scholarly journals Silicone-covered biodegradable magnesium-stent insertion in the esophagus: a comparison with plastic stents

2016 ◽  
Vol 10 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Yue-Qi Zhu ◽  
Kai Yang ◽  
Laura Edmonds ◽  
Li-Ming Wei ◽  
Reila Zheng ◽  
...  
Keyword(s):  
Radial Force ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Esophageal Injury ◽  
Plastic Stents ◽  
Esophageal Wall ◽  
Control Group ◽  
Stent Insertion ◽  
Biodegradable Magnesium

Background: We determined the feasibility of, and tissue response to silicone-covered biodegradable magnesium- and plastic-stent insertion into the esophagus in rabbits. Methods: The mechanical compression–recovery characteristics and degradation behaviors of the magnesium stent were investigated in vitro. A total of 45 rabbits were randomly divided into a magnesium- ( n = 15) and a plastic- ( n = 15) stent group, and underwent stent insertion into the lower third of the esophagus under fluoroscopic guidance; a control group ( n = 15) did not undergo the intervention. Esophagography was performed at 1, 2, and 4 weeks. Five rabbits in each group were euthanized at each time point for histological examination. Results: Silicone-covered magnesium stents showed similar radial force to plastic stents ( p > 0.05). The magnesium stents degraded rapidly in an acidic solution, but 90.2% ± 3.1% of the residual mass was maintained after a 2-week degradation in a solution with a pH of 4.0. All stent insertions were well tolerated. Magnesium stents migrated in six rabbits (one at 1 week, one at 2 weeks and four at 4 weeks), and plastic stents migrated in three rabbits (one at 2 weeks and two at 4 weeks; p > 0.05). Esophageal wall remodeling (thinner epithelial and smooth muscle layers) was similar in both stented groups ( p > 0.05), and the esophagus wall was found to be significantly thinner in the stented groups than in the control group ( p < 0.05). Esophageal injury and collagen deposition following stent insertion were similar and did not differ from the control group ( p > 0.05). Conclusions: Esophageal silicone-covered magnesium stents provided reliable support for at least 2 weeks, with acceptable migration rates and without causing severe injury or tissue reaction compared with plastic stents.

scholarly journals The Addition of High Doses of Hyaluronic Acid to a Biphasic Bone Substitute Decreases the Proinflammatory Tissue Response

2019 ◽  
Vol 20 (8) ◽  
pp. 1969 ◽  
Author(s):  
Dominik Sieger ◽  
Tadas Korzinskas ◽  
Ole Jung ◽  
Sanja Stojanovic ◽  
Sabine Wenisch ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Bone Substitute ◽  
Tissue Response ◽  
Control Group ◽  
L929 Cells ◽  
High Doses ◽  
Tissue Reactions ◽  
Inflammatory Macrophages

Biphasic bone substitutes (BBS) are currently well-established biomaterials. Through their constant development, even natural components like hyaluronic acid (HY) have been added to improve both their handling and also their regenerative properties. However, little knowledge exists regarding the consequences of the addition of HY to their biocompatibility and the inflammatory tissue reactions. Thus, the present study was conducted, aiming to analyze the influence of two different amounts of high molecular weight HY (HMWHY), combined with a BBS, on in vitro biocompatibility and in vivo tissue reaction. Established in vitro procedures, using L929 cells, were used for cytocompatibility analyses under the test conditions of DIN EN:ISO 10993-5. For the in vivo part of the study, calvarial defects were created in 20 Wistar rats and subsequently filled with BBS, and BBS combined with two different HMWHY amounts, i.e., BBS + HY(L) and BBS + HY(H). As controls, empty defects were used. Established histological, immunohistochemical, and histomorphometrical methods were applied to analyze the tissue reactions to the three different materials, including the induction of pro- and anti-inflammatory macrophages and multinucleated giant cells (BMGCs). The in vitro results showed that none of the materials or compositions caused biological damage to the L929 cells and can be considered to be non-toxic. The in vivo results showed that only the addition of high doses of HY to a biphasic bone substitute significantly decreases the occurrence of pro-inflammatory macrophages (* p < 0.05), comparable to the numbers found in the control group, while no significant differences within the three study groups for M2-macrophages nor BMGCs were detected. In conclusion, the addition of different amounts of HMWHY does not seem to affect the inflammation response to BBS, while improving the material handling properties.

