Biological Patch Research Articles

Biological Patch in the Repair of Rotator Cuff Tears: Functional and Clinical Evaluation of Twenty-Three Cases with a Mean Follow-Up of Six Years.

Background: Rotator cuff (RC) repair leads to less than optimal results when dealing with massive lesions, so the use of scaffolds as biological support has been proposed to improve RC repair site biology. The present study aims to evaluate the clinical and radiographical outcomes of a series of patients suffering from massive or irreparable RC tears treated with patch (porcine or human scaffolds) repair (augmentation or bridging). Methods: Twenty-three patients with a minimum follow-up of 24 months were subjectively, clinically, and radiographically assessed before and after surgery. Three different patient-related outcome measurements (PROMs) (American Shoulder and Elbow Surgeons score, Constant score, visual analog scale) were used for the subjective and clinical evaluation, while plain radiographs and magnetic resonance imaging where employed for radiographical follow-up. Results: Regardless of the technique (augmentation or bridging) or type of scaffold (porcine or human) employed, at follow-up, all patients experienced a statistically significant improvement in all PROMs and clinically. Conclusions: Patch repair represents a valid salvage procedure in massive or irreparable RC tears, improving the quality of life and eventually delaying the need for prosthetic replacement.

Biomechanical and histological evaluation of a prototype bovine pericardial patch for veterinary abdominal surgery: An approximation study

In veterinary medicine, especially within large animal medical and surgical clinics, addressing cavitary defects is a primary concern. In bovines, umbilical hernias are the most common defect, and surgical repair often necessitates the use of prosthetic materials. However, there is a high rate of recurrence with sutures or synthetic meshes, largely due to tissue contamination. The development of biological patches for such repairs is still in its early stages in veterinary medicine, with no commercially tested prototypes available in Argentina. Tissues derived from the extracellular matrix are considered for this purpose, with bovine pericardium standing out due to its architectural characteristics and mechanical properties. For an ideal membrane, the pericardium must retain its biomechanical properties while being unreactive and safe for the host. This study aimed to biomechanically and histologically characterize a bovine pericardium patch through all stages of processing. The treatment involved fixation with 0.5 % glutaraldehyde, immersion in an antibiotic/antimycotic solution, and detoxification and storage in a 98 % sterile glycerin solution, with three sodium phosphate-buffered washes between steps. Histological examinations and stress-strain tests were performed at each processing stage, using native pericardium as a control. Despite some minor modifications in the histological and mechanical properties, the final patches appear to be a viable alternative for resolving cavitary defects.

Clinical efficacy of autologous biological patch in preventing rectovaginal fistula after pelvic exenteration

Clinical efficacy of autologous biological patch in preventing rectovaginal fistula after pelvic exenteration

An antibacterial biologic patch based on bacterial cellulose for repair of infected hernias

Infection-associated complications and repair failures and antibiotic resistance have emerged as a formidable challenge in hernia repair surgery. Consequently, the development of antibiotic-free antibacterial patches for hernia repair has become an exigent clinical necessity. Herein, a GBC/Gel/LL37 biological patch (biopatch) with exceptional antibacterial properties is fabricated by grafting 2-Methacryloyloxyethyl trimethylammonium chloride (METAC), a unique quaternary ammonium salt with vinyl, onto bacterial cellulose (GBC), followed by compounding with gelatin (Gel) and LL37. The GBC/Gel/LL37 biopatch exhibits stable swelling capacity, remarkable mechanical properties, flexibility, and favorable biocompatibility. The synergistic effect of METAC and LL37 confers upon the GBC/Gel/LL37 biopatch excellent antibacterial efficacy against Staphylococcus aureus and Escherichia coli, effectively eliminating invading bacteria without the aid of exogenous antibiotics in vivo while significantly reducing local acute inflammation caused by infection. Furthermore, the practical efficacy of the GBC/Gel/LL37 biopatch is evaluated in an infected ventral hernia model, revealing that the GBC/Gel/LL37 biopatch can prevent the formation of visceral adhesions, facilitate the repair of infected ventral hernia, and effectively mitigate chronic inflammation. The prepared antibacterial GBC/Gel/LL37 biopatch is very effective in dealing with the risk of infection in hernia repair surgery and offers potential clinical opportunities for other soft injuries, exhibiting considerable clinical application prospects.

