Oxidized cellulose
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BACKGROUND: Chronic lymphocytic leukemia (CLL) is a common adult leukemia characterized by the accumulation of neoplastic mature B cells in blood, bone marrow, lymph nodes, and spleen. The disease biology remains unresolved in many aspects, including the processes underlying the disease progression and relapses. However, studying CLL in vitro poses a considerable challenge due to its complexity and dependency on the microenvironment. Several approaches are utilized to overcome this issue, such as co-culture of CLL cells with other cell types, supplementing culture media with growth factors, or setting up a three-dimensional (3D) culture. Previous studies have shown that 3D cultures, compared to conventional ones, can lead to enhanced cell survival and altered gene expression. 3D cultures can also give valuable information while testing treatment response in vitro since they mimic the cell spatial organization more accurately than conventional culture. METHODS: In our study, we investigated the behavior of CLL cells in two types of material: (i) solid porous collagen scaffolds and (ii) gel composed of carboxymethyl cellulose and polyethylene glycol (CMC-PEG). We studied CLL cells' distribution, morphology, and viability in these materials by a transmitted-light and confocal microscopy. We also measured the metabolic activity of cultured cells. Additionally, the expression levels of MYC, VCAM1, MCL1, CXCR4, and CCL4 genes in CLL cells were studied by qPCR to observe whether our novel culture approaches lead to increased adhesion, lower apoptotic rates, or activation of cell signaling in relation to the enhanced contact with co-cultured cells. RESULTS: Both materials were biocompatible, translucent, and permeable, as assessed by metabolic assays, cell staining, and microscopy. While collagen scaffolds featured easy manipulation, washability, transferability, and biodegradability, CMC-PEG was advantageous for its easy preparation process and low variability in the number of accommodated cells. Both materials promoted cell-to-cell and cell-to-matrix interactions due to the scaffold structure and generation of cell aggregates. The metabolic activity of CLL cells cultured in CMC-PEG gel was similar to or higher than in conventional culture. Compared to the conventional culture, there was (i) a lower expression of VCAM1 in both materials, (ii) a higher expression of CCL4 in collagen scaffolds, and (iii) a lower expression of CXCR4 and MCL1 (transcript variant 2) in collagen scaffolds, while it was higher in a CMC-PEG gel. Hence, culture in the material can suppress the expression of a pro-apoptotic gene (MCL1 in collagen scaffolds) or replicate certain gene expression patterns attributed to CLL cells in lymphoid organs (low CXCR4, high CCL4 in collagen scaffolds) or blood (high CXCR4 in CMC-PEG).
- MeSH
- buněčné kultury metody MeSH
- chronická lymfatická leukemie * patologie metabolismus MeSH
- gely chemie MeSH
- kolagen * chemie farmakologie MeSH
- lidé MeSH
- polyethylenglykoly * chemie MeSH
- receptory CXCR4 metabolismus MeSH
- sodná sůl karboxymethylcelulosy * chemie farmakologie MeSH
- techniky 3D buněčné kultury metody MeSH
- tkáňové podpůrné struktury * chemie MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVE: This research aims to design and evaluate an enteric-coated hard capsule dosage form for targeted delivery of biological materials, such as FMT (fecal microbiota transplant) or live microbes, to the distal parts of the GIT. The capsules are designed to be internally protected against destruction by hydrophilic filling during passage through the digestive tract. METHODS: Hard gelatin capsules and DRcapsTMcapsules based on HPMC and gellan were used to encapsulate a hydrophilic body temperature-liquefying gelatin hydrogel with caffeine or insoluble iron oxide mixture. Different combinations of polymers were tested for the internal (ethylcellulose, Eudragit® E, and polyvinyl acetate) and external (Eudragit® S, Acryl-EZE®, and cellacefate) coating. The external protects against the acidic gastric environment, while the internal protects against the liquid hydrophilic filling during passage. Coated capsules were evaluated using standard disintegration and modified dissolution methods for delayed-release dosage forms. RESULTS: Combining suitable internal (ethylcellulose 1.0 %) and external (Eudragit® S 20.0 %) coating of DRcapsTM capsules with the wiping and immersion method achieved colonic release times. While most coated capsules met the pharmaceutical requirements for delayed release, one combination stood out. Colonic times were indicated by the dissolution of soluble caffeine (during 120-720 min) measured by the dissolution method, and capsule rupture was indicated by the release of insoluble iron oxide (after 480 min) measured by the disintegration method. This promising result demonstrates the composition's suitability and potential to protect the content until it's released, inspiring hope for the future of colon-targeted delivery systems and its potential for the pharmaceutical and biomedical fields. CONCLUSION: Innovative and easy capsule coatings offer significant potential for targeted drugs, especially FMT water suspension, to the GIT, preferably the colon. The administration method is robust and not considerably affected by the quantity of internal or external coatings. It can be performed in regular laboratories without specialized individual and personalized treatment equipment, making it a practical and feasible method for drug delivery.
