RESUMO
OBJECTIVES: To investigate whether a novel assessment of thrombus permeability obtained from perfusion computed tomography (CTP) can act as a more accurate predictor of clinical response to mechanical thrombectomy (MT) in acute ischemic stroke (AIS). MATERIALS AND METHODS: We performed a study including two cohorts of AIS patients who underwent MT admitted to a single-center between April 2018 and February 2022: a retrospective development cohort (n = 71) and a prospective independent validation cohort (n = 96). Thrombus permeability was determined in terms of entire thrombus time-attenuation curve (TAC) on CTP. Association between thrombus TAC distributions and histopathological results was analyzed in the development cohort. Logistic regression was used to assess the performance of the TAC for predicting 90-day modified Rankin Scale (mRS) score, and good outcome was defined as a mRS score of ≤ 2. Basic clinical characteristics was used to build a routine clinical model. A combined model gathered TAC and basic clinical characteristics was also developed. The performance of the three models is compared on the independent validation set. RESULTS: Two TAC distributions were observed-unimodal (uTAC) and linear (lTAC). TAC distributions achieved strong correlations (|r|= 0.627, p < 0.001) with histopathological results, in which uTAC associated with fibrin- and platelet-rich clot while lTAC associated with red blood cell-rich clot. The uTAC was independently associated with poor outcome (odds ratio, 0.08 [95% confidence interval (CI), 0.02-0.31]; p < 0.001). TAC distributions yielded an AUC of 0.78 (95% CI, 0.70-0.87) for predicting clinical outcome. When combined clinical characteristics, the performance was significantly improved (AUC, 0.85 [95% CI, 0.76-0.93]; p < 0.001) and higher than routine clinical model (AUC, 0.69 [95% CI, 0.59-0.83]; p < 0.001). CONCLUSIONS: Thrombus TAC on CTP were found to be a promising new imaging biomarker to predict the outcomes of MT in AIS. CLINICAL RELEVANCE STATEMENT: This study revealed that clot-based time attenuation curve based on admission perfusion CT could reflect the permeability and composition of thrombus and, also, provide valuable information to predict the clinical outcomes of mechanical thrombectomy in patients with acute ischemia stroke. KEY POINTS: ⢠Two time-attenuation curves distributions achieved strong correlations (|r|= 0.627, p < 0.001) with histopathological results. ⢠The unimodal time-attenuation curve was independently associated with poor outcome (odds ratio, 0.08 [0.02-0.31]; p < 0.001). ⢠The time-attenuation curve distributions yielded a higher performance for detecting clinical outcome than routine clinical model (AUC, 0.78 [0.70-0.87] vs 0.69 [0.59-0.83]; p < 0.001).
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Estudos Prospectivos , Trombectomia , Angiografia Cerebral/métodos , Isquemia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgiaRESUMO
Organic semiconductor single crystals (OSSCs) are ideal materials for studying the intrinsic properties of organic semiconductors (OSCs) and constructing high-performance organic field-effect transistors (OFETs). However, there is no general method to rapidly prepare thickness-controllable and uniform single crystals for various OSCs. Here, inspired by the recrystallization (a spontaneous morphological instability phenomenon) of polycrystalline films, a spatial confinement recrystallization (SCR) method is developed to rapidly (even at several second timescales) grow thickness-controllable and uniform OSSCs in a well-controlled way by applying longitudinal pressure to tailor the growth direction of grains in OSCs polycrystalline films. The relationship between growth parameters including the growth time, temperature, longitudinal pressure, and thickness is comprehensively investigated. Remarkably, this method is applicable for various OSCs including insoluble and soluble small molecules and polymers, and can realize the high-quality crystal array growth. The corresponding 50 dinaphtho[2,3-b:2â³,3â³-f]thieno[3,2-b]thiophene (DNTT) single crystals coplanar OFETs prepared by the same batch have the mobility of 4.1 ± 0.4 cm2 V-1 s-1 , showing excellent uniformity. The overall performance of the method is superior to the reported methods in term of growth rate, generality, thickness controllability, and uniformity, indicating its broad application prospects in organic electronic and optoelectronic devices.
