Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 192
Filtrar
1.
Int J Biol Macromol ; 281(Pt 4): 136594, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39414207

RESUMO

Bamboo holds significant potential as a substitute for plastics. Stress relaxation is a critical property during the fixation stage of plastic formation for bamboo products intended to replace plastic. However, research on this topic has been limited. In this study, a custom-built mechanical loading platform coupled with Raman spectroscopy was acquired during stress relaxation of bamboo under different humidity levels. Results reveal variations in stress relaxation patterns based on node position, radial location, and humidity, along with changes in cellulose molecules in response to these factors. Specifically, stress relaxation modulus in bamboo decreases from the outer to the inner part, increases in the presence of node structures, and decreases with increasing humidity. The shifts in Raman spectral bands exhibit significant changes in response to variations in stress and humidity. The elongation of cellulose chain bands at 1097 cm-1 in the Raman spectrum shows an increasing trend during stress relaxation, with larger band shifts observed at lower humidity. Simulations of cellulose molecular stretching show a stronger stress response at lower moisture content, with a maximum stress of 0.85 GPa for cellulose at 3.3 % moisture content, compared to 0.79 GPa at 7.8 % moisture content. These findings suggest a novel approach for the molecular investigation of materials during stress relaxation, which is crucial for the plasticity processing of bamboo.

2.
J Nanobiotechnology ; 22(1): 596, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354525

RESUMO

Early diagnosis and treatment of gastric cancer (GC) play a vital role in improving efficacy, reducing mortality and prolonging patients' lives. Given the importance of early detection of gastric cancer, an electrochemical biosensor was developed for the ultrasensitive detection of miR-19b-3p by integrating MoS2-based nanozymes, hybridization chain reaction (HCR) with enzyme catalyzed reaction. The as-prepared MoS2-based nanocomposites were used as substrate materials to construct nanoprobes, which can simultaneously load probe DNA and HCR initiator for signal amplification. Moreover, the MoS2-based nanocomposites are also employed as nanozymes to amplify electrochemical response. The presence of miR-19b-3p induced the assembly of MoS2-based nanoprobes on the electrode surface, which can activate in-situ HCR reaction to load a large number of horseradish peroxidase (HRP) for signal amplification. Coupling with the co-catalytic ability of HRP and MoS2-based nanozymes, the designed electrochemical biosensor can detect as low as 0.7 aM miR-19b-3p. More importantly, this biosensor can efficiently analyze miR-19b-3p in clinical samples from healthy people and gastric cancer patients due to its excellent sensitivity and selectivity, suggesting that this biosensor has a potential application in early diagnosis of disease.


Assuntos
Técnicas Biossensoriais , Dissulfetos , Técnicas Eletroquímicas , Peroxidase do Rábano Silvestre , MicroRNAs , Molibdênio , Neoplasias Gástricas , Neoplasias Gástricas/diagnóstico , Humanos , MicroRNAs/genética , Molibdênio/química , Técnicas Eletroquímicas/métodos , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Técnicas Biossensoriais/métodos , Dissulfetos/química , Hibridização de Ácido Nucleico , Nanocompostos/química , Limite de Detecção
3.
Adv Mater ; 36(44): e2406429, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39254352

RESUMO

Aqueous zinc ion batteries have gained attention as viable energy storage systems, yet the occurrence of detrimental side reactions and Zn dendrite formation undermines the efficiency of Zn anodes. Controlling water activity have proven to be an effective strategy in mitigating these challenges. However, strategies such as electrolyte design and electrode protection layer show weakness to varying degrees. Here, a new oxygen-functionalized biomass bamboo membrane separator (denoted as BM) is proposed to restrain the activity of water molecules. This BM separator features a unique, multi-tiered 2D interlayer that facilitates rapid ion diffusion. Additionally, the oxygen functional groups of the BM separator can form hydrogen bonds with water molecules, effectively transforming water molecules from a free state to a bound state. Consequently, the Zn/Zn asymmetric coin cell using BM can work at the ultrahigh rate and capacity of 30 mA cm-2 and 30 mAh cm-2 for more than 80 h while its counterparts using glass fiber can barely work. Moreover, full cells using BM separator exhibited a capacity retention of 89.7% after 1000 cycles at 10 A g-1. This study reveals the important influence of water-limited activity on Zn anode protection and provides an avenue for the design of novel separator.

