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1.
J Nanobiotechnology ; 22(1): 560, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39272197

RESUMO

Intravesical therapy (IT) is widely used to tackle various urological diseases. However, its clinical efficacy is decreased by the impermeability of various barriers presented on the bladder luminal surface, including the urinary mucus layer and the densely packed tissue barrier. In this study, we report a mucoadhesive-to-penetrating nanomotors-in-hydrogel system for urothelium-oriented intravesical drug delivery. Upon intravesical instillation, its poloxamer 407 (PLX) hydrogel gelated and adhered to the urothelium to prolong its intravesical retention. The urea afterwards diffused into the hydrogel, thus generating a concentration gradient. Urease-powered membrane nanomotors (UMN) without asymmetric surface engineering could catalyze the urea and migrate down this concentration gradient to deeply and unidirectionally penetrate the urothelial barrier. Moreover, the intravesical hybrid system-delivered gemcitabine could effectively inhibit the bladder tumor growth without inducing any side effect. Therefore, our mucoadhesive-to-penetrating nanomotors-in-hydrogel system could serve as an alternative to IT to meet the clinical need for more efficacious therapeutics for urological diseases.


Assuntos
Sistemas de Liberação de Medicamentos , Hidrogéis , Poloxâmero , Neoplasias da Bexiga Urinária , Urotélio , Urotélio/metabolismo , Animais , Hidrogéis/química , Sistemas de Liberação de Medicamentos/métodos , Administração Intravesical , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Camundongos , Poloxâmero/química , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/administração & dosagem , Gencitabina , Bexiga Urinária/metabolismo , Humanos , Feminino , Linhagem Celular Tumoral , Adesividade
2.
BMC Plant Biol ; 23(1): 501, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37848871

RESUMO

BACKGROUND: The cotton industry suffers significant yield losses annually due to Verticillium wilt, which is considered the most destructive disease affecting the crop. However, the precise mechanisms behind this disease in cotton remain largely unexplored. METHODS: Our approach involved utilizing transcriptome data from G. australe which was exposed to Verticillium dahliae infection. From this data, we identified ethylene-responsive factors and further investigated their potential role in resistance through functional validations via Virus-induced gene silencing (VIGS) in cotton and overexpression in Arabidopsis. RESULTS: A total of 23 ethylene response factors (ERFs) were identified and their expression was analyzed at different time intervals (24 h, 48 h, and 72 h post-inoculation). Among them, GauERF105 was selected based on qRT-PCR expression analysis for further investigation. To demonstrate the significance of GauERF105, VIGS was utilized, revealing that suppressing GauERF105 leads to more severe infections in cotton plants compared to the wild-type. Additionally, the silenced plants exhibited reduced lignin deposition in the stems compared to the WT plants, indicating that the silencing of GauERF105 also impacts lignin content. The overexpression of GauERF105 in Arabidopsis confirmed its pivotal role in conferring resistance against Verticillium dahliae infection. Our results suggest that WT possesses higher levels of the oxidative stress markers MDA and H2O2 as compared to the overexpressed lines. In contrast, the activities of the antioxidant enzymes SOD and POD were higher in the overexpressed lines compared to the WT. Furthermore, DAB and trypan staining of the overexpressed lines suggested a greater impact of the disease in the wild-type compared to the transgenic lines. CONCLUSIONS: Our findings provide confirmation that GauERF105 is a crucial candidate in the defense mechanism of cotton against Verticillium dahliae invasion, and plays a pivotal role in this process. These results have the potential to facilitate the development of germplasm resistance in cotton.


