Multilayer
Dotaz
Zobrazit nápovědu
This study aims to design an optimal polyelectrolyte multilayer film of poly-l-lysine (PLL) and hyaluronic acid (HA) as an anti-inflammatory cytokine release system in order to decrease the implant failure due to any immune reactions. The chemical modification of the HA with aldehyde moieties allows self-cross-linking of the film and an improvement in the mechanical properties of the film. The cross-linking of the film and the release of immunomodulatory cytokine (IL-4) stimulate the differentiation of primary human monocytes seeded on the films into pro-healing macrophages phenotype. This induces the production of anti-inflammatory cytokines (IL1-RA and CCL18) and the decrease of pro-inflammatory cytokines secreted (IL-12, TNF-α, and IL-1β). Moreover, we demonstrate that cross-linking PLL/HA film using HA-aldehyde is already effective by itself to limit inflammatory processes. Finally, this functionalized self-cross-linked PLL/HA-aldehyde films constitutes an innovative and efficient candidate for immunomodulation of any kind of implants of various architecture and properties.
- MeSH
- buněčná adheze účinky léků MeSH
- buněčná diferenciace účinky léků MeSH
- cytokiny aplikace a dávkování chemie MeSH
- imunomodulace účinky léků MeSH
- kultivované buňky MeSH
- kyselina hyaluronová chemie MeSH
- lidé MeSH
- makrofágy cytologie účinky léků metabolismus MeSH
- monocyty cytologie účinky léků metabolismus MeSH
- polyelektrolyty chemie MeSH
- povrchové vlastnosti MeSH
- reagencia zkříženě vázaná chemie MeSH
- zánět farmakoterapie imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The scarcity of high-quality annotations in many application scenarios has recently led to an increasing interest in devising learning techniques that combine unlabeled data with labeled data in a network. In this work, we focus on the label propagation problem in multilayer networks. Our approach is inspired by the heat diffusion model, which shows usefulness in machine learning problems such as classification and dimensionality reduction. We propose a novel boundary-based heat diffusion algorithm that guarantees a closed-form solution with an efficient implementation. We experimentally validated our method on synthetic networks and five real-world multilayer network datasets representing scientific coauthorship, spreading drug adoption among physicians, two bibliographic networks, and a movie network. The results demonstrate the benefits of the proposed algorithm, where our boundary-based heat diffusion dominates the performance of the state-of-the-art methods.
- MeSH
- algoritmy MeSH
- řízené strojové učení * MeSH
- strojové učení MeSH
- vysoká teplota * MeSH
- Publikační typ
- časopisecké články MeSH
Úvod: Najnovšie poznatky dokázali histopatologickú, genetickú, aj klinickú uniformitu v prípade tumorov označovaných ako embryonálne tumory s mnohovrstvovými rozetami, kam patrí meduloepitelióm, ependymoblastóm a embryonálny tumor s abundatným neuropilom a pravými rozetami. Spoločným znakom je pozitivita LIN28A a amplifikácia lokusu 19q13.42, ktorý zahrňuje C19MC klaster obsahujúci gény pre mikroRNA. V patogenéze ochorenia hrá významnú úlohu dysregulácia epigenetických modifikátorov. Tieto tumory sú pozorované u najmenších detí (medián veku pod 3 roky), miera celkového prežívania je menej ako 5–10 %. Kazuistika: Temer trojročný chlapec s histologicky dokázaným tumorom mozgového kmeňa: meduloepiteliom WHO grade IV. Prišiel s príznakmi dyzartrie, bulbárneho syndrómu, centrálnej lézie n.V a kvadruparézy s pravostrannou prevahou. Od marca do konca mája 2014 dostal tri cykly indukčnej chemoterapie (protokol COG ACNS0334). Dosiahlo sa iba prechodné zlepšenie klinického stavu. V prestávke liečby sa objavili príznaky intrakraniálnej hypertenzie s potrebou zavedenia ventrikulo‑peritoneálnej drenáže, vznikla porucha vedomia v zmysle soporu. Z vitálnej indikácie dostal rádioterapiu. Po podaní dvoch frakcií – boost na ložisko tumoru – pacient upadol do kómy, na MRI sa demarkovala metastáza v mieche v úrovni C3. CT vyšetrením sa zistilo obojstranné ložiskové postihnutie v pľúcnom parenchýme, podľa popisu rádiológa mali charakter metastáz (histologizácia ložísk nerealizovaná). Pacient zomrel v auguste 2014, šesť mesiacov od prvých príznakov ochorenia. Záver: Referovaním tejto kazuistiky sme dokumentovali prvý na Slovensku zaznamenaný prípad tumoru zo skupiny embryonálnych tumorov s mnohovrstvovými rozetami. V súčasnosti neexistuje účinná liečba týchto tumorov. Prísľubom do budúcna je výskum molekúl zacielených na epigenetické modifikátory. Klíčové slová: meduloepitelióm – ependymoblastóm – embryonálne tumory s mnohovrstvovými rozetami – mikroRNA – 19q13.42 – C19MC – LIN28
