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Femoral head necrosis (FHN) is a serious complication after femoral neck fractures (FNF), often linked to sclerosis around screw paths. Our study aimed to uncover the proteomic and metabolomic underpinnings of FHN and sclerosis using integrated proteomics and metabolomics analyses. We identified differentially expressed proteins (DEPs) and metabolites (DEMs) among three groups: patients with FNF (Group A), sclerosis (Group B), and FHN (Group C). Using the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses, we examined the roles of these proteins and metabolites. Our findings highlight the significant differences across the groups, with 218 DEPs and 44 DEMs identified between the sclerosis and FNF groups, 247 DEPs and 31 DEMs between the FHN and sclerosis groups, and a stark 682 DEPs and 94 DEMs between the FHN and FNF groups. Activities related to carbonate dehydratase and hydrolase were similar in the FHN and sclerosis groups, whereas extracellular region and lysosome were prevalent in the FHN and FNF groups. Our study also emphasized the involvement of the PI3K-Akt pathway in sclerosis and FHN. Moreover, the key metabolic pathways were implicated in glycerophospholipid metabolism and retrograde endocannabinoid signaling. Using western blotting, we confirmed the pivotal role of specific genes/proteins such as ITGB5, TNXB, CA II, and CA III in sclerosis and acid phosphatase 5 and cathepsin K in FHN. This comprehensive analyses elucidates the molecular mechanisms behind sclerosis and FHN and suggests potential biomarkers and therapeutic targets, paving the way for improved treatment strategies. Further validation of the findings is necessary to strengthen the robustness and reliability of the results.
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Fraturas do Colo Femoral , Necrose da Cabeça do Fêmur , Metabolômica , Proteômica , Humanos , Proteômica/métodos , Fraturas do Colo Femoral/metabolismo , Fraturas do Colo Femoral/cirurgia , Fraturas do Colo Femoral/patologia , Metabolômica/métodos , Necrose da Cabeça do Fêmur/metabolismo , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/patologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Esclerose/metabolismoRESUMO
Aquatic products are gaining popularity due to their delicacy and high nutrient value. However, they are perishable, with a short shelf-life. Frozen storage is associated with adverse effects, leading to protein oxidation and degradation, thereby altering the protein's structural integrity and subsequently influencing the palatability of protein-based food products. To address these challenges, novel antifreeze peptides have gained significant attention. Antifreeze peptides are a class of small molecular weight proteins or protein hydrolysates that offer protection to organisms in frozen or sub-frozen environments. They offer distinct advantages over conventional commercial antifreeze agents and natural antifreeze proteins. This review provides an overview of the current state of research on antifreeze agents, elucidates their characteristics and mechanisms, and examines their applications in aquatic products. Furthermore, the article offers insights into the prospective development and application prospects of antifreeze peptides.
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Osteochondral allograft (OCA) transplantation involves grafting of natural hyaline cartilage and supporting subchondral bone into the cartilage defect area to restore its biomechanical and tissue structure. However, differences in biomechanical properties and donor-host matching may impair the integration of articular cartilage (AC). This study analyzed the biomechanical properties of the AC in different regions of different sites of the knee joint and provided a novel approach to OCA transplantation. Intact stifle joints from skeletally mature pigs were collected from a local abattoir less than 8 h after slaughter. OCAs were collected from different regions of the joints. The patella and the tibial plateau were divided into medial and lateral regions, while the trochlea and femoral condyle were divided into six regions. The OCAs were analyzed and compared for Young's modulus, the compressive modulus, and cartilage thickness. Young's modulus, cartilage thickness, and compressive modulus of OCA were significantly different in different regions of the joints. A negative correlation was observed between Young's modulus and the proportion of the subchondral bone (r = - 0.4241, P < 0.0001). Cartilage thickness was positively correlated with Young's modulus (r = 0.4473, P < 0.0001) and the compressive modulus (r = 0.3678, P < 0.0001). During OCA transplantation, OCAs should be transplanted in the same regions, or at the closest possible regions to maintain consistency of the biomechanical properties and cartilage thickness of the donor and recipient, to ensure smooth integration with the surrounding tissue. A 7 mm depth achieved a higher Young's modulus, and may represent the ideal length.