4.
Sci Data ; 11(1): 913, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179570

RESUMO

The testis serves as the primary site for spermatogenesis in mammals and is a crucial organ for the secretion of male hormones. Heat stress (HS) can have adverse effects on the seminiferous tubules, sperm quality, and sperm fertilization capability within the testis. Despite numerous previous studies describing various time points after heat stress in mice, a systematic and comprehensive dataset on heat stress and recovery in mice has been lacking. This study aimed to explore the gene expression changes in the recovery of multiple seminiferous epithelial cycles and spermatogenic cycles in mouse testicles after heat stress. We obtained high-throughput bulk RNA-seq data from testicular tissue of 4 NC mice and 32 HS mice (divided into 9 groups: NC, 30 min, 2 h, 6 h, 24 h, 3d, 8d, 24d, 47d, and 95d) and illustrated the dynamic changes in differential genes. This data set provides valuable insights into the detailed dynamic changes of one or more spermatogenic cycles after heat stress in mouse testicles, as well as the molecular mechanisms involved.


Assuntos
Resposta ao Choque Térmico , RNA-Seq , Espermatogênese , Testículo , Animais , Masculino , Camundongos , Testículo/metabolismo , Espermatogênese/genética
5.
Sci Data ; 11(1): 747, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982138

RESUMO

Infertility, a worldwide reproductive health concern, impacts approximately one in five couples. Male infertility, stemming from spermatogenic dysfunction and reduced sperm quality, stands as a primary factor contributing to infertility. Given the global decrease in male fertility linked to environmental factors like the greenhouse effect, it is crucial to develop a comprehensive understanding of how increased temperatures impact both the quantity and quality of sperm. In this study, we utilized Pandora-seq technology to detect the small non-coding RNAs (sncRNAs) expression profile in the testicular tissue of heat-stressed mice. The investigation explores the dynamic shifts in sncRNAs within the mouse testis under heat stress, including miRNAs, tsRNAs, piRNAs, rsRNAs and other sncRNAs. Furthermore, we successfully identified differentially expressed sncRNAs in testicular tissues before and after heat stress. Subsequently, we conducted functional enrichment analysis on the potential predicted target genes of differentially expressed miRNAs and tsRNAs. These datasets will constitute a valuable foundational resource for further investigations into the decline in male reproductive capacity triggered by heat stress.


Assuntos
Resposta ao Choque Térmico , Pequeno RNA não Traduzido , Testículo , Animais , Masculino , Camundongos , Infertilidade Masculina/genética , MicroRNAs/genética , Pequeno RNA não Traduzido/genética , Testículo/metabolismo
6.
Acta Biomater ; 185: 55-72, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38997078

