ABSTRACT
Glycolysis has a major role in cancer progression and can affect the tumor immune microenvironment, while its specific role in lung adenocarcinoma (LUAD) remains poorly studied. We obtained publicly available data from The Cancer Genome Atlas and Gene Expression Omnibus databases and used R software to analyze the specific role of glycolysis in LUAD. The Single Sample Gene Set Enrichment Analysis (ssGSEA) indicated a correlation between glycolysis and unfavorable clinical outcome, as well as a repression effect on the immunotherapy response of LUAD patients. Pathway enrichment analysis revealed a significant enrichment of MYC targets, epithelial-mesenchymal transition (EMT), hypoxia, G2M checkpoint, and mTORC1 signaling pathways in patients with higher activity of glycolysis. Immune infiltration analysis showed a higher infiltration of M0 and M1 macrophages in patients with elevated activity of glycolysis. Moreover, we developed a prognosis model based on six glycolysis-related genes, including DLGAP5, TOP2A, KIF20A, OIP5, HJURP, and ANLN. Both the training and validation cohorts demonstrated the high efficiency of prognostic prediction in this model, which identified that patients with high risk may have a poorer prognosis and lower sensitivity to immunotherapy. Additionally, we also found that Th2 cell infiltration may predict poorer survival and resistance to immunotherapy. The study indicated that glycolysis is significantly associated with poor prognosis in patients with LUAD and immunotherapy resistance, which might be partly dependent on the Th2 cell infiltration. Additionally, the signature comprised of six genes related to glycolysis showed promising predictive value for LUAD prognosis.
Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Humans , Th2 Cells , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/therapy , Glycolysis/genetics , Immunotherapy , Lung Neoplasms/genetics , Lung Neoplasms/therapy , Tumor Microenvironment/geneticsABSTRACT
A hydroponic method was conducted to test whether Spathiphyllum kochii is tolerant to multiple HMs as well as to evaluate whether sodium silicate promotes plant growth and alleviates HM stress mainly by assessing biomass, HM accumulation characteristics and antioxidant enzyme activities (AEAs). Three soil extractions from an uncontaminated soil, a comparable lightly HM-contaminated soil (EnSE), and a comparable heavily HM-contaminated soil (ExSE) with or without 1 mM sodium silicate supplementation were used. S. kochii showed no obvious symptoms when cultured in EnSE and ExSE, indicating that it was a multi-HM-tolerant species. The biomass and photosynthesis followed the order: UnSE > EnSE > ExSE, but the opposite order was found for HM concentration, AEAs, and malondialdehyde content. Silicate had no effects on the growth and HM bioaccumulation characteristics of S. kochii cultured in UnSE but exhibited a novel role in decreasing HM uptake by 13.61-41.51% in EnSE and ExSE, respectively, corresponding upregulated AEAs, and reduced malondialdehyde contents, resulting in increased biomass and alleviating HM stress. The activities of peroxidase and superoxide dismutase were upregulated by an increase in soil extraction HM concentration and further upregulated by silicate supplementation, indicating that they were important mechanisms alleviating HM stress in S. kochii.
Phytoremediation is an economical and environmentally friendly technology for the alleviation of heavy metal (HM)-contaminated soil. Improving bioremediation efficiency is crucial for this kind of technology. Many studies have shown that silicon plays a novel role in plant growth and adversity responses, but studies in the field of phytoremediation are limited. In addition, phytoremediation plant species are usually hyperaccumulators or may be tolerant crops, commercial crops, or wild species from mining areas, and the use of landscape species in phytoremediation is limited. This is the first report on the effects of silicate on the multi-HM bioaccumulation characteristics of a garden plant (Spathiphyllum kochii) cultured in uncontaminated and HM-contaminated soil extractions. This study will broaden phytoremediation species screening and enrich our understanding of the mechanisms by which Si supports the bioremediation of HM-contaminated environments.HIGHLIGHTSS. kochii was a multi-heavy metal-tolerant species.Silicon played a novel role in reducing heavy metal concentrations by 1440% and 1442% in shoots and roots, respectively.Silicon upregulated antioxidant enzyme activities to alleviate heavy metal stress in plants.