RESUMO
Despite ongoing breakthroughs in novel anticancer therapies, chemotherapy remains a mainstream therapeutic modality in different types of cancer. Unfortunately, chemotherapy-related toxicity (CRT) often leads to dose limitation, and even results in treatment termination. Over the past few years, accumulating evidence has indicated that the gut microbiota is extensively engaged in various toxicities initiated by chemotherapeutic drugs, either directly or indirectly. The gut microbiota can now be targeted to reduce the toxicity of chemotherapy. In the current review, we summarized the clinical relationship between the gut microbiota and CRT, as well as the critical role of the gut microbiota in the occurrence and development of CRT. We then summarized the key mechanisms by which the gut microbiota modulates CRT. Furthermore, currently available strategies to mitigate CRT by targeting the gut microbiota were summarized and discussed. This review offers a novel perspective for the mitigation of diverse chemotherapy-associated toxic reactions in cancer patients and the future development of innovative drugs or functional supplements to alleviate CRT via targeting the gut microbiota.
RESUMO
OBJECTIVES: To develop a clot-based radiomics model using CT imaging radiomic features and machine learning to identify cardioembolic (CE) stroke before mechanical thrombectomy (MTB) in patients with acute ischemic stroke (AIS). MATERIALS AND METHODS: This retrospective four-center study consecutively included 403 patients with AIS who sequentially underwent CT and MTB between April 2016 and July 2021. These were grouped into training, testing, and external validation cohorts. Thrombus-extracted radiomic features and basic information were gathered to construct a machine learning model to predict CE stroke. The radiological characteristics and basic information were used to build a routine radiological model. A combined radiomics and radiological features model was also developed. The performances of all models were evaluated and compared in the validation cohort. A histological analysis helped further assess the proposed model in all patients. RESULTS: The radiomics model yielded an area under the curve (AUC) of 0.838 (95% confidence interval [CI], 0.771-0.891) for predicting CE stroke in the validation cohort, significantly higher than the radiological model (AUC, 0.713; 95% CI, 0.636-0.781; p = 0.007) but similar to the combined model (AUC, 0.855; 95% CI, 0.791-0.906; p = 0.14). The thrombus radiomic features achieved stronger correlations with red blood cells (|rmax|, 0.74 vs. 0.32) and fibrin and platelet (|rmax|, 0.68 vs. 0.18) than radiological characteristics. CONCLUSION: The proposed CT-based radiomics model could reliably predict CE stroke in AIS, performing better than the routine radiological method. KEY POINTS: ⢠Admission CT imaging could offer valuable information to identify the acute ischemic stroke source by radiomics analysis. ⢠The proposed CT imaging-based radiomics model yielded a higher area under the curve (0.838) than the routine radiological method (0.713; p = 0.007). ⢠Several radiomic features showed significantly stronger correlations with two main thrombus constituents (red blood cells, |rmax|, 0.74; fibrin and platelet, |rmax|, 0.68) than routine radiological characteristics.