RESUMO

Biodegradable Zn alloys have significant application potential for hard-tissue implantation devices owing to their suitable degradation behavior and favorable biocompatibility. Nonetheless, pure Zn and its alloys in the as-cast state are mechanically instable and low in strength, which restricts their clinical applicability. Here, we report the exceptional mechanical, corrosion, and biocompatibility properties of hot-extruded Zn-5RE (wt.%, RE = rare earth of Y; or Ho; or Er) alloys intended for use in biodegradable bone substitutes. The microstructural characteristics, mechanical behavior, corrosion resistance, cytocompatibility, osteogenic differentiation, and capacity of osteogenesis in vivo of the Zn-5RE alloys are comparatively investigated. The Zn-5Y alloy demonstrates the best tensile properties, encompassing a 138 MPa tensile yield strength, a 302 MPa ultimate tensile strength, and 63% elongation, while the Zn-5Ho alloy shows the highest compression yield strength of 260 MPa and Vickers hardness of 104 HV. The Zn-5Er alloy shows a 126 MPa tensile yield strength, a 279 MPa ultimate tensile strength, 52% elongation, a 196 MPa compression yield strength, and a 101 HV Vickers microhardness. Further, the Zn-5Er alloy has a 130 µm per year corrosion rate in electrochemical tests and a 26 µm per year degradation rate in immersion tests, which is the lowest among the tested alloys. It also has the best in vitro osteogenic differentiation ability and capacity for osteogenesis and osteointegration in vivo after implantation in rat femurs among the Zn-5RE alloys, indicating promising potential in load-bearing biodegradable internal bone-fixation applications. STATEMENT OF SIGNIFICANCE: This work reports the exceptional mechanical, corrosion, and biocompatibility properties of hot-extruded (HE) Zn-5 wt.%-rare earth (Zn-5RE) alloys using single yttrium (Y), holmium (Ho), and erbium (Er) alloying for biodegradable bone-implant applications. Our findings demonstrate that the HE Zn-5Er alloy showed σuts of 279 MPa, tensile yield strength of 126 MPa, elongation of 51.6%, compression yield strength of 196 MPa, and microhardness of 101.2 HV. Further, HE Zn-5Er showed the lowest electrochemical corrosion rate of 130 µm/y and lowest degradation rate of 26 µm/y, and the highest in vitro osteogenic differentiation ability, in vivo osteogenesis, and osteointegration ability after implantation in rat femurs among the Zn-5RE alloys, indicating promising potential in load-bearing biodegradable internal bone-fixation applications.


Assuntos
Implantes Absorvíveis , Ligas , Teste de Materiais , Osteogênese , Zinco , Animais , Ligas/química , Ligas/farmacologia , Corrosão , Zinco/química , Zinco/farmacologia , Osteogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Resistência à Tração , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Masculino , Diferenciação Celular/efeitos dos fármacos , Camundongos
7.
Heliyon ; 10(11): e31605, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38882370

RESUMO

Objective: The present study aimed to see if 20-Deoxyingenol(20-DOI) could protect hippocampus neurons from the neurotoxic effects of morphine and reduce memory loss in rats. Method: Male Wistar rats were given morphine hydrochloride (45 mg/kg, sc, four weeks) and 20-DOI (10, 20 mg/kg, ip., coadministered with morphine) for the Morris Water Maze (MWM) test to investigate the effects of 20-DOI on spatial learning and memory. Western blotting was used to evaluate the expression of the hippocampal CA1 region of the cleaved caspase-3, Bax, and Bcl2 proteins and so on. Moreover, these assays were used to evaluate the expression of superoxide dismutase (SOD)2, heme oxygenase 1(HO1) protein, and glutathione peroxidase (GPx) activity within the hippocampus CA1 area. Results: The administration of 20-DOI (10 and 20 mg/kg) to morphine-treated mice enhanced spatial learning and reduced memory deficits. Additionally, 20-DOI treatment reduced apoptosis and oxidative stress in the hippocampal CA1 region of morphine-treated rats. Moreover, 20-DOI improved the autophagy level of the hippocampal CA1 area of morphine-treated rats using Transcription factor EB (TFEB), and 20-DOI prevented spatial learning and memory impairment in morphine-treated rats. The current observation could be partially due to the inhibition of neuronal apoptosis and oxidative stress in the hippocampal CA1 region of rats treated with morphine and the improved autophagy in this region. Conclusions: 20-DOI attenuated morphine administration in rats with chronic disease caused spatial learning and memory dysfunction. These mechanistic effects could be partially related to 20-DOI protecting the CA1 region of rat hippocampal neurons from the morphine-induced oxidative stress, apoptosis, and autophagy through TFEB.