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Aloenxertos , Cartilagem Articular , Articulação do Joelho , Animais , Cartilagem Articular/fisiologia , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Fenômenos Biomecânicos , Suínos , Módulo de Elasticidade , Transplante Ósseo/métodosRESUMO
This article designs a new hierarchical distributed data-driven adaptive learning control algorithm to accomplish the leader-following tracking control objective for nonaffine nonlinear multiagent systems (MASs). The proposed hierarchical control structure is composed of a distributed observer and a decentralized data-driven adaptive learning controller. Considering that some followers cannot directly receive information from the leader, a distributed observer is designed to estimate the information of the leader. Based on this, a decentralized data-driven adaptive learning controller is further devised to enable the follower to track the estimated information of the leader, where the model parameter learning algorithm is developed to capture the dynamic characteristics of the original system. One advantage of the developed hierarchical control learning algorithm is that neither the leader's system model nor the follower's system model is needed. The other one is the elimination of the noncausal problem without the additional assumption. Simulation results exemplify the merits of the theoretical results by comparisons.
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OBJECTIVES: The current clinical pulse lavage technique for flushing fresh osteochondral allografts (OCAs) to remove immunogenic elements from the subchondral bone is ineffective. This study aimed to identify the optimal method for removing immunogenic elements from OCAs. METHODS: We examined five methods for the physical removal of immunogenic elements from OCAs from the femoral condyle of porcine knees. We distributed the OCAs randomly into the following seven groups: (1) control, (2) saline, (3) ultrasound, (4) vortex vibration (VV), (5) low-pulse lavage (LPL), (6) high-pulse lavage (HPL), and (7) high-speed centrifugation (HSC). OCAs were evaluated using weight measurement, micro-computed tomography (micro-CT), macroscopic and histological evaluation, DNA quantification, and chondrocyte activity testing. Additionally, the subchondral bone was zoned to assess the bone marrow and nucleated cell contents. One-way ANOVA and paired two-tailed Student's t-test are used for statistical analysis. RESULTS: Histological evaluation and DNA quantification showed no significant reduction in marrow elements compared to the control group after the OCAs were treated with saline, ultrasound, or VV treatments; however, there was a significant reduction in marrow elements after LPL, HPL, and HSC treatments. Furthermore, HSC more effectively reduced the marrow elements of OCAs in the middle and deep zones compared with LPL (p < 0.0001) and HPL (p < 0.0001). Macroscopic evaluation revealed a significant reduction in blood, lipid, and marrow elements in the subchondral bone after HSC. Micro-CT, histological analyses, and chondrocyte viability results showed that HSC did not damage the subchondral bone and cartilage; however, LPL and HPL may damage the subchondral bone. CONCLUSION: HSC may play an important role in decreasing immunogenicity and therefore potentially increasing the success of OCA transplantation.
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Cartilagem Articular , Fraturas Intra-Articulares , Animais , Suínos , Aloenxertos , Microtomografia por Raio-X , Transplante Homólogo , Cartilagem , DNA , Cartilagem Articular/cirurgiaRESUMO
Heart disease accounts for millions of deaths worldwide annually, representing a major public health concern. Large-scale heart disease screening can yield significant benefits both in terms of lives saved and economic costs. In this study, we introduce a novel algorithm that trains a patient-specific machine learning model, aligning with the real-world demands of extensive disease screening. Customization is achieved by concentrating on three key aspects: data processing, neural network architecture, and loss function formulation. Our approach integrates individual patient data to bolster model accuracy, ensuring dependable disease detection. We assessed our models using two prominent heart disease datasets: the Cleveland dataset and the UC Irvine (UCI) combination dataset. Our models showcased notable results, achieving accuracy and recall rates beyond 95 % for the Cleveland dataset and surpassing 97 % accuracy for the UCI dataset. Moreover, in terms of medical ethics and operability, our approach outperformed traditional, general-purpose machine learning algorithms. Our algorithm provides a powerful tool for large-scale disease screening and has the potential to save lives and reduce the economic burden of heart disease.
