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1.
Small ; : e2403527, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031094

RESUMO

Recently, chloroperoxidase (CPO)-mediated enzyme dynamic therapy (EDT) by mimicking the antipathogen function of neutrophils via generating highly active signet oxygen (1O2) has attracted great interest in biomedical applications. However, the therapeutic efficiency of EDT is largely restricted by the low CPO delivery efficiency and insufficient hydrogen peroxide (H2O2) supply. In the present work, a neutrophil-mimicking nanozyme of MGBC with high CPO delivery efficiency, H2O2 self-supply, and enzyme-cascade catalytic properties is designed for high-efficient treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. In the infection microenvironment, MGBC can effectively catalyze glucose to self-supply substantial H2O2, which enables long-lasting 1O2 generation via the CPO-mediated catalytic reaction. At the meantime, MGBC can also catalyze H2O2 to sustainably release NO for gas therapy (GT), which synergistically strengthens the therapeutic effect of EDT. As a result, MGBC displayed effective MRSA-killing and MSRA biofilms-eradicating properties, and high efficiency in treating both MRSA infected full-thickness excision wounds and subcutaneous MRSA infection by exerting the synergistic bimodal EDT/GT therapeutic effects. In-depth mechanism study revealed that the synergistic EDT/GT antibacterial effects of MGBC can attenuate the drug resistance and toxicity of MRSA by significantly downregulating quorum sensing, multidrug efflux, virulence, and biofilm formation-related genes.

2.
Sensors (Basel) ; 23(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38139662

RESUMO

Parametric splines are popular tools for precision optical metrology of complex freeform surfaces. However, as a promising topologically unconstrained solution, existing T-spline fitting techniques, such as improved global fitting, local fitting, and split-connect algorithms, still suffer the problems of low computational efficiency, especially in the case of large data scales and high accuracy requirements. This paper proposes a speed-improved algorithm for fast, large-scale freeform point cloud fitting by stitching locally fitted T-splines through three steps of localized operations. Experiments show that the proposed algorithm produces a three-to-eightfold efficiency improvement from the global and local fitting algorithms, and a two-to-fourfold improvement from the latest split-connect algorithm, in high-accuracy and large-scale fitting scenarios. A classical Lena image study showed that the algorithm is at least twice as fast as the split-connect algorithm using fewer than 80% control points of the latter.

3.
BMC Neurosci ; 23(1): 74, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36482320

RESUMO

BACKGROUND: Sodium formononetin-3'-sulphonate (Sul-F) may alleviate I/R injury in vivo with uncertain mechanism. Endoplasmic reticulum (ER) stress-mediated apoptosis participates in the process of cerebral ischemia-reperfusion (I/R) injury. Our aim is to figure out the effect of Sul-F on cerebral I/R injury and to verify whether it works through suppressing ER stress-mediated apoptosis. RESULTS: The cerebral lesions of middle cerebral artery occlusion (MCAO) model in SD rats were aggravated after 24 h of reperfusion, including impaired neurological function, increased infarct volume, intensified inflammatory response and poor cell morphology. After intervention, the edaravone (EDA, 3 mg/kg) group and Sul-F high-dose (Sul-F-H, 80 mg/kg) group significantly alleviated I/R injury via decreasing neurological score, infarct volume and the serum levels of inflammatory factors (TNF-α, IL-1ß and IL-6), as well as alleviating pathological injury. Furthermore, the ER stress level and apoptosis rate were elevated in the ischemic penumbra of MCAO group, and were significantly blocked by EDA and Sul-F-H. In addition, EDA and Sul-F-H significantly down-regulated the ER stress related PERK/eIF2α/ATF4 and IRE1 signal pathways, which led to reduced cell apoptosis rate compared with the MCAO group. Furthermore, there was no difference between the EDA and Sul-F-H group in terms of therapeutic effect on cerebral I/R injury, indicating a therapeutic potential of Sul-F for ischemic stroke. CONCLUSIONS: Sul-F-H can significantly protects against cerebral I/R injury through inhibiting ER stress-mediated apoptosis in the ischemic penumbra, which might be a novel therapeutic target for ischemic stroke.