Assuntos
AVC Embólico , AVC Isquêmico , Trombose , Humanos , AVC Isquêmico/diagnóstico por imagem , Estudos Retrospectivos , Trombose/complicações , Trombose/diagnóstico por imagem , Fibrina , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: We aimed to develop and validate a deep convolutional neural network (DCNN) model for preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) and its clinical outcomes using contrast-enhanced computed tomography (CECT) in a large population of candidates for surgery. METHODS: This retrospective study included 1116 patients with HCC who had undergone preoperative CECT and curative hepatectomy. Radiological (R), DCNN, and combined nomograms were constructed in a training cohort (n = 892) respectively based on clinicoradiological factors, DCNN probabilities, and all factors; the performance of each model was confirmed in a validation cohort (n = 244). Accuracy and the AUC to predict MVI were calculated. Disease-free survival (DFS) and overall survival (OS) after surgery were recorded. RESULTS: The proportion of MVI-positive patients was respectively 38.8% (346/892) and 35.7 % (87/244) in the training and validation cohorts. The AUCs of the R, DCNN, and combined nomograms were respectively 0.809, 0.929, and 0.940 in the training cohorts and 0.837, 0.865, and 0.897 in the validation cohort. The combined nomogram outperformed the R nomogram in the training (p < 0.001) and validation (p = 0.009) cohorts. There was a significant difference in DFS and OS between the R, DCNN, and combined nomogram-predicted groups with and without MVI (p < 0.001). CONCLUSIONS: The combined nomogram based on preoperative CECT performs well for preoperative prediction of MVI and outcome. KEY POINTS: ⢠A combined nomogram based on clinical information, preoperative CECT, and DCNN can predict MVI and clinical outcomes of patients with HCC. ⢠DCNN provides added diagnostic ability to predict MVI. ⢠The AUCs of the combined nomogram are 0.940 and 0.897 in the training and validation cohorts, respectively.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Invasividade Neoplásica , Redes Neurais de Computação , Nomogramas , Estudos RetrospectivosRESUMO
A semi-crystalline, shape memory polymer (SMP) is fabricated by free radical cross-linking, polymerization, and grafting in a blend of n-octadecyl acrylate and polybutadiene (PB). Poly(n-octadecyl acrylate) (PODA) is a side-chain crystalline polymer, which serves as the structure-fixing network counterbalancing the elastically deformed, cross-linked polymer network. At a constant 50/50 ratio of monomer and polymer the amount of free radical initiator, dicumyl peroxide (DCP) is varied from 1% to 5% w/w PB. From swelling measurements and calculation of the cross-link density it is determined that DCP produces greater than one cross-link per DCP molecule. It is found that lower cross-linking efficiency is favorable for higher shape fixity. This lower efficiency is found to produce a higher degree of crystallinity of the PODA in the 2-5% DCP samples, which is determined to be the main driver of higher shape fixity of the polymer. A SMP with >90% fixity and 100% recovery at uniaxial strains from 34-79% is achieved. This material should be useful for mold processing of shape memory articles. This approach provides a method to decouple the elastomeric and thermoplastic portions of a SMP to convert commodity elastomers into SMPs and tailor the shape memory response.
Assuntos
Materiais Inteligentes , Acrilatos , Butadienos , Elastômeros , Radicais Livres , PolimerizaçãoRESUMO
Vancomycin is a first-line treatment for invasive infections caused by multidrug-resistant gram-positive bacteria. However, vancomycin-induced nephrotoxicity is an increasing burden, particularly in patients with complex life-threatening conditions. Vancomycin-induced nephrotoxicity associated with clinically relevant exposure on the target site has not been well defined. This study aimed to acquire the concentration of vancomycin in the renal tubules and kidneys in humans using physiologically based pharmacokinetic (PBPK) modeling and simulation. Based upon the exposure of vancomycin in the renal tubule, the toxicity of vancomycin in human renal proximal tubular epithelial cells was examined with the XTT assay and in vitro metabolomics analysis. A rat PBPK model predicting plasma and kidney concentration-time profiles of vancomycin matched the observed behavior after a single administration of 10 mg/kg. The concentration of vancomycin in renal tubules was about 40-50 times higher than that in plasma. The human PBPK model transferred from the rat model predicted renal tubule concentrations of vancomycin as 316.1-2136.6 µg/mL at 500 mg every 6 hours, and 199.0-3932.5 µg/mL at 1000 mg every 12 hours. Vancomycin showed significant nephrotoxicity at 4 mg/mL in XTT assessment. In total, 11 lysophosphatidylcholines and one lysophosphatidylethanolamine were identified by metabolomics analysis. The concentration-dependent increase was evident in the release of lysophospholipids after vancomycin treatment (0.125-4 mg/mL) for 24 hours. Our study revealed the relationship between the exposure of vancomycin in the kidney and toxicity of vancomycin at clinically relevant concentrations achieved from a mechanical PBPK model. A series of lysophospholipids as potential metabolic markers of renal toxicity were identified.
