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1.
Proc Natl Acad Sci U S A ; 120(5): e2210651120, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36689664

RESUMEN

Millions of years of evolution have allowed animals to develop unusual locomotion capabilities. A striking example is the legless-jumping of click beetles and trap-jaw ants, which jump more than 10 times their body length. Their delicate musculoskeletal system amplifies their muscles' power. It is challenging to engineer insect-scale jumpers that use onboard actuators for both elastic energy storage and power amplification. Typical jumpers require a combination of at least two actuator mechanisms for elastic energy storage and jump triggering, leading to complex designs having many parts. Here, we report the new concept of dynamic buckling cascading, in which a single unidirectional actuation stroke drives an elastic beam through a sequence of energy-storing buckling modes automatically followed by spontaneous impulsive snapping at a critical triggering threshold. Integrating this cascade in a robot enables jumping with unidirectional muscles and power amplification (JUMPA). These JUMPA systems use a single lightweight mechanism for energy storage and release with a mass of 1.6 g and 2 cm length and jump up to 0.9 m, 40 times their body length. They jump repeatedly by reengaging the latch and using coiled artificial muscles to restore elastic energy. The robots reach their performance limits guided by theoretical analysis of snap-through and momentum exchange during ground collision. These jumpers reach the energy densities typical of the best macroscale jumping robots, while also matching the rapid escape times of jumping insects, thus demonstrating the path toward future applications including proximity sensing, inspection, and search and rescue.


Asunto(s)
Hormigas , Escarabajos , Robótica , Animales , Locomoción/fisiología , Músculos , Fenómenos Biomecánicos
2.
Invest New Drugs ; 41(6): 825-833, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37837490

RESUMEN

BACKGROUND: Anlotinib plus chemotherapy as first-line treatment for extensive-stage small-cell lung cancer (ES-SCLC) achieves good efficacy, but there is still room for improvement. This clinical study examined the effectiveness of anlotinib plus etoposide for maintenance therapy in ES-SCLC. METHODS: The current single-arm, prospective phase II study was performed at Jiangsu Cancer Hospital (March 2019 to March 2022). After successful primary etoposide-based therapy, anlotinib was administered at 12 mg/day on days 1 to 14 of 21-day cycles until disease progression or consent withdrawal. All patients also received etoposide at 50 mg/day on days 1 to 14 of 21-day cycles for a maximum of six cycles. Progression-free survival (PFS) constituted the primary study endpoint. Secondary endpoints were overall survival (OS), objective remission rate (ORR), disease control rate (DCR), and safety. In addition, adverse events (AEs) were assessed. RESULTS: Twenty-eight patients were treated. Median PFS and OS were 8.02 (95%CI 5.36-10.67) and 11.04 (95%CI 10.37-11.68) months, respectively. Totally 9 and 18 participants showed a partial response and stable disease, respectively; ORR and DCR were 32.14% and 96.43%, respectively. The commonest all-grade AEs were fatigue (n = 11, 39.28%), hypertension (n = 11, 39.28%), loss of appetite (n = 9, 32.14%), oral mucositis (n = 7, 25.00%) and proteinuria (n = 6, 21.40%). Grade 3-4 AEs included fatigue (n = 4, 14.28%), hypertension (n = 2, 7.14%), hand and foot syndrome (n = 2, 7.14%), oral mucositis (n = 1, 3.57%), hemoptysis (n = 1, 3.57%), proteinuria (n = 1, 3.57%), gingival bleeding (n = 1, 3.57%), and serum creatinine elevation (n = 1, 3.57%). CONCLUSION: Maintenance anlotinib plus etoposide achieves promising PFS and OS in clinical ES-SCLC. REGISTRATION NUMBER: ChiCTR1800019421.


