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PURPOSE: This study was conducted to develop a new optimized phacoemulsification technique for Morgagnian cataract taking into account the anatomical and topographic parameters of the lens nucleus. MATERIAL AND METHODS: A working classification of Morgagnian cataract was developed based on the size of the nucleus: if the edge of the nucleus is visualized at the upper edge of the pupil or between the upper edge and the middle of the pupil, it was classified as an initial stage of Morgagnian cataract with a large nucleus; if the upper edge of the nucleus is visualized in the middle of the pupil and below, it was classified as an advanced stage of Morgagnian cataract with a small nucleus. The first group included six patients who underwent surgery using the scaffold technique with removal of the whole small nucleus into the anterior chamber. The second group included 11 patients who underwent surgery using the scaffold technique with removal of the last fragment of the nucleus into the anterior chamber. RESULTS: The use of the scaffold technique with removal of the nucleus into the anterior chamber helped reduce the number of intraoperative complications to 16.7% in the first group, compared to 27.3% in the second group, and the percentage of endothelial cell loss to 10.1% in the first group, compared to 10.7% in the second group. CONCLUSIONS: The anatomical and topographic features of the lens and the anterior segment of the eye in Morgagnian cataract with a small nucleus allow for preliminary implantation of an intraocular lens into the capsular bag to protect the posterior capsule during phacoemulsification of the nucleus with minimal mechanical, hydrodynamic and acoustic damage to the surrounding structures of the eye.

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PURPOSE: To optimize the technique of intumescent cataract phacoemulsification by involving the use of femtosecond lasers. MATERIAL AND METHODS: Group 1 included 29 patients (30 eyes) with mature intumescent cataract, who underwent femtolaser-assisted phacoemulsification using a new, optimized technique. Group 2 included 20 patients (20 eyes), in whom the femtolaser stage was performed using the standard technique. Patients of groups 1 and 2 were almost identical in all preoperative parameters. The optimized femto-capsulorhexis technique included: preoperative assessment of intralenticular pressure, staining of the anterior capsule of the swelling lens with trypan blue, introduction of a viscoelastic with high molecular weight into the anterior chamber to balance intraocular and intralenticular pressures, increasing the laser energy when performing anterior capsulorhexis up to 10 mJ. RESULTS: In group 1, there was a non-penetration of the anterior capsule in 2 eyes, in one of them in the 30° sector, in the second - in the 45° sector. Leakage of lens material into the anterior chamber and the floating anterior capsule were not observed in patients of group 1. In group 2, non-penetration of the anterior capsule was observed in 6 eyes, in the 45-60° sector - in 2 eyes, in the 90° sector - in 3 eyes, in the 180° sector - in 1 eye. Floating anterior capsule was observed in 5 cases. Leakage of lens material into the anterior chamber was observed in 9 eyes. CONCLUSION: The optimized technique of femtolaser-assisted intumescent cataract phacoemulsification eliminates leakage of lens material into the anterior chamber and allows performing anterior capsulorhexis of given size and shape.

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Purpose - to optimize the process of phacoemulsification in patients with cataract complicated by degree I-II lens subluxation by using the scaffold technique, and to determine the indications for its application. MATERIAL AND METHODS: The patients were divided into two groups: group 1 - the main group - included 29 patients (29 eyes; 47.54%) who underwent cataract phacoemulsification with implantation of iris retractors and capsular ring using the scaffold technique. Group 2 - the comparison group - included 32 patients (32 eyes; 54.46%) who underwent cataract phacoemulsification with implantation of iris retractors and capsular ring using standard technique. RESULTS: Patients' visual acuity improved up to 0.53 (0.35; 0.80) in group 1, and up to 0.50 (0.45; 0.80) in group 2 by the time of hospital discharge. At 6 months and 1 year follow-ups, visual functions were equal, in group 1 - 0.70 (0.65; 0.80), in group 2 - 0.70 (0.60; 0.90). The number of intraoperative complications decreased from 8.20% in standard phacoemulsification to 1.64% in scaffold technique. The latter reduces endothelial cell loss by 1.95% in comparison with traditional phacoemulsification over 1 year follow-up. With the scaffold technique, the number of intraoperative complications decreased from 15.63% in group 2 to 3.45% in group 1, the number of postoperative complications - from 43.75% to 31.04%, respectively. CONCLUSION: The scaffold technique is indicated in pseudoexfoliation syndrome with weakness of zonular apparatus, degree I-II lens subluxation, in hard nucleus with absence of posterior cortical layer, in intumescent cataract, Morgagnian cataract to stabilize the posterior capsule and protect it from rupture.