- MeSH
- bakteriální polysacharidy chemie MeSH
- biokompatibilní materiály chemie MeSH
- celulosa * chemie analogy a deriváty MeSH
- deriváty hypromelózy chemie MeSH
- hydrofobní a hydrofilní interakce * MeSH
- hydrogely chemie MeSH
- kofein chemie aplikace a dávkování MeSH
- kolon * metabolismus MeSH
- kyseliny polymethakrylové chemie MeSH
- lékové transportní systémy * metody MeSH
- léky s prodlouženým účinkem chemie MeSH
- polymery chemie MeSH
- polyvinyly chemie MeSH
- tobolky * MeSH
- uvolňování léčiv * MeSH
- želatina * chemie MeSH
- železité sloučeniny chemie aplikace a dávkování MeSH
- Publikační typ
- časopisecké články MeSH
Several studies have reported on application of cellulose particles for stabilizing Pickering emulsions (PE). Here we employ an original approach that involves using these particles as a part of advanced composite colloids made of conducting polymer polyaniline (PANI) and cellulose nanocrystals (CNC) or nanofibrils (CNF). PANI/cellulose particles were prepared using oxidative polymerization of aniline in situ in the presence of CNC or CNF. The type and amount of celluloses (CNC vs CNF) and concentration of precursors (aniline monomer and oxidant) used in the reaction determined properties of the colloidal particles, such as size, morphology and content of PANI. The particles demonstrated intriguing biological characteristics, including no cytotoxicity, antibacterial activity against Staphylococcus aureus and Escherichia coli, antioxidant activity and related immunomodulatory activity. For the first time, such composites were used to successfully stabilize oil-in-water PE with undecane or capric/caprylic triglyceride oils. The properties of the emulsions were determined by the PANI/cellulose particles and oil used. The key finding of the study is the demonstrated ability of PANI/cellulose particles to stabilize PE, as well as the excellent antioxidant activity and ROS scavenging action originating from PANI presence, indicating potential of such systems for use in biomedicine, particularly for wound healing.
PURPOSE: Various forms of local haemostats are increasingly used routinely in surgical procedures. Our work is the first comparison of the efficacy and safety of non-regenerated and regenerated oxidized cellulose based fibrous haemostats. METHODS: The haemostatic efficacy and safety of fibrous haemostats based on ONRC and ORC were compared in a randomized multicenter study. The primary endpoint was successful haemostasis within 3 minutes of application and no need for surgical revision within 12 hours after the procedure for recurrent bleeding. RESULTS: There was a significant difference in the rate of successful haemostasis in 3 minutes that was achieved in 82% and 55% in the ONRC and ORC groups, respectively (confidence interval 99%; p = 0.009). Mean time to haemostasis was 133.9 ± 53.95 seconds and 178.0 ± 82.33 seconds, in the ONRC, and ORC group, respectively (p = 0.002). Revision surgery for re-bleeding was necessary in 0 (0%), and 1 (2%) of patients in the ONRC, and ORC group, respectively. No adverse events were reported. CONCLUSION: Fibrous haemostat based on ONRC was non-inferior compared to fibrous haemostat based on ORC when used in accordance with its intended purpose, and was safe and efficient.
- MeSH
- celulosa oxidovaná * terapeutické užití MeSH
- hemostatika * terapeutické užití MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- randomizované kontrolované studie MeSH
Pharmaceutical nanocrystals represent a promising new formulation that combines the benefits of bulk crystalline materials and colloidal nanoparticles. To be applied in vivo, nanocrystals must meet several criteria, namely colloidal stability in physiological media, non-toxicity to healthy cells, avoidance of macrophage clearance, and bioactivity in the target tissue. In the present work, curcumin, a naturally occurring poorly water-soluble molecule with a broad spectrum of bioactivity has been considered a candidate substance for preparing pharmaceutical nanocrystals. Curcumin nanocrystals in the size range of 40-90 nm were prepared by wet milling using the following combination of steric and ionic stabilizers: Tween 80, sodium dodecyl sulfate, Poloxamer 188, hydroxypropyl methylcellulose, phospholipids (with and without polyethylene glycol), and their combination. Nanocrystals stabilized by a combination of phospholipids enriched with polyethylene glycol proved to be the most successful in all evaluated criteria; they were colloidally stable in all media, exhibited low macrophage clearance, and proved non-toxic to healthy cells. This curcumin nanoformulation also exhibited outstanding anticancer potential comparable to commercially used cytostatics (IC50 = 73 μM; 24 h, HT-29 colorectal carcinoma cell line) which represents an improvement of several orders of magnitude when compared to previously studied curcumin formulations. This work shows that the preparation of phospholipid-stabilized nanocrystals allows for the conversion of poorly soluble compounds into a highly effective "solution-like" drug delivery system at pharmaceutically relevant drug concentrations.