Assuntos
Nefropatias/induzido quimicamente , Nefropatias/diagnóstico , Nefropatias/metabolismo , Túbulos Renais/efeitos dos fármacos , Rim/efeitos dos fármacos , Vancomicina/metabolismo , Vancomicina/farmacocinética , Vancomicina/toxicidade , Adulto , Antibacterianos/sangue , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Antibacterianos/toxicidade , Células Cultivadas/efeitos dos fármacos , Feminino , Humanos , Rim/química , Túbulos Renais/química , Masculino , Metabolômica , Modelos Animais , Testes de Toxicidade , Vancomicina/sangue , Adulto JovemRESUMO
Primary enteric adenocarcinoma is a rare variant of primary pulmonary adenocarcinoma. This disease lacks a distinctive manifestation and often requires pathological examination to make a definite diagnosis. A male patient visited the Second Xiangya Hospital, Central South University for consistent cough and sputum production for about 1 year. Anti-infection therapy was given but it showed ineffectiveness. Enteric adenocarcinoma was diagnosed after percutaneous lung biopsy according to pathological findings. Combining this case with relevant literature, we summarized the characteristics to raise physicians' awareness for this rare subtype.
Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Humanos , Pulmão , MasculinoRESUMO
OBJECTIVES: We compared the efficacy, safety, and cost-effectiveness of ultrasound-guided percutaneous polidocanol injection and percutaneous ethanol injection for the treatment of benign cystic and predominantly cystic thyroid nodules. METHODS: A total of 135 cystic thyroid nodules treated by percutaneous ethanol injection and 136 cystic thyroid nodules treated by percutaneous polidocanol injection were enrolled retrospectively in this study from May 2010 to March 2016. The nodules were followed after 1, 3, 6, and 12 months. Nodule volumes, symptoms scores, and cosmetic scores were assessed before treatment and at follow-up. The therapeutic success rate, safety, and cost-effectiveness between the groups were also compared. RESULTS: No significant differences in the reduction of the nodule volume, volume reduction rate, and therapeutic success were observed between the groups with cystic and predominantly cystic thyroid nodules during follow-up (P > .05). Neither the cosmetic scores (P = .59; P = .42) nor the symptom scores (P = .32; P = .73) in the cystic and predominantly cystic nodules were significantly different between the groups at the last follow-up. The complication rates for ethanol were higher than those for polidocanol (P < .05). However, the cost of polidocanol injection was higher than that of ethanol injection for cystic thyroid nodules (mean ± SD, US$97.18 ± US$22.17 versus US$43.36 ± US$5.51; P < .01). CONCLUSIONS: Ultrasound-guided percutaneous polidocanol injection can be an alternative for sclerotherapy of cystic or predominantly cystic thyroid nodules. However, its cost was higher than that of percutaneous ethanol injection.
