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Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea and colitis. It is recognized as one of the most significant hospital-acquired infections. Although CDI can develop severe complications and spores of Clostridioides difficile can be transmitted by the fecal-oral route, CDI is occasionally overlooked in clinical settings. Thus, it is necessary to monitor high CDI risk groups, particularly those undergoing antibiotic treatment, to prevent complications and spread. We developed and validated a deep learning-based model to predict the occurrence of CDI within 28 days after starting antibiotic treatment using longitudinal electronic health records. For each patient, timelines of vital signs and laboratory tests with a 35-day monitoring period and a patient information vector consisting of age, sex, comorbidities, and medications were constructed. Our model achieved the prediction performance with an area under the receiver operating characteristic curve of 0.952 (95% CI: 0.932-0.973) in internal validation and 0.972 (95% CI: 0.968-0.975) in external validation. Platelet count and body temperature emerged as the most important features. The risk score, the output value of the model, exhibited a consistent increase in the CDI group, while the risk score in the non-CDI group either maintained its initial value or decreased. Using our CDI prediction model, high-risk patients requiring symptom monitoring can be identified. This could help reduce the underdiagnosis of CDI, thereby decreasing transmission and preventing complications.
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In recent years, the implementation of energy-harvesting technology in medical equipment has attracted significant interest owing to its potential for self-powered and smart healthcare systems. Herein, the integration of a triboelectric nanogenerator (TENG) is proposed into an inhaler for energy-harvesting and smart inhalation monitoring. For this initially, barium sodium niobium oxide (Ba2NaNb5O15) microparticles (BNNO MPs) are synthesized via a facile solid-state synthesis process. The BNNO MPs with ferroelectricity and high dielectric constant are incorporated into polydimethylsiloxane (PDMS) polymer to make BNNO/PDMS composite films (CFs) for TENG fabrication. The fabricated TENG is operated in a contact-separation mode, and its electrical output performance is compared to establish the optimal BNNO MPs concentration. Furthermore, multi-wall carbon nanotubes (MWCNTs), a conductive filler material, are used to enhance the electrical conductivity of the CFs, thereby improving the electrical output performance of the TENG. The robustness/durability of the proposed BNNO-MWCNTs/PDMS CF-based TENG are investigated. The proposed TENG device is demonstrated to harvest electrical energy from mechanical motions via regular human activities and power portable electronics. The TENG is integrated into the inhaler casing to count the number of sprays remaining in the canister, send the notification to a smartphone via Bluetooth, and harvest energy.
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INTRODUCTION: Angiotensin receptor blockers are widely used antihypertensive drugs in South Korea. In 2021, the Korea Ministry of Food and Drug Safety acknowledged the need for national compensation for a drug-induced liver injury (DILI) after azilsartan use. However, little is known regarding the association between angiotensin receptor blockers and DILI. OBJECTIVE: We conducted a retrospective cohort study in incident users of angiotensin receptor blockers from a common data model database (1 January, 2017-31 December, 2021) to compare the risk of DILI among specific angiotensin receptor blockers against valsartan. METHODS: Patients were assigned to treatment groups at cohort entry based on prescribed angiotensin receptor blockers. Drug-induced liver injury was operationally defined using the International DILI Expert Working Group criteria. Cox regression analyses were conducted to derive hazard ratios and the inverse probability of treatment weighting method was applied. All analyses were performed using R. RESULTS: In total, 229,881 angiotensin receptor blocker users from 20 university hospitals were included. Crude DILI incidence ranged from 15.6 to 82.8 per 1000 person-years in treatment groups, most were cholestatic and of mild severity. Overall, the risk of DILI was significantly lower in olmesartan users than in valsartan users (hazard ratio: 0.73 [95% confidence interval 0.55-0.96]). In monotherapy patients, the risk was significantly higher in azilsartan users than in valsartan users (hazard ratio: 6.55 [95% confidence interval 5.28-8.12]). CONCLUSIONS: We found a significantly higher risk of suspected DILI in patients receiving azilsartan monotherapy compared with valsartan monotherapy. Our findings emphasize the utility of real-world evidence in advancing our understanding of adverse drug reactions in clinical practice.