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According to a prospective review study by H. Gimbel, A. Willerscheidt (1993), among 2967 cataract cases analyzed in 1991, mature intumescent cataract was observed in 34 (1.15%) patients. PURPOSE: To determine the parameters of the ocular anterior segment in patients with intumescent cataract and in their fellow eyes using ultrasound biomicroscopy (UBM) for identification of differential characteristics of intumescent cataract. MATERIAL AND METHODS: The results of preoperative diagnostic examination of the anterior segment of the eye with UBM of 21 patients (21 eyes) with intumescent cataract and their 21 fellow eyes (42 eyes in total) were analyzed. RESULTS: The mean anterior chamber depth according to UBM was 1.96±0.108 mm (from corneal endothelium), in the fellow eyes - 2.74±0.11 mm. The anterior chamber angle was 11.54±2.19°, in the fellow eyes - 20.63±4.08°. The lens thickness in the eyes with intumescent cataract was 5.26±0.13 mm, in the fellow eyes - 4.34±0.09 mm. The length of Zinn ligaments in the external, interior and superior ocular segments of the main group eyes were equal, in the inferior segments they were longer by 0.1 mm. The difference in Zinn ligament length in the eyes with intumescent cataract and fellow eyes was approximately 0.1-0.15 mm in all segments. The equatorial angle in the eyes with intumescent cataract was 32.52±0.92°, in the fellow eyes - 14.85±1.09°. CONCLUSION: A differential symptom of intumescent cataract was identified - complete spherophakia, as confirmed by a specific UBM sign: increase of the equatorial angle by 17° in comparison with the fellow eye, while the length of Zinn ligament remains equal in all segments.

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When the lens swells, a liquefied lenticular substance that increases intralenticular pressure accumulates in the lens bag making it difficult to perform standard capsulorhexis. Thus, determination of the intralenticular pressure value is of great importance for safe intumescent cataract phacoemulsification. PURPOSE: To develop a technology for intralenticular pressure measurement in patients with intumescent cataract and to construct a mathematical model for its prognosis according to preoperative examination data. MATERIAL AND METHODS: Intralenticular pressure was measured in 11 eyes with intumescent cataract. Before that, the following parameters of the anterior compartment of the eye were examined: anterior chamber depth, lens thickness according to ultrasound biomicroscopy (UBM), hypoechogenic layer (the anterior layer of liquefied lenticular masses), equatorial angle. RESULTS: The intraoperative technology of the intralenticular pressure measurement was developed. The direct dependency between thickness of the swelling lens, hypoechogenic layer value (the anterior layer of liquefied lenticular masses), anterior chamber depth and intralenticular pressure magnitude was defined. CONCLUSION: For the first time, the intraoperative intralenticular pressure was measured in patients with intumescent cataract. A dependency was defined between the thickness of the lens and the anterior layer of liquefied lenticular masses, anterior chamber depth, and intralenticular pressure magnitude; based on this, a mathematical model for intralenticular pressure measurement was constructed.

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Intumescent cataract surgery is one of the topical problems of ophthalmology. The article reviews methods of intumescent cataract diagnostics and structural features of swelling lens. Manual or femtolaser-assisted anterior continuous circular capsulorhexis and intumescent cataract phacoemulsification techniques require further research.