Subject(s)
Metals, Heavy , Soil Pollutants , Metals, Heavy/analysis , Soil , Biodegradation, Environmental , Soil Pollutants/analysis , Silicates , Dietary SupplementsABSTRACT
A hydroponic method was performed to explore the effects of sulfate supply on the growth, manganese (Mn) accumulation efficiency and Mn stress alleviation mechanisms of Polygonum lapathifolium Linn. Three Mn concentrations (1, 8 and 16 mmol L-1, representing low (Mn1), medium (Mn8) and high (Mn16) concentrations, respectively) were used. Three sulfate (S) levels (0, 200, and 400 µmol L-1, abbreviated as S0, S200 and S400, respectively) were applied for each Mn concentration. (1) The average biomass (g plant-1) of P. lapathifolium was ordered as Mn8 (6.36) > Mn1 (5.25) > Mn16 (4.16). Under Mn16 treatment, S addition increased (P < 0.05) biomass by 29.96% (S200) and 53.07% (S400) compared to that S0. The changes in the net photosynthetic rate and mean daily increase in biomass were generally consistent with the changes in biomass. (2) Mn accumulation efficiency (g plant-1) was ordered as Mn8 (99.66) > Mn16 (58.33) > Mn1 (27.38); and S addition increased (p < 0.05) plant Mn accumulation and Mn transport, especially under Mn16 treatment. (3) In general, antioxidant enzyme activities (AEAs) and malondialdehyde (MDA) in plant leaves were ordered in Mn16 > Mn8 > Mn1. Sulfate addition decreased (P < 0.05) AEAs and MDA under Mn16 treatment, while the changes were minor under Mn1 and Mn8 treatments. (4) Amino acid concentrations generally increased with increasing Mn concentration and S level. In summary, the medium Mn treatment promoted plant growth and Mn bioaccumulation; sulfate, especially at 400 µmol L-1 S, can effectively promote plant growth and Mn accumulation efficiency. The most suitable bioremediation strategy was Mn16 with 400 µmol L-1 S.
Subject(s)
Biodegradation, Environmental , Manganese/toxicity , Polygonum/physiology , Sulfates/metabolism , Antioxidants/metabolism , Biomass , Hydroponics , Malondialdehyde/metabolism , Manganese/metabolism , Plant Development , Plant Leaves/metabolism , Plants/metabolism , Polygonum/growth & development , Soil Pollutants/analysis , Sulfates/analysisABSTRACT
Background: Decreased handgrip strength (HGS) and activities of daily living (ADL) disability are common in aging populations. No studies have evaluated the bidirectional associations between HGS and ADL disability. This study aimed to explore the bidirectional effects of HGS and ADL disability. Methods: This study analyzed data from two waves (2011 and 2015) of China Health and Retirement Longitudinal Study (CHARLS). Low HGS is defined by the Asian Working Group for Sarcopenia criteria. Meanwhile, disability was assessed by ADLs scale. The prospective bidirectional association between HGS and ADL disability was examined using binary logistic regression. Subgroup analysis were performed according to age and gender. Results: A total of 4,902 and 5,243 participants were included in the Stage I and Stage II analyses, respectively. On the one hand, low HGS was significantly associated with subsequent ADL disability. The odds ratio (OR) value of developing BADL disability and IADL disability were 1.60 (95% confidence interval (CI): 1.23-2.08) and 1.40 (95% CI: 1.15-1.70), respectively, in participants with low HGS. On the other hand, baseline ADL disability was associated with an increased risk of developing low HGS. The OR value of developing low HGS were 1.84 (95% CI: 1.34-2.51) and 1.46 (95% CI: 1.19-1.79) for participants with BADL disability and participants with IADL disability, respectively. Lastly, the strength of the bidirectional associations varied among subgroups. Conclusions: A significant bidirectional associations were identified between HGS and ADL disability. Interventions should be developed to prevent the development or progression of both low HGS and ADL disability.