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Algoritmos , Cardiopatias , Humanos , Aprendizado de Máquina , Redes Neurais de Computação , Cardiopatias/diagnósticoRESUMO
PURPOSE: To evaluate the clinical characteristics and global trends in the surgical treatment of articular cartilage defects. METHODS: Studies in English published between January 1, 2001 and December 31, 2020 were retrieved from MEDLINE, WOS, INSPEC, SCIELO, KJD, and RSCI on the "Web of Science." Patient data were extracted, including age, sex, defect location and laterality, duration of follow-up and symptoms, and body mass index (BMI). Data were further stratified according to the surgical method, lesion location, procedural type and geographical area, and time period. A comparative analysis was performed. RESULTS: Overall, 443 studies involving 26,854 patients (mean age, 35.25 years; men, 60.5%) were included. The mean lesion size and patient BMI were 3.51 cm2 and 25.61 kg/m2, respectively. Cartilage defects at the knees, talus, and hips affected 20,850 (77.64%), 3,983 (14.83%), and 1,425 (5.31%) patients, respectively. The numbers of patients who underwent autologous chondrocyte implantation, arthroscopic debridement/chondroplasty, osteochondral allograft (OCA), osteochondral autologous transplantation, and microfracture were 7,114 (26.49%), 5,056 (18.83%), 3,942 (14.68%), 3,766 (14.02%), and 2,835 (10.56%), respectively. European patients were the most numerous and youngest. North American patients had the largest defects. The number of patients increased from 305 in 2001 to 3,017 in 2020. In the last 5 years, the frequency of OCAs showed a greatly increasing trend. CONCLUSION: Clinical characteristics and global trends in the surgical treatment of articular cartilage defects were revealed. The choice of operation should be based on the patient characteristics and defect location, size, and shape, as well as the patient's preference.
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OBJECTIVES: Drain tube management after liver transplant is controversial. A new peritoneal drainage management protocol was developed to validate clinical characteristics, such as drain characteristics, postoperative complications, duration of postoperative hospital stay, changes in albumin levels, and 30-day readmission rates. MATERIALS AND METHODS: Data from 183 consecutive patients who underwent deceased donor liver transplant at our institution between January 2019 and June 2022 were retrospectively analyzed. A new drain management protocol was implemented on August 1, 2021, which included early removal of the drain tube when the serum albumin level was >3 g/dL and nonchylous fluid drainage was <200 mL/day. RESULTS: When we compared the traditional and new drain management protocol groups (n = 131 vs n = 52), the new management protocol group showed a decrease in the median duration of intraperitoneal drainage. In addition, the median length of postoperative hospital stay decreased from 33 to 27 days and serum albumin levels returned to normal faster at postoperative 3 weeks. No significant differences were found in postoperative hemorrhage, hematoma, hydrops abdominis, infections, biliary complications, orin the rate ofreinterventions and 30-day rehospitalizations. CONCLUSIONS: The new management protocol was associated with fewer postoperative hospital days and faster recovery than traditional management. Our findings may aid in the development of new drain policy recommendations based on preexisting risk factors.