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Bone fractures are one of the most commonly occurring injuries of the musculoskeletal system. A highly complex physiological process, fracture healing has been studied extensively. Data from in vivo, in vitro and clinical studies, have shown pulsed electromagnetic fields (PEMFs) to be highly influential in the fracture repair process. Whilst the underlying mechanisms acting to either inhibit or advance the physiological processes are yet to be defined conclusively, several non-invasive point of use devices have been developed for the clinical treatment of fractures. With the complexity of the repair process, involving many components acting at different time steps, it has been a challenge to determine which PEMF exposure parameters (i.e., frequency of field, intensity of field and dose) will produce the most optimal repair. In addition, the development of an evidence-backed device comes with challenges of its own, with many elements (including process of exposure, construct materials and tissue densities) being highly influential to the field exposed. The objective of this review is to provide a broad recount of the applications of PEMFs in bone fracture repair and to then demonstrate what is further required for enhanced therapeutic outcomes.

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Early diagnosis of congenital glaucoma allows surgery to be performed at the stage of reversible glaucomatous alterations of the optic disc and retina. In primary congenital glaucoma, the main reason for visual acuity reduction following surgical stabilization of the intraocular pressure are corneal changes. These include an increased corneal diameter, Haab's striae, areas of thickening and a greater posterior elevation. The resultant irregular astigmatism leads to amblyopia and a marked decrease in visual acuity. Active pleoptic treatment started from a very early age in children operated on for compensated congenital glaucoma provides them an opportunity to achieve high visual acuity and full rehabilitation.

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AIM: To improve phacoemulsification technique of mature intumescent cataract and to study mechanisms of possible uncontrolled tearing of the anterior lens capsule during creation of the anterior capsulorhexis. MATERIAL AND METHODS: Two groups were formed. Group 1 consisted of 52 patients with mature intumescent cataract, in whom a two-stage capsulorhexis was performed with lenticular masses removed from the anterior and posterior capsular bag compartments in between the two stages. Group 2 consisted of 55 patients with mature intumescent cataract, whose capsulorhexis was standard. RESULTS: We have specified appropriate methods for diagnosing intumescent cataract and thoroughly investigated the mechanism of uncontrolled tearing of the anterior capsule that can occur during creation of the anterior capsulorhexis. Five structural variants of the swollen lens have been described. As to surgical complications, there were 2 cases (3.8%) of small anterior capsulorhexis tearing in group 1 that were managed by converting the capsulorhexis into the a bigger one and, thus, did not affect surgical outcomes. In group 2, there were 7 cases of uncontrolled tearing of the anterior capsule during creation of the anterior capsulorhexis, in 4 of them (7,3%) the posterior capsule got also involved. CONCLUSION: 1. It has been found that on ultrasound biomicroscopy, mature intumescent cataract is notable for a 10--15° wider equatorial angle as compared to the fellow eye, which can be regarded as spherophakia. 2. Five different structural variants of the swollen opaque lens have been described. 3. The mechanism of uncontrolled tearing of the anterior capsule during creation of the anterior capsulorhexis has been studied and the expediency of two-stage capsulorhexis with lenticular mass removal from capsular bag compartments proved.

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Changes in the energy state of biomolecules induced by electromagnetic radiation lead to changes in biological functions of irradiated biomolecules. Using the RRM approach, it was computationally predicted that far-infrared light irradiation in the range of 3500-6000 nm affects biological activity of proto-oncogene proteins. This in vitro study evaluates quantitatively and qualitatively the effects of selected far-infrared exposures in the computationally determined wavelengths on mouse melanoma B16F10 cells and Chinese hamster ovarian (CHO) cells by MTT (thiazolyl blue tetrazolium bromide) cell proliferation assay and confocal laser-scanning microscopy (CLSM). This paper also presents the findings obtained from irradiating B16F10 and CHO cells by the selected wavelengths in visible and near-infrared range. The MTT results show that far-infrared wavelength irradiation induces detrimental effect on cellular viability of B16F10 cells, while that of normal CHO cells is not affected considerably. Moreover, CLSM images demonstrate visible cellular detachment of cancer cells. The observed effects support the hypothesis that far-infrared light irradiation within the computationally determined wavelength range induces biological effect on cancer cells. From irradiation of selected visible and near-infrared wavelengths, no visible changes were detected in cellular viability of either normal or cancer cells.