Subject(s)
Activities of Daily Living , Hand Strength , Humans , Prospective Studies , Longitudinal Studies , RetirementABSTRACT
BACKGROUND: Evidence regarding the association between anemia and sarcopenia in the elderly population is limited and controversial. The purpose of this study was to investigate the association between anemia and sarcopenia in Chinese elderly. METHODS: The cross-sectional study used the third wave of data from the China Longitudinal Study of Health and Retirement (CHARLS). Participants were classified as sarcopenic versus non-sarcopenic according to the guidelines developed by the Asian Working Group for Sarcopenia (AWGS) 2019. Meanwhile, participants were defined for anemia using World Health Organization criteria. Logistic regression models were conducted to assess the association between anemia and sarcopenia. Odds ratios (OR) were reported to indicate the strength of the association. RESULTS: A total of 5016 participants were included in the cross-sectional analysis. The overall prevalence of sarcopenia in this population was 18.3 %. After adjusting for all potential risk factors, anemia and sarcopenia were independently associated (OR = 1.43, 95 % CI 1.15-1.77, P = 0.001). In terms of subgroups, the association of anemia with sarcopenia was also significant in people over 71 years of age (OR = 1.93, 95 % CI 1.40-2.66, P < 0.001), women (OR = 1.48, 95 % CI 1.09-2,02, P = 0.012), rural residents (OR = 1.56, 95 % CI 1.24-1.97, P < 0.001), as well as in people with low education (OR = 1.50, 95 % CI 1.20-1.89, P < 0.001). CONCLUSION: Anemia is an independent risk factor for sarcopenia among elderly Chinese population.
Subject(s)
Anemia , Sarcopenia , Aged , Female , Humans , Anemia/epidemiology , China/epidemiology , Cross-Sectional Studies , East Asian People , Longitudinal Studies , Prevalence , Sarcopenia/epidemiologyABSTRACT
Objective: This meta-analysis aimed to investigate the effect of bariatric surgery on CIMT in people with obesity. Methods: PubMed, Web of Science, Embase, and the Cochrane Library were searched for observational studies assessing the effect of bariatric surgery on CIMT from inception to August 2022. Mean difference (MD) and 95% confidence intervals were calculated to assess CIMT. Results: A total of 23 studies, including 1,349 participants, were eligible to participate in this meta-analysis. The results revealed that CIMT was significantly decreased at 6 months, 12 months, and more than 18 months after bariatric surgery compared with baseline (6 months: MD = 0.09; P < 0.01; 12 months: MD = 0.12; P < 0.01; more than 18 months: MD = 0.14; P = 0.02). Meanwhile, laparoscopic Roux-en-Y gastric bypass (LRYGB) seemed to be more effective than laparoscopic sleeve gastrectomy (LSG) in lowering CIMT in terms of the type of surgery (LSG: MD = 0.11; P < 0.01; LRYGB: MD = 0.14; P < 0.01). Lastly, the benefits of bariatric surgery on CIMT was independent of gender (Male: MD = 0.06; P = 0.04; Female: MD = 0.08; P = 0.03). Conclusions: Bariatric surgery is consistently effective in reducing CIMT in people with obesity.
ABSTRACT
OBJECTIVE: Bariatric surgery increases the risk of postoperative gallstone formation. Many studies have proposed ursodeoxycholic acid (UDCA) as a preventive agent for postoperative gallstone formation. This study aimed to investigate the effect of UDCA on gallstone formation after bariatric surgery in patients without preoperative gallstones. METHODS: PubMed, the Web of Science, the Cochrane Library, and EBSCO were searched for articles assessing the effect of UDCA on gallstone formation after bariatric surgery. The outcome was the incidence of postoperative gallstones. Odds ratios were used to assess dichotomous variables, and random-effects models were used for statistical analyses. RESULTS: A total of 18 studies including 4,827 participants met the inclusion criteria. The statistical results showed that the incidence of gallstones in the UDCA group was significantly lower than in the control group. Furthermore, the occurrence of symptomatic gallstones and cholecystectomy was significantly reduced. CONCLUSIONS: In patients without preoperative gallstones, UDCA can effectively prevent the formation of gallstones after bariatric surgery. In addition, UDCA can significantly reduce the occurrence of symptomatic gallstones and the risk of postoperative cholecystectomy. Doses of 500 to 600 mg/d can be used as a measure to prevent postoperative gallstone formation.