Assuntos
AVC Isquêmico , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Sódio , Estresse do Retículo Endoplasmático , Traumatismo por Reperfusão/tratamento farmacológico , Apoptose
4.
J Orthop Surg Res ; 19(1): 445, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075599

RESUMO

PURPOSE: To assess the clinical efficacy of arthroscopic treatment for posterior cruciate ligament (PCL) tibial avulsion fractures using high-intensity suture binding combined with button plate suspension fixation. METHODS: We retrospectively analyzed clinical data from 32 patients with PCL tibial avulsion fractures treated at our hospital from July 2020 to August 2023. We recorded operation time, intraoperative and postoperative complications, and used imaging to assess fracture reduction and healing. Pain and knee function were evaluated using the Visual Analogue Scale (VAS), range of knee motion, Lysholm score, and International Knee Documentation Committee (IKDC) score. STUDY DESIGN: Case series; Level of evidence, 4. RESULTS: All patients were followed for 6 to 18 months, averaging 13.6 months. All incisions healed successfully without postoperative complications. X-rays taken on the first postoperative day showed satisfactory fracture reduction. Three-month post-surgery imaging confirmed healed fractures and no internal fixation failures. At the final follow-up, knee function was well recovered, with only one patient exhibiting a positive posterior drawer test of degree I. Furthermore, the mean VAS score was 0. 5 (range 0.0 to 1.0), active knee extension was 2. 2° (range 0.0 to 5.0), and active knee flexion was 137.7° (range 130.0 to 145.0). The mean Lysholm score was 91.5(range 89.3 to 94.0), and the IKDC score averaged 83.8 ± 3.7, and these outcomes showed statistically significant improvement from preoperative levels (P < 0.001). CONCLUSIONS: Arthroscopic high-intensity suture binding combined with button plate suspension fixation for PCL tibial avulsion fractures offers several benefits: it is minimally invasive, results in less postoperative pain, enables earlier functional exercise, and provides satisfactory clinical outcomes with fewer complications.


Assuntos
Artroscopia , Placas Ósseas , Fixação Interna de Fraturas , Fratura Avulsão , Ligamento Cruzado Posterior , Fraturas da Tíbia , Humanos , Masculino , Adulto , Feminino , Artroscopia/métodos , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico por imagem , Estudos Retrospectivos , Ligamento Cruzado Posterior/cirurgia , Ligamento Cruzado Posterior/lesões , Pessoa de Meia-Idade , Resultado do Tratamento , Fixação Interna de Fraturas/métodos , Fratura Avulsão/cirurgia , Fratura Avulsão/diagnóstico por imagem , Adulto Jovem , Técnicas de Sutura , Seguimentos , Amplitude de Movimento Articular
5.
ACS Appl Mater Interfaces ; 16(7): 8378-8390, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38326945

RESUMO

Slow healing at the tendon-bone interface is a prominent factor in the failure of tendon repair surgeries. The development of functional biomaterials with 3D gradient structures is urgently needed to improve tendon-bone integration. The crystalline form of hydroxyapatite (HAP) has a crucial impact on cell behavior, which directly influences protein adsorption, such as bone morphogenetic protein 2, the adhesion, proliferation, and osteogenic differentiation with cells. This work aimed to generate gradient mineral structures in situ by stabilizing calcium and phosphate ions using a polymer-induced liquid precursor process. To regulate the crystalline growth of HAP at the interface of ß-chitin, this work made use of the surface properties of the organic matrix found in cuttlefish bone. These techniques allowed us to prepare an organic-inorganic composite gradient scaffold comprising plate-like HAP mineralized in situ on the surface of the scaffold and fibrous HAP in the scaffold's interior. Organic-inorganic composite gradient materials are anticipated for use in tendon-bone healing produced via the in situ construction of gradient-distributed HAP mineralization layers having varying crystalline morphologies on chitin scaffolds that possess a three-dimensional bionic structure.


Assuntos
Durapatita , Osteogênese , Durapatita/química , Alicerces Teciduais/química , Quitina , Biônica , Engenharia Tecidual
6.
J Pharm Biomed Anal ; 249: 116340, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38986349

RESUMO

Zuojin Pill (ZJP), a traditional Chinese medicine prescription composed of Rhizoma Coptidis and Euodiae Fructus in the ratio of 6:1 (w/w), has been widely used for the treatment of gastric disorders. However, an in-depth understanding of in vivo metabolism and distribution profiles of protoberberine alkaloids (PBAs) and indole alkaloids (IDAs) in ZJP is lacking. In this study, a method using ultra-high performance liquid chromatography coupled with quadruple time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was developed to systematically screen the alkaloids and their metabolites in rat plasma and various tissues after oral administration of ZJP. Furthermore, bioinformatics and molecular docking analyses were conducted to elucidate the contribution of the alkaloids and metabolites enriched in the stomach to the therapeutic effect of ZJP on gastritis. A total of 33 compounds, including 7 prototype alkaloids and 26 metabolites, were chemically defined or tentatively identified in this work. The metabolic pathways of PBAs (hydroxylation, oxidation, reduction, demethylation, demethylenation, glucuronide conjugation, sulfate conjugation) and IDAs (hydroxylation, glucuronide conjugation) were revealed. Notably, 7 prototype alkaloids and 18 metabolites were detected in the stomach, indicating their propensity for gastric distribution. These alkaloids and metabolites showed strong affinities with the 7 hub targets associated with gastritis, such as CCR7, CXCR4, IL6, IFNG, CCL2, TNF, and PTPRC, and could be considered the potential active substances of ZJP for treating gastritis. In conclusion, this study clarified the gastric distribution propensity of PBAs and IDAs and their metabolites, as well as their favorable binding interactions with gastritis-related targets, which could provide essential data for the further study of the pharmacodynamic material basis and gastroprotective mechanism of ZJP.