Subject(s)
Angiotensin Receptor Antagonists , Chemical and Drug Induced Liver Injury , Electronic Health Records , Humans , Republic of Korea/epidemiology , Retrospective Studies , Chemical and Drug Induced Liver Injury/epidemiology , Chemical and Drug Induced Liver Injury/etiology , Male , Female , Angiotensin Receptor Antagonists/adverse effects , Middle Aged , Electronic Health Records/statistics & numerical data , Aged , Cohort Studies , Antihypertensive Agents/adverse effects , Incidence , Adult , Valsartan/adverse effects , Risk Factors , Benzimidazoles/adverse effectsABSTRACT
Neuropathic pain (NP) is a debilitating condition stemming from damage to the somatosensory system frequently caused by nerve injuries or lesions. While existing treatments are widely employed, they often lead to side effects and lack specificity. This study aimed to alleviate NP by developing an innovative sustained-release thermosensitive hydrogel system. The system incorporates hyaluronic acid (HA)/Pluronic F127 injectable hydrogel and bupivacaine (Bup, B) in combination with poly(lactic-co-glycolic acid; PLGA)/modified magnesium hydroxide (MH)/luteolin (Lut; PML) microspheres (PML@B/Gel). The PML@B/Gel was designed for localized and prolonged co-delivery of Bup and Lut as an anesthetic and anti-inflammatory agent, respectively. Our studies demonstrated that PML@B/Gel had exceptional biocompatibility, anti-inflammatory, and antioxidant properties. In addition, it exhibited efficient pain relief in in vitro cellular assays. Moreover, this functional hydrogel showed substantial sustained drug release while diminishing microglial activation. Consequently, it effectively mitigated mechanical allodynia and thermal hyperalgesia in in vivo rat models of chronic constriction injury (CCI). Based on our research findings, PML@B/Gel emerges as a promising therapeutic approach for the protracted treatment of NP.
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The undesirable dendrite growth induced by non-planar zinc (Zn) deposition and low Coulombic efficiency resulting from severe side reactions have been long-standing challenges for metallic Zn anodes and substantially impede the practical application of rechargeable aqueous Zn metal batteries (ZMBs). Herein, we present a strategy for achieving a high-rate and long-cycle-life Zn metal anode by patterning Zn foil surfaces and endowing a Zn-Indium (Zn-In) interface in the microchannels. The accumulation of electrons in the microchannel and the zincophilicity of the Zn-In interface promote preferential heteroepitaxial Zn deposition in the microchannel region and enhance the tolerance of the electrode at high current densities. Meanwhile, electron aggregation accelerates the dissolution of non-(002) plane Zn atoms on the array surface, thereby directing the subsequent homoepitaxial Zn deposition on the array surface. Consequently, the planar dendrite-free Zn deposition and long-term cycling stability are achieved (5,050 h at 10.0 mA cm-2 and 27,000 cycles at 20.0 mA cm-2). Furthermore, a Zn/I2 full cell assembled by pairing with such an anode can maintain good stability for 3,500 cycles at 5.0 C, demonstrating the application potential of the as-prepared ZnIn anode for high-performance aqueous ZMBs.