scholarly journals Physical Properties, Antimicrobial Activity and In Vivo Tissue Response to Apexit Plus

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1171 ◽  
Author(s):  
Roberto Alameda Hoshino ◽  
Guilherme Ferreira da Silva ◽  
Mateus Machado Delfino ◽  
Juliane Maria Guerreiro-Tanomaru ◽  
Mario Tanomaru-Filho ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Physical Properties ◽  
Enterococcus Faecalis ◽  
Subcutaneous Tissue ◽  
Setting Time ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Control Group ◽  
Significant Difference

We investigated the physical properties, antimicrobial activity, and tissue reaction to Apexit Plus in comparison to Sealapex. Flow, radiopacity, setting time, and solubility were evaluated in each material. The antimicrobial activity against Enterococcus faecalis was performed. Polyethylene tubes containing Apexit Plus or Sealapex, and without material (control group) were implanted into the subcutaneous tissue of rats. At 7, 15, 30, and 60 days of implantation, the specimens were paraffin-embedded and the number of inflammatory cells (ICs) and the amount of birefringent collagen (BC) were quantified. The von Kossa reaction followed by immunohistochemistry for detection of alkaline phosphatase (ALP) was also performed. Statistical analysis was performed with ANOVA and Tukey test (p ≤ 0.05). The flow value of Apexit Plus was greater than Sealapex, whereas the radiopacity (3.44 mm Al) was lower than Sealapex (6.82 mm Al). Apexit Plus showed lower solubility and shorter initial and final setting (p < 0.0001), whereas the antimicrobial activity was significantly greater than Sealapex. Although the number of ICs was higher in Apexit Plus (p = 0.0009) at 7 days, no significant difference was detected between Apexit Plus and Sealapex at 15, 30, and 60 days. All groups showed higher values for BC in the capsules over time. ALP-immunolabelled cells were observed, mainly around von Kossa-positive structures, either in the capsules of Apexit Plus or Sealapex. Therefore, our results revealed that Apexit Plus exhibited a greater effectiveness against Enterococcus faecalis and better physical properties than Sealapex, except for the radiopacity. In vivo findings indicate that Apexit Plus is biocompatible and presents potential bioactivity in the subcutaneous tissue.

An effective and biocompatible antibiofilm coating for central venous catheter

2015 ◽  
Vol 61 (5) ◽  
pp. 357-365 ◽  
Author(s):  
Annelisa Farah Silva Paes Leme ◽  
Aline Siqueira Ferreira ◽  
Fernanda Aparecida Oliveira Alves ◽  
Bruna Martinho de Azevedo ◽  
Liza Porcaro de Bretas ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Central Venous Catheter ◽  
Venous Catheter ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Microbiological Analysis ◽  
Central Venous ◽  
Inflammatory Reactions

The aim of this study was to investigate the in vitro and in vivo efficacy and the tissue reaction of an antibiofilm coating composed of xylitol, triclosan, and polyhexamethylene biguanide. The antimicrobial activity was analyzed by a turbidimetric method. Scanning electron microscopy was used to evaluate the antiadherent property of central venous catheter (CVC) fragments impregnated with an antibiofilm coating (I-CVC) in comparison with noncoated CVC (NC-CVC) fragments. Two in vivo assays using subcutaneous implantation of NC-CVC and I-CVC fragments in the dorsal area of rats were performed. The first assay comprised hematological and microbiological analysis. The second assay evaluated tissue response by examining the inflammatory reactions after 7 and 21 days. The formulation displayed antimicrobial activity against all tested strains. A biofilm disaggregation with significant reduction of microorganism’s adherence in I-CVC fragments was observed. In vivo antiadherence results demonstrated a reduction of early biofilm formation of Staphylococcus aureus ATCC 25923, mainly in an external surface of the I-CVC, in comparison with the NC-CVC. All animals displayed negative hemoculture. No significant tissue reaction was observed, indicating that the antibiofilm formulation could be considered biocompatible. The use of I-CVC could decrease the probability of development of localized or systemic infections.