Assuntos
Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Ratos Sprague-Dawley , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão/métodos , Administração Oral , Ratos , Masculino , Biologia Computacional/métodos , Espectrometria de Massas em Tandem/métodos , Alcaloides/administração & dosagem , Alcaloides/análise , Alcaloides/química , Alcaloides/farmacocinética , Alcaloides Indólicos/farmacocinética , Alcaloides Indólicos/química , Alcaloides Indólicos/administração & dosagem , Alcaloides Indólicos/metabolismo , Alcaloides de Berberina/farmacocinética , Alcaloides de Berberina/análise , Espectrometria de Massas/métodos
7.
Clin Interv Aging ; 19: 883-889, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784158

RESUMO

Objective: To compare the clinical efficacy of artificial total hip arthroplasty(THA) for femoral neck fracture between direct anterior approach(DAA) in lateral position and posterior lateral approach(PLA). Methods: Comparison of 200 cases of patients who underwent THA collected between September 2019 and August 2021 was done. Incision length, intraoperative bleeding, operative time, difference in postoperative haemoglobin from preoperative levels, length of hospital stay, postoperative time to get off the floor, visual analogue score (VAS) for pain, preoperative and postoperative Harris scores for the hip, and measurements of the acetabular abduction angle and anterior acetabular tilt angle at 6 months postoperatively were collected, and all the cases were followed up for at least 2 years. Results: Compared with the PLA group, the DAA group had a shorter incision length, less intraoperative blood loss, less postoperative haemoglobin reduction compared with the preoperative period, a shorter hospital stay and an earlier first time to get off the floor after surgery, however, the comparison of operative times was not statistically significant; Patients in the DAA group had a lower VAS in the early postoperative period compared to PLA; Patients in the DAA group had higher hip Harris scores at 6 weeks and 6 months postoperatively; There was no significant difference in acetabular abduction angle and acetabular anterior tilt angle between the two groups at 6 months postoperatively. Conclusion: Compared to PLA, DAA in THA is minimally invasive, has less pain, less bleeding, earlier time out of bed, shorter hospital stay, better early hip function, faster rehabilitation, and better joint stability.


Assuntos
Artroplastia de Quadril , Perda Sanguínea Cirúrgica , Fraturas do Colo Femoral , Tempo de Internação , Duração da Cirurgia , Humanos , Artroplastia de Quadril/métodos , Fraturas do Colo Femoral/cirurgia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Estudos Retrospectivos , Idoso de 80 Anos ou mais
8.
J Pharm Biomed Anal ; 251: 116447, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39197205

RESUMO

Cis-trans isomers of N-isobutyl-2E,4E,8Z,10E-dodecatetraenamide (DDA-E) and N-isobutyl-2E,4E,8Z,10Z-dodecatetraenamide (DDA-Z) are representative alkamides with numbness of tongue, anti-inflammatory and analgesic activities of Asari Radix et Rhizoma. However, their respective metabolic pathways and pharmacokinetic behaviors are still unknown. This study aim to investigate the metabolism of the two alkamides in vitro and in vivo using ultra-high-performance liquid chromatography-quadruple-time-of-flight mass spectrometry. Furthermore, a rapid, sensitive, and selective ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed to quantify DDA-E/Z in rat plasma. Results indicated that DDA-E and DDA-Z showed significant differences in metabolism and pharmacokinetics. Across all samples, 24 metabolites of DDA-E and 21 metabolites of DDA-Z were detected. A variety of pathways were involved in the production of these metabolites, mainly hydroxylation and oxidation. The linear range of DDA-E/Z was 1-2500 ng/mL (R2 = 0.9984), and the lowest quantification limit was 1 ng/mL. Precision, accuracy, extraction recovery, matrix effect, and stability of DDA-E/Z were within acceptable limits. Pharmacokinetic research was conducted using male Sprague-Dawley rats receiving intravenous (1 mg/kg) or intragastric (40 mg/kg) administration of DDA-E or DDA-Z solution. There was a calculated absolute bioavailability of 15.67 % for DDA-E and 4.83 % for DDA-Z when consumed orally. The apparent volume of distribution of intravenous and intragastric administrations were 4.44 ± 0.41 L/kg and 5.18 ± 0.67 L/kg for DDA-E, and 1.56 ± 1.66 L/kg and 2.35 ± 0.42 L/kg for DDA-Z. The maximal plasma concentrations of DDA-E and DDA-Z were 599.84 ± 149.92 nM and 422.09 ± 69.17 nM, and the time to maximum peak were 4.33 ± 3.51 h and 0.70 ± 1.12 h, respectively. In conclusion, in subsequent pharmacodynamics and safety evaluation studies, great attention should be paid to the metabolic characteristics and pharmacokinetic differences between DDA-E and DDA-Z.


