Surgical treatment of damage to the posterior capsule of the lens after laser vitreolysis

Damage to the posterior capsule of the lens after laser vitreolysis causes the formation of traumatic cataracts and a decrease in visual acuity. The search for surgical methods of treating such complications is relevant. Purpose. To develop and improve the technique of posterior capsulorexis during phacoemulsification and implantation of IOL combined with vitrectomy in the presence of an initial injury of the posterior lens capsule. Material and methods. Clinical case - a patient came to the clinic with complaints about a decrease in visual acuity and quality after laser vitreolysis performed in another clinic. Observed the damage of the posterior capsule of the lens. The operation was performed according to the developed technique. Results. A method of primary posterior capsulorexis during phacoemulsification and implantation of IOL after vitreolysis, combined with vitrectomy, is proposed. Achieved high visual acuity after the operation, OD=1.0. Conclusions. 1) The developed technique of primary posterior capsulorexis is safe and allows partially preserving the posterior capsule of the lens, while forming a «window» in the area of damage, and implanting the IOL into a capsule bag. 2) The installation of scleral ports during primary posterior capsulorexis makes it possible to successfully combine this operation with vitrectomy and prevent the displacement of lens fragments to the fundus. Key words: сataract, posterior capsulorexis, laser vitreolysis, phacoemulsification, pseudophakia, IOL, vitrectomy, vitreous body.

STUDYING THE POSSIBILITY OF USING POLYETHYLENE OF SEPARATE GRADES (TYPES) FOR THE MANUFACTURE OF TRANSPORT CAPSULES NECESSARY FOR THE PERFORMANCE OF NEUTRON ACTIVATION ANALYSIS ON SHORT LIVING ISOTOPES

To replenish a specific consumable material, experimental samples of transport capsules were made, intended for neutron activation analysis for short-lived isotopes. The correspondence of the manufactured capsules to the real conditions of their transportation has been studied. The study of the elemental composition of the capsule material has been carried out. Analysis of the spectra of induced activity showed the presence of metal impurities in polyethylene, which must be taken into account when performing neutron activation analysis.

Pangasius Fish Skin and Swim Bladder as Gelatin Sources for Hard Capsule Material

In this paper, we report the extraction and characterization of gelatin from the abundant industrial fishery waste of Pangasius skin and swim bladder and its application as the base material for hard capsule shells. The yield of gelatin ranged between 19 and 23%, content of moisture is 7.6–9.2%, ash is 1.1–1.7%, pH is 4.1–5.2, gel strength is 238–278 bloom, and viscosity is 65–74.7% mP. SDS-PAGE showed all gelatins have chains of α1, α2, and β-peptides. The skin, swim bladder, and mixed gelatins were successfully used in the production of hard capsule shells. The dimensions, weight, disintegration time, and water content properties of the hard capsules from these Pangasius wastes were akin to the standards of commercial capsules.

Highly Efficient Encapsulation of Ingredients in Poly(methyl methacrylate) Capsules Using a Superoleophobic Material

Increasing the efficiency of encapsulation of ingredients into spherical capsules can decrease the manufacturing costs of the capsules. Ingredients can be encapsulated with high efficiency (>99%) into nondegradable hard resin capsules prepared by polymerization of spherical droplets of trimethylolpropane trimethacrylate (TRIM) monomer placed on a superoleophobic material. Poly(methyl methacrylate) (PMMA) resin is a more versatile capsule material than poly-TRIM resin. In this study, the efficiency of encapsulation in PMMA resin capsules prepared from methyl methacrylate (MMA) monomer was investigated. To reduce the volatility of the MMA monomer, pre-polymerized MMA was used for capsule preparation. Although non-volatile α-tocopherol and doxorubicin could be encapsulated in the capsules with high efficiency by heat polymerization at 60°C for 3 h, the efficiency for volatile tetradecane was much lower (approximately 60%) because it evaporated. Furthermore, even when using pre-polymerized MMA, more than 70% of the prepolymer evaporated during polymerization. To prevent the evaporation of tetradecane and the prepolymer, ultraviolet photopolymerization was adopted because it was faster and could be conducted at a lower temperature. The photopolymerization prevented the evaporation of the prepolymer and increased the efficiency of encapsulation of tetradecane (approximately 90% efficiency). This polymerization system is effective for encapsulation of ingredients in PMMA capsules with high efficiency.