Introduction: The most recent findings show a histopathological, genetic and clinical uniformity in cases of tumors called embryonal tumors with multilayer rosettes. This group is composed of medulloepithelioma, ependymoblastoma and embryonal tumor with abundant neuropil and true rosettes. Amplification of locus 19q13.42, which includes C19MC cluster containing genes for microRNA, and also LIN28A positivity are present in all three entities. Dysregulation of epigenetic modifiers is very important in pathogenesis of the disease. These tumors manifest in little children (median less than 3 years of age); overall survival is 5–10%. Case report: Almost three year-old boy diagnosed with brainstem tumor: meduloepithelioma, WHO grade IV confirmed by histological investigation. He presented with dysarthria, bulbar syndrome, central lesion of the facial nerve, quadriparesis with right-side dominancy. He received three induction cycles of chemotherapy from March to May 2014 (according to protocol COG ACNS0334). Only partial improvement of his clinical state was reached. Signs of an intracranial hypertension appeared resulting in VP shunt insertion; impairment of consciousness developed after the induction cycles and before any other treatment could be initiated. He underwent radiotherapy due to vital indication. After application of two fractions (boost in the center of the tumor), the patient became quickly comatose. Spinal cord metastasis was demarked by MRI scan (in the level of 3rd cervical vertebra). A bilateral infiltration in pulmonary parenchyma, according to a radiologist metastasis-wise, was detected by CT scan (histologisation of infiltration was not implemented). The patient died in August 2014 – six months after manifestation of first symptoms. Conclusion: We reported our first documented case of a patient with tumor from embryonal tumors with multilayer rosettes group in Slovakia. Nowadays, there is no effective treatment of these tumors. Research of molecules targeting to epigenetic modifiers would be one of the possible promises for future therapy. Key words: medulloepithelioma – ependymoblastoma – embryonal tumors with multilayer rosettes – microRNA – 19q13.42 – C19MC – LIN28 The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers. Submitted: 26. 5. 2015 Accepted: 24. 6. 2015
- MeSH
- celková dávka radioterapie MeSH
- cytostatické látky terapeutické užití MeSH
- fatální výsledek * MeSH
- germinální a embryonální nádory * farmakoterapie genetika patofyziologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- metastázy nádorů MeSH
- metylace DNA genetika MeSH
- nádory mozku farmakoterapie patofyziologie MeSH
- předškolní dítě MeSH
- příznaky a symptomy MeSH
- prognóza MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- Publikační typ
- kazuistiky MeSH
Polyelectrolyte layer-by-layer (LbL) films that disintegrate under physiological conditions are intensively studied as coatings to enable the release of bioactive components. Herein, we report on the interactions and pH-stability of LbL films composed of chitosan (CH) or N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (CMCH) and tannic acid (TA), employed to guarantee the film disintegration. The self-assembly of TA with CH and CMCH at pH 5 and with CMCH at pH 7.4 were proven by turbidimetric, surface plasmon resonance and UV-Vis analyses. The LbL films exhibited pH-dependent properties; CMCH/TA films prepared at pH 7.4 showed exponential growth as well as a higher layer thickness and surface roughness, whereas films prepared at pH 5 grew linearly and were smoother. The film stability varied with the pH used for film assembly; CH/TA films assembled at pH 5 were unstable at pH 8.5, whereas CMCH/TA films assembled at pH 7.4 disintegrated at pH 4. All films exhibited a similar disassembly at pH 7.4. The coatings reduced the adhesion of E. coli and S. aureus by approximately 80%. CMCH-terminated CMCH/TA films were more resistant to bacterial adhesion, whereas CH-terminated CH/TA films demonstrated stronger killing activity. The prepared pH-triggered decomposable LbL films could be used as degradable coatings that allow the release of therapeutics for biomedical applications and also prevent bacterial adhesion.