Assuntos
Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Masculino , Ratos , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/análise , Isomerismo , Rizoma/química , Microssomos Hepáticos/metabolismo , Administração Oral
9.
J Ethnopharmacol ; 337(Pt 1): 118789, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39241971

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Peganum harmala L., a traditional Uyghur ethnic medicine widely used in China, is commonly used in the treatment of conditions such as hemiplegia, forgetfulness, cough, and asthma. Harmine and other ß-carboline alkaloids, one of the main active ingredients in P. harmala, have exhibited various pharmacological activities, including anti-Alzheimer's, antidepressant, anti-inflammatory, and antioxidant effects. However, the effects and underlying mechanisms of harmine on improving ethanol-induced memory impairment remain unclear. AIM OF THE STUDY: This study aimed to investigate the effects of harmine on ameliorating ethanol-induced memory impairment, and to explore potential mechanisms. MATERIALS AND METHODS: Ethanol (30%, i. g.) was used to induce memory impairment model. The effect of harmine on memory impairment was evaluated by Morris water maze (MWM). The histopathological analysis, immunofluorescence staining, RT-qPCR and UHPLC-MS/MS methods were performed to further investigate the underlying mechanisms. RESULTS: MWM experiments showed that harmine significantly improved ethanol-induced spatial learning memory deficit. Harmine exhibited anti-inflammatory effect by downregulating inflammatory factors such as IL-6, IL-1ß and tumor necrosis factor-α (TNF-α) induced by ethanol. Harmine also upregulated brain-derived neurotrophic factor (BDNF) levels to exert neuroprotective effect. Moreover, harmine protected neuronal cells and increased the protein expression of myelin basic protein (MBP). The cellular results indicated that harmine protected SH-SY5Y cells from ethanol-induced cytotoxicity and upregulated the relative mRNA expression of synaptosome associated protein 25 (SNAP25), syntaxin 1 A (STX1A), vesicle associated membrane protein 2 (VAMP2), synaptotagmin 1 (SYT1) and synaptophysin (SYP). CONCLUSIONS: Harmine improved ethanol-induced memory impairment by ameliorating inflammation, increasing BDNF levels, promoting synaptic vesicle fusion, protecting myelin sheath, and modulating neurotransmitter levels. These findings provided a scientific basis for development of therapeutic drugs for alcohol-induced memory impairments and other related disorders.

10.
J Orthop Surg Res ; 18(1): 728, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752567

RESUMO

BACKGROUND: Since arthroscopy was discovered to treat acromioclavicular joint injury, people have had great interest and attention to this beautiful and minimally invasive operation, and related research has been increasing worldwide. At present, there is no bibliometric and visualized analysis in this field. The purpose of this study is to explore the research hotspots and trends of arthroscopic treatment of acromioclavicular joint injury through bibliometric and visualized analysis and look forward to the future development direction of clinical practice. METHODS: The publications on arthroscopic treatment of acromioclavicular joint injury diseases from its establishment to April 2023 were obtained from the Web of Science (WOS) Core Collection database. CiteSpace, VOSviewer, Scimago graphica and Origin were used for bibliometric and visualized analysis. RESULTS: This study included a total of 330 publications. The number of publications tends to increase every year. The USA has the most significant number of publications and citations. Imhoff AB is the most relevant scholar with the largest number of publications in this field, and the scholar with the highest citation and average citations is Mazzocca AD. Tech Univ Munich, Rush University and Charite are the three institutions with the greatest contribution. Tech Univ Munich, Rush University and Charite are the three institutions with the greatest contribution. In addition, "Arthroscopy-the Journal of Arthroscopic and Related Surgery" and "American Journal of Sports Medicine" are the institutions with the most significant number of publications and average citations, respectively. The most common keywords are "acromioclavicular joint dislocation," "arthroscopic resection," "arthroscopic reconstruction" and "coracoclavicular ligament." CONCLUSION: The number of publications shows a steady upward trend as a whole. However, there is still a lack of cooperation among countries, institutions and scholars around the world, so various countries, institutions and scholars need to strengthen academic exchanges and expand the field of cooperation, so as to promote further research and development in related fields. However, minimally invasive methods such as arthroscopy are still the hotspots and frontiers in the treatment of acromioclavicular joint injury in the future.


