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1.
Molecules ; 29(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38338352

RESUMEN

Neurodegenerative diseases (NDDs) are mainly induced by oxidative stress which produces excessive reactive oxygen species (ROS). Quercetin (QU) is a potent antioxidant with some effects on NDDs. This study prepared and characterized a novel glucose-modified QU liposome (QU-Glu-Lip), aiming not only to overcome QU's poor water solubility and bioavailability but also to deliver more QU to brain tissue to enhance its neuroprotective effect. QU-Glu-Lip possessed encapsulation efficiency (EE) of 89.9%, homogenous particle sizes (116-124 nm), small PDI value (<0.3), zeta value -1.363 ± 0.437 mV, proper pH and salt stability, and proper cytotoxicity. The glucose-modified liposome penetrated the blood-brain barrier (BBB) mediated via the glucose transporter 1 (GLUT1) and was taken by neuronal cells more efficiently than liposome without glucose, according to bEnd.3 and PC12 cell tests. QU-Glu-Lip attenuated H2O2-induced oxidative damage to PC12 with higher cell viability (88.42%) and lower intracellular ROS compared to that of QU. QU-Glu-Lip had higher brain target ability and delivered more QU to neuronal cells, effectively exerting the antioxidative neuroprotection effect. There is potential for the QU-Glu-Lip application for more effective treatment of NDDs.


Asunto(s)
Antioxidantes , Quercetina , Antioxidantes/farmacología , Quercetina/farmacología , Liposomas , Peróxido de Hidrógeno , Neuroprotección , Especies Reactivas de Oxígeno , Glucosa , Encéfalo
2.
J Neurosci Res ; 98(2): 353-370, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31359506

RESUMEN

The relationships of digit ratio (2D:4D) with the length of AR (CAG)n, and testosterone levels from saliva and blood have been extensively debated over the years. This research including three studies further clarifies such controversies. To do so, we re-examined the relationships between the length of AR (CAG)n, 2D:4D, and current testosterone levels, through replication study and meta-analysis for each study. The results indicate: (a) the length of AR (CAG)n is not significantly associated with 2D:4D; (b) current testosterone levels are not significantly associated with the ratio; and (c) the length is not significantly associated with testosterone levels. Thus, AR (CAG)n and current testosterone levels are not significantly related to 2D:4D at individual level.


Asunto(s)
Dedos/anatomía & histología , Polimorfismo Genético , Receptores Androgénicos/genética , Testosterona/análisis , Femenino , Genotipo , Humanos , Masculino , Saliva/química , Adulto Joven
3.
Int J Mol Sci ; 20(11)2019 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-31181732

RESUMEN

Flexible transparent conductive films (FTCFs) composed of silver nanowires (AgNWs) have become an important research direction because of their potential in flexible electronic devices. The optoelectronic properties of FTCFs composed of AgNWs of different lengths were evaluated in this study. AgNWs, with an average diameter of about 25 nm and length of 15.49-3.92 µm were obtained by a sonication-induced scission process. AgNW-FTCFs were prepared on polyethylene terephthalate substrates using a Meyer bar and then dried in the ambient environment. The sheet resistance, non-uniformity factor of the sheet resistance, the root mean square roughness, and haze of the FTCFs increased as the length of AgNWs decreased. The transmittance of the films increased slightly as the length of AgNWs increased. AgNWs with a length of 15.49 µm provided an AgNW-FTCF with excellent properties including haze of 0.95%, transmittance of 93.42%, and sheet resistance of 80.15 Ω∙sq-1, without any additional post-treatment of the film. This work investigating the dependence of the optoelectronic properties of AgNW-FTCFs on AgNW length provides design guidelines for development of AgNW-FTCFs.