Assuntos
Arabidopsis , Ascomicetos , Verticillium , Gossypium/genética , Gossypium/metabolismo , Arabidopsis/genética , Lignina/metabolismo , Peróxido de Hidrogênio/metabolismo , Verticillium/fisiologia , Ascomicetos/metabolismo , Etilenos , Resistência à Doença/genética , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
3.
Small ; 19(11): e2207278, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36651002

RESUMO

Drug delivery nanoparticles (NPs) based entirely on materials generally recognized as safe that provide widespread parenchymal distribution following intracranial administration via convection-enhanced delivery (CED) are introduced. Poly(lactic-co-glycolic acid) (PLGA) NPs are coated with various poloxamers, including F68, F98, or F127, via physical adsorption to render particle surfaces non-adhesive, thereby resisting interactions with brain extracellular matrix. F127-coated PLGA (F127/PLGA) NPs provide markedly greater distribution in healthy rat brains compared to uncoated NPs and widespread coverage in orthotopically-established brain tumors. Distribution analysis of variously-sized F127/PLGA NPs determines the average rat brain tissue porosity to be between 135 and 170 nm while revealing unprecedented brain coverage of larger F127/PLGA NPs with an aid of hydraulic pressure provided by CED. Importantly, F127/PLGA NPs can be lyophilized for long-term storage without compromising their ability to penetrate the brain tissue. Further, 65- and 200-nm F127/PLGA NPs lyophilized-reconstituted and administered in a moderately hyperosmolar infusate solution show further enhance particle dissemination in the brain via osmotically-driven enlargement of the brain tissue porosity. Combination of F127/PLGA NPs and osmotic tissue modulation provides a means with a clear regulatory path to maximize the brain distribution of large NPs that enable greater drug loading and prolong drug release.


Assuntos
Nanopartículas , Neoplasias , Ratos , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico , Ácido Láctico , Portadores de Fármacos , Encéfalo , Tamanho da Partícula
4.
Fish Shellfish Immunol ; 134: 108577, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36773712

RESUMO

Strongylocentrotus intermedius is one of the most economically valuable sea urchin species in China and has experienced mass mortality owing to outbreaks of bacterial diseases such as black mouth disease. This has caused serious economic losses to the sea urchin farming industry. To investigate the immune response mechanism of S. intermedius with different tube feet colors in response to Vibrio harveyi infection, we examined the different tube feet-colored S. intermedius under V. harveyi challenge and compared their transcriptome and microRNA (miRNA) profiles using RNA-Seq. We obtained 1813 differentially expressed genes (DEGs), 28 DE miRNAs, and 303 DE miRNA-DEG pairs in different tube feet-colored S. intermedius under V. harveyi challenge. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the most significant DEGs were associated with the Notch signaling and phagosome pathways. The target genes of immune-related miRNAs (miR-71, miR-184, miR-193) and genes (CALM1, SPSB4, DMBT, CSRP1) in S. intermedius were predicted and validated. This study provides insight into the molecular mechanisms that regulate genes involved in the immune response of S. intermedius infected with V. harveyi.


Assuntos
MicroRNAs , Strongylocentrotus , Vibrioses , Animais , RNA Mensageiro , Transcriptoma , Imunidade Inata/genética
5.
Environ Res ; 231(Pt 3): 116244, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245567

RESUMO

The production and use of organophosphate esters (OPEs) as substitutes for traditional halogenated flame retardants is increasing, resulting in greater global concern related to their ecological risks to marine environments. In this study, polychlorinated biphenyls (PCBs) and OPEs, representing traditional halogenated and emerging flame retardants, respectively, were studied in multiple environmental matrices in the Beibu Gulf, a typical semi-closed bay in the South China Sea. We investigated the differences in PCB and OPE distributions, sources, risks, and bioremediation potentials. Overall, the concentrations of emerging OPEs were much higher than those of PCBs in both seawater and sediment samples. Sediment samples from the inner bay and bay mouth areas (L sites) accumulated more PCBs, with penta- and hexa-CBs as major homologs. Chlorinated OPEs were prevalent in both seawater and sediment samples from the L sites, whereas tri-phenyl phosphate (TPHP) and tri-n-butyl phosphate (TNBP) were predominant at the outer bay (B sites) sediment samples. Source identification via principal component analysis, land use regression statistics, and δ13C analysis indicate that PCBs were mainly sourced from the atmospheric deposition of sugarcane and waste incineration, whereas sewage inputs, aquaculture, and shipping activity were identified as sources of OPE pollution in the Beibu Gulf. A half-year sediment anaerobic culturing experiment was performed for PCBs and OPEs, and the results only exhibited satisfactory dechlorination for PCBs. However, compared with the low ecological risks of PCBs to marine organisms, OPEs (particularly trichloroethyl phosphate (TCEP) and TPHP) exhibited low to medium threats to algae and crustaceans at most sites. Given their increasing usage, high ecological risks, and low bioremediation potential in enrichment cultures, pollution by emerging OPEs warrants close attention.