Asunto(s)
Hipertensión , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Estomatitis , Humanos , Etopósido/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Estudios Prospectivos , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Hipertensión/inducido químicamente , Proteinuria/inducido químicamente , Estomatitis/inducido químicamente
3.
BMC Oral Health ; 23(1): 28, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36650491

RESUMEN

BACKGROUND: It is difficult for orthodontists to accurately predict the growth trend of the mandible in children with anterior crossbite. This study aims to develop a deep learning model to automatically predict the mandibular growth result into normal or overdeveloped using cephalometric radiographs. METHODS: A deep convolutional neural network (CNN) model was constructed based on the algorithm ResNet50 and trained on the basis of 256 cephalometric radiographs. The prediction behavior of the model was tested on 40 cephalograms and visualized by equipped with Grad-CAM. The prediction performance of the CNN model was compared with that of three junior orthodontists. RESULTS: The deep-learning model showed a good prediction accuracy about 85%, much higher when compared with the 54.2% of the junior orthodontists. The sensitivity and specificity of the model was 0.95 and 0.75 respectively, higher than that of the junior orthodontists (0.62 and 0.47 respectively). The area under the curve value of the deep-learning model was 0.9775. Visual inspection showed that the model mainly focused on the characteristics of special regions including chin, lower edge of the mandible, incisor teeth, airway and condyle to conduct the prediction. CONCLUSIONS: The deep-learning CNN model could predict the growth trend of the mandible in anterior crossbite children with relatively high accuracy using cephalometric images. The deep learning model made the prediction decision mainly by identifying the characteristics of the regions of chin, lower edge of the mandible, incisor teeth area, airway and condyle in cephalometric images.


Asunto(s)
Aprendizaje Profundo , Maloclusión , Humanos , Niño , Mandíbula/diagnóstico por imagen , Redes Neurales de la Computación , Radiografía , Maloclusión/diagnóstico por imagen
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(1): 112-119, 2022 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-35231972

RESUMEN

Liposomes with precisely controlled composition are usually used as membrane model systems to investigate the fundamental interactions of membrane components under well-defined conditions. Hydration method is the most common method for liposome formation which is found to be influenced by composition of the medium. In this paper, the effects of small alcohol (ethanol) on the hydration of lipid molecules and the formation of liposomes were investigated, as well as its coexistence with sodium chloride. It was found that ethanol showed the opposite effect to that of sodium chloride on the hydration of lipid molecules and the formation of liposomes. The presence of ethanol promoted the formation of liposomes within a certain range of ethanol content, but that of sodium chloride suppressed the liposome formation. By investigating the fluorescence intensity and continuity of the swelled membranes as a function of contents of ethanol and sodium chloride, it was found that sodium chloride and ethanol showed the additive effect on the hydration of lipid molecules when they coexisted in the medium. The results may provide some reference for the efficient preparation of liposomes.


Asunto(s)
Etanol , Liposomas , Etanol/farmacología , Lípidos
5.
Arch Virol ; 164(11): 2811-2817, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31471723

RESUMEN

Rabies remains a public health threat in China, and most transmissions are dog-mediated. In this study, we studied 31 clinically diagnosed human rabies patients that had been scratched or bitten by dogs. Real-time reverse transcription polymerase chain reaction (RT-qPCR) and nested RT-PCR were performed on saliva samples or cerebrospinal fluid, and samples from 28 patients tested positive for rabies virus. A total of one near-complete genome sequence, 15 complete glycoprotein (G) gene sequences, and five partial G gene sequences were determined. Phylogenetic analysis was performed, based on complete G gene sequences, using the maximum-likelihood method. The results indicated that the isolates belonged to the lyssavirus genotype I lineage and China I lineage. The Chinese rabies virus can be divided into six major lineages. The China I lineage was the dominant clade and could be divided into four subclades. Isolates 17HN19, 17HN75, and 18HN162 fell within clade IC subgroup, and the other isolates were assigned to the clade IA subgroup. This study provides epidemiological and genetic information on rabies incidence in humans.


Asunto(s)
Líquido Cefalorraquídeo/virología , Virus de la Rabia/clasificación , Virus de la Rabia/genética , Rabia/epidemiología , Saliva/virología , Adolescente , Adulto , Anciano , Animales , Niño , China/epidemiología , Enfermedades de los Perros/virología , Perros , Femenino , Genoma Viral/genética , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Rabia/virología , Virus de la Rabia/aislamiento & purificación , Adulto Joven
6.
Waste Manag ; 185: 43-54, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38820783

