Surgical Sutures with Porous Sheaths for the Sustained Release of Growth Factors.
Ontology highlight
ABSTRACT:
SUBMITTER: Li J
PROVIDER: S-EPMC4938160 | biostudies-literature | 2016 Jun
REPOSITORIES: biostudies-literature
Publications
Surgical Sutures with Porous Sheaths for the Sustained Release of Growth Factors.
Li Jianhua J Linderman Stephen W SW Zhu Chunlei C Liu Hong H Thomopoulos Stavros S Xia Younan Y
Advanced materials (Deerfield Beach, Fla.) 20160405 23
Surgical sutures with highly porous sheaths are developed using a swelling and freeze-drying procedure without compromising their mechanical properties. The modified sutures show a high capacity for loading biofactors and are able to release the loaded biofactors in a sustained manner. ...[more]
Similar Datasets
Project description:The tension in a suture is an important factor in the process of wound healing. If there is too much tension in the suture, the blood flow is restricted and necrosis can occur. If the tension is too low, the incision opens up and cannot heal properly. The purpose of this paper is to describe the design and evaluation of the Stitch Force (SF) sensor and the Hook-In Force (HIF) sensor. These sensors were developed to measure the force on a tensioned suture inside a closed incision and to measure the pulling force used to close the incision. The accuracy of both sensors is high enough to determine the relation between the force in the thread of a stitch and the pulling force applied on the suture by the physician. In a pilot study, a continuous suture of 7 stitches was applied on the fascia of the abdominal wall of multiple pigs to study this relationship. The results show that the max force in the thread of the second stitch drops from 3 (SD 1.2) to 1 (SD 0.3) newton after the 4(th) stitch was placed. During placement of the 5(th), 6(th) and 7(th) stitch, the force in the 2(nd) stitch was not influenced anymore. This study indicates that in a continuous suture the force in the thread remains constant up to more than 3 stiches away from the pulled loose end of the suture. When a force feedback tool is developed specially for suturing in surgery on patients, the proposed sensors can be used to determine safety threshold for different types of tissue and sutures.
| S-EPMC3871579 | biostudies-literature
Project description:Wound closure with surgical sutures is a critical challenge for flexible endoscopic surgeries. Substantial efforts have been introduced to develop functional and smart surgical sutures to either monitor wound conditions or ease the complexity of knot tying. Although research interests in smart sutures by soft robotic technologies have emerged for years, it is challenging to develop a soft robotic structure that possesses a similar physical structure as conventional sutures while offering a self-tightening knot or anchor to close the wound. This paper introduces a new concept of smart sutures that can be programmed to achieve desired and uniform tension distribution while offering self-tightening knots or automatically deploying secured anchors. The core technology is a soft hydraulic artificial muscle that can be elongated and contracted under applied fluid pressure. Each suture is equipped with a pressure locking mechanism to hold its temporary elongated state and to induce self-shrinking ability. The puncturing and holding force for the smart sutures with anchors are examined. Ex-vivo experiments on fresh porcine stomach and colon demonstrate the usefulness of the new smart sutures. The new approaches are expected to pave the way for the further development of smart sutures that will benefit research, training, and commercialization in the surgical field.
| S-EPMC8599709 | biostudies-literature
Project description:Interventions: Group 1: The radioembolization in hepatic malignancies is a routine clinical procedure. Serum samples for growth factor determination from peripheral venous blood are taken at three points in time - before therapy, after the first radioembolization and before the second radioembolization.
Study procedure ends after the third blood sample has been taken.
The second therapy for SIRT and the follow-up examinations belong to the scope of routine clinical procedures/follow-up.
Primary outcome(s): Evaluation of growth hormone release as a prognostic marker for overall survival after local ablative radioembolization therapy (SIRT) of hepatic malignancies.
Study Design: Allocation: N/A: single arm study; Masking: Open (masking not used); Control: uncontrolled; Assignment: single; Study design purpose: basic science
| 2721073 | ecrin-mdr-crc
Project description:Recent growth factor, cell, and scaffold-based experimental interventions for intrasynovial flexor tendon repair have demonstrated therapeutic potential in rodent models. However, these approaches have not achieved consistent functional improvements in large animal trials due to deleterious inflammatory reactions to delivery materials and insufficient induction of targeted biological healing responses. In this study, we achieved porous suture-based sustained delivery of connective tissue growth factor (CTGF) into flexor tendons in a clinically relevant canine model. Repairs with CTGF-laden sutures were mechanically competent and did not show any evidence of adhesions or other negative inflammatory reactions based on histology, gene expression, or proteomics analyses at 14 days following repair. CTGF-laden sutures induced local cellular infiltration and a significant biological response immediately adjacent to the suture, including histological signs of angiogenesis and collagen deposition. There were no evident widespread biological effects throughout the tendon substance. There were significant differences in gene expression of the macrophage marker CD163 and anti-apoptotic factor BCL2L1; however, these differences were not corroborated by proteomics analysis. In summary, this study provided encouraging evidence of sustained delivery of biologically active CTGF from porous sutures without signs of a negative inflammatory reaction. With the development of a safe and effective method for generating a positive local biological response, future studies can explore additional methods for enhancing intrasynovial tendon repair. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2052-2063, 2018.