Assuntos
Retardadores de Chama , Bifenilos Policlorados , Poluentes Químicos da Água , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Retardadores de Chama/análise , Biodegradação Ambiental , Organofosfatos/análise , Fosfatos/análise , China , Ésteres/análise
6.
J Craniofac Surg ; 34(2): 747-750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36166495

RESUMO

At present, there is no unified and accurate method to design the amount of tissue to be removed in alar reduction surgery. The authors present the experience that the crescent-shaped alar resection is based on the innovative equilateral triangle theory. It can accurately estimates the amount of alar tissue to be removed and conforms to the 3-dimensional esthetic concept of the nose. Followed up for 6 to 12 months, took 6 and 12 months postoperative photos, measured the postoperative nasal base width, and conduct a questionnaire satisfaction survey. The width of the nasal base was reduced by an average of 4.4±2.1 mm. The mean visual analog scale score showed: 4.8±1.6 before operation and 7.6±1.2 after the operation ( P <0.05), which revealed satisfactory patient outcomes. This method provides a new idea for the evaluation of nasal alar resection volume and is worthy of clinical application.


Assuntos
Procedimentos de Cirurgia Plástica , Rinoplastia , Humanos , Rinoplastia/métodos , Estética Dentária , Nariz/cirurgia , Técnicas de Sutura , Resultado do Tratamento
7.
J Craniofac Surg ; 34(2): 691-694, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36730867

RESUMO

Free tissue transfer is a great method for the reconstruction of craniofacial defects, especially in complicated situations such as calvarial defects and dura exposure. Latissimus dorsi muscle flap, anterolateral thigh flap, and radial forearm flap are 3 commonly used flaps that have distinct characteristics. The objective of the present study is to share our experiences with microvascular free flap reconstruction of cranium exposure or defects and to compare distinct microvascular free flap options. The authors reviewed 8 cases that received resection and reconstruction of craniofacial tumors. Perioperative and reconstructive techniques employed to improve flap survival, esthetic outcome, and prevent complications in these patients were retrospectively detailed. In addition, the advantages and disadvantages of latissimus dorsi muscle flap, anterolateral thigh flap, and radial forearm flap were illustrated in this study. The authors believe that taking advantage of these flaps according to the characteristics of defects and flaps will contribute to a good functional and esthetic outcome.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Humanos , Estudos Retrospectivos , Estética Dentária , Retalhos de Tecido Biológico/cirurgia , Crânio/cirurgia , Coxa da Perna/cirurgia
8.
Cleft Palate Craniofac J ; : 10556656231170136, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37073080

RESUMO

OBJECTIVE: The objectives of this study were to assess the oral health status and parental perception of oral health needs of pediatric patients in an urban Craniofacial Center. DESIGN: This research utilized a prospective cross-sectional matched study design. The data was collected prospectively via clinical oral examinations measuring dental caries experience and gingival health status. Parental perception of oral health was assessed through a validated questionnaire. SETTING: The study was conducted at a Pediatric Dentistry Department and Craniofacial Center (CFC) in a large urban American city. PATIENTS/PARTICIPANTS: Participants were recruited and enrolled from a CFC and Pediatric Dental Clinic. MAIN OUTCOME MEASURE(S): The outcome measures were the oral health status and parental perception thereof. RESULTS: CFC patients' caries experience in primary teeth was significantly lower than that of a healthy matched cohort, but statistically similar in permanent teeth. CFC patients had significantly higher unmet dental treatment needs. CFC patients had poor oral hygiene and were shown to have significantly higher plaque levels and worse gingival health than that of a healthy matched cohort. Parental perception of oral health did not show a statistically significantly difference between the two groups. CONCLUSIONS: Patients in our study in an urban CFC were found to have a high unmet dental and poor oral hygiene. Despite the poor oral health status, parents of children with craniofacial anomalies did perceive their oral health as different from a matched cohort of patients without these conditions.