A wearable electrostimulation-augmented ionic-gel photothermal patch doped with MXene for skin tumor treatment

A wearable biological patch capable of producing multiple responses to light and electricity without interfering with daily activities is highly desired for skin cancer treatment, but remains a key challenge. Herein, the skin-mountable electrostimulation-augmented photothermal patch (eT-patch) comprising transparent ionic gel with MXene (Ti3C2Tx) doping is developed and applied for the treatment of melanoma under photostimulation at 0.5 W/cm2. The eT-patch designed has superior photothermal and electrical characteristics owing to ionic gels doped with MXene which provides high photothermal conversion efficiency and electrical conductivity as a medium. Simultaneously, the ionic gel-based eT-patch having excellent optical transparency actualizes real-time observation of skin response and melanoma treatment process under photothermal and electrical stimulation (PES) co-therapy. Systematical cellular study on anti-tumor mechanism of the eT-patch under PES treatment revealed that eT-patch under PES treatment can synergically trigger cancer cell apoptosis and pyroptosis, which together lead to the death of melanoma cells. Due to the obvious advantages of relatively safe and less side effects in healthy organs, the developed eT-patch provides a promising cost-effective therapeutic strategy for skin tumors and will open a new avenue for biomedical applications of ionic gels.

Biologically Enhanced Patch in the Healing and Mechanical Stability of Rotator Cuff Tears.

Biological patches have emerged as promising adjuncts in the surgical management of rotator cuff tears, aiming to enhance tissue healing and biomechanical properties of repaired tendons. These patches, derived from human or animal sources such as dermis or small intestinal submucosa, undergo mechanical and pathological changes within the rotator cuff environment post-implantation. These patches provide structural reinforcement to the repair site, distributing forces more evenly across the tendon and promoting a gradual load transfer during the healing process. This redistribution of forces helps alleviate tension on the repaired tendon and surrounding tissues, potentially reducing the risk of re-tears and improving overall repair integrity. Moreover, biological patches serve as scaffolds for cellular infiltration and tissue ingrowth, facilitating the recruitment of cells and promoting collagen synthesis. The integration of these patches into the host tissue involves a cascade of cellular events, including inflammation, angiogenesis, and matrix remodeling. Inflammatory responses triggered by patch implantation contribute to the recruitment of immune cells and the release of cytokines and growth factors, fostering a microenvironment conducive to tissue repair. However, despite their potential benefits, the long-term efficacy and durability of biological patches in rotator cuff repair remain areas of ongoing research and debate. Further studies are needed to elucidate the optimal patch characteristics, surgical techniques, and rehabilitation protocols to maximize clinical outcomes and minimize complications in rotator cuff surgery.

Our experiences with carotid artery endarterectomy operations

Aims: In this retrospective study, we aimed to presentour experiences with patients undergoing carotid endarterectomy (CEA) operations. Methods: Between January 2011 and January 2021, a total of 88 patients (27 female, 61 male, mean age; 68.9 ± 8.7 and 41-88 years old) who underwent CEA were included in the study.Patients' files were reviewed.Bilateral CEA was performed in 2 of the patients. The complaints and demographic characteristics of the patients are shown in Table 1 and Table 2, respectively. Coronary artery bypass grafting (CABG) was also performed in 10 (8 of them simultaneously and 2 of them 1 month later)of the patients. In one of these simultaneously operated patients, aortic valve replacement was performed in addition to CEA and CABG. On the other hand, the operation was terminated due to the development of intraoperative sudden cardiac arrest in 2 patients. Results: Polytetrafluoroethylene patch, biological patch, Dacron patch, and great saphenous vein patch were used in 1, 1, 3,and 40 patients, respectively, while the CEA site was primarily closed in 43 patients.Characteristic features ofthe CEA operations are shown in Table 3. Also, complications of CEA surgery are shown in Table 4.In-hospital mortality was detected in 3 patients. Conclusion: The early results of our CEA operations are in line with the literature.