Asunto(s)
Nanopartículas del Metal/química , Nanocables/química , Plata/química , Conductividad Eléctrica , Fenómenos Ópticos , Tereftalatos Polietilenos/química , Sonicación
4.
Molecules ; 24(4)2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30813374

RESUMEN

Three new substituted bithiophenes (1⁻3), and one new sulf-polyacetylene ester, ritroyne A (16) were isolated from the whole plant of Echinops ritro together with twelve known substituted thiophenes. The structures were elucidated on the basis of extensive spectroscopic analysis including 1D and 2D NMR as well as MS. Furthermore, the absolute configuration of ritroyne A (16) was established by computational methods. In bioscreening experiments, four compounds (2, 4, 12, 14) showed similar antibacterial activity against Staphylococcus aureus ATCC 2592 with levofloxacin (8 µg/mL). Five compounds (2, 4, 9, 12, 14) exhibited antibacterial activities against Escherichia coli ATCC 25922, with minimum inhibitory concentration (MIC) values of 32⁻64 µg/mL. Three compounds (2, 4, 12) exhibited antifungal activities against Candida albicans ATCC 2002 with MIC values of 32⁻64 µg/mL. However, compound 16 did not exhibit antimicrobial activities against three microorganisms.


Asunto(s)
Echinops (Planta)/química , Polímero Poliacetilénico/química , Polímero Poliacetilénico/farmacología , Tiofenos/química , Tiofenos/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Staphylococcus aureus/efectos de los fármacos
5.
Chemistry ; 24(28): 7235-7242, 2018 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-29508450

RESUMEN

Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is an innovative molecular imaging technique in which contrast agents are labeled by saturating their exchangeable proton spins by radio-frequency irradiation. Salicylic acid and its analogues are a promising class of highly sensitive, diamagnetic CEST agents. Herein, polymeric agents grafted with salicylic acid moieties and a known high-affinity ligand targeting prostate-specific membrane antigen in approximately 10:1 molar ratio were synthesized to provide sufficient MRI sensitivity and receptor specificity. The proton-exchange properties of the contrast agent in solution and in an experimental murine model are reported to demonstrate the feasibility of receptor-targeted CEST MRI of prostate cancer. Furthermore, the CEST imaging data were validated with an 111 In-labeled analogue of the agent by in vivo single photon emission computed tomographic imaging and tissue biodistribution studies.


Asunto(s)
Medios de Contraste/química , Polímeros/química , Neoplasias de la Próstata/diagnóstico por imagen , Ácido Salicílico/química , Animales , Humanos , Imagen por Resonancia Magnética , Masculino , Protones , Distribución Tisular
6.
Sci Total Environ ; 939: 173516, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-38802011

RESUMEN

Over the past decades, the accumulation of plastics in mangrove ecosystems has emerged as a significant environmental concern, primarily due to anthropogenic activities. Polypropylene (PP) films, one of the plastic types with the highest detection rate, tend to undergo intricate aging processes in mangrove ecosystems, leading to the release of dissolved organic matter (DOM) that may further influence the local bacterial communities. Yet, the specific effects of new and weathered (aged) plastic films and the associated leached DOM on bacterial consortia in mangrove sediments remain poorly understood. In this study, an incubation experiment was conducted to elucidate the immediate effects and mechanisms of the new and relatively short-term (45 or 90 days) aged PP films, as well as their leached DOM (PDOM), on characteristics of DOM and the bacterial community structure in mangrove sediments under different tidal conditions. Surface morphology and functional group analyses showed that both new and aged PP films exhibited comparable degradation profiles under different tidal conditions over the incubation period. As compared to the new PP film treatments, the introduction of the short-term aged PP films significantly affected the content of humic-like compounds in sediments, and such effects were partially ascribed to the release of PDOM during the incubation. Although the addition of PP films and PDOM showed minor effects on the overall diversity and composition of bacterial communities in the sediments, the abundance of some dominant phyla exhibited a growth or reduction tendency, possibly changing their ecological functions. This study was an effective attempt to investigate the relationship among plastic surface characteristics, sedimentary physicochemical properties, and bacterial communities in mangrove sediments. It revealed the ecological ramifications of new and short-term plastic pollution and its leachates in mangrove seedtimes, enhancing our understating of their potential impacts on the health of mangrove ecosystems.