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The skin is the largest organ and a crucial barrier for protection against various intrinsic and extrinsic factors. As we age, the skin's components become more vulnerable to damage, forming wrinkles. Among different procedures, hyaluronic acid-based hydrogel has been extensively utilized for skin regeneration and reducing wrinkles. However, it has limitations like low retention and weak mechanical properties. In this study, we suggested the poly(l-lactic acid) (PLLA) microparticles containing alkaline magnesium hydroxide and nitric oxide-generating zinc oxide and rejuvenative hyaluronic acid (HA) hydrogels including these functional microparticles and asiaticoside, creating a novel delivery system for skin rejuvenation and regeneration. The fabricated rejuvenative hydrogels have exhibited enhanced biocompatibility, pH neutralization, reactive oxygen species scavenging, collagen biosynthesis, and angiogenesis capabilities in vitro and in vivo. Additionally, an excellent volume retention ability was demonstrated due to the numerous hydrogen bonds that formed between hyaluronic acid and asiaticoside. Overall, our advanced injectable hydrogel containing functional microparticles, with controlled release of bioactive molecules, has a significant potential for enhancing the regeneration and rejuvenation of the skin.
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Background/Aims: The impact of sedation on cardio-cerebrovascular (CCV) adverse events after esophagogastroduodenoscopy (EGD) in patients with gastric cancer (GC) is unclear. We investigated the incidence rate and impact of sedation on CCV adverse events after surveillance EGD in patients with GC. Methods: We performed a nationwide population-based cohort study using the Health Insurance Review and Assessment Service databases from January 1, 2018, to December 31, 2020. Using a propensity score-matched analysis, patients with GC were divided into two groups: sedative agent users and nonusers for surveillance EGD. We compared the occurrence of CCV adverse events within 14 days between the two groups. Results: Of the 103,463 patients with GC, newly diagnosed CCV adverse events occurred in 2.57% of patients within 14 days after surveillance EGD. Sedative agents were used in 41.3% of the patients during EGD. The incidence rates of CCV adverse events with and without sedation were 173.6/10,000 and 315.4/10,000, respectively. Between sedative agent users and nonusers based on propensity score matching (28,008 pairs), there were no significant differences in the occurrence of 14-day CCV, cardiac, cerebral, and other vascular adverse events (2.28% vs 2.22%, p=0.69; 1.44% vs 1.31%, p=0.23; 0.74% vs 0.84%, p=0.20; 0.10% vs 0.07%, p=0.25, respectively). Conclusions: Sedation during surveillance EGD was not associated with CCV adverse events in patients with GC. Therefore, the use of sedative agents may be considered in patients with GC during surveillance EGD without excessive concerns about CCV adverse events.
Subject(s)
Stomach Neoplasms , Humans , Stomach Neoplasms/epidemiology , Stomach Neoplasms/diagnosis , Cohort Studies , Endoscopy, Digestive System/adverse effects , Hypnotics and Sedatives/adverse effects , Incidence , Conscious Sedation/adverse effectsABSTRACT
Achieving satisfactory bone tissue regeneration in osteoporotic patients with ordinary biomaterials is challenging because of the decreased bone mineral density and aberrant bone microenvironment. In addressing this issue, a biomimetic scaffold (PMEH/SP), incorporating 4-hexylresorcinol (4HR), and substance P (SP) into the poly(lactic-go-glycolic acid) (PLGA) scaffold with magnesium hydroxide (M) and extracellular matrix (E) is introduced, enabling the consecutive release of bioactive agents. 4HR and SP induced the phosphorylation of p38 MAPK and ERK in human umbilical vein endothelial cells (HUVECs), thereby upregulating VEGF expression level. The migration and tube-forming ability of endothelial cells can be promoted by the scaffold, which accelerates the formation and maturation of the bone. Moreover, 4HR played a crucial role in the inhibition of osteoclastogenesis by interrupting the IκB/NF-κB signaling pathway and exhibiting SP, thereby enhancing the migration and angiogenesis of HUVECs. Based on such a synergistic effect, osteoporosis can be suppressed, and bone regeneration can be achieved by inhibiting the RANKL pathway in vitro and in vivo, which is a commonly known mechanism of bone physiology. Therefore, the study presents a promising approach for developing a multifunctional regenerative material for sophisticated osteoporotic bone regeneration.