9.
Molecules ; 28(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37894580

RESUMO

In the domain of environmental science, pollutants of nanoscale plastic dimensions are acknowledged as subjects of intricate significance. Such entities, though minuscule, present formidable challenges to ecological systems and human health. The diminutive dimensions of these contaminants render their detection arduous, thus demanding the inception of avant-garde methodologies. The present manuscript postulates the employment of the tetraphenylethylene functional group with a fused xanthene (TPEF), a distinguished fluorophore, as an exemplary system for the discernment of nanoplastic particulates. The synthesis and characterization of TPEF have been exhaustively elucidated, revealing its paramount fluorescence attributes and inherent affinity for interaction with nanoplastics. When subjected to comparison with TPEF, nanoplastics are observed to manifest a more pronounced fluorescent luminescence than when associated with the conventional Nile Red (NR). Particularly, the TPEF has shown exceptional affinity for polystyrene (PS) nanoplastics. Further, the resilience of nanoplastics within the hypocotyl epidermis of soybeans, as well as their persistence in mung bean sprouts subsequent to rigorous rinsing protocols, has been meticulously examined. Additionally, this investigation furnishes empirical data signifying the existence of nano-dimensional plastic contaminants within HeLa cellular structures. The urgency of addressing the environmental ramifications engendered by these diminutive yet potent plastic constituents is emphatically highlighted in this manuscript. TPEF paves the way for prospective explorations, with the aspiration of devising efficacious mitigation strategies. Such strategies might encompass delineating the trajectories undertaken by nanoplastics within trophic networks or their ingress into human cellular architectures.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Humanos , Poliestirenos/química , Microplásticos , Células HeLa , Estudos Prospectivos , Ecossistema , Plásticos , Poluentes Químicos da Água/química , Nanopartículas/química
10.
J Am Chem Soc ; 144(49): 22651-22661, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36411055

RESUMO

Biological systems employ non-equilibrium self-assembly to create ordered nanoarchitectures with sophisticated functions. However, it is challenging to construct artificial non-equilibrium nanoassemblies due to lack of control over assembly dynamics and kinetics. Herein, we design a series of linear polymers with different side groups for further coordination-driven self-assembly based on shape-complementarity. Such a design introduces a main-chain confinement which effectively slows down the assembly process of side groups, thus allowing us to monitor the real-time evolution of lychee-like nanostructures. The function related to the non-equilibrium nature is further explored by performing photothermal conversion study. The ability to observe and capture non-equilibrium states in this supramolecular system will enhance our understanding of the thermodynamic and kinetic features as well as functions of living systems.


Assuntos
Nanoestruturas , Polímeros , Polímeros/química , Nanoestruturas/química , Termodinâmica , Cinética
11.
J Am Chem Soc ; 144(36): 16559-16571, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35998652