- MeSH
- deriváty hypromelózy MeSH
- dodecylsíran sodný chemie MeSH
- fosfolipidy MeSH
- kurkumin * chemie farmakologie MeSH
- léčivé přípravky MeSH
- makrofágy MeSH
- nanočástice * chemie MeSH
- poloxamer chemie MeSH
- polyethylenglykoly chemie MeSH
- polysorbáty MeSH
- rozpustnost MeSH
- velikost částic MeSH
- voda MeSH
- Publikační typ
- časopisecké články MeSH
Study provides an in-depth analysis of the structure-function relationship of polysaccharide anticancer drug carriers and points out benefits and potential drawbacks of differences in polysaccharide glycosidic bonding, branching and drug binding mode of the carriers. Cellulose, dextrin, dextran and hyaluronic acid have been regioselectively oxidized to respective dicarboxylated derivatives, allowing them to directly conjugate cisplatin, while preserving their major structural features intact. The structure of source polysaccharide has crucial impact on conjugation effectiveness, carrier capacity, drug release rates, in vitro cytotoxicity and cellular uptake. For example, while branched structure of dextrin-based carrier partially counter the undesirable initial burst release, it also attenuates the cellular uptake and the cytotoxicity of carried drug. Linear polysaccharides containing β-(1→4) glycosidic bonds and oxidized at C2 and C3 (cellulose and hyaluronate) have the best overall combination of structural features for improved drug delivery applications including potentiation of the cisplatin efficacy towards malignances.
- MeSH
- buňky NIH 3T3 MeSH
- celulosa chemie MeSH
- cisplatina aplikace a dávkování MeSH
- dextrany chemie MeSH
- dextriny chemie MeSH
- glykosidy chemie MeSH
- inhibiční koncentrace 50 MeSH
- kyselina hyaluronová chemie MeSH
- kyslík chemie MeSH
- lékové transportní systémy * MeSH
- lidé MeSH
- MFC-7 buňky MeSH
- myši MeSH
- nosiče léků * MeSH
- oxidace-redukce MeSH
- platina chemie MeSH
- polysacharidy chemie MeSH
- protinádorové látky aplikace a dávkování MeSH
- techniky in vitro MeSH
- uvolňování léčiv MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The Canary Islands, an archipelago east of Morocco's Atlantic coast, present steep altitudinal gradients covering various climatic zones from hot deserts to subalpine Mediterranean, passing through fog-influenced cloud forests. Unlike the majority of the Canarian flora, Pinus canariensis C. Sm. ex DC. in Buch grow along most of these gradients, allowing the study of plant functioning in contrasting ecosystems. Here we assess the water sources (precipitation, fog) of P. canariensis and its physiological behavior in its different natural environments. We analyzed carbon and oxygen isotope ratios of water and organics from atmosphere, soil and different plant organs and tissues (including 10-year annual time series of tree-ring cellulose) of six sites from 480 to 1990 m above sea level on the Canary Island La Palma. We found a decreasing δ18O trend in source water that was overridden by an increasing δ18O trend in needle water, leaf assimilates and tree-ring cellulose with increasing altitude, suggesting site-specific tree physiological responses to relative humidity. Fog-influenced and fog-free sites showed similar δ13C values, suggesting photosynthetic activity to be limited by stomatal closure and irradiance at certain periods. In addition, we observed an 18O-depletion (fog-free and timberline sites) and 13C-depletion (fog-influenced and fog-free sites) in latewood compared with earlywood caused by seasonal differences in: (i) water uptake (i.e., deeper ground water during summer drought, fog water frequency and interception) and (ii) meteorological conditions (stem radial growth and latewood δ18O correlated with winter precipitation). In addition, we found evidence for foliar water uptake and strong isotopic gradients along the pine needle axis in water and assimilates. These gradients are likely the reason for an unexpected underestimation of pine needle water δ18O when applying standard leaf water δ18O models. Our results indicate that soil water availability and air humidity conditions are the main drivers of the physiological behavior of pine along the Canary Island's altitudinal gradients.