Subject(s)
Bone Regeneration , Human Umbilical Vein Endothelial Cells , Osteoporosis , Polylactic Acid-Polyglycolic Acid Copolymer , Tissue Scaffolds , Bone Regeneration/drug effects , Humans , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Tissue Scaffolds/chemistry , Osteoporosis/drug therapy , Osteoporosis/metabolism , Animals , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Osteogenesis/drug effectsABSTRACT
As interest in skin aesthetics increases, treatments to suppress aging are increasing. Among them, a facelift is the most effective procedure for improving wrinkles. However, side effects including inflammatory reactions occur due to the limitations of the PDO thread itself used during the procedure. In this paper, to improve the function of PDO thread, inorganic particles such as magnesium hydroxide (MH) and zinc oxide (ZO) and a biologically active agent, asiaticoside, were coated on the surface of PDO thread using ultrasonic coating technology. The coated thread exhibited excellent biocompatibility, promoted collagen synthesis, reduced inflammation, and stimulated angiogenesis in vitro and in vivo. The multifunctional PDO thread has shown promising potential for skin regeneration without inducing fibrosis. Such a practical coating system and the developed multifunctional PDO thread suggest new possibilities for developing safer and more effective materials in cosmetic and regenerative medicine to prevent aging and improve skin aesthetics.
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BACKGROUND/AIMS: The number of endoscopic procedures and related adverse events is increasing. We investigated South Korean endoscopists' awareness and experience of endoscopic adverse events. MATERIALS AND METHODS: We used Google Forms to conduct an online questionnaire survey among South Korean endoscopists from December 11 to 29, 2020. The survey comprised 30 questions developed by members of the Quality Management Committee of the Korean Society of Gastrointestinal Endoscopy. RESULTS: In total, 475 endoscopists participated in the survey. Of these, 454 (95.6%) were board-certified gastroenterologists and 255 (53.7%) had >10 years of endoscopy experience. Most participants had experienced serious adverse events requiring hospitalization (80.4%, 382/475); however, only 100 (21.1%) were aware of programs for the prevention and management of adverse endoscopic events in their affiliated endoscopy centers. Most participants (98.5%, 468/475) agreed with the need for education on medical accidents for healthcare workers. Responses were inconsistent regarding the definition of adverse events formulated by the 2010 American Society for Gastrointestinal Endoscopy Workshop. Most participants were not aware of the minimal standard terminology (76.6%, 364/475) and had not used it when writing endoscopy reports (88.8%, 422/475). Responses were inconsistent regarding which events to record in endoscopy records. CONCLUSION: Further discussion on the nationwide adverse-event reporting system and education program for adverse events related to endoscopy is needed to ensure the safety of patients and endoscopists.
Subject(s)
Endoscopy, Gastrointestinal , Gastroenterologists , Humans , United States , Endoscopy, Gastrointestinal/methods , Surveys and Questionnaires , Republic of KoreaABSTRACT
Despite current developments in bone substitute technology for spinal fusion, there is a lack of adequate materials for bone regeneration in clinical applications. Recombinant human bone morphogenetic protein-2 (rhBMP-2) is commercially available, but a severe inflammatory response is a known side effect. Bone graft substitutes that enhance osteogenesis without adverse effects are needed. We developed a bioactive molecule-laden PLGA composite with multi-modulation for bone fusion. This bioresorbable composite scaffold was considered for bone tissue engineering. Among the main components, magnesium hydroxide (MH) aids in reduction of acute inflammation affecting disruption of new bone formation. Decellularized bone extracellular matrix (bECM) and demineralized bone matrix (DBM) composites were used for osteoconductive and osteoinductive activities. A bioactive molecule, polydeoxyribonucleotide (PDRN, PN), derived from trout was used for angiogenesis during bone regeneration. A nano-emulsion method that included Span 80 was used to fabricate bioactive PLGA-MH-bECM/DBM-PDRN (PME2/PN) composite to obtain a highly effective and safe scaffold. The synergistic effect provided by PME2/PN improved not only osteogenic and angiogenic gene expression for bone fusion but also improved immunosuppression and polarization of macrophages that were important for bone tissue repair, using a rat model of posterolateral spinal fusion (PLF). It thus had sufficient biocompatibility and bioactivity for spinal fusion.