| S-EPMC6013340 | biostudies-literature
Project description:Sutures can cause challenging surgical site infections, due to capillary effects resulting in bacteria permeating wounds. Anti-microbial sutures may avoid these complications by inhibiting bacterial pathogens. Recently, first triclosan-resistances were reported and therefore alternative substances are becoming clinically relevant. As triclosan alternative chlorhexidine, the "gold standard" in oral antiseptics was used. The aim of the study was to optimize novel slow release chlorhexidine coatings based on fatty acids in surgical sutures, to reach a high anti-microbial efficacy and simultaneously high biocompatibility. Sutures were coated with chlorhexidine laurate and chlorhexidine palmitate solutions leading to 11, 22 or 33 µg/cm drug concentration per length. Drug release profiles were determined in aqueous elutions. Antibacterial efficacy against Staphylococcus aureus was assessed in agar diffusion tests. Biocompatibility was evaluated via established cytotoxicity assay (WST-1). A commercially triclosan-containing suture (Vicryl Plus), was used as anti-microbial reference. All coated sutures fulfilled European Pharmacopoeia required tensile strength and proved continuous slow drug release over 96 hours without complete wash out of the coated drug. High anti-microbial efficacy for up to 5 days was observed. Regarding biocompatibility, sutures using 11 µg/cm drug content displayed acceptable cytotoxic levels according to ISO 10993-5. The highest potential for human application were shown by the 11 µg/cm chlorhexidine coated sutures with palmitic acid. These novel coated sutures might be alternatives to already established anti-microbial sutures such as Vicryl Plus in case of triclosan-resistance. Chlorhexidine is already an established oral antiseptic, safety and efficacy should be proven for clinical applications in anti-microbial sutures.
| S-EPMC4077814 | biostudies-other
Project description:Silk sericin, a water-soluble glue-like protein, is extensively used as a biomaterial due to its biocompatibility, hydrophilicity, biodegradability, and adequate resource. In addition, hydroxyapatite-based drug carriers are functionally efficient for drug or gene delivery due to their biodegradability, biocompatibility and easy metabolism in vivo. Herein, for the first time, this study used sericin, from a wild silkworm called Antheraea pernyi (A. pernyi), as a template to nucleate hydroxylapatite (HAp) nano-needles and form porous sericin-HAp nanocomposite microspheres as an anticancer drug carrier. Specifically, A. pernyi sericin (AS) was incubated in 1.5× simulated body fluid to induce the formation of porous AS/HAp microspheres in situ. Doxorubicin (DOX) loading and release assays proved that the microspheres exhibited pH-dependent controlled and sustained release of DOX. In particular, the microspheres can selectively release DOX at a higher rate at the acidic conditions typical for tumor microenvironment than at the physiological conditions typical for normal tissues, which will potentially reduce the side effect of the cancer drugs in normal tissues. Cancer cell toxicity assay, cancer cell imaging and intracellular DOX distribution assay provided further evidence to support the pH-dependent controlled and sustained release of DOX to cancer cells from the microspheres. Our work has demonstrated a biomimetic strategy for the design and synthesis of silk protein-based drug carriers that can be potentially employed in drug delivery and regenerative medicine.
| S-EPMC5687098 | biostudies-literature
Project description:A controlled and observable drug delivery system that enables long-term local drug administration is reported. Biodegradable and biocompatible drug-loaded porous Si microparticles were prepared from silicon wafers, resulting in a porous 1-dimensional photonic crystal (rugate filter) approx. 12 ?m thick and 35 ?m across. An organic linker, 1-undecylenic acid, was attached to the Si-H terminated inner surface of the particles by hydrosilylation and the anthracycline drug daunorubicin was bound to the carboxy terminus of the linker. Degradation of the porous Si matrix in vitro was found to release the drug in a linear and sustained fashion for 30 d. The bioactivity of the released daunorubicin was verified on retinal pigment epithelial (RPE) cells. The degradation/drug delivery process was monitored in situ by digital imaging or spectroscopic measurement of the photonic resonance reflected from the nanostructured particles, and a simple linear correlation between observed wavelength and drug release was observed. Changes in the optical reflectance spectrum were sufficiently large to be visible as a distinctive red to green color change.