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Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Doadores Vivos , Drenagem/efeitos adversos , Drenagem/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Tempo de Internação , Albumina Sérica , HospitaisRESUMO
Background: Osteochondral allograft transplantation (OCA) treats symptomatic focal cartilage defects with satisfactory clinical results. Purpose: To comprehensively analyze the characteristics and clinical outcomes of OCA for treating articular cartilage defects. Study Design: Systematic review; Level of evidence, 4. Methods: We searched Embase, PubMed, Cochrane Database, and Web of Science for studies published between January 1, 2001, and December 31, 2020, on OCA for treating articular cartilage defects. Publication information, patient data, osteochondral allograft storage details, and clinical outcomes were extracted to conduct a comprehensive summative analysis. Results: In total, 105 studies involving 5952 patients were included. The annual reported number of patients treated with OCA increased from 69 in 2001 to 1065 in 2020, peaking at 1504 cases in 2018. Most studies (90.1%) were performed in the United States. The mean age at surgery was 34.2 years, and 60.8% of patients were male and had a mean body mass index of 26.7 kg/m2. The mean lesion area was 5.05 cm2, the mean follow-up duration was 54.39 months, the mean graft size was 6.85 cm2, and the number of grafts per patient was 54.7. The failure rate after OCA was 18.8%, and 83.1% of patients reported satisfactory results. Allograft survival rates at 2, 5, 10, 15, 20, and 25 years were 94%, 87.9%, 80%, 73%, 55%, and 59.4%, respectively. OCA was mainly performed on the knee (88.9%). The most common diagnosis in the knee was osteochondritis dissecans (37.9%), and the most common defect location was the medial femoral condyle (52%). The most common concomitant procedures were high tibial osteotomy (28.4%) and meniscal allograft transplantation (24.7%). After OCA failure, 54.7% of patients underwent revision with primary total knee arthroplasty. Conclusion: The annual reported number of patients who underwent OCA showed a significant upward trend, especially from 2016 to 2020. Patients receiving OCA were predominantly young male adults with a high body mass index. OCA was more established for knee cartilage than an injury at other sites, and its best indication was osteochondritis dissecans. This analysis demonstrated satisfactory long-term postoperative outcomes.
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In recent years, the optimization of straw-rotting formulations for cultivating edible mushrooms and the management of the resulting spent mushroom substrate have emerged as new challenges. This study aimed to investigate the composting of spent mushroom substrate produced from mushroom cultivation with various straw additions, under conditions where chicken manure was also used. Parameters measured during the composting process included temperature, pH, electrical conductivity (EC), germination index (GI), moisture, and total nitrogen content. Additionally, changes in nutrient content within the compost piles before and after composting were determined, and the variations in bacterial and fungal communities across different treatments before and after composting were analyzed using 16S rRNA and ITS sequencing. The results indicated that the spent mushroom substrate produced by adding 20% straw during mushroom cultivation was more suitable for composting treatment. The findings suggest that incorporating an appropriate amount of straw in mushroom cultivation can facilitate subsequent composting of spent mushroom substrate, providing an effective strategy for both environmental protection and cost reduction.
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This study investigated the effects of different concentrations of biological maturity agents on the composting process of Auricularia heimuer residue by adding them to the composting process. By measuring the changes in physical and chemical indicators and microbial diversity during composting, the results showed that the addition of biological maturity agents had a certain promoting effect on compost temperature, humidity, pH, seed germination index, and vitality index. Appropriate composting days can promote the accumulation of ammonium nitrogen. The carbon content of humin and E4/E6 of treatments A, B, and E were significantly higher than those of the initial treatment. D0.CK treatment had the most types of resistance genes and the most abundant resistance genes. As composting progresses, the abundance of 13 resistance genes decreased. Adding high concentrations of biological maturity agents can activate the defense mechanism during the composting process, greatly ensuring the safety of fungi residue as a fertilizer.
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Liver and kidney failure can lead to extensive accumulation of toxic metabolites in the blood and tissues, such as bilirubin, blood ammonia, endotoxins, cytokines, creatinine, uric acid, and urea, which aggravate the progression of the disease. Hemoperfusion can effectively adsorb and remove toxins from the blood and treat liver and kidney failure. However, the adsorption efficiency and safety of traditional hemoperfusion adsorbents are not ideal. Thus, it is urgent to develop adsorbents with good blood compatibility, as well as high adsorption and strong selective capacities, to fulfill the clinical needs. In recent years, new hemoperfusion adsorbents with improved adsorption performance and good blood compatibility have been developed. This review classifies and summarizes the recent research progress in hemoperfusion adsorbents for common blood toxins (bilirubin, blood ammonia, endotoxins, cytokines, creatinine, uric acid, and urea) produced by liver and kidney failure. The composition and structure of various toxin adsorbents, toxin adsorption performance, biocompatibility, blood safety, and the adsorption mechanisms of toxins are discussed. Based on a summary of recent studies, feasible strategies have been explored for designing and preparing hemoperfusion adsorbents to fulfill future development requirements. The trends and clinical application prospects of various toxin adsorbents are also discussed.