- MeSH
- antibakteriální látky farmakologie MeSH
- biokompatibilní materiály chemie farmakologie MeSH
- chitosan chemie MeSH
- Escherichia coli účinky léků MeSH
- film jako téma MeSH
- koncentrace vodíkových iontů MeSH
- Staphylococcus aureus účinky léků MeSH
- taniny chemie MeSH
- Publikační typ
- časopisecké články MeSH
Understanding the behavior of single proteins at the polyelectrolyte multilayer film/solution interface is of prime importance for the designing of bio-functionalized surface coatings. In the present paper, we study the adsorption of the model proteins, albumin and lysozyme, as well as basic fibroblast growth factor (FGF-2) on a polysaccharide multilayer film composed of quaternized chitosan and heparin. Several analytical methods were used to describe the formation of the polysaccharide film and its interactions with the proteins. Both albumin and lysozyme adsorbed on quaternized chitosan/heparin films, however this process strongly depended on the terminating polysaccharide. Protein adsorption was driven mainly by electrostatic interactions between protein and the terminal layer of the film. The effective binding of FGF-2 by the heparin-terminated film suggested that other interactions could also contribute to the adsorption process. We believe that this FGF-2-presenting polysaccharide film may serve as a biofunctional surface coating for biologically-related applications.
PURPOSE: The tear film lipid layer (TFLL) covers the tear film, stabilizing it and providing a protective barrier against the environment. The TFLL is divided into polar and non-polar sublayers, but the interplay between lipid classes in these sublayers and the structure-function relationship of the TFLL remains poorly characterized. This study aims to provide insight into TFLL function by elucidating the interactions between polar and non-polar TFLL lipids at the molecular level. METHODS: Mixed films of polar O-acyl-ω-hydroxy fatty acids (OAHFA) or phospholipids and non-polar cholesteryl esters (CE) were used as a model of the TFLL. The organization of the films was studied by using a combination of Brewster angle and fluorescence microscopy in a Langmuir trough system. In addition, the evaporation resistance of the lipid films was evaluated. RESULTS: Phospholipids and OAHFAs induced the formation of a stable multilamellar CE film. The formation of this film was driven by the interdigitation of acyl chains between the monolayer of polar lipids and the CE multilayer lamellae. Surprisingly, the multilayer structure was destabilized by both low and high concentrations of polar lipids. In addition, the CE multilayer was no more effective in resisting the evaporation of water than a polar lipid monolayer. CONCLUSIONS: Formation of multilamellar films by major tear film lipids suggest that the TFLL may have a similar structure. Moreover, in contrast to the current understanding, polar TFLL lipids may not mainly act by stabilizing the non-polar TFLL sublayer, but through a direct evaporation resistant effect.
- MeSH
- estery cholesterolu MeSH
- lipidy MeSH
- mastné kyseliny MeSH
- slzy * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