RESUMO

Molecular geometry represents one of the most important structural features and governs physical properties and functions of materials. Nature creates a wide array of substances with distinct geometries but similar chemical composition with superior efficiency and precision. However, it remains a formidable challenge to construct abiological macromolecules with various geometries based on identical repeating units, owing to the lack of corresponding synthetic approaches for precisely manipulating the connectivity between monomers and feasible techniques for characterizing macromolecules at the single-molecule level. Herein, we design and synthesize a series of tetratopic monomers with chevron stripe shape which serve as the key precursors to produce four distinct types of metallo-macromolecules with well-defined geometries, viz., the concentric hexagon, helicoid polymer, ladder polymer, and cross-linked polymer, via platinum-acetylide couplings. Concentric hexagon, helicoid, and ladder metallo-polymers are directly visualized by transmission electron microscopy, atomic force microscopy, and ultra-high-vacuum low-temperature scanning tunneling microscopy at the single-molecule level. Finally, single-walled carbon nanotubes (SWCNTs) are selected as the guest to investigate the structure-property relationship based on such macromolecules, among which the helicoid metallo-polymer shows high efficiency in wrapping SWCNTs with geometry-dependent selectivity.


Assuntos
Nanotubos de Carbono , Polímeros , Substâncias Macromoleculares/química , Microscopia de Força Atômica , Nanotecnologia/métodos , Nanotubos de Carbono/química , Polímeros/química
12.
Acta Clin Croat ; 61(1): 138-144, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36398079

RESUMO

Three-dimensional printed polyetheretherketone (PEEK) extravascular stent was applied to treat a 14-year-old boy with nutcracker syndrome. Digital subtraction angiography revealed a segment of the left renal vein (LRV) with reduced contrast filling immediately before its inflow into the inferior vena cava, and high-pressure gradient. The three-dimensional reconstruction model demonstrated that the LRV and the duodenum were contracted at the aortomesenteric angle, resulting in LRV compression from the abnormal high-level duodenal compartment. When duodenum courses between the abdominal aorta and superior mesenteric artery (duodenal interposition), the LRV entrapment occurs even at <90 aortomesenteric degrees. Three-dimensional printed PEEK extravascular stent was chosen to elevate the superior mesenteric artery and lower the duodenum position, thus relieving LRV compression. This extravascular application has significant advantages over open surgery, endovascular stenting and artificial vessel procedures with expanded polytetrafluoroethylene. It provides better cellular vitality by ensuring soft tissue proliferation. By reducing external acceleration and centrifugal force, a three-dimensional printed PEEK extravascular stent reduces adverse side effects. Such a stent has a distinctive personalized design, good stiffness, and durability that allows blood vessel growth, preventing stent migration and thrombosis. Therefore, it is suitable for both adult and pediatric patients. According to the abdominal ultrasound and multi-slice computed tomography scan, the postoperative follow-up results were satisfactory one year after surgery. The patient felt well, the blood flow in the LRV was not obstructed, and the blood flow velocity was average. The external stent was in place.


Assuntos
Síndrome do Quebra-Nozes , Adulto , Masculino , Humanos , Adolescente , Criança , Síndrome do Quebra-Nozes/complicações , Síndrome do Quebra-Nozes/cirurgia , Stents/efeitos adversos , Veias Renais/cirurgia , Cetonas , Polietilenoglicóis , Impressão Tridimensional
13.
Bioprocess Biosyst Eng ; 44(11): 2231-2244, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34165619

RESUMO

Bacterial cellulose (BC)-derived materials are given significant attention due to their porous fibrous texture, high crystallinity and extraordinary physico-mechanical properties. The main reason for the restricted use of BC is its high production cost. To reduce the production cost, the suitability of pear residue for the production of BC and pear vinegar was investigated. Komagataeibacter rhaeticus and Komagataeibacter intermedius with high fermentation ability screened from the surface of vinegar film of millet fermentation were used to produce BC and pear vinegar simultaneously. Through response surface optimization, the maximum yield of BC from pear residue medium was 10.94 ± 0.42 g/L, which was higher than the synthesis medium generally used for Acetobacter strains. When pear residue medium was incubated at 30 °C for 7 days, the contents of total acid and soluble solids were greater than 0.3 g/100 mL and 3%, respectively, which met the standard requirements for fruit vinegar. The flavour components of pear vinegar were determined using gas chromatography-mass spectrometry. The pear vinegar showed similar flavour characteristics to conventional fruit vinegar. This research not only solved the utilization of agricultural resources but also avoided the discharge of waste liquid when producing BC. In addition, a more environmentally friendly and less expensive way to produce BC and pear vinegar was achieved.