Subject(s)
Bariatric Surgery , Gallstones , Obesity, Morbid , Bariatric Surgery/adverse effects , Bariatric Surgery/methods , Gallstones/epidemiology , Gallstones/etiology , Gallstones/prevention & control , Humans , Incidence , Obesity, Morbid/surgery , Postoperative Period , Ursodeoxycholic Acid/therapeutic useABSTRACT
Brain electroencephalography (EEG), the complex, weak, multivariate, nonlinear, and nonstationary time series, has been recently widely applied in neurocognitive disorder diagnoses and brain-machine interface developments. With its specific features, unlabeled EEG is not well addressed by conventional unsupervised time-series learning methods. In this article, we handle the problem of unlabeled EEG time-series clustering and propose a novel EEG clustering algorithm, that we call mwcEEGc. The idea is to map the EEG clustering to the maximum-weight clique (MWC) searching in an improved Fréchet similarity-weighted EEG graph. The mwcEEGc considers the weights of both vertices and edges in the constructed EEG graph and clusters EEG based on their similarity weights instead of calculating the cluster centroids. To the best of our knowledge, it is the first attempt to cluster unlabeled EEG trials using MWC searching. The mwcEEGc achieves high-quality clusters with respect to intracluster compactness as well as intercluster scatter. We demonstrate the superiority of mwcEEGc over ten state-of-the-art unsupervised learning/clustering approaches by conducting detailed experimentations with the standard clustering validity criteria on 14 real-world brain EEG datasets. We also present that mwcEEGc satisfies the theoretical properties of clustering, such as richness, consistency, and order independence.
Subject(s)
Brain-Computer Interfaces , Electroencephalography , Algorithms , Brain/diagnostic imaging , Cluster Analysis , Time FactorsABSTRACT
Forward osmosis (FO) membranes have the advantages of low energy consumption, high water recovery rate, and low membrane pollution trend, and they have been widely studied in many fields. However, the internal concentration polarization (ICP) caused by the accumulation of solutes in the porous support layer will reduce permeation efficiency, which is currently unavoidable. In this paper, we doped Graphene oxide (GO) nanoparticles (50~150 nm) to a polyamide (PA) active layer and/or polysulfone (PSF) support layer, investigating the influence of GO on the morphology and properties of thin-film composite forward osmosis (TFC-FO) membranes. The results show that under the optimal doping amount, doping GO to the PA active layer and PSF support layer, respectively, is conducive to the formation of dense and uniform nano-scale water channels perpendicular to the membrane surface possessing a high salt rejection rate and low reverse solute flux without sacrificing high water flux. Moreover, the water channels formed by doping GO to the active layer possess preferable properties, which significantly improves the salt rejection and water permeability of the membrane, with a salt rejection rate higher than 99% and a water flux of 54.85 L·m-2·h-1 while the pure PSF-PA membrane water flux is 12.94 L·m-2·h-1. GO-doping modification is promising for improving the performance and structure of TFC-FO membranes.
ABSTRACT
Well ordered mesoporous diopside (OMD) nanobiomaterial was synthesized by a sol-gel process. The in vitro bioactivity of the OMD was evaluated by investigating the apatite-forming ability in simulated body fluid (SBF), and the hemostatic activity of the OMD was determined by measuring the activated partial thromboplastin time (APTT) and prothrombin time (PT) in vitro. The results suggested that the OMD exhibited excellent in vitro bioactivity, with surface apatite formation for OMD exceeding that of non-mesoporous diopside (n-MD) at 7 days. Moreover, the OMD with high surface area possessed good hemostatic property because it could absorb a large number of water from the blood. In conclusion, the prepared OMD had excellent bioactivity and hemostatic activity, which can not only be applied as bone repair biomaterial for bone regeneration, but also as hemostatic agent for surgery hemostasis.