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BACKGROUND/AIMS: This study aimed to evaluate the characteristics of endoscopic retrograde cholangiopancreatography (ERCP) or endoscopic ultrasonography (EUS)-related adverse events (AEs) that eventually lead to medical disputes or claims on medical professional liability. METHODS: Medical disputes for ERCP/EUS-related AEs filed in the Korea Medical Dispute Mediation and Arbitration Agency between April 2012 and August 2020 were evaluated using corresponding medical records. AEs were categorized into three sections: procedure-related, sedation-related, and safety-related AEs. RESULTS: Among a total of 34 cases, procedure-related AEs were 26 (76.5%; 12 duodenal perforations, 7 post-ERCP pancreatitis, 5 bleedings, 2 perforations combined with post-ERCP pancreatitis); sedation-related AEs were 5 (14.7%; 4 cardiac arrests, 1 desaturation), and safety-related AEs were 5 (8.8%; 1 follow-up loss for stent removal, 1 asphyxia, 1 fall). Regarding clinical outcomes, 20 (58.8%) were fatal and eventually succumbed to AEs. For the types of medical institutions, 21 cases (61.8%) occurred at tertiary or academic hospitals, and 13 (38.2%) occurred at community hospitals. CONCLUSION: The ERCP/EUS-related AEs filed in Korea Medical Dispute Mediation and Arbitration Agency showed distinct features: duodenal perforation was the most frequent AE, and clinical outcomes were fatal, resulting in at least more than permanent physical impairment.
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Background: Although beta-lactams are 1 of the major causative agents of severe cutaneous adverse reactions (SCAR), their epidemiology and clinical aspects have been poorly studied. This study aimed to investigate the characteristics of SCAR caused by beta-lactams in the Korean SCAR registry. Methods: We retrospectively analyzed beta-lactam-induced SCAR cases collected from 28 tertiary university hospitals in Korea between 2010 and 2015. The SCAR phenotypes included Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), SJS-TEN overlap, and drug reaction with eosinophilia and systemic symptoms (DRESS). Beta-lactams were classified according to their chemical structures: penicillins, cephalosporins, and carbapenems. The causative beta-lactams, clinical and laboratory features, treatments, and outcomes were evaluated. Results: Among the 275 antibiotic-induced SCAR cases, 170 patients developed SCAR induced by beta-lactams. Beta-lactam antibiotic-induced SCAR showed more frequent SJS/TEN compared to SCAR induced by non-beta-lactam antibiotics (SJS/TEN/SJS-TEN overlap/DRESS: 36.5/11.2/5.9/46.5% vs. 23.8/10.5/2.9/62.9%, P = 0.049). Cephalosporin was the most common culprit drug. Particularly, 91 and 79 patients presented with SJS/TEN and DRESS, respectively. The odds ratio (OR) for poor prognosis, such as sequelae and death, was significantly increased in subjects with SJS-TEN overlap and TEN and carbapenem as culprit drug in the multivariate analysis (OR, 35.61; P = 0.016, OR, 28.07; P = 0.006, OR 30.46; P = 0.027). Conclusion: Among antibiotic-induced SCAR, clinical features were different depending on whether the culprit drug was a beta-lactam antibiotic or SCAR type. The poor prognosis was related to SJS-TEN overlap, TEN type, and carbapenem as the culprit drug.
