between timolol and free amino acids in eye structures]

The authors analyze the interaction of timolol maleate (Timoptol, Léciva Prague) with free amino acids with regard to the effect on intraocular pressure. The different colour reaction of an amino acid mixture with Timoptol, the decline of radioactivity of Na[I125] tyrosine with Timoptol and the formation of 8 radioactive fractions after addition of Timoptol to Na[I125] indicate: a) the specificity of interaction of each amino acid with Timoptol; b) suggest that between Timoptol and free amino acids a firm covalent bond develops with the concurrent development of a new biologically active metabolite. Evidence of the presence of a new metabolite is important from the aspect of understanding and more accurate definition of the action of Timoptol in tissue structures of the eye and thus also for possible effective treatment of glaucoma.