Assuntos
Etanol/uso terapêutico , Polietilenoglicóis/uso terapêutico , Soluções Esclerosantes/uso terapêutico , Escleroterapia/métodos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/terapia , Ultrassonografia de Intervenção/métodos , Adolescente , Adulto , Idoso , Análise Custo-Benefício , Etanol/administração & dosagem , Etanol/economia , Feminino , Seguimentos , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Polidocanol , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/economia , Estudos Retrospectivos , Soluções Esclerosantes/administração & dosagem , Soluções Esclerosantes/economia , Escleroterapia/economia , Glândula Tireoide/diagnóstico por imagem , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Coagulase-negative staphylococci (CoNS) are recognized as a large reservoir of staphylococcal cassette chromosome mec (SCCmec) harboured by Staphylococcus aureus. However, data of SCCmec in CoNS are relatively absent particularly in China. METHODS: Seventy-eight CoNS clinical and 47 community isolates were collected in Beijing. PCR was performed to classify SCCmec types. Under oxacillin treatment, quantitative real-time reverse transcription PCR (qRT-PCR) was performed to compare mecA mRNA levels and mRNA half-life between isolates with single SCCmec element and those with multiple one. Their growth curves were analysed. Their bacterial cell wall integrity was also compared by performing a Gram stain. All ccr complex segments were sequenced and obtained ccr segments were analysed by phylogenetic analyses. RESULTS: All 78 clinical isolates had mecA segments compared with 38% in community isolates (total 47). Only 29% clinical isolates and 33% community isolates (among mecA positive isolates) harboured a single previously identified SCCmec type; notably, 17% clinical isolates and 28% community isolates had multiple SCCmec types. Further studies indicated that isolates with multiple SCCmec elements had more stable mecA mRNA expression compared with isolates with single SCCmec elements. CoNS with multiple SCCmec elements demonstrated superior cell wall integrity. Interestingly, phylogenetic analyses of obtained 70 ccr segments indicated that horizontal gene transfer of the ccr complex might exist among various species of clinical CoNS, community CoNS and S. aureus. CONCLUSIONS: CoNS recovered from patients carried extremely diverse but distinctive SCCmec elements compared with isolates from the community. More attention should be given to CoNS with multiple SCCmec not only because they had superior cell wall integrity, but also because CoNS and S. aureus might acquire multiple SCCmec through the ccr complex.
Assuntos
Cromossomos Bacterianos/genética , Coagulase/análise , Resistência a Meticilina/genética , Recombinases/genética , Staphylococcus aureus/genética , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Pequim , China , DNA Bacteriano/genética , Transferência Genética Horizontal , Genes Bacterianos , Humanos , Testes de Sensibilidade Microbiana , Oxacilina/farmacologia , Proteínas de Ligação às Penicilinas/genética , Filogenia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/isolamento & purificaçãoRESUMO
The technology of robot-assisted prostate seed implantation has developed rapidly. However, during the process, there are some problems to be solved, such as non-intuitive visualization effects and complicated robot control. To improve the intelligence and visualization of the operation process, a voice control technology of prostate seed implantation robot in augmented reality environment was proposed. Initially, the MRI image of the prostate was denoised and segmented. The three-dimensional model of prostate and its surrounding tissues was reconstructed by surface rendering technology. Combined with holographic application program, the augmented reality system of prostate seed implantation was built. An improved singular value decomposition three-dimensional registration algorithm based on iterative closest point was proposed, and the results of three-dimensional registration experiments verified that the algorithm could effectively improve the three-dimensional registration accuracy. A fusion algorithm based on spectral subtraction and BP neural network was proposed. The experimental results showed that the average delay of the fusion algorithm was 1.314 s, and the overall response time of the integrated system was 1.5 s. The fusion algorithm could effectively improve the reliability of the voice control system, and the integrated system could meet the responsiveness requirements of prostate seed implantation.
Assuntos
Algoritmos , Realidade Aumentada , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Próstata , Neoplasias da Próstata , Robótica , Humanos , Masculino , Robótica/instrumentação , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Próstata/diagnóstico por imagem , Imageamento Tridimensional , Voz , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Holografia/métodos , Holografia/instrumentação , Braquiterapia/instrumentação , Reprodutibilidade dos TestesRESUMO
BACKGROUND: At present, the number and overall level of ultrasound (US) doctors cannot meet the medical needs, and the medical ultrasound robots will largely solve the shortage of medical resources. METHODS: According to the degree of automation, the handheld, semi-automatic and automatic ultrasound examination robot systems are summarised. Ultrasound scanning path planning and robot control are the keys to ensure that the robot systems can obtain high-quality images. Therefore, the ultrasound scanning path planning and control methods are summarised. The research progress and future trends are discussed. RESULTS: A variety of ultrasound robot systems have been applied to various medical works. With the continuous improvement of automation, the systems provide high-quality ultrasound images and image guidance for clinicians. CONCLUSION: Although the development of medical ultrasound robot still faces challenges, with the continuous progress of robot technology and communication technology, medical ultrasound robot will have great development potential and broad application space.
