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A Study of Mesh Implants Coated with a Biocompatible Polyhydroxyalkanoates Layer
Published in Tatiana G. Volova, Yuri S. Vinnik, Ekaterina I. Shishatskaya, Nadejda M. Markelova, Gennady E. Zaikov, Natural-Based Polymers for Biomedical Applications, 2017
Tatiana G. Volova, Yuri S. Vinnik, Ekaterina I. Shishatskaya, Nadejda M. Markelova, Gennady E. Zaikov
Achievement of better outcomes of surgical interventions in abdominal surgery is impossible without using new materials. For instance, surgical treatment of the patients with postoperative ventral hernias of the anterior abdominal wall has been one of the challenges in abdominal surgery. Hernia formation is a complex condition, caused by imbalance between intra-abdominal pressure and resistivity of the abdominal wall. Surgery using local tissues does not ensure stable improvement. The employment of tension-free techniques in surgeries of the postoperative ventral hernias and the use of synthetic materials was a revolution in hernia repair. Meshes can be implanted in super-aponeurotic, sub-aponeurotic, and intramuscular positions. However, plastic surgery of the anterior abdominal wall involving the use of synthetic allografts is a complicated surgical procedure and may cause the development of postoperative complications, both specific and nonspecific ones. Support meshes of a new generation are needed for hernia repair, which is one of the most common surgical operations, amounting to 10–15% of all surgeries. More than 20 million herniotomies are performed in the world, with recurrent hernias appearing in 10–15% (Fedorov and Adamyan, 2000). So-called barrier techniques are being developed to prevent surgical adhesions. Materials used to prepare such meshes should be able to prevent adhesions to internal organs, be resistant to infection, be mechanically strong, and tolerate long-term tension without deep scarring and encapsulation.
Biobased polymer SF/PHBV composite nanofiber membranes as filtration and protection materials
Published in The Journal of The Textile Institute, 2023
The research on PHA fiber is mainly concentrated in the fields of melt spinning and electrospinning. The melt spinning process of PHA only exists in the laboratory stage due to its defects in crystallization and thermal stability. PHBV has been explored a lot in PHAs. Ohura et al. (1999) obtained PHBV fiber with a breaking strength of 183 MPa. Yamamoto et al. (1997) studied the influence of drafting and annealing processes on the structure and properties of PHBV fibers and obtained PHBV fibers with a breaking strength of 210 MPa. The mechanical properties of PHBV fibers obtained by the above methods were all poor. Conventional melt spinning technology can not obtain PHA fibers with good mechanical properties. Generally, it is necessary to adopt special spinning and drawing processes or through blending modification to improve the spinnability and ultimately improve the mechanical properties of the fiber. The preparation process of PHBV electrospun nanofiber is relatively simple and has many applications in biomedicine. Wu and Wang (2018) prepared a bio-based electrospun polyhydroxyalkanoate (PHA) nanofiber by dissolving PHA with dichloromethane, but the fiber-forming effect of the fiber was not particularly good; there were adhesions between each other. Castro-Mayorga et al. Castro-Mayorga et al., Castro-Mayorga et al., (2016) produced antimicrobial polyhydroxyalkanoate materials containing in situ-stabilized silver nanoparticles by electrospinning coating technique, and the fiber diameter was large and uneven. Solvent selection and spinning process parameters have a greater impact on fiber morphology.
Polycaprolactone-gelatin membrane as a sealant biomaterial efficiently prevents postoperative anastomotic leakage with promoting tissue repair
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Gyeongjin Joo, Tamanna Sultana, Sohanur Rahaman, Sang Ho Bae, Hae Il Jung, Byong-Taek Lee
Male Sprague-Dawley rats (Rattus norvegicus, 200 to 250 g each) were purchased from the animal center (Dayoon, South Korea). The institutional animal committee of Soonchunhyang University, South Korea issued guidelines for animal maintenance and approved experiment accordingly. In vivo testing was performed by cutting the sample into squares each measuring 1 cm × 1 cm size, and each side of the membrane was sterilized under UV light for 1 h. In this study, 8-week-old male rats were used. The experiment was divided into two groups (control and sample, 2 weeks of study) (n = 6/group). Vaporized isoflurane (TERRELLTM, Piramal Critical Care Inc., USA) mixed with oxygen was used for inhalation in a special chamber. A mask was placed over the face of rats to maintain anesthesia throughout the surgery. After anesthesia, the shaved abdomen was disinfected with povidone iodine solution and cut vertically. A 5 mm defect on the caecum was made. The defected caecum was sutured in the control group. The experimental group was treated with membrane on the sutured caecum. The abdomen and peritoneum were finally closed with sutures. Later, the animals were held under ambient environmental conditions of food and water. During 1 and 2 weeks post-surgery, the rats were euthanized with diethyl ether. The incisions were reopened, examined for adhesions, leakage, or healing followed by grading of inflammation and vascularization (intensity increased in ascending way).
Treatment for lumbar spinal stenosis in elderly patients using percutaneous endoscopic lumbar discectomy combined with postoperative three-dimensional traction
Published in Expert Review of Medical Devices, 2019
Dexin Hu, Jun Fei, Genjun Chen, Yongjie Yu, Zhen Lai
Traditional traction is the use of force and reaction force, focusing on the affected area. As traditional traction has some flaws, it is helpful to use the more technologically advanced three-dimensional traction [23–25]. Three-dimensional traction is considered to be the prior way of non-surgical approach for the treatment of lumbar spinal stenosis [26]. It could alleviate nerve adhesions, correct the intervertebral three-dimensional direction, and increase the intervertebral space to create a negative pressure in the narrow intervertebral foramen. It may also reduce the pressure of the spinal canal, increase blood circulation near the spinal canal, and improve nerve root oxygen supply levels [1,27]. In this way, it may reduce the inflammation caused by intervertebral joint around the ligaments and muscle congestion [1,27]. Normal sagittal parameters are 57.4 ± 13.7 for LL, 60.5 ± 15.2 for PI, and 17.7 ± 9.1 for SS. In this study, all 180 patients had lower parameters for LL, PI, and SS and higher parameters for PT before the operation. According to the difference in imaging parameters before and after surgery, the patients in PELD combined with postoperative three-dimensional traction group experienced a better outcome than those in the other two groups.