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Osteoporotic bone regeneration is a challenging process which involves the occurrence of sophisticated interactions. Although various polymeric scaffolds have been proposed for bone repair, research on osteoporotic bone regeneration remains practically limited. In particular, achieving satisfactory bone regeneration when using osteoporotic drugs is challenging including bisphosphonates. Here, a novel nitric oxide-releasing bioinspired scaffold with bioactive agents for the exquisite regeneration of osteoporotic bone is proposed. The bone-like biomimetic poly(lactic-co-glycolic acid) scaffold is first prepared in combination with organic/inorganic ECM and magnesium hydroxide as the base implant material. Nanoparticles containing bioactive agents of zinc oxide (ZO), alendronate, and BMP2 are incorporated to the biomimetic scaffold to impart multifunctionality such as anti-inflammation, angiogenesis, anti-osteoclastogenesis, and bone regeneration. Especially, nitric oxide (NO) generated from ZO stimulates the activity of cGMP and protein kinase G; in addition, ZO downregulates the RANKL/osteoprotegerin ratio by suppressing the Wnt/ß-catenin signaling pathway. The new bone is formed much better in the osteoporotic rat model than in the normal model through the regulation of bone homeostasis via the scaffold. These synergistic effects suggest that such a bioinspired scaffold could be a comprehensive way to regenerate exceptionally osteoporotic bones.
Subject(s)
Nitric Oxide , Osteoporosis , Rats , Animals , Nitric Oxide/pharmacology , Osteogenesis , Bone Regeneration , Bone and Bones/metabolism , Osteoporosis/drug therapy , Osteoporosis/metabolismABSTRACT
BACKGROUND: Efficient bowel preparation is essential for preventing colorectal cancer by improving endoscopic adenoma detection. Tablet for bowel preparation containing sulfate salts, OSTs (oral sulfate tablets), has been developed and it is gaining more popularity. However, its efficacy compared to standard preparation agent, PEG-AA (polyethylene glycol), has not been well discovered. We assessed the efficacy of PEG and OSTs using a real-time clinical data warehouse (CDW) model. METHODS: We performed a propensity score-matched (PSM) analysis of consecutive adult patients undergoing colonoscopy who received PEG-AA or OSTs prior to colonoscopy at a tertiary academic hospital. The endoscopic records of 992 adult patients were retrospectively analyzed. The clinical data warehouse collected data including bowel preparation, insertion time, observation time, and the detection of polyps and adenomas. Multivariate regression analysis was performed to reveal the factors associated with endoscopic outcomes. RESULTS: Among 992 patients included in the study, 770 and 222 patients received PEG-AA and OSTs, respectively. Among the propensity score-matched population (n = 1897), OSTs resulted in better bowel cleansing quality (8.16 vs 7.84, p = 0.014) and a higher adenoma detection rate (38.6% vs 27.1%, p = 0.003). Using PEG-AA, older age, inadequate bowel preparation (BBPS score < 6) and endoscopy by fellows were found to be factors associated with poor adenoma detection. In the elderly over 65 years of age, a significant difference in cleansing quality between the two groups (7.21 vs 8.19, p < 0.001) was found, but its impact on ADR was not prominent (49.5% vs 45.4%, p = 0.653). CONCLUSIONS: OSTs with simethicone achieved better endoscopic cleanliness, improving adenoma detection rate compared to the conventional PEG-AA protocol. The synergistic effect of both the convenience of taking tablets and the reduction of intraluminal bubble by adjunctive simethicone improves the clinical efficacy of colonoscopy.