Asunto(s)
Bacterias , Sedimentos Geológicos , Polipropilenos , Humedales , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiología , Contaminantes Químicos del Agua/análisis , Microbiota
7.
Acta Biomater ; 179: 220-233, 2024 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-38554890

RESUMEN

An effective treatment for the irregular partial-thickness cartilage defect in the early stages of osteoarthritis (OA) is lacking. Cartilage tissue engineering is effective for treating full-thickness cartilage defects with limited area. In this study, we designed an injectable multifunctional poly(lactic-co-glycolic acid) (PLGA) microsphere to repair partial-thickness cartilage defects. The microsphere was grafted with an E7 peptide after loading the microsphere with kartogenin (KGN) and modifying the outer layer through dopamine self-polymerization. The microsphere could adhere to the cartilage defect, recruit synovial mesenchymal stem cells (SMSCs) in situ, and stimulate their differentiation into chondrocytes after injection into the articular cavity. Through in vivo and in vitro experiments, we demonstrated the ability of multifunctional microspheres to adhere to cartilage matrix, recruit SMSCs, and promote their differentiation into cartilage. Following treatment, the cartilage surface of the model group with partial-thickness cartilage defect showed smooth recovery, and the glycosaminoglycan content remained normal; the untreated control group showed significant progression of OA. The microsphere, a framework for cartilage tissue engineering, promoted the expression of SMSCs involved in cartilage repair while adapting to cell migration and growth. Thus, for treating partial-thickness cartilage defects in OA, this innovative carrier system based on stem cell therapy can potentially improve therapeutic outcomes. STATEMENT OF SIGNIFICANCE: Mesenchymal stem cells (MSCs) therapy is effective in the repair of cartilage injury. However, because of the particularity of partial-thickness cartilage injury, it is difficult to recruit enough seed cells in situ, and there is a lack of suitable scaffolds for cell migration and growth. Here, we developed polydopamine surface-modified PLGA microspheres (PMS) containing KGN and E7 peptides. The adhesion ability of the microspheres is facilitated by the polydopamine layer wrapped in them; thus, the microspheres can adhere to the injured cartilage and recruit MSCs, thereby promoting their differentiation into chondrocytes and accomplishing cartilage repair. The multifunctional microspheres can be used as a safe and potential method to treat partial-thickness cartilage defects in OA.


Asunto(s)
Anilidas , Células Madre Mesenquimatosas , Microesferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Animales , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Conejos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Diferenciación Celular/efectos de los fármacos , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacología , Cartílago Articular/patología , Ácido Poliglicólico/química , Ácido Láctico/química , Inyecciones , Matriz Extracelular/metabolismo , Condrocitos/citología , Condrocitos/metabolismo , Ingeniería de Tejidos/métodos
8.
Adv Healthc Mater ; 13(3): e2302327, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37947298

RESUMEN

Stem cell tissue engineering is a potential treatment for osteoarthritis. However, the number of stem cells that can be delivered, loss of stem cells during injection, and migration ability of stem cells limit applications of traditional stem cell tissue engineering. Herein, kartogenin (KGN)-loaded poly(lactic-co-glycolic acid) (PLGA) porous microspheres is first engineered via emulsification, and then anchored with chitosan through the amidation reaction to develop a new porous microsphere (PLGA-CS@KGN) as a stem cell expansion vector. Following 3D co-culture of the PLGA-CS@KGN carrier with mesenchymal stem cells (MSCs), the delivery system is injected into the capsule cavity in situ. In vivo and in vitro experiments show that PLGA-CS microspheres have a high cell-carrying capacity up to 1 × 104 mm-3 and provide effective protection of MSCs to promote their controlled release in the osteoarthritis microenvironment. Simultaneously, KGN loaded inside the microspheres effectively cooperated with PLGA-CS to induce MSCs to differentiate into chondrocytes. Overall, these findings indicate that PLGA-CS@KGN microspheres held high cell-loading ability, adapt to the migration and expansion of cells, and promote MSCs to express markers associated with cartilage repair. Thus, PLGA-CS@KGN can be used as a potential stem cell carrier for enhancing stem cell therapy in osteoarthritis treatment.