Assuntos
Articulação Acromioclavicular , Artropatias , Luxação do Ombro , Humanos , Articulação Acromioclavicular/cirurgia , Bibliometria , Artroscopia , Bases de Dados Factuais
11.
Materials (Basel) ; 16(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629972

RESUMO

Mo, TiH2, Al and graphite elemental powders were used as starting materials for the activation reaction sintering process, which was employed to fabricate porous Mo2TiAlC2. The alteration of phase constitution, volume expansion, porosity, pore size and surface morphology of porous Mo2TiAlC2 with sintering temperatures ranging from 700 °C to 1500 °C were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and pore size tester. Both the pore formation mechanism and activation reaction process at each temperature stage were investigated. The experimental results illustrate that the sintered discs of porous Mo2TiAlC2 exhibit obvious volume expansion and pore structure change during the sintering process. Before 1300 °C, the volume expansion rate and porosity increase with the increment of temperature. However, with the sintering temperature above 1300 °C, the volume expansion rate and porosity decrease. At the final sintering temperature of 1500 °C, porous Mo2TiAlC2 with a volume expansion rate of 35.74%, overall porosity of 47.1%, and uniform pore structure was synthesized. The pore-forming mechanism of porous Mo2TiAlC2 is discussed, and the evolution of pressed pores, the removal of molding agents, the decomposition of TiH2, and the Kirkendall effect caused by different diffusion rates of elements in the diffusion reaction are all accountable for the formation of pores.

12.
J Mater Chem B ; 11(7): 1495-1505, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36655922

RESUMO

Currently, multidrug resistant (MDR) bacterial infections are a great threat to public health, and the development of novel strategies for high efficiency combatting of MDR bacteria is in urgent demand. Hydrogen (H2) is a small gas with a high reducing ability, and plenty of recent studies have demonstrated its therapeutic effect on many diseases. However, the antibacterial effectiveness and mechanism of H2 against MDR bacteria are still unknown. In the present work, using PdH nanohydride with a temperature responsive H2-releasing property as the H2 source, we demonstrated that H2 was not only able to inhibit the growth of normal Staphylococcus aureus (S. aureus), but could also effectively eliminate single drug resistant S. aureus (CRSA) and multidrug resistant S. aureus (MRSA), as well as the biofilms formed by those bacteria. Moreover, an in-depth mechanism regarding the anti-antibiotic-resistance activity of H2 was elucidated by us, in which H2 exerted its antibacterial effect by firstly causing severe membrane damage, followed by boosting generation of intracellular ROS, which subsequently triggered DNA damage and finally led to bacterial death. The proposed mechanism was further verified by genomic analysis, where a cluster of genes related to bacterial membrane integrity, biofilm formation, metabolism and DNA functions was significantly perturbed by the released H2. In particular, H2 boosted intracellular ROS generation by destroying the redox homeostasis of bacterial metabolism. More importantly, we revealed that H2 was able to alleviate the antibiotic resistance of CRSA and MRSA by significantly down-regulating the expression of many drug-resistant genes, e.g. the norG gene of CRSA, and fmtA, gpsB, sarA and marR genes of MRSA, as well as reducing the minimal inhibitory concentration (MIC) of ciprofloxacin/ampicillin against CRSA/MRSA. The findings in our work suggested that H2 therapy is a promising tool for combating antibiotic-resistant bacteria.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Espécies Reativas de Oxigênio , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico
13.
Nanomaterials (Basel) ; 13(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570476

RESUMO

Ce-MnOx composite oxide catalysts with different proportions were prepared using the coprecipitation method, and the CO-removal ability of the catalysts with the tested temperature range of 60-140 °C was investigated systematically. The effect of Ce and Mn ratios on the catalytic oxidation performance of CO was investigated using X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), H2 temperature programmed reduction (H2-TPR), CO-temperature programmed desorption (CO-TPD), and in situ infrared spectra. The experimental results reveal that under the same test conditions, the CO conversion rate of pure Mn3O4 reaches 95.4% at 170 °C. Additionally, at 140 °C, the Ce-MnOx series composite oxide catalyst converts CO at a rate of over 96%, outperforming single-phase Mn3O4 in terms of catalytic performance. With the decrement in Ce content, the performance of Ce-MnOx series composite oxide catalysts first increase and then decrease. The Ce MnOx catalyst behaves best when Ce:Mn = 1:1, with a CO conversion rate of 99.96% at 140 °C and 91.98% at 100 °C.