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PURPOSE: Conventional cannulated screws (CS) are the main treatment method for femoral neck fractures (FNF). However, the rate of femoral head necrosis remains high after FNF treatment. The study aimed to compare the biomechanical features of different internal fixation materials for the treatment of Pauwel type III FNF to explore new strategies for clinical management. METHODS: A new material was prepared by applying casting, freeze drying and sintering process. The independently developed calcium magnesium silicate ceramic powder and hydrogel solution were evenly mixed to obtain a high-viscosity bio-ink, and a bioceramic nail (BN) with high mechanical strength and high fracture toughness was successfully prepared. Four internal fixations were developed to establish the Pauwel type III FNF and healed fracture finite element models: A, three CSs; B, three BNs; C, two BNs and one CS; D, one BN and two CSs. Von Mises stress and displacement of the implants and femur were observed. RESULTS: The measured Mg content in ceramic powder was 2.08 wt%. The spectral data confirmed that the ceramic powder has high crystallinity, which coincides with the wollastonite-2 M (PDF# 27-0088). The maximum von Mises stresses for the four models were concentrated in the lower part of the fracture surface, at 318.42 Mpa, 103.52 MPa, 121.16 MPa, and 144.06 MPa in models A, B, C, and D, respectively. Moreover, the maximum Von-mises stresses of the implants of the four models were concentrated near the fracture end at 243.65 MPa (A) and 58.02 MPa (B), 102.18 MPa (C), and 144.06 MPa (D). The maximum displacements of the four models were 5.36 mm (A), 3.41 mm (B), 3.60 mm (C), and 3.71 mm (D). The displacements of the three models with BNs were similar and smaller than that of the triple CS fracture model. In the fracture healing models with and without three CSs, the greatest stress concentration was scattered among the lowest screw tail, femoral calcar region, and lateral femur shaft. The displacement and stress distributions in both models are generally consistent. The stress distribution and displacement of the three healed femoral models with BNs were essentially identical to the healing models with three CSs. The maximum von Mises stresses were 65.94 MPa (B), 64.61 MPa (C), and 66.99 MPa (D) while the maximum displacements of the three healed femoral models were 2.49 mm (B), 2.56 mm (C), and 2.49 mm (D), respectively. CONCLUSIONS: Bioceramic nails offer greater advantages than conventional canulated screws after femoral neck fractures. However, the combination of bioceramic nails and CSs is more clinically realistic; replacing all internal fixations with bioceramic nails after the healing of femoral neck fractures can solve the problem of sclerosis formation around CSs and improve bone reconstruction by their bioactivity.
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Pinos Ortopédicos , Parafusos Ósseos , Fraturas do Colo Femoral , Esclerose , Esclerose/prevenção & controle , Fraturas do Colo Femoral/cirurgia , Fraturas do Colo Femoral/terapia , Análise de Elementos FinitosRESUMO
BACKGROUND: Our previous studies have demonstrated the mechanical effect of sclerosis around screw paths on the healing of femoral neck fractures (FNF) after internal fixation. Furthermore, we discussed the possibility of using bioceramic nails (BNs) to prevent sclerosis. However, all these studies were conducted under static conditions as the patient was standing on one leg, while the effect of the stress generated during movement is unknown. The purpose of this study was to evaluate the stress and displacement under dynamic stress loading conditions. METHODS: Two types of internal fixation, namely cannulated screws and bioceramic nails, were utilized in conjunction with various finite element models of the femur. These models included the femoral neck fracture healing model, the femoral neck fracture model, and the sclerosis around screws model. The resulting stress and displacement were analyzed by applying the contact forces associated with the most demanding activities during gait, including walking, standing, and knee bending. The present study establishes a comprehensive framework for investigating the biomechanical properties of internal fixation devices in the context of femoral fractures. RESULTS: The stress at the top of the femoral head in the sclerotic model was increased by roughly 15 MPa during the knee bend and walking phases and by about 30 MPa during the standing phase compared to the healing model. The area of high stress at the top of the femoral head was increased during the sclerotic model's walking and standing phases. Additionally, the stress distribution throughout the dynamic gait cycle was comparable before and after the removal of internal fixations following the healing of the FNF. The overall stress distribution of the entire fractured femoral model was lower and more evenly distributed in all combinations of internal fixation. Furthermore, the internal fixation stress concentration was lower when more BNs were used. In the fractured model with three cannulated screws (CSs), however, the majority of the stress was concentrated around the ends of the fractures.The maximal stress in the healing model with one CS and two BNs was the highest at all stages of gait over three combinations of internal fixation, and the stress was mainly carried by CS. CONCLUSIONS: The presence of sclerosis around screw paths increases the risk of femoral head necrosis. Removal of CS has little effect on the mechanics of the femur after healing of the FNF. BNs have several advantages over conventional CSs after FNF. Replacing all internal fixations with BNs after the healing of FNF may solve the problem of sclerosis formation around CSs to improve bone reconstruction owing to their bioactivity.