Asunto(s)
Cartílago Articular , Osteoartritis , Humanos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Microesferas , Ácido Poliglicólico , Ácido Láctico , Porosidad , Conservación de los Recursos Naturales , Regeneración , Células Madre , Osteoartritis/terapia
9.
Int J Biol Macromol ; 272(Pt 2): 132830, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38825264

RESUMEN

Artificial graft serves as the primary grafts used in the clinical management of sports-related injuries. Until now, optimizing its graft-host integration remains a great challenge due to the excessive inflammatory response during the inflammatory phase, coupled with an absence of tissue-inductive capacity during the regeneration phase. Here, a multi-layered regenerated silk fibroin (RSF) coating loaded with curcumin (Cur) and Zn2+ on the surface of the PET grafts (Cur@Zn2+@PET) was designed and fabricated for providing time-matched regulation specifically tailored to address issues arising at both inflammatory and regeneration phases, respectively. The release of Cur and Zn2+ from the Cur@Zn2+@PET followed a time-programmed pattern in vitro. Specifically, cellular assays revealed that Cur@Zn2+@PET initially released Cur during the inflammatory phase, thereby markedly inhibit the expression of inflammatory cytokines TNF-a and IL-1ß. Meanwhile, a significant release of Zn2+ was major part during the regeneration phase, serving to induce the osteogenic differentiation of rBMSC. Furthermore, rat model of anterior cruciate ligament reconstruction (ACLR) showed that through time-programmed drug release, Cur@Zn2+@PET could suppress the formation of fibrous interface (FI) caused by inflammatory response, combined with significant new bone (NB) formation during regeneration phase. Consequently, the implementation of the Cur@Zn2+@PET characterized by its time-programmed release patterns hold considerable promise for improving graft-host integration for sports-related injuries.


Asunto(s)
Curcumina , Fibroínas , Zinc , Curcumina/farmacología , Curcumina/química , Animales , Zinc/química , Zinc/farmacología , Ratas , Fibroínas/química , Fibroínas/farmacología , Liberación de Fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Masculino , Osteogénesis/efectos de los fármacos , Ratas Sprague-Dawley
10.
Viruses ; 16(6)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38932262

RESUMEN

Hepatitis A virus (HAV), a member of the genus Hepatovirus (Picornaviridae HepV), remains a significant viral pathogen, frequently causing enterically transmitted hepatitis worldwide. In this study, we conducted an epidemiological survey of HepVs carried by small terrestrial mammals in the wild in Yunnan Province, China. Utilizing HepV-specific broad-spectrum RT-PCR, next-generation sequencing (NGS), and QNome nanopore sequencing (QNS) techniques, we identified and characterized two novel HepVs provisionally named EpMa-HAV and EpLe-HAV, discovered in the long-tailed mountain shrew (Episoriculus macrurus) and long-tailed brown-toothed shrew (Episoriculus leucops), respectively. Our sequence and phylogenetic analyses of EpMa-HAV and EpLe-HAV indicated that they belong to the species Hepatovirus I (HepV-I) clade II, also known as the Chinese shrew HepV clade. Notably, the codon usage bias pattern of novel shrew HepVs is consistent with that of previously identified Chinese shrew HepV. Furthermore, our structural analysis demonstrated that shrew HepVs differ from other mammalian HepVs in RNA secondary structure and exhibit variances in key protein sites. Overall, the discovery of two novel HepVs in shrews expands the host range of HepV and underscores the existence of genetically diverse animal homologs of human HAV within the genus HepV.