Research Advances in Medical Materials and Products for Soft Tissue Repairs

Soft tissue is an indispensable tissue in human body. It plays an important role in protecting the body from external physical, chemical or biological factors. Mild soft tissue injuries can self-heal, while severe soft tissue injuries may require related treatment. Natural polymers (such as chitosan, hyaluronic acid, and collagen) and synthetic polymers (such as polyethylene glycol and polylactic acid) exhibit good biocompatibility, biodegradability and low toxicity. It can be used for soft tissue repairs for antibacterial, hemostatic and wound healing purposes. Their related properties can be enhanced through modification or preparation of composite materials. Commonly used soft tissue repairs include wound dressings, biological patches, medical tissue adhesives, and tissue engineering scaffolds. This study introduces the properties, mechanisms of action and applications of various soft tissue repair medical materials, including chitosan, hyaluronic acid, collagen, polyethylene glycol and polylactic acid, and provides an outlook on the application prospects of soft tissue repair medical materials and products.

Long Term Follow Up of Dacron Versus Bovine Pericardium For Carotid Endarterectomy With Patch Angioplasty: a Retrospective Cohort Study

Objective: Patch angioplasty during carotid endarterectomy (CEA) is commonly used to treat carotid artery stenosis. Various patch materials are available, including venous, Dacron, bovine pericardium, and polytetrafluoroethylene. However, the choice of which patch to use is still a matter of debate. Autologous venous material has disadvantages such as wound related problems and a prolonged intervention time. This is due to the harvesting of the vein. These limitations can be bypassed when synthetic or biological patches are used, which are immediately available. Therefore, the aim of this study was to compare the long term outcomes in patients who received a CEA with either a bovine pericardial patch (BPP) or a Dacron patch.

3D-bioprinted double-crosslinked angiogenic alginate/chondroitin sulfate patch for diabetic wound healing

Improving chronic wound healing remains a challenge in the clinical practice. In this study, we developed double-crosslinked angiogenic 3D-bioprinted patches for diabetic wound healing by the photocovalent crosslinking of vascular endothelial growth factor (VEGF) using ultraviolet (UV) irradiation. 3D printing technology can precisely customize the structure and composition of patches to meet different clinical requirements. The biological polysaccharide alginate and chondroitin sulfate methacryloyl were used as biomaterials to construct the biological patch, which could be crosslinked using calcium ion crosslinking and photocrosslinking, thereby improving its mechanical properties. More importantly, acrylylated VEGF could be easily and rapidly photocrosslinked under UV irradiation, which simplified the step of chemically coupling growth factors and prolonged VEGF release time. These characteristics suggest that 3D-bioprinted double-crosslinked angiogenic patches are ideal candidates for diabetic wound healing and other tissue engineering applications.

Tissue-Adhesive Decellularized Extracellular Matrix Patches Reinforced by a Supramolecular Gelator to Repair Abdominal Wall Defects.

Implantation of surgical meshes composed of synthetic and biological materials has been applied for abdominal wall defect repair. Despite many efforts, there are no reliable meshes that fully satisfy clinical requirements because of their lack of biodegradability, mechanical strength, and tissue-adhesive properties. Here, we report biodegradable, decellularized extracellular matrix (dECM)-based biological patches to treat abdominal wall defects. By incorporating a water-insoluble supramolecular gelator that forms physical cross-linking networks through intermolecular hydrogen bonding, dECM patches were reinforced to improve mechanical strength. Reinforced dECM patches possessed higher tissue adhesion strength and underwater stability compared with the original dECM because of enhanced interfacial adhesion strength. In vivo experiments using an abdominal wall defect rat model showed that reinforced dECM patches induced collagen deposition and the formation of blood vessels during material degradation, and the accumulation of CD68-positive macrophages was suppressed compared to nonbiodegradable synthetic meshes. Tissue-adhesive and biodegradable dECM patches with improved mechanical strength by a supramolecular gelator have enormous potential for use in the repair of abdominal wall defects.

A Comparison of Vessel Patch Materials in Tetralogy of Fallot Patients Using Virtual Surgery Techniques.

Tetralogy of Fallot (ToF) is characterized by stenosis causing partial obstruction of the right ventricular outflow tract, typically alleviated through the surgical application of a vessel patch made from a biocompatible material. In this study, we use computational simulations to compare the mechanical performance of four patch materials for various stenosis locations. Nine idealized pre-operative ToF geometries were created by imposing symmetrical stenoses on each of three anatomical sub-regions of the pulmonary arteries of three patients with previously repaired ToF. A virtual surgery methodology was implemented to replicate the steps of vessel de-pressurization, surgical patching, and subsequent vessel expansion after reperfusion. Significant differences in patch average stress (p < 0.001) were found between patch materials. Biological patch materials (porcine xenopericardium, human pericardium) exhibited higher patch stresses in comparison to synthetic patch materials (Dacron and PTFE). Observed differences were consistent across the various stenosis locations and were insensitive to patient anatomy.