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Fraturas do Colo Femoral , Titânio , Humanos , Análise de Elementos Finitos , Unhas , Esclerose , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Fenômenos BiomecânicosRESUMO
Donor-derived infection (DDI) associated with Scedosporium spp is extremely rare, and results in a very poor prognosis. The present study reports a probable DDI due to Scedosporium boydii (S. boydii) from a donor with neuropsychiatric systemic lupus erythematosus. Two recipients developed Scedosporiosis after kidney transplantation from the same donor. Recipient 1 died of central nervous system infection due to S. boydii based on the clinical presentations, and the positive metagenomic next-generation sequencing (mNGS) and culture results for the cerebrospinal fluid. The other recipient with urinary tract obstruction due to S. boydii, which was identified through the positive culture and mNGS results of the removed stents, was successfully treated by stent replacement and voriconazole administration. Undiagnosed disseminated donor infection and the transmission of S. boydii should be given attention, particularly when the donor and recipients have primary immunodeficiency disease. The screening of donors and recipients for S. boydii using mNGS may be helpful in guiding antifungal prophylaxis and treatment recipients, due to its higher sensitivity and shorter diagnostic time relative to other traditional techniques.
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Infecções Fúngicas Invasivas , Transplante de Rim , Lúpus Eritematoso Sistêmico , Humanos , Transplante de Rim/efeitos adversos , Voriconazol/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológicoRESUMO
Natural polymer hydrogels are widely used in various aspects of biomedical engineering, such as wound repair, owing to their abundance and biosafety. However, the low strength and the lack of function restricted their development and application scope. Herein, we fabricated novel multifunctional chitin/PEGDE-tannic acid (CPT) hydrogels through chemical- and physical-crosslinking strategies, using chitin as the base material, polyethylene glycol diglycidyl ether (PEGDE) and tannic acid (TA) as crosslinking agents, and 90 % ethanol as the regenerative bath. CPT hydrogels maintained a stable three-dimensional porous structure with suitable water contents and excellent biocompatibility. The mechanical properties of hydrogels were greatly improved (tensile stress up to 5.43 ± 1.14 MPa). Moreover, CPT hydrogels had good antibacterial, antioxidant, and hemostatic activities and could substantially promote wound healing in a rat model of full-thickness skin defect by regulating inflammatory responses and promoting collagen deposition and blood vessel formation. Therefore, this work provides a useful strategy to fabricate novel multifunctional CPT hydrogels with excellent mechanical, antibacterial, antioxidant, hemostatic, and biocompatible properties. CPT hydrogels could be promising candidates for wound healing.
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Hemostáticos , Ratos , Animais , Hemostáticos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Hidrogéis/farmacologia , Hidrogéis/química , Cicatrização/fisiologia , Antibacterianos/farmacologia , Antibacterianos/química , Quitina/farmacologiaRESUMO
Infections caused by bacteria have long constituted a major threat to human health and the economy. Therefore, there is an urgent need to design broad-spectrum antibacterial materials possessing good biocompatibility to treat such infections. Herein, inspired by the good biocompatibility of chitin and antibacterial properties of imidazolium salts, a polysaccharide-based material, imidazolium salt chitin (IMSC), was homogeneously prepared using a facile method with epichlorohydrin as a chemical crosslinker to combine chitin with imidazole to enhance Staphylococcus aureus (S. aureus)-infected wound healing. The characteristics, antimicrobial properties, and biosafety of IMSC were evaluated. The results demonstrated successful grafting of imidazole onto chitin. Furthermore, IMSC exhibited good water solubility, broad-spectrum antimicrobial activity, hemocompatibility, and biocompatibility. Moreover, IMSC enabled complete healing of S. aureus-infected wound in Sprague-Dawley rats within 15 days of application, thus demonstrating that IMSC could reduce wound inflammation and remarkably accelerate wound healing owing to its efficient antibacterial activity and ability to promote collagen deposition in and around the wound area. Therefore, this study provides a promising and potential therapeutic strategy for infected wound healing by synthesizing a water-soluble and broad-spectrum antimicrobial material exhibiting good biocompatibility.