8.
Adv Mater ; 36(35): e2408067, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923636

RESUMO

Sn metal is a preferable choice as anode material for aqueous acidic batteries due to its acid-tolerance, non-toxicity, and ease of recycling. However, the large size and irregular deposition morphology of polyhedral Sn particles are bad for constructing stable and high-capacity Sn metal anode because of severe hydrogen evolution and metal shedding. To tackle this critical issue, 4-tert-octylphenol pentaethoxylate (POPE) is used as an electrolyte additive to generate a thin-film Sn anode with reversible stripping/plating behavior. POPE can not only induce homogeneous surface chemistry by adsorbing on the Sn surface via coordination bonds but also inhibit hydrogen evolution by modulating the solvation shell of Sn2+. The Sn film anode delivers improved electrochemical stability over 480 h with satisfactory rate performance and low polarization. Moreover, the as-assembled PbO2//Sn battery can also provide outstanding durability at 10 mAh cm-2. This work offers new inspiration for developing a reversible Sn metal film anode.

9.
Chemosphere ; 359: 142260, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735488

RESUMO

Human activity and industrial production have led to phenol becoming a significant risk factor. The proper treatment of phenol in wastewater is essential. In this study, the utilization of weak magnetic field (WMF) and zero-valent iron (ZVI) was proposed to activate H2O2 to degrade phenol contaminant. The results show that the weak magnetic field has greatly enhanced the reaction rate of ZVI/H2O2 removal of phenol. The removal rates of phenol by ZVI/H2O2/WMF generally decreased with increasing initial pH and phenol concentrations, and firstly increase and then decrease with increasing Fe0 or H2O2 dosage. When the initial pH is 5.0, ZVI concentration of 0.2 g L-1, H2O2 concentration of 6 mM, and phenol concentration of 100 mg L-1 were used, complete removal of phenol can be achieved within 180 min at 25 °C. The degradation process was consistent with the pseudo-first-order kinetic model when the experimental data was fitted. The ZVI/H2O2/WMF process exhibited a 1.05-2.66-fold enhancement in the removal rate of phenol under various conditions, surpassing its counterpart lacking WMF. It was noticed that the presence of 1-5 mM of Ca2+, Mg2+, Cl-, SO42- ions can significantly enhance the kinetics of phenol removal by ZVI/H2O2 system with or without WMF to 2.22-10.40-fold, but NO3-, CO32-, PO43- inhibited the reaction significantly in the following order: PO43- > CO32- > NO3-. Moreover, pre-magnetization for 3 min could enhance the ZVI/H2O2 process which was valuable in treatment of real wastewater. The hydroxyl radical has been identified as the primary radical species responsible for phenol degradation. The presence of WMF accelerates the corrosion rate of ZVI, thereby promoting the release of Fe2+ ions, which in turn induces an increased production of hydroxyl radicals and facilitates phenol degradation. The compounds hydroquinone, benzoquinone, catechol, maleic acid, and CO2 were identified using GC-MS, and degradation pathways were proposed. Employing WMF in combination with various ions like Ca2+, Mg2+, Cl-, SO42- is a novel method, which can enhance oxidation capacity of ZVI/H2O2 and may lead to economic benefit.


Assuntos
Peróxido de Hidrogênio , Ferro , Fenol , Águas Residuárias , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Fenol/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Ferro/química , Cinética , Campos Magnéticos , Íons/química , Concentração de Íons de Hidrogênio , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
11.
Chemosphere ; 357: 142037, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626811

RESUMO

In this study, a new catalyst for catalytic ozonation was obtained by in-situ growth of Mn-Ni3S2 nanosheets on the surface of nickel foam (NF). The full degradation of p-nitrophenol (PNP) was accomplished under optimal conditions in 40 min. The effects of material dosage, ozone dosage, pH and the presence of inorganic anions on the degradation efficiency of PNP were investigated. ESR analysis showed that singlet oxygen (1O2) and superoxide radical (O2•-) are the main contributors of PNP degradation. This study offers a new combination of supported catalysts with high efficiency and easy recovery, which provides a new idea for wastewater treatment.