Assuntos
Ácido Acético/metabolismo , Acetobacteraceae/metabolismo , Celulose/metabolismo , Fermentação , Pyrus/metabolismo , Acetobacteraceae/classificação , Adulto , Meios de Cultura , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Microscopia Eletrônica de Varredura , Microextração em Fase Sólida , Especificidade da Espécie , Espectroscopia de Infravermelho com Transformada de Fourier , Paladar , Adulto Jovem
14.
Sensors (Basel) ; 21(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34770253

RESUMO

Soil moisture measurement is very important for soil system monitoring. Compared to the traditional thermo-gravimetric technique, which is time-consuming and can be only performed in labs, the optic-fiber technique has unique advantages, such as small size, remote application in fields, fast response time and immunity to electromagnetic fields. In this paper, the soil moisture is measured by using a polymer optical fiber Bragg grating (POFBG) probe with a packaged dimension of 40 mm × 15 mm × 8 mm. Due to the intrinsic water-absorbing property of poly (methyl methacrylate) (PMMA), optical fiber Bragg gratings based on PMMA have been widely investigated for humidity measurement. Taking advantage of this, a sensor based on the POFBG is investigated to verify the soil condition. The POFBG is protectively integrated inside a stainless-steel package. A window is opened with a thin polypropylene mat as a filter, which allows the air to go through but prevents the soil from going inside to pollute the POFBG. The sensor probe is embedded in soils with different gravimetric soil moisture contents (SMCs) ranging from 0% to 40% and, then, insulated by polyethylene films to minimize the impact from the external environment, showing an average temperature cross sensitivity of -0.080 nm/°C. For a constant temperature, an exponential relationship between the Bragg wavelength and the SMC is obtained. For the SMCs between 8% and 24%, linear relationships are presented showing a temperature-corresponded sensitivity between 0.011 nm/% and 0.018 nm/%. The maximal sensitivity is calculated to be 0.018 nm/% at 20 °C, which is 28 times as high as that in the previous work. For the SMC over 24%, the sensor becomes insensitive because of humidity saturation in the cavity of the sensor probe. Though temperature cross sensitivity is problematic for SMC measurement, the influence could be eliminated by integrating another humidity-insensitive temperature sensor, such as a silica FBG temperature sensor.


Assuntos
Polimetil Metacrilato , Água , Umidade , Solo , Temperatura
15.
J Am Chem Soc ; 142(13): 6196-6205, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32150680

RESUMO

During the past few decades, the study of the single polymer chain has attracted considerable attention with the goal of exploring the structure-property relationship of polymers. It still, however, remains challenging due to the variability and low atomic resolution of the amorphous single polymer chain. Here, we demonstrated a new strategy to visualize the single metallopolymer chain with a hexameric or trimeric supramolecule as a repeat unit, in which Ru(II) with strong coordination and Fe(II) with weak coordination were combined together in a stepwise manner. With the help of ultrahigh-vacuum, low-temperature scanning tunneling microscopy (UHV-LT-STM) and scanning tunneling spectroscopy (STS), we were able to directly visualize both Ru(II) and Fe(II), which act as staining reagents on the repeat units, thus providing detailed structural information for the single polymer chain. As such, the direct visualization of the single random polymer chain is realized to enhance the characterization of polymers at the single-molecule level.