scholarly journals Study of Biointegration and Tissue Reaction of Polyethylene Terephtalate 3D and Polypropylene Surgical Meshes in Rat Model

2018 ◽  
Vol 55 (2) ◽  
pp. 196-200
Author(s):  
Zalan Benedek ◽  
Orsolya Hanko Bauer ◽  
Sorin Sorlea ◽  
Marius Florin Coros ◽  
Tibor Mezei ◽  
...  
Keyword(s):  
Polypropylene Mesh ◽  
Surgical Mesh ◽  
Subcutaneous Tissue ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Control Group ◽  
En Bloc ◽  
3D Mesh ◽  
Polyethylene Terephtalate ◽  
Surgical Meshes

The aim of this experimental study is to compare the biointegration and tissue response to different surgical mesh types, inserted in various layers of the abdominal wall of Wistar rats. After 30 days, the rats were sacrificed and the meshes were removed en bloc with the subcutaneous tissue, muscular layer and peritoneum. Tissue response (fibrosis, inflammation) was measured using quantitative and semi-quantitative morphometry. We observed that polyethylene terephthalate 3D mesh induces significantly more fibrosis compared to polypropylene mesh and the fibrosis is absent or minimal in case of the control group. Tissue reaction, including fibrosis, is reduced around the polypropylene mesh. We also observed that fibrosis is more intense towards aponeurosis and peritoneum. We can conclude that the 3D mesh shows better biointegration if it is used in proper circumstances. It�s well tolerated by the organism if sutured to the aponeurosis and preferable with monofilament stitches.

scholarly journals Ultrasound-triggered on Demand Lidocaine Release Relieves Postoperative Pain

2021 ◽  
Author(s):  
Xiaohong Chen ◽  
Jianfeng Zhang ◽  
Yan Yu ◽  
Haoran Wang ◽  
Genshan Ma ◽  
...  
Keyword(s):  
Postoperative Pain ◽  
Three Dimensional ◽  
Systemic Effect ◽  
Tissue Reaction ◽  
Control Group ◽  
3D Scaffold ◽  
Nerve Blocks ◽  
On Demand

Abstract BackgroundSafe and noninvasive on-demand relief is a crucial and effective treatment for postoperative pain because it considers variable timing and intensity of anesthetics. Ultrasound modulation is a promising technique for this treatment because it allows convenient timed and noninvasive controlled drug release.MethodsWe created an ultrasound-triggered lidocaine (Lido) release platform using an amino acid hydrogel functioning as three dimensional (3D) scaffold material (Lido-PPIX@ER hydrogel). Optimal preparation conditions and ultrasound-triggered parameters were evaluated. In the postoperative pain SD rat model, the Lido-PPIX@ER hydrogel or free lidocaine was administered by subcutaneous injection immediately after making the paw incision. Mechanical hypersensitivity was assessed using calibrated von Frey filaments after an individualized (highly variable) ultrasound-triggered process. The safety of the treatment was also evaluated.ResultsThe Lido-PPIX@ER hydrogel allows control of the timing, intensity and duration of lidocaine (Lido) to relieve postoperative pain. The hydrogel releases Lido due to the elevated reactive oxygen species (ROS) levels generated by PPIX under ultrasound triggering. The optimal ultrasound parameter (0.3 W/cm2, 30 s) was chosen for in vitro and in vivo studies. The Lido-PPIX@ER hydrogel (with lidocaine, 5.6 mg/mL) under individualized ultrasound triggering (every 2 h in the first 12 h, every 4 h for the next 36 h, and then every 6 h until 72 h postsurgery) released lidocaine and provided effective analgesia for more than 72 h. Additionally, the withdrawal threshold was higher than that in the control group at all time points measured. The hydrogel showed repeatable and adjustable ultrasound-triggered nerve blocks in vivo, the duration of which depended on the extent and intensity of insonation. On histopathology, no systemic effect or tissue reaction was observed in the ultrasound-triggered Lido-PPIX@ER hydrogel-treated group.ConclusionsThe Lido-PPIX@ER hydrogel with individualized (highly variable) ultrasound triggering is a convenient and effective method that offers timed and spatiotemporally controlled Lido release to manage postoperative pain.