High‐resolution measurements of the epipelagic and mesopelagic ocean by a profiling vehicle equipped with environmental sensors and a broadband echosounder

AbstractCollecting detailed surveys of the environmental and biological distributions in the epipelagic and mesopelagic ocean is important for understanding the basic processes that govern these expansive habitats and influence the earth system at large. Common ocean sampling platforms (e.g., net systems, moored, and shipboard sensors), are often unable to resolve marine biota at scales comparable to the variability associated with their own behavior or that of their physical environment. Newer approaches using mobile robotic systems carrying multiple environmental sensors have enabled detailed interrogation of the fine and sub‐mesoscale distribution of animals and have provided more context for the water column structure. We integrated a dual‐frequency broadband split‐beam echosounder (Simrad EK80 with 70 and 200 kHz transducers) into the Wire Flyer profiling vehicle to achieve concurrent hydrographic and acoustic sections in the midwater environment (0–1000 m) at novel scales. The Wire Flyer provides high‐resolution repeat profiling (0–2.5 m s−1 up and down velocity) within specified water column depth bands typically spanning 300–400 m. This system can provide acoustic backscatter data at depths unavailable to shipboard surveys due to attenuation limits and can be operated in tandem with conventional shipboard echosounders to provide overlapping acoustic coverage with concurrent hydrographic sections. The side‐looking transducer orientation, as opposed to the traditional vertically oriented arrangement on ships, samples orthogonal to the vehicle's profiling survey path and provides a direct measurement of animal distributions in the horizontal. The processed data have demonstrated the system's capacity to track migrating layers and resolve coherent biological patches and single targets in the horizontal, rising seafloor gas plumes, and scattering layer distributions tightly coupled to measured sub‐mesoscale features such as strong vertical oxygen gradients.

In Situ Cross-Linked Collagen-Based Biological Patch Integrating Anti-Infection and Anti-Calcification Properties.

Acellular dermal matrix (ADM) can be used as collagen-based biological patches for regeneration and repair of soft tissues in vivo. However, the problems of calcification and infection during treatment with patches can lead to premature patch failure and even to a severely increased risk of recurrence. In this study, first, porcine ADM (pADM) grafted with vinyl underwent an in situ cross-linking reaction in the presence of an initiator, while quaternary ammonium groups were introduced into the pADM during the cross-linking process to obtain MA-DMC-pADM, which is a biological patch with anti-infection and anti-calcification properties. The results of physicochemical property tests of the material showed that the pADM after cross-linking had better physical and mechanical properties. Importantly, antibacterial and anti-calcification experiments showed that MA-DMC-pADM had a good antibacterial and anti-calcification effect. Therefore, the MA-DMC-pADM biological patch facilitates their longer-lasting effectiveness, allowing pADM to be used in a wider range of applications.

Small intestinal submucosa-derived extracellular matrix as a heterotopic scaffold for cardiovascular applications.

Structural cardiac lesions are often surgically repaired using prosthetic patches, which can be biological or synthetic. In the current clinical scenario, biological patches derived from the decellularization of a xenogeneic scaffold are gaining more interest as they maintain the natural architecture of the extracellular matrix (ECM) after the removal of the native cells and remnants. Once implanted in the host, these patches can induce tissue regeneration and repair, encouraging angiogenesis, migration, proliferation, and host cell differentiation. Lastly, decellularized xenogeneic patches undergo cell repopulation, thus reducing host immuno-mediated response against the graft and preventing device failure. Porcine small intestinal submucosa (pSIS) showed such properties in alternative clinical scenarios. Specifically, the US FDA approved its use in humans for urogenital procedures such as hernia repair, cystoplasties, ureteral reconstructions, stress incontinence, Peyronie's disease, penile chordee, and even urethral reconstruction for hypospadias and strictures. In addition, it has also been successfully used for skeletal muscle tissue reconstruction in young patients. However, for cardiovascular applications, the results are controversial. In this study, we aimed to validate our decellularization protocol for SIS, which is based on the use of Tergitol 15S 9, by comparing it to our previous and efficient method (Triton X 100), which is not more available in the market. For both treatments, we evaluated the preservation of the ECM ultrastructure, biomechanical features, biocompatibility, and final bioinductive capabilities. The overall analysis shows that the SIS tissue is macroscopically distinguishable into two regions, one smooth and one wrinkle, equivalent to the ultrastructure and biochemical and proteomic profile. Furthermore, Tergitol 15S 9 treatment does not modify tissue biomechanics, resulting in comparable to the native one and confirming the superior preservation of the collagen fibers. In summary, the present study showed that the SIS decellularized with Tergitol 15S 9 guarantees higher performances, compared to the Triton X 100 method, in all the explored fields and for both SIS regions: smooth and wrinkle.

