Развитие аптечного дела в Городокском районе Витебской области

ИСТОРИЯ МЕДИЦИНЫИСТОРИЯ ФАРМАЦИИПЕРВАЯ ПОМОЩ

Reactive combinatorial synthesis and characterization of a gradient Ag-Ti oxide thin film with antibacterial properties

The growing demand for orthopedic and dental implants has spurred researchers to develop multifunctional coatings, combining tissue integration with antibacterial features. A possible strategy to endow titanium (Ti) with antibacterial properties is by incorporating silver (Ag), but designing a structure with adequate Ag+ release while maintaining biocompatibility has been shown difficult. To further explore the composition-structure-property relationships between Ag and Ti, and its effects against bacteria, this study utilized a combinatorial approach to manufacture and test a single sample containing a binary Ag-Ti oxide gradient. The sample, sputter-deposited in a reactive (O-2) environment using a custom-built combinatorial physical vapor deposition system, was shown to be effective against Staphylococcus aureus with viability reductions ranging from 17 to above 99%, depending on the amount of Ag+ released from its different parts. The Ag content along the gradient ranged from 35 to 62 wt.%, but it was found that structural properties such as varied porosity and degree of crystallinity, rather than the amount of incorporated Ag, governed the Ag+ release and resulting antibacterial activity. The coating also demonstrated in vitro apatite-forming abilities, where structural variety along the sample was shown to alter the hydrophilic behavior, with the degree of hydroxyapatite deposition varying accordingly. By means of combinatorial synthesis, a single gradient sample was able to display intricate compositional and structural features affecting its biological response, which would otherwise require a series of coatings. The current findings suggest that future implant coatings incorporating Ag as an antibacterial agent could be structurally enhanced to better suit clinical requirements. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.Peer ReviewedPostprint (author’s final draft

Antibacterial Properties of Dental Luting Agents: Potential to Hinder the Development of Secondary Caries

A modified direct contact test was used to evaluate the antibacterial properties of four commercially available dental luting agents (RelyX Unicem, Ketac Cem, Ceramir Crown & Bridge and Harvard Cement) and two reference materials (glass-ionomer cement and calcium aluminate cement) compared to a negative-control material (PMMA). Streptococcus mutans bacteria were placed in direct contact with specimens that had been aged for 10 min, 1 day, and 7 days, in order to test the antibacterial properties of the materials. A metabolic assay containing resazurin was used to quantify the amount of viable bacteria remaining after the direct contact tests. The effects of pH and fluoride on bacteria proliferation were also evaluated. Strongest antibacterial properties were found for calcium aluminate cement, followed by Ceramir Crown & Bridge and RelyX Unicem. Ketac Cem, Harvard Cement, and the reference glass-ionomer cement showed bacteria content either higher than or not significantly different from the PMMA control in all instances. pH levels below 6.3 and above 9.0 were found to have negative effects on bacterial proliferation. No correlation between either acidic materials or fluoride release and antibacterial properties could be seen; rather, basic materials showed stronger antibacterial properties

Ankomstkontroll av TFT-displayer

Displays to be used in display computers for vehicles and machines in critical environments shall be possible to inspect regarding pixel defects. The main part of the goal was to realize a test equipment so that different colours can be visualized on displays of different resolutions and interfaces, with a minimum startup time. The inspection of the displays will be visual. One pixel is consisting of three sub-pixels: red, green and blue, each controlled by a Thin Film Transistor (TFT). If some TFTs are broken, different types of pixel defects occur. There is an ISO standard defining classes for how many defects of each type that can exist on a display before it should be replaced by the supplier. But other limits can be agreed between supplier and customer. To be able to see the different types of pixel faults, 5 different colours should be shown on the display: red, green, blue, black and white. A list was supplied containing 10 different models of display elements for which tests should be possible. They were thoroughly analyzed regarding their technical data for resolution and interfaces for backlight and video signals. The displays are of 3 different resolutions. 5 displays have backlight of the older technology Cold Cathode Fluorescent Lamps (CCFL) which means neon light from tubes, while 5 have the later technology Light Emitting Diodes (LED). 2 of the displays receive the video signals in parallel, while 8 receive them via Low Voltage Differential Signaling (LVDS). The LVDS connector showed to have a special pin configuration for 2 of the 8 LVDS displays. This was the most important discovery, because if the standard LVDS cable would have been used from the carrier board, the displays would probably have been damaged. Because of these differences different types of boards and cables had to be used, both standard parts and modified, to be able to supply the different display models with backlight and video signals. To achieve the main part of the goal an existing display computer was modified and used as the base platform for a prototype test equipment. All signaling to the display had to be generated by the FPGA instead of the CPU module. The FPGA project was written in VHDL language. The project included six different modules of which some were written from scratch, some were reused and some were partly reused from an already existing FPGA project. Display resolution is set with a jumper and the 5 colours are visualized in a loop, using a push button