14.
Acta Biomater ; 143: 428-444, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35227899

RESUMO

Recently, nitric oxide (NO) has received increasing interest in combat against bacteria-induced infections because of its ability to sensitize and enhance the antibacterial effectiveness of many therapeutic approaches such as antibiotics. However, high-efficient loading and controlled release of NO remain a big challenge. In the present work, a type of gold nanostar/hollow polydopamine Janus nanostructure (GNS/HPDA JNPs) with precise near infrared (NIR)-controlled NO release property was fabricated using a facile seed-mediated method. Upon NIR laser irradiation, the NO-releasing GNS/HPDA JNPs (GNS/HPDA-BNN6) exhibited a synergistic photothermal and NO antibacterial effect by significantly inhibiting the growth and biofilm formation of both Gram-negative and Gram-positive bacterial strains, including methicillin-resistant Staphylococcus aureus (MRSA). An in-depth mechanism study revealed that two pathways were mainly involved in the synergistic photothermal and NO antibacterial effect. In one pathway, the synergistic effect severely destroyed the bacterial membrane by causing leakage of intracellular components such as DNA. In another pathway, the synergistic effect largely disturbed bacterial metabolism by regulating relative metabolic genes, followed by enhancing ROS generation to cause intracellular GSH depletion and DNA damage. More importantly, the synergistic effect significantly diminished the drug resistance of MRSA by downregulating the expression of the drug-resistant gene mecA and some relative multidrug efflux pumps (e.g., SepA and Tet38). An in vivo evaluation using a rat model with MRSA-infected wounds indicated that the synergistic photothermal and NO effect of GNS/HPDA-BNN6 can effectively eliminate MRSA from wounds, thereby alleviating inflammation and promoting wound healing. STATEMENT OF SIGNIFICANCE: Multidrug-resistant (MDR) bacteria have become a big threat to mankind, and therefore, the development of innovative antibacterial agents with high antibacterial efficiency is urgently required. Nanomaterial-mediated nitric oxide (NO) therapy is a promising strategy to effectively combat MDR bacteria through a synergistic antibacterial effect. Here, a gold nanostar/hollow polydopamine Janus nanostructure with precise near infrared (NIR) light-controlled NO release property (GNS/HPDA-BNN6) was developed. Both in vitro and in vivo evaluations demonstrated that GNS/HPDA-BNN6 could effectively eliminate methicillin-resistant Staphylococcus aureus (MRSA) from infected wounds and promote wound healing through a synergistic photothermal and NO therapeutic effect. Remarkably, the synergistic effect significantly diminished the drug resistance of MRSA by downregulating the expression of some drug-resistant genes and multidrug efflux pumps.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Nanopartículas Multifuncionais , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Ouro/farmacologia , Indóis , Lasers , Óxido Nítrico/farmacologia , Polímeros , Ratos , Cicatrização
15.
RSC Adv ; 12(36): 23584-23594, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090412

RESUMO

Exploring highly efficient and durable catalysts for the hydrogen evolution reaction (HER) is crucial for the hydrogen economy and environmental protection issues. Numerous studies have now found that transition metal carbide MXenes are ideal candidates as catalysts for the hydrogen evolution reaction. However, MXenes are inclined to easily undergo lamellar structure agglomeration and stacking, which impedes their further applications. Besides, most of the extant research has focused on single transition metal carbides, and the investigation of double transition metal carbide MXenes is rather rare. In this research work, a three-dimensional (3D) TiVCT x -based conductive electrode was constructed by depositing 2D TiVCT x nanosheets on 3D network structured nickel foam (NF) to synthesize a hybrid electrode material (abbreviated as TiVCT x @NF). TiVCT x @NF exhibits efficient electrochemical properties with a low overpotential of 151 mV at 10 mA cm-2 and a small Tafel slope of 116 mV dec-1. Benefitting from the open layer structure and strong interfacial coupling effect, compared to the pristine structure, the resulting TiVCT x @NF has greatly increased active sites for the hydrogen evolution reaction (HER) and encounters less resistance for charge transfer. In addition, TiVCT x @NF exhibits better stability in long-term acidic electrolytes. This work provides a tactic to prepare three-dimensional network electrode materials and broadens the application of single transition metal carbide MXenes as water splitting electrodes in the HER, which is beneficial to the application of noble metal-free electrocatalysts.