Assuntos
Manganês , Níquel , Nitrofenóis , Ozônio , Poluentes Químicos da Água , Níquel/química , Nitrofenóis/química , Catálise , Ozônio/química , Manganês/química , Poluentes Químicos da Água/química , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos
13.
Plant Sci ; 341: 111999, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307350

RESUMO

Extracellular vesicles (EVs) are membrane-enclosed nanoparticles that have a crucial role in mediating intercellular communication in mammals by facilitating the transport of proteins and small RNAs. However, the study of plant EVs has been limited for a long time due to insufficient isolation and detection methods. Recent research has shown that both plants and plant pathogens can release EVs, which contain various bioactive molecules like proteins, metabolites, lipids, and small RNAs. These EVs play essential roles in plant-microbe interactions by transferring these bioactive molecules across different kingdoms. Additionally, it has been discovered that EVs may contribute to symbiotic communication between plants and pathogens. This review provides a comprehensive summary of the pivotal roles played by EVs in mediating interactions between plants and microbes, including pathogenic fungi, bacteria, viruses, and symbiotic pathogens. We highlight the potential of EVs in transferring immune signals between plant cells and facilitating the exchange of active substances between different species.


Assuntos
Vesículas Extracelulares , Animais , Vesículas Extracelulares/metabolismo , RNA , Comunicação Celular , Plantas , Simbiose , Mamíferos
14.
Molecules ; 29(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38338407

RESUMO

Novel bamboo activated carbon (BAC) catalysts decorated with manganese oxides (MnOx) were prepared with varying MnOx contents through a facile one-step redox reaction. Due to the physical anchoring effect of the natural macropore structure for catalyst active components, homogeneous MnOx nanoparticles (NPs), and high specific surface area over catalyst surface, the BAC@MnOx-N (N = 1, 2, 3, 4, 5) catalyst shows encouraging adsorption and catalytic oxidation for indoor formaldehyde (HCHO) removal at room temperature. Dynamic adsorption and catalytic activity experiments were conducted. The higher Smicro (733 m2/g) and Vmicro/Vt (82.6%) of the BAC@MnOx-4 catalyst could facilitate its excellent saturated and breakthrough adsorption capacity (5.24 ± 0.42 mg/g, 2.43 ± 0.22 mg/g). The best performer against 2 ppm HCHO is BAC@MnOx-4 catalyst, exhibiting a maximum HCHO removal efficiency of 97% for 17 h without any deactivation as RH = 0, which is higher than those of other MnOx-based catalysts. The average oxidation state and in situ DRIFTS analysis reveal that abundant oxygen vacancies on the BAC@MnOx-4 catalyst could be identified as surface-active sites of decomposing HCHO into the intermediate species (dioxymethylene and formate). This study provides a potential approach to deposit MnOx nanoparticles onto the BAC surface, and this hybrid BAC@MnOx material is promising for indoor HCHO removal at room temperature.

15.
Int J Biol Macromol ; 264(Pt 1): 130417, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417744

RESUMO

Cellulose-rich straws of corn and rice were torrefied under carbon dioxide, and the fuel characteristics and combustion performance of the obtained biochar were investigated. A high severity resulted in surface collapse, greater pore volume, elimination of oxygen, elevated calorific value, and improved hydrophobicity in biochar. Following carbon dioxide torrefaction, the cellulose content in solid biochar experienced a slight decrease when the temperature was raised to 220 °C for longer residence durations. At 300 °C, the cellulose content in the biochar was nearly eliminated, while the relative proportion of non-sugar organic matter in corn stover and rice straw increased to 87.40 % and 77.27 %, respectively. The maximum calorific values for biochar from corn and rice straws were 22.38 ± 0.03 MJ/kg and 18.72 ± 0.05 MJ/kg. The comprehensive combustion indexes of rice and corn straw samples decreased to 1.06 × 10-7 and 1.31 × 10-7 after torrefaction at 300 °C, respectively. In addition, the initial decomposition temperatures increased by 38 °C and 45 °C, while the ultimate combustion temperatures rose by 13 °C and 16 °C for corn and rice straws, respectively. These results imply an extended combustion timeframe for the torrefied samples.