Antibacterial Strategies for Titanium Biomaterials

Titanium and titanium based alloys are widely used in dentistry and orthopedics to replace hard tissue and to mend broken bones. It has become a material of choice due to its low density, high strength, good biocompatibility and its capacity to integrate closely with the bone. Today, modern materials and surgical techniques can enable patients to live longer, and aid in maintaining or regaining mobility for a more fulfilling life. There are, however, instances where implants fail, and one of the primary causes for implant failure is infection. This thesis deals with two possible ways of reducing or eliminating implant associated infections; TiO2 photocatalysis, where a surface can become antibacterial upon irradiation with UV light; and incorporation of silver, where a subsequent release of silver metal ions result in an antibacterial effect. For the TiO2 photocatalysis strategy, a simple and cost effective chemical oxidation technique, using hydrogen peroxide (H2O2) and water, was used to create an active TiO2 surface on titanium substrates. This surface was shown to effectively degrade an organic model substance (rhodamine B) by generating reactive oxygen species (ROS) under UV illumination. However, it was shown that Ti-peroxy radical species remaining in the surface after the H2O2-oxidation process, rather than generation of ROS from a heterogeneous photocatalytic process, was responsible for the effect. This discovery was further exploited in a TiO2/H2O2/UV system, which demonstrated synergy effects in both rhodamine B degradation tests and in antibacterial assays. For the silver ion release strategy, a combinatorial materials science approach was employed. Binary Ag-Ti oxide gradients were co-deposited in a reactive (O2) environment using a custom built physical vapor deposition system, and evaluated for antibacterial properties. The approach enabled synthesis and composition-structure-property evaluation unlikely to have been achieved by traditional means, and the gradient coatings demonstrated antibacterial properties against both S. aureus and S. epidermidis according to silver ion release. The release was shown to depend more on structural features, such as surface area, crystallinity and oxidation state, than on composition. Ag-Ti oxide gradients were also evaluated under UV illumination, as Ag deposits on crystalline TiO2 can enhance photocatalytic properties. In this work, however, the TiO2 was amorphous and UV illumination caused a slight reduction in the antibacterial effect of silver ions. This was attributed to a UV-induced SOS response in the S. epidermidis bacteria. The results of this thesis demonstrate that both TiO2 photocatalysis, or UV induced activation of Ti-peroxy radical species, as well as incorporation of silver are viable antibacterial strategies for titanium biomaterials. However, their clinical applications are still pending risk-benefit analyses of potential adverse host tissue responses.