Patch angioplasty during carotid endarterectomy using different materials has similar clinical outcomes

ObjectivePatch angioplasty during carotid endarterectomy (CEA) is commonly used to treat carotid artery stenosis. However, the choice of which patch to use remains a matter of debate. Autologous venous material has disadvantages such as wound-related problems at the harvest site and a prolonged intervention time. These limitations can be bypassed when synthetic or biological patches are used. Both materials have been associated with divergent advantages and disadvantages. Therefore, the aim of our study was to compare the long-term follow-up outcomes in patients who underwent CEA and closure with either a bovine pericardial patch (BPP) or polyester patch. MethodsA retrospective cohort study was conducted including all patients who underwent primary CEA and closure with a BPP or a polyester patch between January 2010 and December 2020 at our tertiary referral center. In 2015, the BPP was introduced as an alternative for polyester. The primary outcome was the occurrence of transient ischemic attack (TIA) or cerebrovascular accident (CVA) during follow-up and secondary outcomes included restenosis, reintervention, all-cause mortality, and patch infection. Cox proportional hazard models were used and hazard ratios with 95% confidence intervals were used to predict these outcomes. ResultsWe included 417 CEA patients; 254 patients (61%) received a BPP and 163 received (39%) a polyester patch. The mean age was 70.2 ± 8.7 years and 67% were male. The median follow-up time was 15 months (range, 12-27 months) for BPP and 42 months (range, 16-60 months) for polyester (P < .001). Postoperative hematoma (≤30 days) was significantly lower in the BPP cohort (2% BPP vs 6% polyester; P = .047). No other significant differences on short-term outcomes were found. Univariable Cox regression analyses showed no significant differences between the effect estimates of polyester and BPP on TIA or CVA (P = .106), restenosis (P = .211), reintervention (P = .549), or all-cause mortality (P = .158). No significant differences were found after adjusting for confounders in the multivariable analyses: TIA or CVA (P = .939), restenosis (P = .057), reintervention (P = .193) and all-cause mortality (P = .742). Three patients with a polyester patch had patch infection compared with none of the patients in the group who received a BPP. ConclusionsThis large retrospective study showed comparable safety and durability of both BPP and polyester suggesting that both patch types can be safely applied for CEA with patch angioplasty. Patch infection was rare and was absent in the BPP group.

Donor neo-atrial cuff construction after accidental lower lobe vein transection

BackgroundAn inadequate donor left atrial cuff is a rare technical issue after graft procurement for lung transplantation. With regard to the shortage of suitable donor organs for lung transplantation, these organs should be surgically reconstructed to avoid the loss of an organ and a futile intervention in the critically ill recipient.Case presentationWe report a case of a 62-year old patient who underwent bilateral sequential lung transplantation for chronic obstructive pulmonary disease. During isolated lung procurement, the right inferior pulmonary vein was circumferentially transsected and separated from the right superior pulmonary and middle lobe veins. Subsequently, a reconstruction of the left atrial cuff with an acellular biological patch was performed to complete the atrium anastomosis. The patient experienced an uneventful postoperative recovery and a follow-up ventilation/perfusion scan showed normal perfusion of the right lower lobe.ConclusionsThis case demonstrates that reconstruction of an inadequate left atrial cuff with a biological patch is feasible and allows for an adequate venous drainage and therefore normal transplant organ function.