Asunto(s)
Genoma Viral , Filogenia , Musarañas , Animales , Musarañas/virología , China/epidemiología , ARN Viral/genética , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Infecciones por Picornaviridae/veterinaria , Infecciones por Picornaviridae/virología , Infecciones por Picornaviridae/epidemiología
11.
Cladistics ; 29(2): 147-165, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34814378

RESUMEN

The relationships of extant and extinct lineages of Adephaga were analysed formally for the first time. Emphasis is placed on the aquatic and semiaquatic groups and their evolution in the Mesozoic. †Triadogyrus and †Mesodineutus belong to Gyrinidae, the sister group of the remaining families. †Triaplidae are the sister group of the following groups (Haliplidae, Geadephaga, Dytiscoidea incl. †Liadytidae, †Parahygrobiidae and †Coptoclavidae [major part]). The lack of a ventral procoxal joint and a very short prosternal process are plesiomorphies of †Triaplidae. †Coptoclavidae and †Timarchopsinae are paraphyletic. †Timarchopsis is placed in a geadephagan clade. In contrast to other coptoclavids, its metathorax is close to the condition found in Haliplidae, with a complete transverse ridge and coxae with large plates and free mesal walls. †Coptoclavidae s.str., i.e. excl. †Timarchopsis, is a dytiscoid subgroup. The mesal metacoxal walls are fused, the coxal plates are reduced, and the transverse ridge is absent. †Stygeonectes belongs to this dytiscoid coptoclavid unit and is therefore misplaced in †Timarchopsinae. †Liadytidae belongs to a dytiscoid subgroup, which also comprises the extant families Aspidytidae, Amphizoidae, Hygrobiidae and Dytiscidae. †Parahygrobia is the sister group of Hygrobiidae. The larvae are characterized by a broad gula, the absence of the lacinia, retractile maxillary bases and very long urogomphi set with long setae. †Liadytiscinae is the sister group of extant Dytiscidae. There is no support for a clade †Eodromeinae and for Trachypachidae incl. †Eodromeinae. †Fortiseode is nested within Carabidae. The exclusion of fossil taxa has no effect on the branching pattern. The evolution of Adephaga in the Mesozoic is discussed. Possible reasons for the extinction of †Coptoclavidae are the rise of teleost fish and the competition of Gyrinidae and Dytiscidae, which possess efficient defensive glands and larval mandibular sucking channels.

12.
Drug Dev Ind Pharm ; 39(1): 67-76, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22339718

RESUMEN

The objective of present work was to design and evaluate gliclazide push-pull osmotic pump (PPOP) coated with aqueous colloidal polymer dispersions-Eudragit(®) RL 30D and Eudragit(®) RS 30D. The influence of diacetin, diethyl phthalate (DEP), dibutyl sebacate (DBS) and triethyl citrate (TEC) on the free Eudragit(®) RL 30D and Eudragit(®) RS 30D films as plasticizers on drug release were studied. Among these four plasticizers, diacetin offered the smoothest surface of the cast films, and it displayed greatest water vapor transmission coefficient. Free RL and RS films with diacetin also exhibited greatest erosion compared with the other three plasticizers. On the other hand, TEC, DEP and DBS showed greater water absorption. When compared with CA-coated gliclazide PPOP, Eudragit-coated ones showed a f(2) factor of 71.7, indicating the similarity between the release profile of the two formulations. The prepared Eudragit-coated gliclazide PPOP showed typical Zero-order release characteristics, with R being 0.9953. In the in vivo evaluation, the mean relative oral bioavailability of Eudragit-coated PPOP compared to CA-coated ones was 106.9%, demonstrating good bioequivalence. Both of their in vitro-in vivo correlation (IVIVC) showed linear relationship, with R(2) being 0.9955 (Eudragit-coated PPOP) and 0.9987 (CA-coated PPOP), respectively. These results suggested that PPOP coated with Eudragit(®) RL 30D and RS 30D could overcome drawbacks of organic solution coating and promote the development of PPOP.