Antibacterial Strategies for Titanium Biomaterials

Titanium and titanium based alloys are widely used in dentistry and orthopedics to replace hard tissue and to mend broken bones. It has become a material of choice due to its low density, high strength, good biocompatibility and its capacity to integrate closely with the bone. Today, modern materials and surgical techniques can enable patients to live longer, and aid in maintaining or regaining mobility for a more fulfilling life. There are, however, instances where implants fail, and one of the primary causes for implant failure is infection. This thesis deals with two possible ways of reducing or eliminating implant associated infections; TiO2 photocatalysis, where a surface can become antibacterial upon irradiation with UV light; and incorporation of silver, where a subsequent release of silver metal ions result in an antibacterial effect. For the TiO2 photocatalysis strategy, a simple and cost effective chemical oxidation technique, using hydrogen peroxide (H2O2) and water, was used to create an active TiO2 surface on titanium substrates. This surface was shown to effectively degrade an organic model substance (rhodamine B) by generating reactive oxygen species (ROS) under UV illumination. However, it was shown that Ti-peroxy radical species remaining in the surface after the H2O2-oxidation process, rather than generation of ROS from a heterogeneous photocatalytic process, was responsible for the effect. This discovery was further exploited in a TiO2/H2O2/UV system, which demonstrated synergy effects in both rhodamine B degradation tests and in antibacterial assays. For the silver ion release strategy, a combinatorial materials science approach was employed. Binary Ag-Ti oxide gradients were co-deposited in a reactive (O2) environment using a custom built physical vapor deposition system, and evaluated for antibacterial properties. The approach enabled synthesis and composition-structure-property evaluation unlikely to have been achieved by traditional means, and the gradient coatings demonstrated antibacterial properties against both S. aureus and S. epidermidis according to silver ion release. The release was shown to depend more on structural features, such as surface area, crystallinity and oxidation state, than on composition. Ag-Ti oxide gradients were also evaluated under UV illumination, as Ag deposits on crystalline TiO2 can enhance photocatalytic properties. In this work, however, the TiO2 was amorphous and UV illumination caused a slight reduction in the antibacterial effect of silver ions. This was attributed to a UV-induced SOS response in the S. epidermidis bacteria. The results of this thesis demonstrate that both TiO2 photocatalysis, or UV induced activation of Ti-peroxy radical species, as well as incorporation of silver are viable antibacterial strategies for titanium biomaterials. However, their clinical applications are still pending risk-benefit analyses of potential adverse host tissue responses.

Antibacterial Strategies for Titanium Biomaterials

Titanium and titanium based alloys are widely used in dentistry and orthopedics to replace hard tissue and to mend broken bones. It has become a material of choice due to its low density, high strength, good biocompatibility and its capacity to integrate closely with the bone. Today, modern materials and surgical techniques can enable patients to live longer, and aid in maintaining or regaining mobility for a more fulfilling life. There are, however, instances where implants fail, and one of the primary causes for implant failure is infection. This thesis deals with two possible ways of reducing or eliminating implant associated infections; TiO2 photocatalysis, where a surface can become antibacterial upon irradiation with UV light; and incorporation of silver, where a subsequent release of silver metal ions result in an antibacterial effect. For the TiO2 photocatalysis strategy, a simple and cost effective chemical oxidation technique, using hydrogen peroxide (H2O2) and water, was used to create an active TiO2 surface on titanium substrates. This surface was shown to effectively degrade an organic model substance (rhodamine B) by generating reactive oxygen species (ROS) under UV illumination. However, it was shown that Ti-peroxy radical species remaining in the surface after the H2O2-oxidation process, rather than generation of ROS from a heterogeneous photocatalytic process, was responsible for the effect. This discovery was further exploited in a TiO2/H2O2/UV system, which demonstrated synergy effects in both rhodamine B degradation tests and in antibacterial assays. For the silver ion release strategy, a combinatorial materials science approach was employed. Binary Ag-Ti oxide gradients were co-deposited in a reactive (O2) environment using a custom built physical vapor deposition system, and evaluated for antibacterial properties. The approach enabled synthesis and composition-structure-property evaluation unlikely to have been achieved by traditional means, and the gradient coatings demonstrated antibacterial properties against both S. aureus and S. epidermidis according to silver ion release. The release was shown to depend more on structural features, such as surface area, crystallinity and oxidation state, than on composition. Ag-Ti oxide gradients were also evaluated under UV illumination, as Ag deposits on crystalline TiO2 can enhance photocatalytic properties. In this work, however, the TiO2 was amorphous and UV illumination caused a slight reduction in the antibacterial effect of silver ions. This was attributed to a UV-induced SOS response in the S. epidermidis bacteria. The results of this thesis demonstrate that both TiO2 photocatalysis, or UV induced activation of Ti-peroxy radical species, as well as incorporation of silver are viable antibacterial strategies for titanium biomaterials. However, their clinical applications are still pending risk-benefit analyses of potential adverse host tissue responses.