Short and long term results of biological pericardial patches and prosthetic patches used for carotid endarterectomy with patch angioplasty: A retrospective bicentric study

Several patches are available on the market to perform carotid endarterectomy (CE) with angioplasty, including prosthetic and biological patches; among these, pericardial patches are relatively recent. In spite of the growing use of biological patches, few data are available in the literature comparing the results of these two types of patches. The aim of this study was to compare the short and long term results of bovine pericardium (BP) and prosthetic patches (PP) used for carotid endarterectomy.

Landscape Impacts on Ecosystem Service Values Using the Image Fusion Approach

The landscape is a complex mosaic of physical and biological patches with infrastructures, cultivable lands, protected ecosystems, water bodies, and many other landforms. Varying land-use changes are vulnerable to the world and need the mitigation and management of landforms to achieve sustainable development, which without proper oversight, may lead to habitat destruction, degradation, and fragmentation. In this study, we quantify the land-use and land-cover (LULC) changes using downscaled satellite imagery and assess their effects on ecosystem services (ES) and economic values in Ningxia Province, China. Various landscape metrics are derived to study the pattern and spatial configuration over 15 years (2005–2020), in which the landscapes are evolving. The impact of LULC change in various ES is analyzed using ecosystem service values (ESV) and validated with a sensitivity index. Finally, the level of urban sprawl (US) due to overpopulation is established using Renyi’s entropy. Using Landsat 8′s Operational Land Imager (OLI) datasets, we downscaled the MODIS data of 2005, 2010, 2015, and 2020 to prepare the LULC map through a rotation forest algorithm. Results demonstrate that water bodies, woodlands, and built-up landscapes increased in their spatial distribution over time and that there was a decrease in farmlands. Results further suggest that the connectivity and uniformity of the landscape pattern improved in the later period due to several plans formulated by the government with a slight improvement in landscape diversity. Overall ESV get improved, while LULC classes such as farmland and water bodies have decreased and increased ESV, respectively, and a sensitivity analysis is used to test the reliability of ESV on LULC classes. The level of US is 0.91 in terms of Renyi’s entropy, which reveals the presence of a dispersion of settlements in urban fringes. The simulated US for 2025 shows urbanization is more severe over a prolonged time and finally the impacts of the US in ESV are analyzed. Using an interdisciplinary approach, several recommendations are formulated to maintain the ESV despite rapid LULC changes and to achieve sustainable development globally.

Effect of new biological patch in repairing intrauterine adhesion and improving clinical pregnancy outcome in infertile women: study protocol for a randomized controlled trial

BackgroundEndometrial fibrosis caused by intrauterine adhesion (IUA) can lead to hypomenorrhea, amenorrhea, and even infertility and abortion. The postoperative recurrence rate of severe IUA remains high, giving rise to low pregnancy rates. An extracellular matrix (ECM) scaffold, a new biological material that can promote cell proliferation and differentiation at lesions, has been widely used in general surgery and neurosurgery. The present study applied ECM scaffolds in obstetrics and gynecology for the first time to improve endometrial fibrosis, repair severe IUA, and improve pregnancy outcomes for infertile patients.MethodsThis paper presents a prospective randomized single-blind controlled superiority study of infertile women aged ≤40 years with IUA. According to the scoring criteria for IUA established by the American Fertility Society, patients with moderate or severe IUA were randomized into two groups at a ratio of 1:1; patients in the experimental group were treated with an ECM scaffold (small intestinal submucosa [SIS]) + intrauterine balloon, while patients in the control group were treated with an intrauterine balloon only. A hysteroscopic examination of adhesion repair was performed again after 2 months of postoperative hormone replacement therapy. Endometrial tissue was sampled during the two operations, and immunohistochemistry was used to observe endometrial and microvascular proliferation. After thawing and resuscitation, a postoperative frozen embryo transfer was performed on the participants in both groups, and their endometrial thickness, intrauterine volume, endometrial vascularization flow index, endometrial flow index, and uterine artery blood flow resistance were evaluated by 3D ultrasonography. The rates of embryo implantation, clinical pregnancy, and early spontaneous abortion were observed.DiscussionThe ECM scaffold (SIS) + intrauterine balloon method was able to repair endometrial fibrosis and improve IUA. This new technique represents a novel treatment method for improving the pregnancy outcome of infertile patients with moderate/severe IUA.Trial registrationChinese Clinical Trial Register ChiCTR2100052027. Registered on October 14, 2021.