scholarly journals Adding Two Antimicrobial Glasses to an Endodontic Sealer to Prevent Bacterial Root Canal Reinfection: An In Vivo Pilot Study in Dogs

Antibiotics ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1183
Author(s):  
Álvaro Zubizarreta-Macho ◽  
Cristina Rico-Romano ◽  
María Jesús Fernández-Aceñero ◽  
Jesús Mena-Álvarez ◽  
Belén Cabal ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Root Canal ◽  
Tissue Response ◽  
Control Group ◽  
Root Canal Sealer ◽  
Bacterial Reduction ◽  
Canal Systems ◽  
Histological Results

Current endodontic procedures continue to be unsuccessful for completely removing pathogens present inside the root canal system, which can lead to recurrent infections. In this study, we aimed to assess the antimicrobial capacity and tissue response of two inorganic bactericidal additives incorporated into a paste root canal sealer on contaminated root dentin in vivo. An experimental study was performed in 30 teeth of five Beagle dogs. After inducing microbiological contamination, root canal systems were treated by randomly incorporating one of two antimicrobial additives into a commercial epoxy-amine resin sealer (AH Plus), i.e., G3T glass-ceramic (n = 10) and ZnO-enriched glass (n = 10); 10 samples were randomized as a control group. After having sacrificed the animals, microbiological, radiological, and histological analyses were performed, which were complemented with an in vitro bactericidal test and characterization by field emission scanning electron microscopy. The tested groups demonstrated a non-significant microbiological reduction in the postmortem periapical index values between the control group and the bactericidal glass-ceramic group (p = 0.885), and between the control group and the ZnO-enriched glass group (p = 0.169). The histological results showed low values of inflammatory infiltrate, and a healing pattern characterized by fibrosis in 44.4% of the G3T glass-ceramic and 60.0% of ZnO-enriched glass. Bactericidal glassy additives incorporated in this root canal sealer are safe and effective in bacterial reduction.

scholarly journals Pathological Features of Bovine Pericardium Implanted Into Mice Abdominal Wall after Preservation with Glutaraldehyde or Glycerin

2018 ◽  
Vol 44 (1) ◽  
pp. 7
Author(s):  
Cláudia Borges Costa ◽  
Marta Fernanda Albuquerque da Silva ◽  
Gisele Braziliano de Andrade
Keyword(s):  
Abdominal Wall ◽  
Biological Materials ◽  
Skin Lesions ◽  
Tissue Reaction ◽  
Bovine Pericardium ◽  
Tissue Response ◽  
Control Group ◽  
Tissue Destruction ◽  
Cell Destruction ◽  
Tissue Reactions