- MeSH
- borovice * MeSH
- ekosystém MeSH
- izotopy kyslíku analýza MeSH
- izotopy uhlíku analýza MeSH
- stromy MeSH
- voda * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Španělsko MeSH
Natural biopolymers, polymeric organic molecules produced by living organisms and/or renewable resources, are considered greener, sustainable, and eco-friendly materials. Natural polysaccharides comprising cellulose, chitin/chitosan, starch, gum, alginate, and pectin are sustainable materials owing to their outstanding structural features, abundant availability, and nontoxicity, ease of modification, biocompatibility, and promissing potentials. Plentiful polysaccharides have been utilized for making assorted (nano)catalysts in recent years; fabrication of polysaccharides-supported metal/metal oxide (nano)materials is one of the effective strategies in nanotechnology. Water is one of the world's foremost environmental stress concerns. Nanomaterial-adorned polysaccharides-based entities have functioned as novel and more efficient (nano)catalysts or sorbents in eliminating an array of aqueous pollutants and contaminants, including ionic metals and organic/inorganic pollutants from wastewater. This review encompasses recent advancements, trends and challenges for natural biopolymers assembled from renewable resources for exploitation in the production of starch, cellulose, pectin, gum, alginate, chitin and chitosan-derived (nano)materials.
- MeSH
- adsorpce MeSH
- algináty MeSH
- biopolymery * MeSH
- celulosa MeSH
- chemické látky znečišťující vodu chemie izolace a purifikace MeSH
- chitin MeSH
- chitosan MeSH
- čištění vody metody MeSH
- katalýza MeSH
- nanostruktury * chemie MeSH
- nanotechnologie MeSH
- ochrana vodních zdrojů MeSH
- odpadní voda chemie MeSH
- pektiny MeSH
- škrob MeSH
- technologie zelené chemie MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Magnetic polymer nanocomposites are inherently multifunctional and harbor assorted physiochemical actions for applications thereof as novel drug nanocarriers. Herein, Fe3O4-nanoparticles were supported on rice straw cellulose for 5-fluorouracil carrier abbreviated as MC/5-FU for potential colorectal cancer treatments. Several analyses indicated the multifunctional properties of MC/5-FU bionanocomposites. Transmission and scanning electron microscopy study demonstrated that Fe3O4 nanofillers covered the cellulose matrix. The drug release from MC/5-FU was evaluated under various pH and temperature conditions, showing the maximum release at pH 7.4 and 44.2 °C. In in vitro anticancer assay, MC/5-FU exhibited enhanced selectivity and anticancer actions against 2D monolayer and 3D tumour spheroid models colorectal cancer cells. The anticancer effects of MC/5-FU with magnetic targeting and heat induction were also examined. This easily synthesized MC/5-FU indicated the potential in application as a low-cost drug formulation for colorectal cancer treatments.
- MeSH
- buňky HT-29 MeSH
- celulosa chemie MeSH
- fluoruracil chemie farmakologie MeSH
- HCT116 buňky MeSH
- kolorektální nádory farmakoterapie metabolismus MeSH
- lékové transportní systémy metody MeSH
- lidé MeSH
- magnetické jevy MeSH
- magnetické nanočástice oxidů železa chemie MeSH
- mikroskopie elektronová rastrovací metody MeSH
- nanokompozity chemie MeSH
- nosiče léků chemie MeSH
- polymery chemie MeSH
- protinádorové látky farmakologie MeSH
- uvolňování léčiv MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Many growth factors have been studied as additives accelerating lumbar fusion rates in different animal models. However, their low hydrolytic and thermal stability both in vitro and in vivo limits their workability and use. In the proposed work, a stabilized vasculogenic and prohealing fibroblast growth factor-2 (FGF2-STAB®) exhibiting a functional half-life in vitro at 37 °C more than 20 days was applied for lumbar fusion in combination with a bioresorbable scaffold on porcine models. An experimental animal study was designed to investigate the intervertebral fusion efficiency and safety of a bioresorbable ceramic/biopolymer hybrid implant enriched with FGF2-STAB® in comparison with a tricortical bone autograft used as a gold standard. Twenty-four experimental pigs underwent L2/3 discectomy with implantation of either the tricortical iliac crest bone autograft or the bioresorbable hybrid implant (BHI) followed by lateral intervertebral fixation. The quality of spinal fusion was assessed by micro-computed tomography (micro-CT), biomechanical testing, and histological examination at both 8 and 16 weeks after the surgery. While 8 weeks after implantation, micro-CT analysis demonstrated similar fusion quality in both groups, in contrast, spines with BHI involving inorganic hydroxyapatite and tricalcium phosphate along with organic collagen, oxidized cellulose, and FGF2- STAB® showed a significant increase in a fusion quality in comparison to the autograft group 16 weeks post-surgery (p = 0.023). Biomechanical testing revealed significantly higher stiffness of spines treated with the bioresorbable hybrid implant group compared to the autograft group (p < 0.05). Whilst histomorphological evaluation showed significant progression of new bone formation in the BHI group besides non-union and fibrocartilage tissue formed in the autograft group. Significant osteoinductive effects of BHI based on bioceramics, collagen, oxidized cellulose, and FGF2-STAB® could improve outcomes in spinal fusion surgery and bone tissue regeneration.
- Publikační typ
- časopisecké články MeSH