RESUMEN

Plastics within municipal solid waste (MSW) are non-degradable. As MSW continues to degrade, the relative content of plastics rises, and particle gradation may also change. Moreover, throughout the landfilling process, MSW is subjected to various stress conditions, potentially influencing its mechanical properties. This study explored the effects of varying plastic contents, different particle gradations, and distinct stress paths on the mechanical properties of MSW, and consolidated drained triaxial tests of 42 groups of reconstituted MSW specimens were conducted. The results showed that there was an optimal plastic content of 6-9 % for MSW, where the shear strength of MSW was higher than that of MSW with other plastic contents. When the stress path changed from TC45 to TC72, the optimal plastic content of MSW changed from 6 % to 9 %. As the plastic content increased, both the cohesion and internal friction angle of the MSW initially increased, then subsequently decreased. The impact of plastic content on cohesion was more pronounced than on the internal friction angle, especially at larger strains. Under various stress paths, MSW with distinct particle size distributions demonstrated diverse stress-strain behaviors. Traditional criteria for evaluating well-graded conditions in soils are not suitable for MSW. The effect of gradation on the cohesion of MSW is essentially due to the predominant role of fiber content; the relationship between gradation and the internal friction angle in MSW is complex and correlates closely with the content of both coarse and fine particles, as well as fibers. This study serves as an essential reference for predicting deformations in landfills and analyzing the stability of landfill slopes.


Asunto(s)
Plásticos , Eliminación de Residuos , Residuos Sólidos , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Estrés Mecánico , Tamaño de la Partícula , Resistencia al Corte , Instalaciones de Eliminación de Residuos
7.
Microbiol Res ; 280: 127575, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38147744

RESUMEN

Synergistic microbial co-culture has been an efficient and energy-saving strategy to produce lignin-degrading enzymes (LDEs), including laccase, manganese peroxidase, and versatile peroxidase. However, the regulatory mechanism of microbial co-culture is still unclear. Herein, the extracellular LDE activities of four white-rot fungi were significantly increased by 88-544% over monoculture levels when co-cultured with Rhodotorula mucilaginosa. Ptf6 was demonstrated from the 9 million Y1H clone library to be a shared GATA transcription factor in the four fungi, and could directly bind to the laccase gene promoter. Ptf6 exists in two alternatively spliced isoforms under monoculture, namely Ptf6-α (1078 amino acids) containing Cys2/Cys2-type zinc finger and Ptf6-ß (963 amino acids) lacking the complete domain. Ptf6 responded to co-culture by up-regulation of both its own transcripts and the proportion of Ptf6-α. Ptf6-α positively activated the production of most LDE isoenzymes and bound to four GATA motifs on the LDEs' promoter with different affinities. Moreover, Ptf6-regulation mechanism can be applicable to a variety of microbial co-culture systems. This study lays a theoretical foundation for further improving LDEs production and providing an efficient way to enhance the effects of biological and enzymatic pretreatment for lignocellulosic biomass conversion.


Asunto(s)
Lacasa , Lignina , Lignina/metabolismo , Lacasa/genética , Factores de Transcripción/genética , Técnicas de Cocultivo , Aminoácidos
8.
J Hazard Mater ; 471: 134343, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640671

RESUMEN

Microplastics are a growing concern in mangrove ecosystems; however, their effects on archaeal communities and related ecological processes remain unclear. We conducted in situ biofilm-enrichment experiments to investigate the ecological influence of polyethylene (PE) and polypropylene microplastics on archaeal communities in the sediments of mangrove ecosystems. The archaeal community present on microplastics was distinct from that of the surrounding sediments at an early stage but became increasingly similar over time. Bathyarchaeota, Thaumarchaeota, Euryarchaeota, and Asgardaeota were the most abundant phyla. Methanolobus, an archaeal biomarker, was enriched in PE biofilms, and significantly controlled by homogeneous selection in the plastisphere, indicating an increased potential risk of methane emission. The dominant archaeal assembly process in the sediments was deterministic (58.85%-70.47%), while that of the PE biofilm changed from stochastic to deterministic during the experiment. The network of PE plastispheres showed less complexity and competitive links, and higher modularity and stability than that of sediments. Functional prediction showed an increase in aerobic ammonia oxidation during the experiment, whereas methanogenesis and chemoheterotrophy were significantly higher in the plastisphere. This study provides novel insights into the impact of microplastic pollution on archaeal communities and their mediating ecological functions in mangrove ecosystems.