Assuntos
Robótica , Ultrassonografia , Humanos , Ultrassonografia/métodos , Ultrassonografia/instrumentação , Robótica/instrumentação , Desenho de Equipamento , Automação , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Processamento de Imagem Assistida por Computador/métodosRESUMO
Fibers crystallize and become brittle at high temperatures for a long time, so the surface coating must maintain long-lasting emission performance, which requires superior antioxidant properties of the high-emissivity fillers. To improve the radiation performance of the coating and the tensile strength of the fiber fabric, a double-layer coating with high emissivity was prepared on the surface of flexible aluminum silicate fiber fabric (ASFF) using MoSi2 and SiC as emissive agents. The incorporation of borosilicate glass into the outer coating during high-temperature oxidation of ZrB2 results in superior encapsulation of emitter particles, effectively filling the pores of the coating and significantly reducing the oxidation rate of MoSi2 and SiC. Furthermore, the addition of an intermediate ZrO2 layer enhances the fiber bundle's toughness. The obtained double-coated ASFF exhibits an exceptionally high tensile strength of 57.6 MPa and a high bond strength of 156.2 kPa. After being subjected to a 3 h heating process, the emissivity exhibits a minimal decrease of only 0.032, while still maintaining a high value above 0.9. The thermal insulation composites, consisting of a flexible ASFF matrix and a ZrB2-modified double-layer coating, exhibit significant potential for broad applications in the field of thermal protection.
RESUMO
Ceramic fiber thread is one of the key components in flexible external thermal insulation blankets, and it has been applied in various fields as a flexible ceramic fibrous material with excellent deformability and high-temperature resistance. However, ceramic fiber threads are often subjected to reciprocating friction motion at specific bending angles, making them highly susceptible to abrade and fracture. Enhancing the abrasion resistance performance of ceramic fiber threads under bending conditions is the future trend and remains a significant challenge. Hence, we design and construct a novel polyurethane-modified coating on the ceramic fiber threads to improve their abrasion resistance performance. The effects of the types and concentrations of modifiers on the microstructure, abrasion resistance property, and tensile property of ceramic fiber threads are systematically investigated. The ceramic fiber threads, after modification with hexamethylene diisocyanate waterborne polyurethane (HDI-WPU) with a concentration of 3%, exhibit excellent abrasion resistance properties. The number of friction cycles at fracture of the modified ceramic fiber thread is more than three times, and the tensile strength is more than one and a half times, that of the original ceramic fiber thread, demonstrating the great potential of the HDI-WPU modifier for enhancing the abrasion resistance performance of ceramic fiber threads.
RESUMO
The Applications of silica aerogel are limited due to its brittleness and low strength. As a result, it is essential to strengthen and toughen it. Organic nanofibers are one of the preferred reinforcement materials. In this work, we designed and fabricated flexible and compressible nanostructure-assembled aramid nanofiber/silica composites aerogel (ANF/SiO2 aerogel) to improve the mechanical strength and flexibility of silica aerogel without compromising thermal insulation properties. The aramid nanofiber/silica composite aerogels were prepared by immersing the aramid nanofiber wet gel into the silica sol for a certain period of time followed by freeze drying without solvent replacement. The surface modifier 3-aminopropyltriethoxysilane (APTES) was used as a coupling agent to form chemical linkage between the ANF fiber and silica gel. It was observed that APTES can effectively drive the silica sol to infuse into ANF hydrogel, promoting the assembly of silica gel onto the fiber surface and a uniform distribution in the network of ANF. The compressive resilience, thermal stability, and thermal insulation properties of the composite aerogels were evaluated by inducing the silica aerogel into the ANF network to form a protective layer on the fiber and change the pore structure in the ANF network.