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A concept of using low intensity light therapy (LILT) as an alternative approach to cancer treatment is at early stages of development; while the therapeutic effects of LILT as a non-invasive treatment modality for localized joint and soft tissue wound healing are widely corroborated. The LEDs-based exposure system was designed and constructed to irradiate the selected cancer and normal cells and evaluate the biological effects induced by light exposures in visible and infrared light range. In this study, human breast cancer (MCF7) cells and human epidermal melanocytes (HEM) cells (control) were exposed to selected far infrared light (3400nm, 3600nm, 3800nm, 3900nm, 4100nm and 4300nm) and visible and near infrared wavelengths (466nm, 585nm, 626nm, 810nm, 850nm and 950nm). The optical intensities of LEDs used for exposures were in the range of 15µW to 30µW. Cellular morphological changes of exposed and sham-exposed cells were evaluated using light microscopy. The cytotoxic effects of these low intensity light exposures on human cancer and normal cell lines were quantitatively determined by Lactate dehydrogenase (LDH) cytotoxic activity and PrestoBlue™ cell viability assays. Findings reveal that far-infrared exposures were able to reduce cell viability of MCF7 cells as measured by increased LDH release activity and PrestoBlue™ assays. Further investigation of the effects of light irradiation on different types of cancer cells, study of possible signaling pathways affected by electromagnetic radiation (EMR) and in vivo experimentation are required in order to draw a firm conclusion about the efficacy of low intensity light as an alternative non-invasive cancer treatment.

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Drug discovery and development are intense, lengthy and interdisciplinary processes. Traditionally, drugs were discovered by synthesizing compounds in time-consuming multi-step experimental investigations followed by in vitro and in vivo biological screening. Promising candidates were then further studied for their pharmacokinetic properties, metabolism and potential toxicity. Today, the process of drug discovery has been revolutionized due to the advances in genomics, proteomics, and bioinformatics. Efficient technologies such as combinatorial chemistry, high throughput screening (HTS), virtual screening, de novo design and structure-based drug design contribute greatly to drug discovery. Peptides are emerging as a novel class of drugs for cancer therapy, and many efforts have been made to develop peptide-based pharmacologically active compounds. This paper presents a review of current advances and novel approaches in experimental and computational drug discovery and design. We also present a novel bioactive peptide analogue, designed using the Resonant Recognition Model (RRM), and discuss its potential use for cancer therapeutics.

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Ataxia is a genetic neurological disorder characterised by a neurodegenerative process affecting a motor cortex responsible for balance and coordination. Recently several genes that cause autosomal dominant ataxia development were identified. These abnormal genes share a common ability to produce abnormal ataxin proteins that can affect nerve cells in the cerebellum and spinal cord. Here, using the Resonant Recognition Model (RRM) based on signal processing, we analysed ataxin proteins and identified the characteristic features corresponding to their biological activities. The RRM is a physico-mathematical model developed for analysis of protein interactions. By incorporating Smoothed Pseudo Wigner-Ville distribution (SPWV) in the RRM, we can define the active regions along the protein molecule. The results showed that our computational predictions correspond closely with the experimentally identified locations of the active/binding sites for ataxin-1 and ataxin-3 protein groups. The results obtained provide a valuable insight into the functional performance of ataxin proteins.

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It is known that cancer develops when cells in a part of the body begin to grow out of control. Because cancer cells continue to grow and divide with no order, they never differentiate into the specific tissue, and thus, they are functionally different from normal cells. However, there are some genes that help to prevent cells' malignant behavior, and therefore, are referred to as tumor suppressor genes. Here, we have investigated the structural and functional relationships of p53, oncogene and interleukin 2 (IL2) proteins using the resonant recognition model (RRM), a physico-mathematical approach based on digital signal processing methods. In addition, using the RRM concepts, we have designed the peptide analoges that would exhibit tumor-suppression-like activity and be used in anticancer vaccine development.