Asunto(s)
Gliclazida/administración & dosificación , Hipoglucemiantes/administración & dosificación , Ácidos Polimetacrílicos/administración & dosificación , Resinas Acrílicas/administración & dosificación , Resinas Acrílicas/farmacocinética , Animales , Preparaciones de Acción Retardada , Perros , Sistemas de Liberación de Medicamentos/métodos , Gliclazida/farmacocinética , Hipoglucemiantes/farmacocinética , Ósmosis , Presión Osmótica , Polímeros , Ácidos Polimetacrílicos/farmacocinética , Solubilidad
13.
Am J Orthod Dentofacial Orthop ; 142(6): 879-87, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23195374

RESUMEN

INTRODUCTION: The aims of this study were to determine the accuracy of volumetric measurements of teeth in vitro by cone-beam computed tomography (CBCT) and to analyze the factors affecting their volume measurements from the CBCT data. METHODS: We used a sample of CBCT-scanned (voxel sizes: 0.125, 0.20, 0.25, 0.30, and 0.40 mm) and laser-scanned crowns (n = 40) and roots (n = 32). The Tukey test was used to assess the differences between the CBCT-scan and the laser-scan volumes. RESULTS: There was a statistically significant difference between the laser-scan crown volume and each voxel size of CBCT-scan crown volume (P <0.05). CBCT-scan crown volumes at 0.30 and 0.40 mm were statistically significantly distinct from those at 0.125, 0.20, and 0.25 mm (P <0.05). There was a statistically significant difference between the laser-scan root volume and each voxel size of CBCT-scan root volume (P <0.05). The laser-scan root volume at 0.40 mm was statistically significantly distinct from the volumes at 0.125 and 0.20 mm (P <0.05). The in-vitro volume measurements from the CBCT scans were larger than those of the laser scans: from 21.73% to 43.92% in the crown halves, and from 18.27% to 41.58% in the root halves at the different voxel sizes. CONCLUSIONS: With increasing voxel sizes during scanning, the volume measurements of teeth tended to be larger. The surface surrounding artifacts might lead to larger volumes.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Radiografía Dental/métodos , Humanos , Rayos Láser , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Corona del Diente/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen
14.
Leg Med (Tokyo) ; 54: 101996, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34864482

RESUMEN

Transverse fracture of the skull base is common both in the crushing of temporal regions of the skull and in the case of force acting on one temporal region. However, the mechanism of transverse skull base fracture caused by maxillofacial force has not been fully clarified. To provide an injury identification basis for forensic pathologists and clinicians, this paper combines accident reconstruction and finite element analysis methods to study the injury mechanism of an incomplete transverse fracture of skull base after the injured individual's mandible was subjected to violence in a traffic accident. The results show that after the injured individual's mandible was subjected to violence, forces in the direction of the left mandibular fossa and the right mandibular fossa were generated, creating the component forces. The combination of the two forces can produce a crushing effect toward the center of the skull base, as if the left and right temporal regions are being crushed, and the stress is concentrated at the joint of the mandible, the middle cranial fossa and the hypophyseal fossa. When the stress exceeds a certain limit, it will cause a transverse fracture of the skull base.


Asunto(s)
Fracturas Óseas , Fracturas Craneales , Análisis de Elementos Finitos , Humanos , Mandíbula , Base del Cráneo
15.
Chemosphere ; 292: 133389, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34953878