Assuntos
Complexos de Coordenação/química , Ferro/química , Polímeros/química , Rutênio/química , Técnicas de Química Sintética , Complexos de Coordenação/síntese química , Microscopia de Tunelamento , Polímeros/síntese química
16.
J Am Chem Soc ; 140(24): 7674-7680, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29856215

RESUMO

Herein, we report the preparation of a multifunctional metallacage-core supramolecular gel by orthogonal metal coordination and host-guest interactions. A tetragonal prismatic cage with four appended 21-crown-7 (21C7) moieties in its pillar parts was first prepared via the metal-coordination-driven self-assembly of cis-Pt(PEt3)2(OTf)2, tetraphenylethene (TPE)-based sodium benzoate ligands and linear dipyridyl ligands. Further addition of a bisammonium linker to the cage delivered a supramolecular polymer network via the host-guest interactions between the 21C7 moieties and ammonium salts, which formed a supramolecular gel at relatively higher concentrations. Due to the incorporation of a TPE derivative as the fluorophore, the gel shows emission properties. Multiple stimuli responsiveness and good self-healing properties were also observed because of the dynamic metal coordination and host-guest interactions used to stabilize the whole network structure. Moreover, the storage and loss moduli of the gel are 10-fold those of the gel without the metallacage cores, indicating that the rigid metallacage plays a significant role in enhancing the stiffness of the gel. The studies described herein not only enrich the functionalization of fluorescent metallacages via elegant ligand design but also provide a way to prepare stimuli-responsive and self-healing supramolecular gels as robust and smart materials.


Assuntos
Complexos de Coordenação/química , Géis/química , Substâncias Macromoleculares/química , Compostos Organoplatínicos/química , Polímeros/química , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/química , Complexos de Coordenação/síntese química , Éteres de Coroa/síntese química , Éteres de Coroa/química , Fluorescência , Géis/síntese química , Substâncias Macromoleculares/síntese química , Compostos Organoplatínicos/síntese química , Polímeros/síntese química , Reologia
17.
Eur Spine J ; 25(6): 1881-90, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26968876

RESUMO

PURPOSE: We aimed to analyze the clinical and radiographic efficacy of a new zero-profile anchored spacer called the ROI-C in anterior discectomy and fusion (ACDF) for multilevel cervical spondylotic myelopathy (MCSM). METHOD: We retrospectively reviewed the clinical, radiological outcomes and complications of multilevel ACDF with the ROI-C or with the polyetheretherketone (PEEK) cages with an anterior plate. From April 2011 to April 2014, 60 patients with MCSM were operated on using ACDF, with the ROI-C in 28 patients and PEEK cages with an anterior plate in 32 patients. The operative time, intraoperative blood loss, and clinical and radiological results were compared between the ROI-C group and the cage-plate group. RESULTS: The mean follow-up time was 23.8 ± 6.6 months, ranging from 12 to 36 months. At the first month and the last follow-up, the neck disability index (NDI) scores were decreased, and the Japanese Orthopedic Association (JOA) scores were significantly increased, compared with the presurgical measurements in both groups. There were no significant differences in NDI scores or JOA scores between the two groups (P > 0.05), but there were significant differences in the operation time, blood loss and the presence of dysphagia (P < 0.05). In addition, the cervical Cobb angle and disk height showed significant corrections, compared to those measured before the operation. There was no adjacent disc degeneration observed in the ROI-C group, and one patient with skip levels showed disc degeneration of the normal level between the skip levels in the cage-plate group. The degeneration rate of the cage-plate group was 3.1 %. CONCLUSIONS: The primary clinical and radiographic efficacies of both ROI-C and cages with plates in ACDF for MCSM were satisfactory; both approaches could improve and maintain cervical lordosis and disk height. However, the ROI-C was associated with a simpler operation, a shorter operation time, less blood loss, and a lower risk of postoperative dysphagia compared to the PEEK cage with an anterior plate.