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Anti-Infecciosos , Infecção dos Ferimentos , Ratos , Animais , Humanos , Staphylococcus aureus , Ratos Sprague-Dawley , Escherichia coli , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Quitina/farmacologia , Quitina/uso terapêutico , Quitina/química , Cloreto de Sódio , Água/química , Infecção dos Ferimentos/tratamento farmacológicoRESUMO
The problem of the model-free adaptive resilient control (MFARC) for nonlinear cyber-physical systems (CPSs) suffered from aperiodic jamming attacks is investigated in this article. First, the MFARC framework subject to aperiodic jamming attacks is established, and an intermediate variable method is introduced to avoid using the unavailable time-varying parameter and further eliminate an extra assumption on the sign limit of it. Then, a MFARC scheme is devised to track the desired output, where the problem of the tracking control can be transformed into solving a feasibility problem, and the controller parameters can be obtained with the aid of the linear matrix inequality technique. What is more, a novel attack compensation mechanism is developed in the MFARC scheme to mitigate the impact of aperiodic jamming attacks. In the last, an example is provided to verify the effectiveness of the devised MFARC scheme.
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This article addresses the distributed model-free adaptive control (DMFAC) problem for learning nonlinear multiagent systems (MASs) subjected to denial-of-service (DoS) attacks. An improved dynamic linearization method is proposed to obtain an equivalent linear data model for learning systems. To alleviate the influence of DoS attacks, an attack compensation mechanism is developed. Based on the equivalent linear data model and the attack compensation mechanism, a novel learning-based DMFAC algorithm is developed to resist DoS attacks, which provides a unified framework to solve the leaderless consensus control, the leader-following consensus control, and the containment control problems. Finally, simulation examples are shown to illustrate the effectiveness of the developed DMFAC algorithm.
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Background: This study aimed to explore the clinical study of clopidogrel combined with Huoxue Tongluo prescription in improving transient ischemic attack (TIA) and the effect on MMP-9, Hcy, and CRP. Methods: A total of 84 patients with TIA admitted to our hospital from December 2019 to February 2021 were selected. The patients were divided into the control group (42 cases: not treated with Huoxue Tongluo prescription) and study group (42 cases: treatment with Huoxue Tongluo prescription). The clinical efficacy, adverse reactions, the levels of blood pressure and lipid, blood rheology and cerebral hemodynamics, neurological function-related indicators, MMP-9, Hcy, and CRP of the two groups were compared. Results: The total effective rate in the study group was higher than the control group. Compared with before treatment, the levels of SBP and DBP in both groups decreased memorably after treatment, and those in the study group decreased more particularly than the control group. The levels of LDL, HDL, TC, and TG in the study group were significantly better than those in the control group. The plasma viscosity, whole blood high shear viscosity, whole blood low shear viscosity, and hematocrit of patients in the study group were lower than those in the control group, and the maximum blood flow velocity, minimum blood flow velocity, average blood flow velocity, and average blood flow were higher than those in the control group. The levels of NSE, MBP, and S100ß in the study group were more memorably lower than those in the control group. After treatment, the levels of MMP-9, Hcy, and CRP in the study group were significantly lower than those in the control group. There was no obvious difference in the incidence of adverse reactions between the study group and control group. Conclusion: Clopidogrel combined with Huoxue Tongluo prescription can significantly improve the therapeutic effect and reduce the levels of MMP-9, Hcy, and CRP in patients with TIA.