Assuntos
Dióxido de Carbono , Celulose , Carvão Vegetal , Biomassa , Temperatura
16.
Int J Biol Macromol ; 262(Pt 2): 130205, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38365148

RESUMO

The degradation of lignin-carbohydrate complex (LCC) esters has been proven to be crucial for the selective separation of lignocellulosic components. This study utilized Raman microspectroscopy to image the preferential degradation of lignin and LCC esters from the bamboo wall during successive NaOH (0.2 to 5.0 % w/w), H2SO4 (1 to 8 % v/v), and NaClO2 (5 to 20 min) treatments. Raman imaging showed that lignin and LCC esters were selectively removed from the middle lamella of fibers and the secondary wall of parenchyma during NaOH and NaClO2 treatments. In contrast, H2SO4 primarily caused the simultaneous removal of lignin and LCC esters from the fiber wall under harsh conditions (8 %), while the middle lamella of parenchyma was less affected, both morphologically and topochemically. Raman spectral analysis indicated that the band intensity at 1605 cm-1 for lignin and at 1173 cm-1 for LCC esters decreased by >87.0 % in the highly lignified parenchyma secondary wall after a 5.0 % NaOH treatment, while the decrease was <67 % in the fiber wall. Interestingly, a strong linear correlation was observed between LCC esters and carbohydrates in the parenchyma (R2 > 0.912). These findings provide important insights into the graded and classified utilization of bamboo resources.


Assuntos
Ésteres , Lignina , Lignina/química , Hidróxido de Sódio , Carboidratos/química , Matriz Extracelular/metabolismo
17.
Environ Sci Pollut Res Int ; 30(58): 122393-122404, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37968488

RESUMO

MIL-101(Fe)/WS2 catalyst was composited using a solvothermal method. To study the physical and chemical properties of the composite material, a series of characterizations such as scanning electron microscope (SEM), X-ray diffraction (XRD), and catalytic experiments were carried out. The photocatalysis of the prepared catalyst in the degradation of tetracycline was investigated using persulfate (PS, Na2S2O8) as a cocatalyst under visible light illumination. The above system can remove about 80% of tetracycline within 40 min. After three cyclic experiments, the material showed good recycling. According to material characterization and various experimental results, the enhanced performance of the material was attributed to the reduction of the recombination efficiency of photogenerated e- and h+, and activated persulfate to produce a large number of free radicals such as O2•-, SO4•- and 1O2 produced by the active sites provided by the catalyst's high specific surface area.


Assuntos
Antibacterianos , Estruturas Metalorgânicas , Antibacterianos/química , Tetraciclina/química , Luz , Catálise
18.
Acta Biomater ; 169: 641-660, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37541605

RESUMO

Zinc (Zn) and its alloys are used in bone-fixation devices as biodegradable bone-implant materials due to their good biosafety, biological function, biodegradability, and formability. Unfortunately, the clinical application of pure Zn is hindered by its insufficient mechanical properties and slow degradation rate. In this study, a Zn-5 wt.% lanthanum (Zn-5La) alloy with enhanced mechanical properties, suitable degradation rate, and cytocompatibility was developed through La alloying and hot extrusion. The hot-extruded (HE) Zn-5La alloy showed ultimate tensile strength of 286.3 MPa, tensile yield strength of 139.7 MPa, elongation of 35.7%, compressive yield strength of 262.7 MPa, and microhardness of 109.7 HV. The corrosion resistance of the HE Zn-5La in Hanks' and Dulbecco's modified Eagle medium (DMEM) solutions gradually increased with prolonged immersion time. Further, the HE Zn-5La exhibited an electrochemical corrosion rate of 36.7 µm/y in Hanks' solution and 11.4 µm/y in DMEM solution, and a degradation rate of 49.5 µm/y in Hanks' solution and 30.3 µm/y in DMEM solution, after 30 d of immersion. The corrosion resistance of both HE Zn and Zn-5La in DMEM solution was higher than in Hanks' solution. The 25% concentration extract of the HE Zn-5La showed a cell viability of 106.5%, indicating no cytotoxicity toward MG-63 cells. We recommend the HE Zn-5La alloy as a promising candidate material for biodegradable bone-implant applications. STATEMENT OF SIGNIFICANCE: This work reports the mechanical properties, corrosion and degradation behaviors, in vitro cytocompatibility and antibacterial ability of biodegradable Zn-5La alloy for bone-implant applications. Our findings demonstrate that the hot-extruded (HE) Zn-5La alloy showed an ultimate tensile strength of 286.3 MPa, a yield strength of 139.7 MPa, an elongation of 35.7%, compressive yield strength of 262.7 MPa, and microhardness of 109.7 HV. HE Zn-5La exhibited appropriate degradation rates in Hanks' and DMEM solutions. Furthermore, the HE Zn-5La alloy showed good cytocompatibility toward MG-63 and MC3T3-E1 cells and greater antibacterial ability against S. aureus.