Subject(s)
Biocompatible Materials , Nanostructures , Silicic Acid/chemistry , Hemostasis/drug effects , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , X-Ray DiffractionABSTRACT
Mesoporous silica xerogels with various amount of calcium (0, 5, 10 and 15%, named m-SXC0, m-SXC5, m-SXC10 and m-SXC15, respectively) were synthesized by template sol-gel methods, and cell responses to m-SXCs were studied using murine pre-osteoblast MC3T3-E1 in vitro. The results showed that cell morphology was not affected by m-SXCs indicating good biocompatibility. Furthermore, cell proliferation ratio on the m-SXCs increased over time, among which m-SXC10 was highest. NO production obviously rose with the increase of Ca content in m-SXCs. ALP activity and PGE(2) level on m-SXC5 significantly improved compared with m-SXC0 while decreased with the increase of Ca content for m-SXC10 and m-SXC15. No obvious discrepancy on osteopontin mRNA expressions was observed among m-SXCs. The collagen I and osteocalcin mRNA expression on m-SXC5 were up-regulated, while decreased on m-SXC15 evidently. The phosphorylation level of ERK 1/2 for the m-SXC10 was highest after 7 days. In conclusion, calcium in m-SXCs plays an important role in osteoblast activity, which indicates mesoporous silica xerogel containing appropriate calcium could stimulate osteoblast proliferation, differentiation, gene expression via the activation of ERK 1/2 signaling pathway, and shows great prospects in bone regeneration field using as a drug controlled release filler.
Subject(s)
Calcium/metabolism , Osteoblasts/metabolism , Silicon Dioxide/metabolism , Silicone Gels , Animals , Animals, Newborn , Cell Differentiation/genetics , Cell Line , Cell Proliferation , In Vitro Techniques , Materials Testing , Mice , Osteoblasts/cytology , Osteocalcin/genetics , Osteocalcin/metabolism , Osteogenesis , Osteopontin/genetics , Osteopontin/metabolism , Signal Transduction/genetics , Skull/cytologyABSTRACT
Phosphate (P) fertilization is a commonly used agronomic practice. However, research on bioremediation is very limited. This study's principal objective was to evaluate the role of P in the growth and heavy metals (HMs) accumulation of Polygonum pubescens Blume cultured in Mn-contaminated soil. To this end, the effects of sodium dihydrogen phosphate (SDP) and single superphosphate (SSP) on the growth, Mn bioremediation efficiency, organ HMs, and physiological parameters related to antioxidant stress of P. pubescens were examined. The results showed that both SDP and SSP increased soil pH and available P but decreased available HMs. Phosphate significantly (P < 0.05) promoted P. pubescens height and biomass. Average height increased by 36.1% and 32.6% with SDP and SSP, respectively, with corresponding biomass increases of 71.8% and 135%. Phosphate significantly (P < 0.05) reduced Mn concentrations, especially in leaves, where the values decreased by >50.0% for DSP and SSP. Total Mn significantly (P < 0.05) decreased with DSP amendment but significantly (P < 0.05) increased by 38.5% with SSP (200 mg kg-1) through an increase in biomass. Phosphate significantly (P < 0.05) decreased all organ HM concentrations and translocation, indicating that less HM stress occurred with P amendment. The changes in reactive oxygen species, antioxidants and non-antioxidant materials further supported these results. Pearson correlation analysis revealed negative relationships between soil available P and HMs, indicating a novel role of P in HM passivation. The uncommonly high Ca concentrations in leaves suggested that Ca plays a vital role in promoting growth and alleviating HM stress in P. pubescens, which warrants further study.