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Enzymes are essential for the catalysis of biochemical reactions and in the regulation of metabolic pathways. They function by greatly accelerating the rate of specific chemical reactions that would otherwise be slow. It has been shown that extremely low-power microwaves can influence enzyme activity [1-5]. This study is focused at investigating the effects of low level microwave exposures ranging from 500MHz to 900MHz on L-Lactate Dehydrogenase (LDH) enzyme activity. The results obtained revealed the increased bioactivity of the LDH upon microwave radiation at two particular frequencies 500MHz and 900MHz.

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This study is focused on experimental validation of our hypothesis proposed within the Resonant Recognition Model (RRM) [7], [8] that protein function can be modified by an applied electromagnetic radiation of defined frequency in a range of infra red (IR), visible and ultra violet (UV) light. This postulate is investigated here by applying the electromagnetic radiation (1140-1200 nm) to example of L-Lactate Dehydrogenase (LDH) protein and its biological activity is measured before and after the exposures. The presented methodology provides a possibility of enhancing the pharmaceutical and agricultural industries by amplifying drug potency via electromagnetic radiation.

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Enzymes are crucial in accelerating metabolic reactions in living organisms. Protoporphyrinogen oxidase (PpOI) is an enzyme that catalyses the production of protoporphyrin IX (PpIX), a protein used in a cancer treatment known as photodynamic therapy (PDT). In this study, a structure-function analysis of PpOI was carried out using the Resonant Recognition Model (RRM), a physico-mathematical approach for analysis of proteins interactions. This method is based on the finding that the distribution of delocalised electron energies along the protein plays a crucial role in determining the protein's biological activity. Two digital signal processing (DSP) methods were used: Fourier Transform (FT) and Continuous Wavelet Transform (CWT). Here we have determined the characteristic frequencies and the "hot spot" amino acids, and predicted the location of proteins' active site(s). Several proteins that potentially belong to the PpOI functional group were also analysed to distinguish their viability in this role.

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The aggregation status of the blood in the bulbar vessels was assessed by computer analyzer system of television images of the eye (CASTIE) in 10 patients with hypertensive angiosclerosis, 22 with diabetic proliferative retinopathy, and 15 patients without vascular abnormalities. The aggregation gradients of intravascular bloodflow in the venules were increased and aggregation coefficients in the bulbar veins decreased in the patients with vascular diseases of the retina, this indicating disorders of blood aggregation. CASTIE helps assess the degree of disorders in blood aggregation at the level of the intravascular and parietal bloodflow and single out the groups at risk of developing thrombotic complications of the retina among the patients with essential hypertension and diabetes mellitus.

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The characteristics of the contamination resulting from the Chernobyl accident are defined, as a basis for epidemiological investigations. Due to loss of integrity of the nuclear fuel and thermal buoyancy from fire and nuclear heating, a large quantity of radioisotopes were released over a period of up to 16 days. The areas affected were very large, 37 million hectares in Ukraine alone. About 5 million persons were affected in one way or another, over 2 million of them in Ukraine. For registration and follow-up of health consequences from the accident, 4 main groups were distinguished, namely: (1) the participants in the containment of the accident and its cleanup ("liquidators"); (2) evacuees; (3) residents of contaminated areas; and (4) children born to parents with significant radiation exposure. Registration and epidemiological follow-up in the former USSR and the three republics afterwards are presented with an emphasis on Ukraine. Considering the long incubation times for some of the expected illnesses and relatively low average doses, the difficulties of confirming significant effects become evident. For example leucosis morbidity among cleanup personnel within a 30 km zone around the accident was 3.4 per 100,000 before the accident and 7 per 100,000 afterwards. The question of the statistical significance of such numbers is discussed by the authors, in the context of confounding factors. For some of the observed effects it has already been established that stress and anxiety caused by the accident and living conditions in the affected areas are the principal cause rather than radiation. According to the authors, more detailed retrospective and prospective epidemiological studies are needed in the future, in order to clarify the causes of observed health effects.

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