RESUMO
The oxygenation of Fe(II)-bearing minerals for hydroxyl radicals (HOâ¢) formation and contaminant attenuation receives increasing attentions. However, information on dissolved organic matter (DOM) with different types, concentrations, and molecular weights (MWs) in manipulating HO⢠formation and contaminant attenuation during mineral oxygenation remain unclear. In this study, four iron-pillared montmorillonites (IPMs) and two DOM samples [e.g., humic acids (HA) and fulvic acids (FA)] were prepared to explore the HO⢠formation and phenanthrene attenuation during the oxygenation of IPMs in the presence or absence of DOMs. Results showed that iron-pillared and high-temperature calcination procedures extended the interlayer domain of IPMs, which provided favorable conditions for a high HO⢠production from 1293 to 14537 µmol kg-1. The surface-absorbed/low crystalline Fe(â ¡) was the predominant Fe(â ¡) fractionations for HO⢠production, and presence of DOMs significantly enhanced the HO⢠production and phenanthrene attenuation. Moreover, regardless of the types and concentrations, the low MW (LMW, <1 kDa) fraction within DOM pool contributed highest to HO⢠production and phenanthrene attenuation, followed by the bulk and high MW (HMW-, 1 kDaâ¼0.45 µm) fractions, and FA exhibited more efficient effects in promoting HO⢠production and phenanthrene attenuation than HA. The fluorescent spectral analysis further revealed that phenolic-like fluorophores in LMW-fraction were the main substances responsible for the enhanced HO⢠production and phenanthrene attenuation. The results deepen our understandings toward the behaviors and fate of aquatic HO⢠and contaminants, and also provide technical guidance for the remediation of contaminated environments.
Assuntos
Ferro , Fenantrenos , Ferro/química , Matéria Orgânica Dissolvida , Radical Hidroxila/química , Bentonita , Compostos Ferrosos , Substâncias Húmicas/análiseRESUMO
Wounds infected with multidrug-resistant (MDR) bacteria are increasingly threatening public health and challenging clinical treatments because of intensive bacterial colonization, excessive inflammatory responses, and superabundant oxidative stress. To overcome this malignant burden and promote wound healing, a multifunctional cryogel (HA/TA2/KR2) composed of hyaluronic acid (HA), tannic acid (TA), and KR-12 peptides is designed. The cryogel exhibited excellent shape-memory properties, strong absorption performance, and hemostatic capacity. In vitro experiments demonstrated that KR-12 in the cryogel can be responsively released by stimulation with hyaluronidase produced by bacteria, reaching robust antibacterial activity against Escherichia coli (E. coli), MDR Pseudomonas aeruginosa (MDR-PA), and methicillin-resistant Staphylococcus aureus (MRSA) by disrupting bacterial cell membranes. Furthermore, the synergetic effect of KR-12 and TA can efficiently scavenge ROS and decrease expression of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α & interleukin (IL)-6), as well as modulate the macrophage phenotype toward the M2 type. In vivo animal tests indicated that the cryogel can effectively destroy bacteria in the wound and promote healing process via accelerating angiogenesis and re-epithelialization. Proteomic analysis revealed the underlying mechanism by which the cryogel mainly reshaped the infected wound microenvironment by inhibiting the Nuclear factor kappa B (NF-κB) signaling pathway and activating the Janus kinase-Signal transducer and activator of transcription (JAK-STAT6) signaling pathway. Therefore, the HA/TA2/KR2 cryogel is a promising dressing candidate for MDR bacteria-infected wound healing.