RESUMEN

Sustainable management of low fertile arid soils using carbon-rich organic amendments such as biochar and compost is of great concern from both agricultural and environmental points of view. The impact of pyrolysis, composting, and co-composting processes of different feedstocks on carbon loss and emissions, soil properties, and plant growth in arid soils with low organic matter content has not been sufficiently explored yet. Consequently, the aim of this work was to 1) investigate the effects of the pyrolysis, composting, and co-composting processes on the properties of the produced biochar, compost, and co-composted biochar from rice straw (RS) and sugarcane bagasse (SB), and 2) examine the impact of addition of RB biochar (RSB), SB biochar (SBB), RS compost (RSC), SB compost (SBC), co-composted RS biochar (RSCB), and co-composted SB biochar (SBCB) at an application dose of 10 ton/hectare on soil properties, carbon emission, and growth of zucchini (Cucurbita pepo) in a sandy arid soil. Carbon loss (kg C kg-1 feedstock) was significantly (P < 0.05) lower during the preparation of the compost (90.36 in RSC, 220.00 in SBC) and co-composted-biochar (146.35 in RSCB, 125.20 in SBCB) than in biochar (176.5 in RSB, 305.6 in SBB). The C/N ratios of the compost and co-composted biochar (11-28.5) were narrower than the corresponding values of biochars (48-90). All amendments increased significantly soil organic carbon content (2.5 in RSC to 5.5 g kg-1 in RSCB), as compared to the non-amended control (1.2 g kg-1). All amendments, particularly RSCB, increased significantly (P < 0.05) the zucchini seed vigor index, dry weight, total chlorophyll content, and root and shoot length, as compared to the control. Moreover, RSCB was the only amendment that showed a positive soil carbon balance. The modified integrated two-way ecological model data also indicated that the co-composted biochar, particularly RSCB, is a promising amendment to improve soil quality and plant growth in sandy arid soils. However, those data should be verified under field conditions.


Asunto(s)
Compostaje , Oryza , Saccharum , Carbono , Celulosa , Carbón Orgánico , Arena , Suelo
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(1): 115-120, 2021 Feb 01.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-33723947

RESUMEN

Many patients with large-area tooth defect need cast post-core crown restoration. However, the color defect of the cast post-core will affect the final restorative result, especially that of the anterior teeth. A new technology of color masking by applying CERAMAGE polymeric porcelain to the cast metal post-core surface improves the color of a full-ceramic restoration of anterior teeth and may provide a new alternative for the aesthetic repair of anterior teeth with a large area of defective tooth.


Asunto(s)
Porcelana Dental , Técnica de Perno Muñón , Cerámica , Coronas , Estética Dental , Humanos
17.
Chem Commun (Camb) ; 56(48): 6579-6582, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32400773

RESUMEN

An intracellular signal amplification strategy was developed for the quantification of ATP in single cells by microchip electrophoresis with laser-induced fluorescence detection. By using the method proposed, intracellular ATP levels in single HeLa, HepG2 and HL-7702 cells were found to be in the range of 30-150, 30-140, and 19-120 fmol per cell, respectively.


Asunto(s)
Adenosina Trifosfato/análisis , Electroforesis por Microchip/métodos , Rayos Láser , Adenosina Trifosfato/metabolismo , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Línea Celular Tumoral , Luciferina de Luciérnaga/química , Humanos , Liposomas/química , Microscopía Confocal , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia
18.
Sci Total Environ ; 710: 136289, 2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-31923667

RESUMEN

In this work, nanoscale zero-valent iron (NZVI) was synthesized via liquid phase reduction method with surfactant polyethylene glycol (PEG-4000) modified and supported onto zeolite to prepare PZ-NZVI composite. SEM-EDS, XPS, BET.etc. characterizations indicated that the sphere NZVI particles were loaded on the zeolite successfully and the aggregation was restrained. The adsorption performance of PZ-NZVI for norfloxacin (NOR) or ofloxacin (OFL), two typical fluoroquinolones (FQs), from water was conducted. The equilibrium studies were demonstrated using Langmuir, Freundlich, Temkin and Elovich isotherms and better agreement was attained with the Temkin model. Compared with NZVI and zeolite, PZ-NZVI had higher FQs removal efficiency, and the Langmuir maximum adsorption capacity was 54.67 mg g-1 (NOR) and 48.88 mg g-1 (OFL). The kinetic parameters displayed that two FQs adsorption onto PZ-NZVI followed pseudo-second-order kinetic model. The thermodynamic analysis suggested the adsorption process was spontaneous and exothermic. In addition, the adsorption tests were executed at different influence factors and the adsorbent PZ-NZVI was suitable for a wide pH range (4-10) with the FQs (10 mg L-1) removal efficiency above 90% in 1 h. Furthermore, it was found that PZ-NZVI can be effortlessly separated from mixed solutions using external magnetic field. Finally, the process of FQs adsorbed onto PZ-NZVI was attributed to the surface complexion (forming bidentate complexes), hydrophobic interaction, pore filling and electrostatic interaction.