Subject(s)
Biodegradation, Environmental , Manganese/metabolism , Soil Pollutants/metabolism , Biomass , Manganese/analysis , Metals, Heavy/analysis , Phosphates/analysis , Plant Leaves/chemistry , Polygonum/growth & development , Soil , Soil Pollutants/analysisABSTRACT
Improvement of energy density is an urgent task for developing advanced supercapacitors. In this paper, aqueous supercapacitors with high voltage of 1.8 V and energy density of 29.1 W h kg(-1) were fabricated based on carbon nanofibers (CNFs) and Na2SO4 electrolyte. The CNFs with radially grown graphene sheets (GSs) and small average diameter down to 11 nm were prepared by electrospinning and carbonization in NH3. The radially grown GSs contain between 1 and a few atomic layers with their edges exposed on the surface. The CNFs are doped with nitrogen and oxygen with different concentrations depending on the carbonizing temperature. The supercapacitors exhibit excellent cycling performance with the capacity retention over 93.7% after 5000 charging-discharging cycles. The unique structure, possessing radially grown GSs, small diameter, and heteroatom doping of the CNFs, and application of neutral electrolyte account for the high voltage and energy density of the present supercapacitors. The present supercapacitors are of high promise for practical application due to the high energy density and the advantages of neutral electrolyte including low cost, safety, low corrosivity, and convenient assembly in air.
Subject(s)
Carbon/chemistry , Graphite/chemistry , Nanofibers/chemistry , Ammonia/chemistry , Electrolytes/chemistry , Nitrogen/chemistry , Oxygen/chemistry , Temperature , Water/chemistryABSTRACT
The regenerative treatment of large osseous defects remains a formidable challenge in orthopedic surgery today. In the present study, we have synthesized biodegradable calcium/magnesium-doped silica-based scaffolds with hierarchically macro/mesoporous structure (CMMS), and incorporated recombinant human bone morphogenetic protein-2 (rhBMP-2) into the scaffolds to obtain a hybrid system for osteogenic factor delivery in the functional repair of bone defects. The developed CMMS/rhBMP-2 scaffolds presented interconnected porous network, macropores (200-500 µm) and mesopores (5.7 nm), as well as good bioactivity and biocompatibility and proper degradation rate. Combined with the capacity to deliver ions and growth factors, the CMMS/rhBMP-2 scaffolds significantly promoted the in vitro osteogenic differentiation of bone marrow stromal cells (bMSCs), as evidenced by the enhanced expression of Runx-2, osteopontin, osteocalcin and bone sialoprotein, and induced the ectopic bone formation in the thigh muscle pouches of mice. We further assessed the in vivo effects of CMMS/rhBMP-2 scaffolds in a rabbit femur cavity defect model by using synchrotron radiation-based µCT (SRµCT) imaging and histological analysis, indicating that the CMMS/rhBMP-2 scaffolds resulted in more bone regeneration compared to that observed with the CMMS scaffolds without rhBMP-2. Moreover, scaffolds with or without rhBMP-2 underwent gradual resorption and replacement with bone and almost disappeared at 12 weeks, while the dense CMMS/rhBMP-2 material showed slower degradation rate and promoted the least extensive neo-bone formation. This study suggested that the hybrid CMMS/rhBMP-2 scaffolds system demonstrates promise for bone regeneration in clinical case of large bone defects.
Subject(s)
Bone Morphogenetic Protein 2/chemistry , Calcium , Magnesium , Silicon Dioxide , Synchrotrons , Tomography, X-Ray Computed/methods , Animals , Biocompatible Materials , Bone Marrow Cells/cytology , Bone and Bones/cytology , Cell Differentiation , Cell Proliferation , Humans , Male , Mice , Mice, Inbred C57BL , Rabbits , Recombinant Proteins/chemistry , Stromal Cells/cytology , X-Ray DiffractionABSTRACT
Efficacious hemostatic agents have significant potential for use in rapid exsanguinating hemorrhage control by emergency medical technician or military medic nowadays. Unfortunately, the topical hemostats currently available in market still have various disadvantages. In this study, a series of macroporous chitosan coated mesoporous silica xerogel beads (CSSX) with good biocompatibility were developed. They consisted of mesoporous silica xerogel cores and chitosan layers with macroporous structure by using modified sol-gel process and PEG molecular imprinting technique. The textural properties of the CSSX beads were optimized by in vitro and in vivo evaluation for promoting blood clotting and the results indicated that the prepared CSSX beads can significantly accelerate the contact activation pathway of coagulation cascade and produce desirable hemostasis, with the best efficiency from the CSSX prepared with 2% chitosan and 5% PEG. Furthermore, these CSSX beads were observed to create no exothermic reaction and the subsequential tissue thermal injury by histological examination, and exhibited no obvious cytotoxicity even after 7 days. The results of the present study forward CSSX bead as a safe hemostatic system and present a platform for further optimization studies of materials with enhanced hemostatic capabilities for specific injury types.