Background: Lately, the use of biological materials has been widely indicated in surgical procedures to restore structure and function of injured tissues. Bioimplants require different conservation techniques; among these, glutaraldehyde preservation stands out owing to its higher antimicrobial efficiency as compared to glycerin. In view of the need to determine a concentration of glutaraldehyde that can act as a biocide but do not cause undesirable tissue reactions, this study aimed to identify and quantify gross and microscopic tissue alterations after implantation of bovine pericardium, which was preserved in various concentrations of glutaraldehyde, in the abdominal wall of mice.Materials, Methods & Results: Fresh pericardia from 18 bovines were fractioned into 1cm2 samples and treated with a 98% glycerin solution for 30 days (control group), or 0.625%, 1%, and 1.5% glutaraldehyde solution for 18 days (experimental groups). An abdominal muscle fragment was excised from each mouse, and a 1-cm2 fragment of preserved pericardium was implanted in the area. Sixty mice (n = 15 per treatment) divided into groups were observed for 7, 14, and 30 days, and five animals from each group were euthanized at each time point for gross and microscopic examination. Fragments of the implants and adjacent skin lesions were harvested, fixed in formalin, and processed for routine histology and microscopic analysis. Both the type of inflammatory infiltrate and the repair process of the tissue response were similar between the groups that received glycerin-preserved pericardium and those that were subjected to pericardium preserved with 0.625% glutaraldehyde. Animals that received 1% glutaraldehyde-preserved implants and were examined 30 days thereafter exhibited a chronic, intense reaction with fibrosis and necrosis of the abdominal wall muscles, as well as calcification and presence of giant cells, when compared to the animals examined at 7 and 14 days in the same treatment group. These changes were also present and more intense in animals that received 1.5% glutaraldehyde-preserved pericardium examined at 14 and 30 days later, with tissue destruction and impaired incorporation of the implant into the adjacent muscle tissue.Discussion: The continuous cell destruction observed in animals treated with implants preserved with 1% or 1.5% glutaraldehyde is a hallmark of chronic inflammation, since several inflammatory cell molecules contribute to this lesion. A cycle is created: continuous degradation sustains inflammation, and inflammatory molecules contribute to the process of cell destruction. Consequently, we conclude that the use of glutaraldehyde at concentrations of 1 or 1.5% is not feasible for preservation of biological materials. Tissue repair was chronologically more effective in the group treated with glycerinpreserved implants, since animals treated with glutaraldehyde-preserved implants needed a longer period to restore due to presence of a persistent inflammatory response, immunogenicity, calcification, and deficient remodeling.  The ideal preservative for biological materials should not cause chronic and/or intense inflammatory reaction in order to preserve the implant’s structure and allow its perfect incorporation into the tissue, even if the chosen preservative is flexible and exhibits disinfectant properties. Therefore, we conclude that glutaraldehyde at concentrations of 0.625% to 1% is suitable as a preservative for biomaterials because the tissue reaction it causes is tolerable; additionally, glutaraldehyde at concentrations close to 1% has been described to have sterilizing properties.

scholarly journals In vitro and in vivo response of composites based on chitosan, hydroxyapatite and collagen

2019 ◽  
Vol 42 ◽  
pp. e41102
Author(s):  
Maurício Bordini do Amaral ◽  
Rommel Bezerra Viana ◽  
Katúcia Bezerra Viana ◽  
Cristina Aparecida Diagone ◽  
Aline Bassi Denis ◽  
...  
Keyword(s):  
Vero Cells ◽  
In Vitro Cytotoxicity ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Bone Collagen ◽  
Biological Behavior ◽  
Toxicity Tests ◽  
Bovine Bone

 The goal of this study was to evaluate the in vitro cellular toxicity and biological behavior of new bone graft composites after subcutaneous implantation during remodeling and wound-healing processes. We developed composites based on hydroxyapatite (obtained by deproteinizing bovine bone), collagen (obtained from bovine tendon) and chitosan (obtained from gladii of the squid species Loligo), that were characterized by different techniques (X-ray, FT-IR, Thermogravimetry, DSC and SEM). Three biomaterials were evaluated here: B1 (collagen/chitosan/hydroxyapatite), B2 (collagen/hydroxyapatite) B3 (collagen/hydroxyapatite). For in vitro cytotoxicity tests, two cell lines were used: HEp human larynx tumor cells (ATCC-CCL-23) and VERO cells from African green monkey (Cercopithecus aethiops). These toxicity tests demonstrated that the evaluated composites are not toxic. In biocompatibility tests, the results of a histological analysis showed that all three biomaterials present a low inflammatory tissue reaction. The tissue response was most favorable for sample B3, followed by B2 and B1, in that order. Based on these results, we conclude that all three biomaterials show good biocompatibility and no evidence of cytotoxicity; thus, these materials represent good candidates for tissue and graft engineering for use in bone regeneration.

Sign in / Sign up

Export Citation Format

Share Document