Asunto(s)
Zeolitas/química , Adsorción , Antibacterianos , Fluoroquinolonas , Hierro , Polietilenglicoles , Contaminantes Químicos del Agua
19.
Artif Cells Nanomed Biotechnol ; 47(1): 2838-2845, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31307228

RESUMEN

Although titanium implants account for a large proportion of the commercial dental market, their bioactivity are inadequate in many applications. A micro- and nano- scale hierarchical surface topography of the implant is suggested for rapid osseointegration from the biomimetic perspective. Moreover, Zinc (Zn) is an essential element in the skeletal system. Thus, a micro/nanostructured TiO2/ZnO coating, produced by micro-arc oxidation, and hydrothermal treatment, and heat treatment, was designed to endow the implant surface with enhanced osteogenic capacity. Physiochemical properties and biological effects of this coating were investigated in our study. The annealed micro/nanostructured TiO2/ZnO coating exhibited higher hydrophilicity and fibronectin adsorption ability compared to the micro-arc oxidation modified TiO2 coating. SaOS-2 cells grown on the annealed micro/nanostructured TiO2/ZnO coating showed increased alkaline phosphatase activity and collagen secretion, and immunofluorescence labeling revealed an upregulation of osteopontin, collagen type ι and osteocalcin. The micro/nanostructure and incorporation of Zn were considered to perform positive effect on the enhanced osteogenic activity of SaOS-2 cells. In conclusion, the micro/nanostructured TiO2/ZnO structure is simple, stable, and easy to produce and scale up, has promising applications in the surface modification of titanium implants.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Nanoestructuras/química , Osteogénesis/efectos de los fármacos , Titanio/química , Óxido de Zinc/química , Adsorción , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Fibronectinas/química , Humanos , Humectabilidad
20.
Yao Xue Xue Bao ; 43(9): 963-8, 2008 Sep.
Artículo en Zh | MEDLINE | ID: mdl-19048791

RESUMEN

A novel mucoadhesive microcapsule with drug-resin complex core loaded with berberine hydrochloride (BH) was developed and optimized. Drug-ion exchange resin (IER) complex was prepared by static method which stirring IER in drug solution at certain conditions. The influences of different IERs, different temperature, pH values and concentrations of drug solution on the drug loading were investigated. IER complex was coated by emulsion-solvent evaporation method. The coating fluid formulation was optimized using central composite design-response surface methodology, where the ratio between Carbopol 934 and IER (X1), the ratio between Eudragit and IER (X2) and the ratio between Eudragit RL and RS (X3) were taken as independent variables. Time of cumulative release 85% (Y1) and percentage of gastric retention (Y2) were taken as response variables. Drug loading achieved a high level and more drug available in the condition of IER (IRP 88), 37 degrees C, pH 5 and 1.0 mg x mL(-1) drug solution. When X1 = 0.75, X2 = 0.9, X3 = 0.6, the time of cumulative release reached 85% at 300 min, the highest percentage of gastric retention in the range of this experiment were procured.


Asunto(s)
Berberina/administración & dosificación , Berberina/farmacocinética , Sistemas de Liberación de Medicamentos , Mucosa Gástrica/metabolismo , Resinas de Intercambio Iónico/química , Acrilatos/química , Animales , Cápsulas , Preparaciones de Acción Retardada , Composición de Medicamentos/métodos , Emulsiones , Concentración de Iones de Hidrógeno , Masculino , Polímeros/química , Ratas , Ratas Sprague-Dawley , Temperatura
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