Asunto(s)
Archaea , Biopelículas , Sedimentos Geológicos , Microplásticos , Polietileno , Polipropilenos , Humedales , Archaea/efectos de los fármacos , Archaea/metabolismo , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Microplásticos/toxicidad , Biopelículas/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Ecosistema
9.
Adv Mater ; 36(4): e2304364, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37885340

RESUMEN

Self-assembling peptides are valuable building blocks to fabricate supramolecular biomaterials, which have broad applications from biomedicine to biotechnology. However, limited choices to induce different globular proteins into hydrogels hinder these designs. Here, an easy-to-implement and tunable self-assembling strategy, which employs Ure2 amyloidogenic peptide, are described to induce any target proteins to assemble into supramolecular hydrogels alone or in combination with notable compositional control. Furthermore, the collective effect of nanoscale interactions among amyloid nanofibrils and partially disordered elastomeric polypeptides are investigated. This led to many useful macroscopic material properties simultaneously emerging from one pure protein material, i.e. strong adhesion to any substrates under wet conditions, rapidly self--assembling into robust and porous hydrogels, adaptation to remodeling processes, strongly promoting cell adhesion, proliferation and differentiation. Moreover, he demonstrated this supramolecular material's robust performance in vitro and vivo for tissue engineering, cosmetic and hemostasis applications and exhibited superior performance compared to corresponding commercial counterparts. To the best of his knowledge, few pure protein-based materials could meet such seemingly mutually exclusive properties simultaneously. Such versatility renders this novel supramolecular nanomaterial as next-generation functional protein-based materials, and he demonstrated the sequence level modulation of structural order and disorder as an untapped principle to design new proteins.


Asunto(s)
Proteínas Amiloidogénicas , Proteínas de Insectos , Nanoestructuras , Péptidos/química , Nanoestructuras/química , Amiloide/química , Materiales Biocompatibles/química , Hidrogeles/química
10.
Acta Biomater ; 158: 239-251, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36581005

RESUMEN

Abdominal adhesions are a class of serious complications following abdominal surgery, resulting in a complicated and severe syndrome and sometimes leading to a Gordian knot. Traditional therapies employ hydrogels synthesized using complicated chemical formulations-often with click chemistry or thermal responsive hydrogel. The complicated synthesis process and severe conditions limit the extent of the hydrogels' applications. In this work, poly 3-[2-(methacryloyloxy)ethyl](dimethyl)-ammonio]-1-propanesulfonate (PSBMA) polymer was synthesized to self-assemble into physical hydrogels due to the inter- and intramolecular ion interactions. The strong static interaction bonding density has a substantial impact on the gelation and physicochemical properties, which is beneficial to clinical applications and offers a novel way to obtain the desired hydrogel for a specific biomedical application. Intriguingly, this PSBMA polymer can be customized into a transient network with outstanding antifouling capability depending on the ion concentration. As ion concentration increases, the PSBMA hydrogel dissociated completely, endowing it as a candidate for adhesion prevention. In the cecum-sidewall model, the PSBMA hydrogel demonstrated superior anti-adhesion properties than commercial HA hydrogel. Furthermore, we have demonstrated that this PSBMA hydrogel could inhibit the inflammatory response and encourage anti-fibrosis resulting in adhesion prevention. Most surprisingly, the recovered skins of cecum and sidewall are as smooth as the control skin without any scar and damage. In conclusion, a practical hydrogel was synthesized using a facile method based on purely zwitterionic materials, and this ion-sensitive, antifouling adjustable supramolecular hydrogel with great clinic transform potential is a promising barrier for preventing postoperative tissue adhesion. STATEMENT OF SIGNIFICANCE: The development of hydrogels with satisfactory coverage, long retention time, facile synthetic method, and good biocompatibility is vital for preventing peritoneal adhesions. Herein, we developed a salt sensitive purely zwitterionic physical hydrogel poly 3-[2-(methacryloyloxy)ethyl](dimethyl)-ammonio]-1-propanesulfonate (PSBMA) hydrogel to effectively prevent postoperative and recurrent abdominal adhesions. The hydrogel was simple to synthesize and easy to use. In the cecum-sidewall model, PSBMA hydrogel could instantaneously adhere and fix on irregular surfaces and stay in the wound for more than 10 days. The PSBMA hydrogel could inhibit the inflammatory response, encourage anti-fibrosis, and restore smoothness to damaged surfaces resulting in adhesion prevention. Overall, the PSBMA hydrogel is a promising candidate for the next generation of anti-adhesion materials to meet clinical needs.


