shape memory polymers
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Lékové formy s elektronickým prvkem je možné zařadit mezi jedny z nejmodernějších a nejinovativnějších lékových systémů posledních několika dekád. Inkorporace elektronického/digitálního prvku nabízí řadu výhod, jako např. možnost přesného načasování uvolnění léčivé látky v požadované lokaci gastrointestinálního traktu, sběr biometrických dat, či nezpochybnitelný průkaz adherence pacienta k terapii. V současné době je možné pozorovat vývoj oboru do dvou hlavních směrů. Tím prvním je využití těchto systémů ve spojení s řízeným uvolňováním při absorpčních a obecně farmakokinetických studiích nových látek. Druhým směrem je pak digitální monitoring adherence k léčbě. Tento stručný přehled pojednává krátce o historii problematiky, přináší informace o obou zmíněných odvětvích a zmiňuje zásadní zástupce obou skupin a jejich využití.
Delivery systems with an electronic element can be classified as one of the last few decades' most modern and innovative pharmaceutical systems. Incorporating an electronic/digital element offers several advantages, such as the possibility of the precise timing of the drug released in the desired location of the gastrointestinal tract, collection of biometric data, or indisputable proof of the patient's adherence to therapy. Currently, it is possible to observe the development of the field in two main directions. The first one is using these systems in conjunction with the controlled release principle in absorption and general pharmacokinetic studies of new substances. The second direction is digital monitoring of therapy adherence. This brief overview briefly mentions the field's history, brings information about the two main branches, and states the essential systems of both branches and their use.
Shape memory alloys (SMA) are materials with specific electric, mechanic and thermal qualities originating in their microscopic structure and as such are used to design so-called Smart structures. In biomedicine, they are used mostly for their shape memory properties during intravasal surgery. The commonly used SMA material for biomedical purposes is Nitinol, a nickel-titanium alloy that exhibits, especially when annealed, among other properties also superelasticity and high resistivity with strain changes. This makes it suitable for usage in strain gauge sensors. In this work, NiTi annealed wires were used to create a strain gauge sensor, which exploits their unique properties. The properties of these sensors were then described using a climatic chamber, stretching device and a set of weights. Those properties were then compared to similar sensors, that are using different principles. The development, that followed, used these sensors in particular biomedical applications.
- MeSH
- automatizované zpracování dat metody přístrojové vybavení MeSH
- biomedicínské technologie MeSH
- biomedicínský výzkum MeSH
- chytré materiály analýza škodlivé účinky terapeutické užití MeSH
- elektrická impedance MeSH
- kvantitativní vztahy mezi strukturou a aktivitou MeSH
- manometrie metody přístrojové vybavení MeSH
- nikl škodlivé účinky terapeutické užití MeSH
- slitiny s tvarovou pamětí * chemie klasifikace škodlivé účinky MeSH
- titan škodlivé účinky terapeutické užití MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Here we present a new effective antibacterial material suitable for a coating, e.g., surface treatment of textiles, which is also time and financially undemanding. The most important role is played by hydrophobic carbon quantum dots, as a new type of photosensitizer, produced by carbonization of different carbon precursors, which are incorporated by swelling from solution into various polymer matrices in the form of thin films, in particular polyurethanes, which are currently commercially used for industrial surface treatment of textiles. The role of hydrophobic carbon quantum dots is to work as photosensitizers upon irradiation and produce reactive oxygen species, namely singlet oxygen, which is already known as the most effective radical for elimination different kinds of bacteria on the surface or in close proximity to such modified material. Therefore, we have mainly studied the effect of hydrophobic carbon quantum dots on Staphylococcus aureus and the cytotoxicity tests, which are essential for the safe handling of such material. Also, the production of singlet oxygen by several methods (electron paramagnetic spectroscopy, time-resolved near-infrared spectroscopy), surface structures (atomic force microscopy and contact angle measurement), and the effect of radiation on polymer matrices were studied. The prepared material is easily modulated by end-user requirements.