16.
Arch Virol ; 155(5): 657-63, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20229117

RESUMO

The purpose of our study was to investigate the expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1) and T-box 2 (TBX2) and its correlation with HPV16 infection in cervical squamous cell carcinoma (CSCC). HPV16 was detected by amplifying the HPV16 E7 gene by the polymerase chain reaction (PCR) method, and the expression of PSCA, PIWIL1, TBX2 and HPV16 E7 in 59 CSCCs and matched adjacent normal cervix (MANC) was examined by the streptavidin-peroxidase (SP) method. Fifty-two CSCCs and MANC specimens that were positive for the E7 gene and the E7 protein were identified as infected with HPV16 and included in present study. The rate of infection with HPV16 in CSCC was 52% (27/52), but that in matched adjacent normal cervix (MANC) samples was 4% (2/52). Infection with HPV16 was found to be statistically more frequent in CSCC (P = 0.000). The expression rates of PSCA, PIWIL1 and TBX2 in MANC were 6% (3/52), 8% (4/52) and 2% (1/52), respectively, but those in CSCC were 62% (32/52), 75% (39/52) and 52% (27/52), respectively. Higher expression rates of PSCA, PIWIL1 and TBX2 were observed in CSCC than in MANC (P = 0.000). HPV16 had a statistical positive correlation with PSCA, PIWIL1 and TBX2 in CSCC (P < 0.05). The increased expression of PSCA, PIWIL1 and TBX2 had no correlation with the patient's age or histological grade P > 0.05). The elevated expression of PSCA and PIWIL1 was associated with invasion of CSCC (P < 0.05). Up-regulated expression of TBX2 had a positive association with lymph node metastasis (P = 0.014). These findings demonstrate for the first time the expression of PSCA, PIWIL1 and TBX2 in CSCC. Their correlation with HPV16 might provide new basic information for investigating the molecular mechanism of HPV and help us to deepen our understanding of the interaction between HPV16 and host cells the carcinogenesis of CSCC.


Assuntos
Carcinoma de Células Escamosas/etiologia , Glicoproteínas de Membrana/análise , Proteínas de Neoplasias/análise , Proteínas E7 de Papillomavirus/análise , Proteínas/análise , Proteínas com Domínio T/análise , Neoplasias do Colo do Útero/etiologia , Antígenos de Neoplasias , Proteínas Argonautas , Carcinoma de Células Escamosas/virologia , Feminino , Formaldeído , Proteínas Ligadas por GPI , Humanos , Imuno-Histoquímica , Proteínas E7 de Papillomavirus/genética , Inclusão em Parafina , Neoplasias do Colo do Útero/virologia
17.
Onkologie ; 33(5): 241-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20502058

RESUMO

BACKGROUND: Endometrial cancer is the 4th most common gynecological cancer. The expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1), and T-box 2 (TBX2) in endometrial cancer remains to be elucidated. MATERIAL AND METHODS: The expression of PSCA, PIWIL1, and TBX2 was examined using the streptavidin-peroxidase method in 64 endometrial endometrioid adenocarcinoma (EAC) and paired normal endometrium (NE) samples from the Shaanxi Province in China. RESULTS: Positive expression rates of PSCA, PIWIL1, and TBX2 were 75% (48/64), 25% (16/64), and 56% (36/64), respectively in EACs, but 5% (3/64), 6% (4/64), and 2% (1/64), respectively in NEs. The difference was statistically significant (p < 0.05). PSCA was positively correlated with TBX2 (p = 0.003) but not PIWIL1 (p = 0.188). PIWIL1 was positively correlated with TBX2 (p = 0.003). PSCA was positively correlated with age, tumor grade, and lymph node metastasis (p < 0.05). TBX2 had an association with lymph node metastasis (p = 0.014). PIWIL1 was not associated with clinicopathological features (p > 0.05). CONCLUSIONS: We report the first analysis of PSCA, PIWIL1, and TBX2 expression in EAC. Our findings suggest that PSCA and TBX2 might be candidate targets for cancer therapy, and have helped us further understand the carcinogenesis of endometrial cancer.