Asunto(s)
Ácidos Alcanesulfónicos , Hidrogeles , Humanos , Hidrogeles/farmacología , Hidrogeles/química , Adherencias Tisulares/prevención & control , Polímeros
11.
Front Pediatr ; 10: 911591, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783299

RESUMEN

Aims: We employed machine-learning methods to explore data from a large survey on students, with the goal of identifying and validating a thrifty panel of important factors associated with lower respiratory tract infection (LRTI). Methods: Cross-sectional cluster sampling was performed for a survey of students aged 6-14 years who attended primary or junior high school in Beijing within January, 2022. Data were collected via electronic questionnaires. Statistical analyses were completed using the PyCharm (Edition 2018.1 x64) and Python (Version 3.7.6). Results: Data from 11,308 students (5,527 girls and 5,781 boys) were analyzed, and 909 of them had LRTI with the prevalence of 8.01%. After a comprehensive evaluation, the Gaussian naive Bayes (gNB) algorithm outperformed the other machine-learning algorithms. The gNB algorithm had accuracy of 0.856, precision of 0.140, recall of 0.165, F1 score of 0.151, and area under the receiver operating characteristic curve (AUROC) of 0.652. Using the optimal gNB algorithm, top five important factors, including age, rhinitis, sitting time, dental caries, and food or drug allergy, had decent prediction performance. In addition, the top five factors had prediction performance comparable to all factors modeled. For example, under the sequential deep-learning model, the accuracy and loss were separately gauged at 92.26 and 25.62% when incorporating the top five factors, and 92.22 and 25.52% when incorporating all factors. Conclusions: Our findings showed the top five important factors modeled by gNB algorithm can sufficiently represent all involved factors in predicting LRTI risk among Chinese students aged 6-14 years.

12.
J Environ Public Health ; 2022: 9379135, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36046076

RESUMEN

A prefabricated concrete structure is a building structure designed for sustainability and low comprehensive carbon emission. The grouted sleeve splice is a major connection method for prefabricated concrete structures. However, construction defects occur easily in the grouted sleeve splice connection at construction sites because of complex construction environments and the high connection accuracy. To determine the influence of rebar in steel half-grouted sleeve connections with construction defects, investigations were conducted using four different test groups (rebar offset, rebar bended, insufficient fluidity of grout, and control group). The load-displacement curve and load-stress curve were analyzed on 24 different specimens through uniaxial tension experiments. The experimental results showed that rebar fracture was the failure of specimens. The load-displacement curves consisted of elastic, yield, strength, and tight stages. The curves were similar to rebar under uniaxial tension, except for the rebar bended group. The axial stress and circumferential stress on the sleeve surface consistently followed a linear response before the specimen yield, whereas the axial stress and circumferential stress showed a rebound response after the specimen yielded. Different finite element models were established based on the different defects. Compared with the experimental results, the finite element analysis results coincided with those of the experimental results, and the errors were within 8% to evaluate the performance of steel half-grouted sleeve connections in construction.


Asunto(s)
Ambiente , Acero
13.
BMC Med Genomics ; 15(1): 161, 2022 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-35842615

RESUMEN

BACKGROUND: Hypophosphatemic rickets (HR) is a rare genetic disorder associated with renal phosphate wasting and characterized by bone defects. Inactivating mutations in the phosphate regulating endopeptidase homolog X­linked gene (PHEX) account for most cases of HR. The aim of this study was to identify causative variants in nine unrelated Chinese families associated with HR, and to determine potential pathogenicity of the identified variants. METHODS: Genomic DNA was isolated from the peripheral blood of HR patients and their healthy relatives, followed by next-generation sequencing and/or Sanger sequencing. In silico prediction combined with conservation analysis was performed to assess the effects of the variants, and 3D protein modeling was conducted to predict the functional effects on the encoded protein. RESULTS: All HR patients recruited in this study displayed bone deformities and tooth agenesis, as well as reduced serum phosphate levels and elevated urine phosphate levels. Nine PHEX variants were identified in eight families, including four novel variants (c.1661_1726del, c.980A > G, c.1078A > T, and c.1017_1051dup). Of the nine identified PHEX variants, five caused a truncated protein, two caused an altered amino acid, and the other two were the canonical splicing variants. Novel variants c.1336G > A and c.1364 T > C in SLC34A3 were also found in one family. Conservation analysis showed that all the amino acids corresponding to the missense variants were highly conserved. In silico analysis and 3D protein structure modeling confirmed the pathogenicity of these variants. CONCLUSIONS: This study identified four novel variants in PHEX and two novel variants in SLC34A3 in a Chinese cohort with HR. Our findings highlight the dominant role of PHEX in HR, and expand the genotypic and phenotypic spectra of this disorder.