Mechanical properties and spreading characteristics of bone cement for spinal applications

Osteoporotic vertebral compression fractures can be successfully stabilized through vertebroplasty, a percutaneous injection of bone cement directly into the cancellous bone found in the vertebral body. Severe complications of this procedure can occur if bone cement leaks out of the targeted vertebra and enters the vascular system or spinal canal. Fractures of adjacent level vertebras may also be a consequence of the procedure since it leads to increased stiffness in the bone. In this work, a range of custom made polymethylmethacrylate (PMMA) bone cements for use in vertebroplasty were prepared in order to study the impact on handling characteristics, rheological and mechanical properties of three variables: the liquid to powder ratio, the concentration of crosslinker (ethylene glycol dimethacrylate) and the concentration of initiator (benzoyl peroxide). Bone cement containing the mean of these variables was used to study the spreading characteristics when injected at different viscosities in an artificial vertebral model made of rigid polyurethane foam. The spreading patterns were scanned using computed tomography and quantitatively described using the indicators circularity and mean cement spreading distance. Stiffness of the resulting foam/cement construct was also evaluated. In order to tailor PMMA bone cement for use in bone weakened by osteoporosis, an attempt was made to produce porous cement with lower Young’s modulus by adding various amounts of Castor oil. An evaluation of the particle release during curing of the porous cement was also made, as an excessive release of particles would limit its clinical use. Results show an increase in setting and dough times when increasing the liquid to powder ratio. A decrease in setting and dough times was noted when increasing the amounts of crosslinker and initiator. Peak polymerization temperature was found to increase with increased liquid to powder ratio, as well as when increasing the amounts of crosslinker and initiator. Addition of crosslinker was found to have the largest positive effect on cement strength. A higher liquid to powder ratio led to a decrease in Young’s modulus. Quantification of cement spreading showed a slight increase in circularity with increased viscosity, while no clear trend could be seen in measuring the mean cement spreading distance. A 10-fold increase in Young’s modulus was found when comparing PMMA filled samples of polyurethane foam with pure foam samples. Adding Castor oil to the cement led to significant lowering of both Young’s modulus and strength. The Young’s modulus was reduced from 1355 MPa for regular cement to on average 566 MPa when 30 vol% oil was added. The ultimate compressive strength decreased from 98 MPa for regular cement to on average 27 MPa with an addition of 30 vol% oil. No significant difference in particle release during curing was found when comparing regular cement with cement mixed with Castor oil. Careful consideration should to be taken when designing any new formulation of PMMA bone cement. Rheological and mechanical properties are key factors for a successful intervention and for the integrity of the treated and adjacent level vertebras. Rigid polyurethane foam was found to provide a realistic and simple model for simulating cement flow in cancellous bone, as well as a base for evaluating the mechanical effects of vertebroplasty. It was also found that generating pores in the cement by adding Castor oil is an effective way of lowering the modulus, making it more compliant with osteoporotic bone.Validerat; 20101217 (root

Vårdgaranti : Vem bär ansvaret för genomförandet? En samhällsanalys av regionens information till patienter

De flesta av oss kommer någon gång i livet att komma i kontakt med hälso- och sjukvården. Väntetiderna i vården är ett ämne som diskuteras i Sverige. Regeringen fattade ett beslut om att minska vårdköerna och år 2010 blev vårdgarantin lagstadgad på  nationell nivå. Lagarna säger att regionerna har ett ansvar att patienter ska få vård inom en viss tidsram samtidigt som patientens delaktighet i vården ska öka. I  vår undersökning kommer vi att analysera individens ansvar i genomförandet av vårdgarantin med tidsramen 90 dagar. Med hjälp av material som vi har begärt ut från Sveriges regioner kan vi med en textanalytisk metod undersöka ansvaret i vårdgarantin. Vi kan konstatera att resultatet skiljer sig åt mellan regionernas bifogade information. Det bör finnas en centraliserad information om vad vårdgarantin innebär för patienten i Sverige.