- MeSH
- antibakteriální látky chemie MeSH
- biofilmy MeSH
- biokompatibilní potahované materiály chemie MeSH
- chytré materiály chemie MeSH
- fotosenzibilizující látky chemie MeSH
- hydrofobní a hydrofilní interakce MeSH
- kvantové tečky chemie MeSH
- myši MeSH
- povrchové vlastnosti MeSH
- reaktivní formy kyslíku metabolismus MeSH
- singletový kyslík chemie MeSH
- Staphylococcus aureus MeSH
- uhlík chemie MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Biodegradable stents are promising treatments for many diseases, e.g., coronary artery disease, urethral diseases, tracheal diseases, and esophageal strictures. The mechanical properties of biodegradable stent materials play a key role in the safety and efficacy of treatment. In particular, insufficient creep resistance of the stent material could result in premature stent collapse or narrowing. Commercially available biodegradable self-expandable SX-ELLA stents made of polydioxanone monofilament were tested. A new, simple, and affordable method to measure the shear modulus of tiny viscoelastic wires is presented. The important mechanical parameters of the polydioxanone filament were obtained: the median Young's modulus was [Formula: see text] = 958 (922, 974) MPa and the shear modulus was [Formula: see text] = 357 (185, 387) MPa, resulting in a Poisson's ratio of ν = 0.34. The SX-ELLA stents exhibited significant force relaxation due to the stress relaxation of the polydioxanone monofilament, approximately 19% and 36% 10 min and 48 h after stent application, respectively. However, these results were expected, and the manufacturer and implanting clinician should be aware of the known behavior of these biodegradable materials. If possible, a biodegradable stent should be designed considering therapeutic force rather than initial force. Additionally, new and more advanced biodegradable shape-memory polymers should be considered for future study and use.
The design of smart surfaces with externally triggerable water/oil wettability and adhesion represents one of the most up-to-date challenges in the field of material science. In this work, the intelligent surface with electrically triggerable wettability and water/oil adhesion is presented. As a basic material background exhibiting electric field (EF) sensitivity, the piezo-responsive polymethylmethacrylate/polyvinylidenefluoride polymer fibers were used. To expand the available range of water/oil contact angles (CAs) and adhesion, the fibers were grafted with hydrophilic or hydrophobic functional groups using diazonium chemistry. The fiber functionality was evaluated using the static CA and wettability hysteresis measurements (increasing/decreasing drop volume and tilting angles), drops adhesion/repellence and graphite self-cleaning test performed with and without the application of EF. It was found that the proposed method enables tuning the surface wettability in the superhydrophobic/superoleophobic-hydrophilic/oleophilic range and changing of surface properties from low adhesive to high adhesive for water and oil. More convincing results were achieved in the case of fiber surface modification by ADT-C8F17, which may result from a rearrangement of the grated -C6H4C8F17 functional group under the application of EF triggering. Moreover, the triggering which can be performed in the extremely fast way (the surface responds to the EF switching on/off in seconds) was found to be fully reversible. Finally, the additional tests indicate the satisfactory stability of created fiber-based coating against the mechanical treatment.
- MeSH
- chytré materiály MeSH
- komfort pacienta MeSH
- kontaktní čočky * MeSH
- lidé MeSH
- oči MeSH
- oční víčka MeSH
- technologie MeSH
- Check Tag
- lidé MeSH
... -8 The interaction of antigens with antigen receptors induces lymphocytes to acquire effector and memory ... ... cells. 471 -- Summary. 472 -- Immunological memory. 473 -- 11-17 Immunological memory is long lived ... ... after infection or vaccination. 473 -- 11-18 Memory ? ... ... cells. 475 -- 11-19 Memory ? ... ... T cells are heterogeneous and include central memory, effector memory, and tissue-resident subsets. 480 ...
9th edition xx, 904 stran : ilustrace, tabulky ; 28 cm
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- alergologie a imunologie
- biologie
- fyziologie
- NLK Publikační typ
- kolektivní monografie
... 67 -- There Are Many Other Activated Carrier Molecules in Cells 68 -- The Synthesis of Biological Polymers ... ... AND STRUCTURE OF PROTEINS 109 -- The Shape of a Protein Is Specified by Its Amino Acid Sequence 109 ... ... Globular Proteins Form Long Helical Filaments 123 -- Many Protein Molecules Have Elongated, Fibrous Shapes ... ... and Polymer-destabilizing Chemicals Actin-Binding Proteins Influence Filament Dynamics and Organization ... ... and Polymer-destabilizing Drugs A Protein Complex Containing y-Tubulin Nucleates Microtubules Microtubules ...
Sixth edition xxxiv, 1430 stran v různém stránkování : ilustrace (převážně barevné) ; 29 cm
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- molekulární biologie, molekulární medicína
- NLK Publikační typ
- učebnice vysokých škol