Asunto(s)
Raquitismo Hipofosfatémico Familiar , Raquitismo Hipofosfatémico , China , Raquitismo Hipofosfatémico Familiar/genética , Humanos , Mutación , Endopeptidasa Neutra Reguladora de Fosfato PHEX/genética , Linaje , Fosfatos , Raquitismo Hipofosfatémico/genética
14.
Colloids Surf B Biointerfaces ; 218: 112798, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36030726

RESUMEN

Magnesium (Mg) alloys are potential materials for orthopedic fixation devices but rapid degradation of the materials restricts wider clinical applications. Herein, zinc-incorporated calcium phosphate (Ca-Zn-P) coatings are prepared on the Zn-pretreated WE43 Mg alloy by a hydrothermal technique under relatively stable and favorable conditions. The hydrothermal coating consists of a compact bottom layer of CaZn2(PO4)2∙2 H2O and ZnO granular crystals and a jagged upper layer of CaHPO4. The Zn coating reduces the corrosion current density of WE43 to (3.49 ± 1.60) × 10-5 A cm-2, whereas the Ca-Zn-P/Zn composite coating further reduces it by 3 orders of magnitude in the simulated body fluid (SBF). The charge transfer resistances of the Zn-coated and Ca-Zn-P/Zn-coated alloys increase by 49 and 7176 times to 835 and 1.22 × 105 Ω cm2, respectively. The 7-day immersion results reveal that the Zn coating cannot provide long-term protection to WE43 in SBF because of the formation of galvanic couples between the Zn coating and WE43. In contrast, Ca-Zn-P/Zn-coated WE43 remains intact after soaking for 7 days and furthermore, the Ca-Zn-P coating self-repairs and continues to grow despite dissolution. The compact and adherent Ca-Zn-P bottom layer plays a major role in mitigating corrosion of WE43 by hindering penetration of the aggressive medium and charge transfer of the corrosion reactions resulting in only slight corrosion of the Zn layer. Biologically, the Zn coating reduces attachment and proliferation of MC3T3-E1 pre-osteoblasts on WE43, but the composite coating fosters cell adhesion and proliferation which stems from the good biocompatibility of the hydrothermal layer and relatively stable surface conditions avoiding severe corrosion.


Asunto(s)
Magnesio , Óxido de Zinc , Aleaciones/química , Aleaciones/farmacología , Fosfatos de Calcio , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Corrosión , Magnesio/química , Magnesio/farmacología , Ensayo de Materiales , Zinc/química , Zinc/farmacología
15.
Environ Int ; 151: 106439, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33626455

RESUMEN

This study focused on the effect of algae on the fouling potential and dynamic fouling variation of foulants in an innovative algal-sludge membrane bioreactor (AS-MBR). Filtration experiments revealed that the soluble extracellular polymeric substance (S-EPS) released by the algal-sludge flocs showed a slower diminishing rate of flux than that released by the sludge flocs. The intermediate blocking and cake filtration models demonstrated the major mechanisms, which implied a reduction in the driving force of pore blocking and fouling layer formation induced by the algal-bacterial S-EPS. Furthermore, the relative flux decrements of loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) in the AS-MBR were lower than those of the control without algae, indicating a reduction in the fouling potential of the bound EPS (B-EPS) in the algal-sludge flocs compared to the control. This could be attributed to the reduction in the membrane intercepts for LB- and TB-EPS, respectively. Specifically, S-EPS and B-EPS released by algal-sludge flocs had a lower free energy of cohesion (ΔGcoh) than those released by sludge flocs (decreased of 19.14%, 45.93%, and 43.34% for the S-EPS, LB-EPS, and TB-EPS, respectively). Furthermore, these changes could contribute to the decrease in the relative abundance of adsorbed polysaccharide- and protein-like substances in the B-EPS (released by algal-sludge flocs) filtration membrane, leading to the formation of less rough peaks and valleys in the fouling layer in the AS-MBR. Accordingly, the lower fouling propensity and weaker cohesion energy of S-EPS and B-EPS tend to decrease the hydrophobicity and the free energy of the floc surface and further provide less driving force to adhere to the membrane, resulting in significant mitigation of membrane fouling in the AS-MBR. Therefore, the overall fouling behavior caused by S-EPS, B-EPS and flocs should be comprehensively considered to achieve an underlying understanding of the algal effect on membrane fouling control.