Assuntos
Antibacterianos , Criogéis , Modelos Animais de Doenças , Hialuronoglucosaminidase , Espécies Reativas de Oxigênio , Cicatrização , Animais , Camundongos , Antibacterianos/farmacologia , Criogéis/farmacologia , Criogéis/química , Escherichia coli/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Hialuronoglucosaminidase/metabolismo , Inflamação/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Camundongos Endogâmicos BALB CRESUMO
To explore the analysis on application effect and prognostic factors of medical care combined with nursing in the elderly with type 2 diabetes mellitus (T2DM) and cerebral infraction (CI) based on targeted management mode. The clinical data of 180 elderly patients with T2DM and CI in our hospital from August 2017 to August 2019 were selected for retrospective analysis. Their cognitive function and daily living ability before and after intervention were evaluated, using the National Institutes of Health Stroke Scale (NIHSS) to evaluate their prognosis. They were divided into good prognosis group (n = 134) and poor prognosis group (n = 46) according to the score. Binary Logistic regression analysis was adopted to analyze the prognostic factors of such patients. After intervention, patients had visibly lower indexes of blood glucose fluctuation and lower average scores of ADL and MMSE (P < 0.001), with differences in body mass index, systolic pressure, diastolic pressure, fasting blood glucose and triglyceride in both groups (P < 0.001). Binary Logistic regression analysis showed that systolic pressure, diastolic pressure and triglyceride were risk factors affecting patients' prognosis (P < 0.05). Medical care combined with nursing based on targeted management mode has a remarkable control effect on blood glucose, and has a positive effect on improving cognitive function and living ability of elderly patients with T2DM and CI. In addition, attention should be paid to monitoring systolic and diastolic blood pressures, and triglyceride in patients to improve the prognosis.
RESUMO
The heavy metal Cd can cause severe toxicity on aquatic algae, but there are few studies on the cytotoxicity of heavy metal on algae based on synchrotron radiation technology. In this study, synchrotron radiation-based Fourier transform infrared spectromicroscopy (SR-FTIR) was used to characterize in vivo the toxic effects of Cd on Cosmarium sp. cells, emphasizing the influence of dissolved organic matter (DOM) on Cd toxicity. Results showed that, in the absence of DOM, obvious growth inhibition, cell volume reduction, and photosynthesis disruption could be observed with increasing Cd concentrations (0-500 µg/L). Based on the SR-FTIR imaging and functional group quantification, it was shown that the biosynthesis of biomolecules such as proteins, lipids, and carbohydrates was inhibited in algal cells. However, the addition of DOM caused significant heterogeneities in biomacromolecule biosynthesis that an increased biosynthesis of carbohydrates and structural lipids but an inhibited biosynthesis of proteins and storage lipids were observed. Furthermore, the correlation analysis and principal component analysis showed a good correlation between v(C-OH)/Amide II and biochemical parameters, indicating that changes of carbohydrates could be used as the biomarker to indicate the cytotoxicity of heavy metals to algal cells. These findings provide insight into the mechanisms of heavy metal cytotoxicity to aquatic algae and systematic cytotoxicity assessment under various aquatic conditions.
Assuntos
Clorófitas , Metais Pesados , Cádmio/análise , Matéria Orgânica Dissolvida , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Síncrotrons , Clorófitas/metabolismo , Plantas/metabolismo , Carboidratos , LipídeosRESUMO
As a green and sustainable strategy, the electrocatalytic N2 reduction reaction (NRR) has been considered the best potential approach to replace the traditional Haber-Bosch process under ambient conditions. The key is to exploit efficient and low-cost electrocatalysts according to the current situation. Herein, a series of Molybdenum (Mo) doped CeO2 nanorods (NR) catalysts were successfully fabricated via a hydrothermal reaction coupled with high temperature calcination. The nanorod structures were not altered after Mo atom doping. The obtained 5 %-Mo-CeO2 nanorods act as a superior electrocatalyst in neutral electrolytes of 0.1â M Na2 SO4 . Such electrocatalyst significantly enhances NRR performance with an NH3 yield of 10.9â µg h-1 mg-1 cat at -0.45â V vs reversible hydrogen electrode (RHE) and a Faradaic efficiency (FE) of 26.5 % at -0.25â V vs RHE. That outcome is 4â times higher than that of CeO2 nanorods (2.6â µg h-1 mg-1 cat ; 4.9 %). Meanwhile, density functional theory (DFT) calculation shows the characteristics after Mo doping: the band gap value lowers, the density of states increases, electrons are more easily excited, and N2 molecules are more easily adsorbed, thereby enhancing the activity of the electrocatalytic NRR.