Assuntos
Vértebras Cervicais/cirurgia , Discotomia/instrumentação , Fusão Vertebral/instrumentação , Espondilose/cirurgia , Adulto , Idoso , Benzofenonas , Perda Sanguínea Cirúrgica , Placas Ósseas , Transtornos de Deglutição/etiologia , Feminino , Seguimentos , Humanos , Cetonas , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Polietilenoglicóis , Polímeros , Complicações Pós-Operatórias , Próteses e Implantes , Estudos Retrospectivos
18.
Angew Chem Int Ed Engl ; 55(36): 10662-6, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27485314

RESUMO

Polydopamine (PDA), which is biodegradable and is derived from naturally occurring products, can be employed as an electrode material, wherein controllable partial oxidization plays a key role in balancing the proportion of redox-active carbonyl groups and the structural stability and conductivity. Unexpectedly, the optimized PDA derivative endows lithium-ion batteries (LIBs) or sodium-ion batteries (SIBs) with superior electrochemical performances, including high capacities (1818 mAh g(-1) for LIBs and 500 mAh g(-1) for SIBs) and good stable cyclabilities (93 % capacity retention after 580 cycles for LIBs; 100 % capacity retention after 1024 cycles for SIBs), which are much better than those of their counterparts with conventional binders.


Assuntos
Fontes de Energia Elétrica , Indóis/química , Lítio/química , Polímeros/química , Sódio/química , Condutividade Elétrica , Eletrodos , Desenho de Equipamento , Íons/química , Modelos Moleculares , Oxirredução
19.
Arch Toxicol ; 88(2): 241-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24030355

RESUMO

Sodium fluoride (NaF) is associated with embryonic and fetal development abnormalities, but the mechanism by which this occurs is unclear. DNA methylation, an important epigenetic reprogramming mechanism, is essential for normal embryonic development. Thus, we investigated the effect of NaF on DNA methylation in early mouse embryos, as well as mouse sperm and liver using bisulfite sequencing and ELISA. Data indicate that H19, a paternally imprinted gene, compared to control embryos, was less methylated in 8-cell embryos from pregnant mice treated with NaF (100 mg/l) in drinking water for 48 h. Peg3, a maternally imprinted gene, and the Line1 repeated sequence were similarly methylated in NaF-treated and control embryos. Oral ingestion of NaF for 35 days did not significantly change Line1 and genomic global DNA methylation in the liver. H19, Rasgrf1, Line1, and genomic global DNA methylation were also similar in NaF-treated and control sperm. Female mice mated with NaF-treated male mice (35 days) had less methylated H19, but Peg3 was significantly more methylated. Line1 was similarly methylated in treated 8-cell embryos, compared to control embryos. NaF treatment of male mice before copulation significantly increased the expression of H19 in blastocysts, whereas H19 expression was not detected in 8-cell embryos. Data suggest that NaF may interact directly with the embryo to disrupt the maintenance of normal gene imprinting during pregnancy. Long-term NaF exposure of males may not directly affect DNA methylation of the sperm and liver, but the sperm may signal to early embryos with abnormal gene imprinting.


Assuntos
Metilação de DNA/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/genética , RNA Longo não Codificante/genética , Fluoreto de Sódio/toxicidade , Animais , Blastocisto/efeitos dos fármacos , Feminino , Impressão Genômica , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Espermatozoides/efeitos dos fármacos
20.
PLoS One ; 19(6): e0304052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913628

RESUMO

A diaphragm pump is a type of volumetric pump that has excellent sealing performance. An electromagnetic diaphragm pump is a kind of widely adopted diaphragm pump that has a simple structure, low power loss, and high cost performance. However, the calculation method of deformation for the electromagnetic diaphragm pump rubber diaphragm is presently lacking. Herein, a calculating method of deformation for the electromagnetic diaphragm pump rubber diaphragm is proposed. By establishing and analyzing a deformation model of the electromagnetic diaphragm pump rubber diaphragm, a theoretical relationship between the deformation of the electromagnetic diaphragm pump rubber diaphragm, the size of the electromagnetic diaphragm pump rubber diaphragm and the pressure of fluid is determined. The experimental results indicate that the biggest difference between the tested axial deformation and the calculated axial deformation of the electromagnetic diaphragm pump rubber diaphragm is 0.04 mm and the calculation results show agreement with the experimental results.


Assuntos
Fenômenos Eletromagnéticos , Borracha , Borracha/química , Desenho de Equipamento , Modelos Teóricos
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