Asunto(s)
Matriz Extracelular de Sustancias Poliméricas , Aguas del Alcantarillado , Reactores Biológicos , Filtración , Membranas Artificiales
16.
Mitochondrial DNA B Resour ; 6(4): 1308-1309, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33855184

RESUMEN

We determined a complete mitochondrial genome of Episoriculus leucops. This mitogenome is a circular molecule with 16,838 bp in length, containing 13 protein-coding genes, 22 transfer RNA genes (tRNA), and two ribosomal RNA genes (rRNA). This mitochondrial genome has a base composition of 32.8% A, 29.2% T, 24.9% C, and 13.1% G. We reconstructed Bayesian phylogenetic tree by taking advantage of 19 species belonging to subfamily Soricinae. Phylogenetic tree shows that the long-tailed red-toothed shrew belongs to genus Episoriculus, and it is the closest relationship with E. caudatus. This mitochondrial genome provides an important resource for addressing taxonomic issues and studying molecular evolution.

17.
ACS Appl Mater Interfaces ; 13(15): 17207-17219, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33845570

RESUMEN

Osteoclastic resorption of bones plays a central role in both osteoporosis and bone metastasis. A reliable in vitro assay that simulates osteoclastic resorption in vivo would significantly speed up the process of developing effective therapeutic solutions for those diseases. Here, we reported the development of a novel and robust nanostructured calcium phosphate coating with unique functions on the track-etched porous membrane by using an ammonia-induced mineralization (AiM) technique. The calcium phosphate coating uniformly covers one side of the PET membrane, enabling testing for osteoclastic resorption. The track-etched pores in the PET membrane allow calcium phosphate mineral pins to grow inside, which, on the one hand, enhances coating integration with a membrane substrate and, on the other hand, provides diffusion channels for delivering drugs from the lower chamber of a double-chamber cell culture system. The applications of the processed calcium phosphate coating were first demonstrated as a drug screening device by using alendronate, a widely used drug for osteoporosis. It was confirmed that the delivery of alendronate significantly decreased both the number of monocyte-differentiated osteoclasts and coating resorption. To demonstrate the application in studying bone metastasis, we delivered a PC3 prostate cancer-conditioned medium and confirmed that both the differentiation of monocytes into osteoclasts and the osteoclastic resorption of the calcium phosphate coating were significantly enhanced. This novel assay thus provides a new platform for studying osteoclastic activities and assessing drug efficacy in vitro.


Asunto(s)
Amoníaco/química , Huesos/patología , Fosfatos de Calcio/química , Nanoestructuras/química , Osteoporosis/fisiopatología , Alendronato/administración & dosificación , Alendronato/farmacología , Animales , Huesos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Portadores de Fármacos/química , Humanos , Membranas Artificiales , Ratones , Osteoclastos/efectos de los fármacos , Osteoclastos/patología , Osteoporosis/metabolismo , Osteoporosis/patología , Células PC-3 , Porosidad , Células RAW 264.7
18.
Appl Biochem Biotechnol ; 193(7): 2087-2097, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33599948

RESUMEN

A combined severity factor (RCSF) which is usually used to evaluate the effectiveness of hydrothermal pretreatment at above 100 °C had been developed to assess the influence of temperature, time, and alkali loading on pretreatment and enzymatic hydrolysis of lignocellulose. It is not suitable for evaluating alkaline pretreatment effectiveness at lower than 100 °C. According to the reported deducing process, this study modified the expression of [Formula: see text] as [Formula: see text] which is easier and more reasonable to assess the effectiveness of alkaline pretreatment. It showed that RCSF exhibited linear trend with lignin removal, and quadratic curve relation with enzymatic hydrolysis efficiency (EHE) at the same temperature. The EHE of alkali-treated SCB could attain the maximum value at lower RCSF, which indicated that it was not necessary to continuously enhance strength of alkaline pretreatment for improving EHE. Within a certain temperature range, the alkali loading was more important than temperature and time to influence pretreatment effectiveness and EHE. Furthermore, the contribution of temperature, time, and alkali loading to pretreatment cost which was seldom concerned was investigated in this work. The alkali loading contributed more than 70% to the pretreatment cost. This study laid the foundation of further optimizing alkaline pretreatment to reduce cost for its practical application.