Assuntos
Adenocarcinoma/genética , Neoplasias do Endométrio/genética , Regulação Neoplásica da Expressão Gênica/genética , Glicoproteínas de Membrana/genética , Proteínas de Neoplasias/genética , Proteínas/genética , Proteínas com Domínio T/genética , Adenocarcinoma/patologia , Adulto , Fatores Etários , Idoso , Antígenos de Neoplasias , Proteínas Argonautas , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Neoplasias do Endométrio/patologia , Endométrio/patologia , Feminino , Proteínas Ligadas por GPI , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática/patologia , Pessoa de Meia-Idade
18.
Onkologie ; 33(10): 500-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20926896

RESUMO

BACKGROUND: Apoptosis-stimulating protein of p53 (ASPP) family members can stimulate the apoptotic function of p53 but have no impact on its cell cycle arrest function. MATERIAL AND METHODS: The expression pattern of the ASPP family consisting of ASPP1, ASPP2, and iASPP was examined by immunohistochemistry in 45 formalin-fixed and paraffin-embedded endometrial endometrioid adenocarcinoma (EEA) specimens and 26 normal endometrial tissue (NET) samples. RESULTS: The expression rates of ASPP1 and ASPP2 in EEA were significantly lower than those in NET (p < 0.05). However, the iASPP expression rate in EEA was statistically higher in contrast to NET (p < 0.05). Expression of ASPP1 and iASPP in EEA had no correlation with any clinicopathological features (p > 0.05). iASPP was associated with grade, invasion, and lymph node metastasis (p < 0.05). CONCLUSIONS: It is a novel finding that the expression pattern of the ASPP family members has respective pathological and clinical implications in EEA, and iASPP might be a candidate target for EEA therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Repressoras/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo
19.
Onkologie ; 32(10): 574-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19816074

RESUMO

BACKGROUND: Esophageal cancer is the fourth most prevalent malignancy in China. The relationship between COX-2, CD44v6, and nm23H1 in esophageal squamous cell carcinoma (ESCC) remains unclear. MATERIAL AND METHODS: Expression of COX-2, CD44v6, and nm23H1 was examined, using the streptavidin-peroxidase method, in 82 ESCC and 30 normal esophageal mucosa (NEM) samples from the Shaanxi Province in China. RESULTS: The positive rates of COX-2, CD44v6, and nm23H1 were 73.2% (60/82), 64.6% (53/82), and 24.4% (31/82), respectively in ESCC, but 6.7% (2/30), 3.3% (1/30), and 90% (27/30), respectively in NEMs. There was a statistically significant difference between NEMs and ESCCs (p < 0.05). Expression of COX-2 showed a positive statistical correlation with expression of CD44v6 (r = 0.4732, p < 0.0001), and an inverse correlation with nm23H1 (r = -0.3226, p = 0.0035). Expression of COX-2, CD44v6, and nm23H1 had no significant correlation with gender or age (p > 0.05), but increased expression of COX-2 and CD44v6 showed statistical correlation with invasion and lymph node metastasis, respectively (p < 0.05). Decreased expression of nm23H1 was statistically correlated with lymph node metastasis (p = 0.0007) but had no correlation with invasion (p = 0.8221). CONCLUSIONS: This is the first report of a significant correlation between COX-2, CD44v6, and nm23H1 in ESCC. This knowledge might help us to further understand the molecular mechanisms of carcinogenesis and progression of ESCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/metabolismo , Ciclo-Oxigenase 2/análise , Neoplasias Esofágicas/metabolismo , Receptores de Hialuronatos/análise , Nucleosídeo NM23 Difosfato Quinases/análise , Proteínas de Neoplasias/análise , Carcinoma de Células Escamosas/epidemiologia , China/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
20.
Environ Sci Pollut Res Int ; 26(30): 30954-30966, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31452121

RESUMO

The study on the quantification of ecological compensation (eco-compensation) in a river basin can help to make environmental protection more compatible with ecological construction. In this paper, the upstream and downstream of the river basin were treated as the subjects and objects of eco-compensation, and the mechanism of eco-compensation was clarified. The emergy analysis theory (EMA) was used to calculate the values of water resources in sub-industries (agriculture, industry, life, and recreation). The pollution loss rate theory (PLR) was adopted to calculate the water pollution loss rate in sub-industries. According to the value of water resources and pollution loss rate in sub-industries, combined with the water consumption of sub-industries in the river basin, the Ecological Compensation Quantification Model of Sub-industries (ECQ-Is Model) was constructed. Under the guidance of the aforementioned theory and model, a comprehensive research was conducted on the Xiaohong River. The results showed that the eco-compensation values of the upstream area, industry, and agriculture in the river basin were higher. Therefore, it is essential that the water resources in the Xiaohong River basin be well conserved and managed. In addition, the research results point out the direction for water pollution control, which includes promoting the coordinated development of the upstream and downstream, and maximizing the ecological benefits of the river basin.


Assuntos
Modelos Teóricos , Poluição da Água/análise , Poluição da Água/economia , Agricultura , China , Conservação dos Recursos Naturais/métodos , Indústrias , Rios , Poluição da Água/prevenção & controle , Recursos Hídricos
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