Subject(s)
Adenoma , Polyethylene Glycols , Adult , Humans , Aged , Polyethylene Glycols/adverse effects , Simethicone , Cathartics/adverse effects , Sulfates , Propensity Score , Retrospective Studies , Colonoscopy/methods , Adenoma/diagnosis , Adenoma/chemically induced , TabletsABSTRACT
Background/Aims: Efficacy of proton pump inhibitors is limited in patients with nonerosive reflux disease (NERD). The aim of this study was to comparatively evaluate the efficacy and safety of esomeprazole with sodium bicarbonate and esomeprazole alone. Methods: This was a multicenter, randomized, double-blind, active-controlled, noninferiority comparative study. A total of 379 patients with NERD were randomly allocated to receive either Esoduoâ (esomeprazole 20 mg with sodium bicarbonate 800 mg) or Nexiumâ (esomeprazole 20 mg) once daily for 4 weeks from January 2019 to December 2019. The patients had a history of heartburn for at least 2 days in the week before randomization as well as in the last 3 months and no esophageal mucosal breaks on endoscopy. The primary endpoint was a complete cure of heartburn at week 4. The secondary and exploratory endpoints as well as the safety profiles were compared in the groups at weeks 2 and 4. Results: A total of 355 patients completed the study (180 in the Esoduoâ group and 175 in the Nexiumâ group). The proportions of patients without heartburn in the entire 4th week of treatment were not different between the two groups (33.33% in the Esoduoâ group and 35% in the Nexiumâ group, p=0.737). There were no significant differences in most of the secondary and exploratory endpoints as well as the safety profiles. Conclusions: Esoduoâ is as effective and safe as Nexiumâ for managing typical symptoms in patients with NERD (ClinicalTrial.gov identifier: NCT03928470).
Subject(s)
Esomeprazole , Gastroesophageal Reflux , Humans , Esomeprazole/adverse effects , Heartburn/drug therapy , Heartburn/etiology , Sodium Bicarbonate , Treatment Outcome , Gastroesophageal Reflux/drug therapy , Gastroesophageal Reflux/complications , Proton Pump Inhibitors , Double-Blind MethodABSTRACT
The development of a biodegradable vascular scaffold (BVS) for the treatment of cardiovascular diseases (CVDs) still requires some improvement. Among them, re-endothelialization and anti-inflammation are clinically important to restore vascular function. In this study, we proposed a coating system to deliver hydrophilic bioactive agents to BVS using nanoemulsion and drop-casting methods. The poly(L-lactide) (PLLA) scaffold containing magnesium hydroxide (MH) was coated on the surface with bioactive molecules such as polydeoxyribonucleotide (PDRN), L-arginine (Arg, R), and mesenchymal stem cell-derived extracellular vesicles (EVs). PDRN upregulates the expression of VEGF as one of the A2A receptor agonists; and Arg, synthesized into nitric oxide by intracellular eNOS, induces endothelialization. In particular, EVs, which are composed of a lipid bilayer and transfer bioactive materials such as protein and nucleic acid, regulate homeostasis in blood vessels. Such a bioactive agent coating system and its PLLA composite suggest a new platform for the treatment of cardiovascular dysfunction.
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BACKGROUND: Coronary artery disease is a cardiovascular disease with a high mortality and mortality rate in modern society. Vascular stent insertion to restore blood flow is essential to treat this disease. A fully biodegradable vascular scaffold (BVS) is a vascular poly (L-lactic acid) (PLLA) stent that is receiving growing interest as this is biodegradable in the body and does not require secondary removal surgery. However, acidic byproducts composed of PLLA produced during the biodegradation of the BVS can induce an inflammatory response. Magnesium hydroxide, a basic inorganic particle, neutralizes the acidic byproducts of PLLA. METHODS: In this study, we investigated using a BVS coated with everolimus and surface-modified magnesium hydroxide that suppresses smooth muscle cell proliferation and protects endothelial cells, respectively. The various characteristics of the functional stent were evaluated using in vitro and in vivo analyses. RESULTS: The BVS was successfully prepared with evenly coated everolimus and surface-modified magnesium hydroxide. A neutral pH value was maintained by magnesium hydroxide during degradation, and everolimus was released for one month. The coated BVS effectively inhibited protein adsorption and platelet adhesion, demonstrating excellent blood compatibility. In vitro analysis showed that BVS protects endothelial cells with magnesium hydroxide and selectively inhibits smooth muscle cell proliferation via everolimus treatment. The functional BVS was inserted into porcine coronary arteries for 28 days, and the results demonstrated that the restenosis and inflammation greatly decreased and re-endothelialization was enhanced as compared to others. CONCLUSIONS: This study provides new insights into the design of drug-incorporated BVS stent for coronary artery disease.