Asunto(s)
Celulasa/química , Celulosa/química , Saccharum/química , Hidróxido de Sodio/química , Hidrólisis
19.
Mater Sci Eng C Mater Biol Appl ; 110: 110688, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32204117

RESUMEN

HYPOTHESIS: Osseointegration can be enhanced by introducing bioactive polyelectrolyte-multilayer films on implant surfaces. To guarantee films to function successfully in use, keeping structural integrity during implanting is necessary, which requires films with strong adhesion and cohesion to resist the mechanical damage. Catechol is considered as the origin of amazing adhesion of mussels. We hypothesize that catechol functionalization of polyelectrolytes enables film construction on implants in a non-aggressive way, and helps films resist mechanical damages during implanting. EXPERIMENTS: With lipopolysaccharide-amine nanopolymersomes (NPs), catechol-functionalized hyaluronic acid and NPs (cHA, cNPs) as a polycation, polyanion and primer, respectively, catechol-functionalized polyelectrolyte-multilayer films (cPEMs) were constructed on substrates via Layer-by-layer self-assembly. Effects of catechol functionalization on construction, surface properties, assembly mechanisms, structural integrity, mechanical properties and cytotoxicity of cPEMs were studied. FINDINGS: Self-adhesive cPEMs can be constructed on substrates, which grow exponentially and are driven by coordination, covalent bonding, electrostatic interactions, hydrogen bonding, etc. cPEMs with suitable catechol concentrations can resist mechanical damage to keep structural integrity in simulated clinical implantation, show stronger adhesion and cohesion than non-catechol-functionalized films in nanoscratch and nanoindentation tests, and are non-cytotoxic to MSCs. With excellent drug-loading and cytosolic-delivery capacity of NPs, cPEM is promising in improving osseointegration of implants.


Asunto(s)
Adhesivos/química , Titanio/química , Animales , Catecoles/química , Células Cultivadas , Implantes Dentales , Ácido Hialurónico/química , Nanopartículas/química , Oseointegración/efectos de los fármacos , Polielectrolitos/química , Polímeros/química , Prótesis e Implantes , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie/efectos de los fármacos
20.
J Biomed Mater Res B Appl Biomater ; 108(4): 1213-1228, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31423745

RESUMEN

Increasing cases of adverse local tissue reactions (ALTRs) associated with metal release have been observed in patients with metal-on-highly crosslinked polyethylene (MoP) hip implants, the most common design in total hip replacements. Studies have demonstrated the metal release from fretting corrosion at the head-neck junction, but rarely investigated tribocorrosion associated metal release at articulating surfaces in MoP hip implants. The objective of this study is to investigate both tribocorrosion at the articulating surfaces and fretting corrosion at the head-neck junction in CoCrMo femoral heads, as well as their association with metal species released in periprosthetic tissues and body fluids in MoP hip systems. Twenty-three patients with ALTRs associated with MoP implants were included. Systematic analyses were performed on the wear damage in articulation, corrosion at the head-neck junction and their correlation with degradation products observed in synovial fluid, periprosthetic tissues, and serum. Results showed that tribocorrosion at the articulating surfaces contributed to the elevated concentration of both Co and Cr ions in serum, while fretting corrosion at the head-neck junction mainly released Co ions to serum. Both tribocorrosion at the articulating surfaces and fretting corrosion at the head-neck junction released particles rich in chromium and phosphate, the dominant particles found in synovial fluids and tissues. This study provides strong evidence that tribocorrosion at the articulating surfaces in MoP hip implants could result in significant metal release. This information should be taken into account when studying the mechanisms of ALTRs and developing strategies of preventing metal release in total hip replacements.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Análisis de Falla de Equipo , Prótesis de Cadera/efectos adversos , Polietileno/química , Falla de Prótesis , Vitalio/química , Adulto , Anciano , Anciano de 80 o más Años , Corrosión , Femenino , Humanos , Masculino , Persona de Mediana Edad
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