| S-EPMC3025697 | biostudies-literature
Project description:In this study, porous gelatin microspheres (GMSs) were constructed to improve the neuroprotective effect of basic fibroblast growth factor (bFGF) on spinal cord injury. GMSs were prepared by a W/O emulsion template, followed by cross-linking, washing and drying. The particle sizes and surface porosity of the blank GMSs were carefully characterized by scan electronic microscopy. The blank GMSs have a mean particle size of 35μm and theirs surface was coarse and porous. bFGF was easily encapsulated inside the bulk GMSs through diffusion along the porous channel. 200μg of bFGF was completely encapsulated in 100mg of GMSs. The bFGF-loaded GMSs displayed a continuous drug release pattern without an obvious burst release over two weeks in vitro. Moreover, the therapeutic effects of bFGF-loaded GMSs were also evaluated in spinal cord injury rat model. After implantation of bFGF-loaded GMSs, the recovery of the motor function of SCI rats were evaluated by behavioral score and foot print experiment. The motor function of SCI rats treated with bFGF-loaded GMSs was more obvious than that treated with free bFGF solution (P<0.05). At the 28th days after treatment, rats were sacrificed and the injured spinal were removed for histopathological and apoptosis examination. Compared with treatment with free bFGF solution, treatment with bFGF-loaded GMSs resulted in a less necrosis, less infiltration of leukocytes, and a reduced the cavity ratio and less apoptotic cells in injured spinal(P<0.01), indicating its better therapeutic effect. Implantable porous GMSs may be a potential carrier to deliver bFGF for therapy of spinal cord injury.
| S-EPMC5349659 | biostudies-literature
Project description:Hydrogel nanomaterials, especially those that are of non-human and non-animal origins, have great potential in biomedical and pharmaceutical sciences due to their versatility and inherent soft-tissue like properties. With the ability to simulate native tissue function, hydrogels are potentially well suited for cellular therapy applications. In this study, we have fabricated nanofibrillar cellulose-alginate (NFCA) suture coatings as biomedical devices to help overcome some of the limitations related to cellular therapy, such as low cell survivability and distribution out of target tissue. The addition of sodium alginate 8% (w/v) increased the NFCA hydrogel viscosity, storage and loss moduli by slightly under one order of magnitude, thus contributing significantly to coating strength. Confocal microscopy showed nearly 100% cell viability throughout the 2-week incubation period within and on the surface of the coating. Additionally, typical morphologies in the dual cell culture of spheroid forming HepG2 and monolayer type SK-HEP-1 were observed. Twelve out of 14 NFCA coated surgical sutures remained intact during the suturing operation with various mice and rat tissue; however, partial peeling off was observed in 2 of the coated sutures. We conclude that NFCA suture coatings could perform as cell-carrier systems for cellular based therapy and post-surgical treatment.
| S-EPMC5567492 | biostudies-literature
Project description:Hair regeneration has long captured researchers' attention because alopecia is a common condition and current therapeutic approaches have significant limitations. Dermal papilla (DP) cells serve as a signaling center in hair follicles and regulate hair formation and cycling by paracrine secretion. Secreted EVs are important signaling mediators for intercellular communication, and DP-derived extracellular vesicles (DP-EVs) may play an important role in hair regeneration. However, the instability of EVs in vivo and their low long-term retention after transplantation hinder their use in clinical applications. Methods: Human DP-EVs were encapsulated in partially oxidized sodium alginate (OSA) hydrogels, yielding OSA-encapsulated EVs (OSA-EVs), which act as a sustained-release system to increase the potential therapeutic effect of DP-EVs. The ability of the OSA-EVs to protect protein was assessed. The hair regeneration capacity of OSA-EVs, as well as the underlying mechanism, was explored in hair organ culture and a mouse model of depilation. Results: The OSA-EVs were approximately 100 ?m in diameter, and as the hydrogel degraded, DP-EVs were gradually released. In addition, the hydrogel markedly increased the stability of vesicular proteins and increased the retention of EVs in vitro and in vivo. The OSA-EVs significantly facilitated proliferation of hair matrix cells, prolonged anagen phase in cultured human hairs, and accelerated the regrowth of back hair in mice after depilation. These effects may be due to upregulation of hair growth-promoting signaling molecules such as Wnt3a and ?-catenin, and downregulation of inhibitory molecule BMP2. Conclusion: This study demonstrated that OSA hydrogels promote the therapeutic effects of DP-EVs, and indicate that our novel OSA-EVs could be used to treat alopecia.
| S-EPMC6956798 | biostudies-literature