Subject(s)
Chitosan/chemistry , Coated Materials, Biocompatible , Gels , Hemorrhage/drug therapy , Hemostatics/chemistry , Molecular Imprinting , Silicon Dioxide/chemistry , Animals , Cell Line , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/therapeutic use , Femoral Artery/pathology , Gels/chemistry , Gels/therapeutic use , Hemostasis , Humans , Materials Testing , Mice , Microscopy, Electron, Scanning , Porosity , RabbitsABSTRACT
Effective hemorrhage control becomes increasingly significant in today's military and civilian trauma, and current available local hemostatic agents have been reported to have various drawbacks and side effects. Herein in this study, a silver exchanged calcium doped ordered mesoporous silica sphere (AgCaMSS) with good degradability and antibacterial properties was developed for hemorrhage control. The well-ordered and symmetry hexagonal AgCaMSS with pore size of 3.2 nm, BET surface area of 919 m(2)/g and pore volume of 0.74 m(3)/g was prepared by one-step based catalyzed self-assembly and subsequent ion-exchange procedures. The degradation behaviors in Tris-HCl solution indicated that the addition of calcium and silver facilitated the dissolution and the weight loss of the prepared AgCaMSS could attain more than 40% after 42 days. The results obtained demonstrated that the optimal AgCaMSS formulation could significantly promote the blood clotting, activate the intrinsic pathway of coagulation cascade, induce platelet adherence. Consequently, effective hemostasis with low exothermic effects was achieved and the mortalities in femoral artery and liver injury models were reduced. The antibacterial experiment using broth culture method revealed that the prepared AgCaMSS had better antibacterial activities against Escherichia coli and Staphylococcus aureus. Based on these results, it can be concluded that the AgCaMSS developed here would be a promising material platform for designing hemostats in more extensive clinical application.
Subject(s)
Bacterial Infections/prevention & control , Hemorrhage/prevention & control , Hemostatics/administration & dosage , Hemostatics/chemistry , Silver/chemistry , Silver/pharmacology , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bacterial Infections/complications , Drug Carriers/chemistry , Hemorrhage/complications , Male , Materials Testing , Microspheres , Porosity , Rabbits , Treatment OutcomeABSTRACT
A well-defined mesoporous structure of wollastonite with high specific surface area was synthesized using surfactant P123 (triblock copolymer) as template, and its composite scaffolds with poly(epsilon-caprolactone) (PCL) were fabricated by a simple method of solvent casting-particulate leaching. The measurements of the water contact angles suggest that the incorporation of either mesoporous wollastonite (m-WS) or conventional wollastonite (c-WS) into PCL could improve the hydrophilicity of the composites, and the former was more effective than the later. The bioactivity of the composite scaffold was evaluated by soaking the scaffolds in a simulated body fluid (SBF) and the results show that the m-WS/PCL composite (m-WPC) scaffolds can induce a dense and continuous layer of apatite after soaking for 1 week, as compared with the scattered and discrete apatite particles on the c-WS/PCL composite (c-WPC) scaffolds. The m-WPC had a significantly enhanced apatite-forming bioactivity compared with the c-WPC owing to the high specific surface area and pore volume of m-WS. In addition, attachment and proliferation of MG(63) cells on m-WPC scaffolds were significantly higher than that of c-WPC, revealing that m-WPC scaffolds had excellent biocompatibility. Such improved properties of m-WPC should be helpful for developing new biomaterials and may have potential use in hard tissue repair.