Assuntos
Ligas , Zinco , Teste de Materiais , Ligas/farmacologia , Ligas/química , Corrosão , Zinco/farmacologia , Zinco/química , Staphylococcus aureus , Implantes Absorvíveis , Antibacterianos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química
19.
Med Sci Monit ; 29: e939858, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37608539

RESUMO

BACKGROUND Patients experience severe pain in early postoperative rehabilitation after total knee arthroplasty (TKA). This study aimed to compare the effect of femoral nerve block with different concentrations of chloroprocaine on postoperative rehabilitation in patients with TKA. MATERIAL AND METHODS Ninety patients who only received unilateral TKA were randomly and equally divided into C1 (1% chloroprocaine 0.2 ml/kg), C2 (2% chloroprocaine 0.2 ml/kg), or NS (0.9% sodium chloride solution 0.2 ml/kg) groups. The patients received rehabilitation 3 times a day on days 3-6 after surgery, and femoral nerve block was performed with corresponding solution 10 min before each training session. We recorded the maximum knee flexion angles (MKFA) and maximum knee extension angles (MKEA) during active exercise on day 7 after surgery, as well as the incidence of MKFA ³100°, American knee society (AKS) scores, and postoperative rehabilitation satisfaction. Adverse effects after administration in each group were also recorded. RESULTS Compared with group NS, patients in group C1 and C2 had larger MKFA during active exercise on day 7 after TKA, and had better rehabilitation satisfaction (P<0.05). MKEA, the incidence of MKFA ≥100°, and AKS scores showed no significant differences in the 3 groups. There were more patients with decline of muscle strength in group C2 (P<0.05), and no other adverse reactions were recorded. CONCLUSIONS Chloroprocaine for femoral nerve block can be safely used in rehabilitation after TKA and to improve the knee flexion angle in the early postoperative period. Because they may have fewer adverse effects, 1% chloroprocaine 0.2 ml/kg may be preferred.


Assuntos
Artroplastia do Joelho , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Nervo Femoral , Procaína/uso terapêutico , Articulação do Joelho/cirurgia
20.
Biosensors (Basel) ; 13(7)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37504144

RESUMO

As a "gold standard biomarker", cardiac troponin I (cTnI) is widely used to diagnose acute myocardial infarction (AMI). For an early clinical diagnosis of AMI, it is necessary to develop a facile, fast and on-site device for cTnI detection. According to this demand, a point-of-care electrochemical aptasensor was developed for cTnI detection by coupling the advantages of screen-printed carbon electrode (SPCE) with those of an aptamer. Thiol and methylene blue (MB) co-labelled aptamer (MB-Apt-SH) was assembled on the surface of hierarchical flower-like gold nanostructure (HFGNs)-decorated SPCE (SPCE-HFGNs) to recognize and analyze cTnI. In the presence of cTnI, the specific biological recognition reaction between cTnI and aptamer caused the decrease in electrochemical signal. Under the optimal condition, this designed aptasensor showed wide linear range (10 pg/mL-100 ng/mL) and low detection limit for (8.46 pg/mL) for cTnI detection with high selectivity and stability. More importantly, we used a mobile phone coupled with a simple APP to efficiently detect cTnI in 10 µL 100% human serum samples, proving that this aptasensor has a promising potential in point-of-care testing.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Infarto do Miocárdio , Humanos , Limite de Detecção , Troponina I , Sistemas Automatizados de Assistência Junto ao Leito , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas , Carbono/química , Infarto do Miocárdio/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA