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1.
Ann Plast Surg ; 93(2S Suppl 1): S47-S50, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39101848

RESUMO

BACKGROUND: Postoperative infection of breast implants can lead to implant removal and other complications. This study aimed to investigate the presence of costal cartilage infection following breast implant surgery and the diagnostic role of PET/CT in identifying this rare complication. PATIENTS AND METHODS: A retrospective study included 16 patients with persistent infections after breast implant removal surgery. Patients underwent PET/CT scans before surgery, and surgical plans were made based on PET/CT findings. Surgical procedures were guided by PET/CT, and specimens were collected for pathological examination and microbiological culture. Follow-up assessments were performed at 1, 3, and 12 months postoperatively. RESULTS: Among the 16 patients, 11 were diagnosed with costal cartilage infection, whereas 5 had subcutaneous soft tissue infections. PET/CT accurately identified costal cartilage infection in all cases and localized the infected costal cartilage in the majority of cases. Microbiological culture results showed various pathogens. All patients were cured with one or staged surgery. CONCLUSION: Costal cartilage infection following breast implant surgery is a significant concern. PET/CT plays a crucial role in the accurate diagnosis and localization of infected costal cartilage, aiding in appropriate surgical management. Patients should be closely monitored for the possibility of costal cartilage infection when experiencing persistent symptoms after breast implant surgery.


Assuntos
Implante Mamário , Implantes de Mama , Cartilagem Costal , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Implantes de Mama/efeitos adversos , Cartilagem Costal/transplante , Implante Mamário/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/etiologia , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/microbiologia , Remoção de Dispositivo , Idoso
2.
Huan Jing Ke Xue ; 44(12): 6564-6575, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098384

RESUMO

Based on the online monitoring data of volatile organic compounds(VOCs) and ozone(O3) in Liaocheng in June 2021, the concentration levels, compositional characteristics, daily variation characteristics, and ozone formation potential(OFP) of VOCs on polluted days and clean days were systematically analyzed. Potential source areas of VOCs were identified by the potential source contribution function(PSCF) and concentration-weighted trajectory(CWT). The sources of VOCs in Liaocheng were analyzed using the characteristic species ratio and positive matrix factorization(PMF). The results showed that the hourly mean values of VOCs concentrations on polluted days and clean days in Liaocheng in June 2021 were(115.38±59.12) µg·m-3 and(88.10±33.04) µg·m-3, respectively, and the concentration levels of VOCs in each category showed that oxygenated volatile organic compounds(OVOCs)>alkanes>halogenated hydrocarbons>aromatic hydrocarbons>alkenes>alkynes>organosulfur. VOCs species with large differences in concentrations between polluted and clean days were among the top ten species of the hourly mean VOCs concentrations. The daily trends of concentrations of total VOCs, alkanes, alkynes, aromatic hydrocarbons, halogenated hydrocarbons, and organosulfur showed that the daytime concentrations were lower than the nighttime concentrations, and the daily changes in OVOCs concentrations showed the characteristics of high in the daytime and low at nighttime. The OFP was 285.29 µg·m-3 on polluted days and 212.00 µg·m-3 on clean days, and OVOCs, alkenes, and aromatic hydrocarbons contributed significantly to ozone formation. The PSCF and CWT results found that the potential source areas of VOCs in Liaocheng were concentrated in the northern and northeastern part of Dongchangfu District and the central and southwestern part of Chiping District. The results of the characteristic species ratio indicated that the VOCs in Liaocheng might have been more from coal combustion, gasoline volatilization, and motor vehicle exhaust. The results of PMF showed that industrial emission sources(30.57%), motor vehicle exhaust and oil and gas volatilization sources(19.44%), combustion sources(17.23%), air aging and secondary generation sources(13.69%), solvent usage sources(12.75%), and natural sources(6.32%) were the main sources of VOCs in Liaocheng.

3.
Angew Chem Int Ed Engl ; 62(21): e202300604, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36949023

RESUMO

Hydrogen peroxide (H2 O2 ) is an indispensable basic reagent in various industries, such as textile bleach, chemical synthesis, and environmental protection. However, it is challenging to prepare H2 O2 in a green, safe, simple and efficient way under ambient conditions. Here, we found that H2 O2 could be synthesized using a catalytic pathway only by contact charging a two-phase interface at room temperature and normal pressure. Particularly, under the action of mechanical force, electron transfer occurs during physical contact between polytetrafluoroethylene particles and deionized water/O2 interfaces, inducing the generation of reactive free radicals (⋅OH and ⋅O2 - ), and the free radicals could react to form H2 O2 , yielding as high as 313 µmol L-1 h-1 . In addition, the new reaction device could show long-term stable H2 O2 production. This work provides a novel method for the efficient preparation of H2 O2 , which may also stimulate further explorations on contact-electrification-induced chemistry process.

4.
Nanoscale ; 14(20): 7579-7588, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35506868

RESUMO

Synthesis of high-quality ZnO/ZnS heterostructures with tunable phase and controlled structures is in high demand due to their adjustable band gap and efficient electron-hole pair separation. In this report, for the first time, remote heteroepitaxy of single-crystalline ZnO/ZnS core/shell nanowire arrays has been realized using amorphous HfO2 as the buffer layer. Zinc blende or wurtzite ZnS epilayer can be efficiently fabricated under the same thermal deposition condition by adjusting the buffer layer thickness, even among the same batch of products, respectively. Structural characterization reveals "(01-10)ZnOwz//(2-20)ZnSZB, [0001]ZnOWZ//[001]ZnSZB" and "(01-10)ZnOWZ//(01-10)ZnSWZ, [0002]ZnOWZ//[0002]ZnSWZ" epitaxial relationships between the core and the shell, respectively. The cathodoluminescence measurement demonstrates that the tuning of the optical properties can be accomplished by preparing a heterostructure with HfO2, in which a strong green emission increases at the expense of the quenching of UV emission. In addition, the core/shell heterostructure based Schottky diode exhibits an asymmetrical rectifying behavior and an outstanding photo-electronic switching-effect. We believe that the aforementioned results could provide fundamental insights for epitaxial growth of structure-tunable ZnO/ZnS heterostructures on the nanoscale. Furthermore, this promising route buffered by the high-k material can broaden the options for fabricating heterojunctions and promote their application in photoelectric nanodevices.

5.
ChemSusChem ; 15(14): e202200340, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35377527

RESUMO

Hole transport materials (HTMs) play a requisite role in n-i-p perovskite solar cells (PSCs). The properties of HTMs, such as hole extraction efficiency, chemical compatibility, film morphology, ion migration barrier, and so on, significantly affect PSCs' power conversion efficiencies (PCEs) and stabilities. Up till now, researchers have devoted much attention to developing new types of HTMs as well as promoting pristine HTMs using numerous strategies. In this Review, we summarize the design strategies of various common HTMs for n-i-p PSCs are comprehensively discussed from two separate aspects (additive and non-additive engineering). Additive engineering generally tunes electronic properties of HTMs while non-additive engineering basically modifies their steric structures. Critical analysis and comparison between these design strategies are provided, considering the overall PCEs and stabilities of PSCs. Finally, a brief perspective on future promising design strategies for HTMs is given, in order to fabricate efficient and stable n-i-p devices for the commercialization of PSCs.

6.
Nanoscale ; 13(26): 11525-11533, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34180928

RESUMO

II-VI semiconductor heterojunctions show huge potential for application in nanodevice fabrication due to their type-II alignments owing to the better spatial separation of electrons and holes. However, the hetero-epitaxial growth of high-quality heterostructures is still a challenge, especially for materials with large lattice mismatch. In this work, well-aligned single-crystalline ZnO/ZnS core/shell nanorod arrays were obtained by introducing an Al2O3 buffer layer. It is interesting that the nature of the ZnS layer varies with the thickness of the Al2O3 layer. When Al2O3 is less than 2 nm, the interaction between the substrate and epilayer is strong enough to penetrate through the buffer layer, enabling the growth of ZnS on Al2O3-coated ZnO nanorod arrays. On the basis of detailed characterization, a rational growth mechanism of the core/shell heterostructure is proposed, in which the Al2O3 interlayer can eliminate voids due to the Kirkendall effect around the interface and accommodate a misfit dislocation between the inner ZnO and outer ZnS, resulting in more sufficient strain relaxation in the epitaxy. In addition, cathodoluminescence measurements demonstrate that the optical properties of the ZnO/ZnS heterostructure could be effectively improved by taking advantage of the thin Al2O3. The I-V curves characterized by PeakForce tunneling atomic force microscopy reveal that the heterostructure shows a typical rectifying behavior and good photoresponse to ultraviolet light. These findings may provide a reasonable and effective strategy for the growth of highly lattice-mismatched heterostructure arrays buffered by the Al2O3 layer, broadening the options for fabricating heterojunctions and promoting their applications in optoelectronic devices.

7.
Anal Chim Acta ; 1105: 139-146, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32138912

RESUMO

An effective ratiometric fluorescent probe based on silicon particles/gold nanoclusters (SiNPs/AuNCs) nanohybrid has been fabricated and applied to be a "on-off-on" switch sensing platform for detection of Hg2+ and cysteine. In this elaborated sensing platform, the SiNPs just acted as internal reference signal, providing a build-in correction for background interferences and environmental effects, to which the AuNCs as a signal report unit for Hg2+ response was covalently grafted by amidation reaction. The fluorescence intensity of SiNPs/AuNCs could be effectively quenched upon adding Hg2+, accompanied with an easily distinguishable fluorescent color change. The ratiometric fluorescence signal (F649/F511) of the established nanoprobe was linearly proportional to the concentration of Hg2+ ranging from 0.02 to 24 µM with a low detection limit of 5.6 nM, which is below the guideline value of Hg2+ in drinking water set by the World Health Organization. Interestingly, upon addition of cysteine, the Hg2+-quenched fluorescence intensity was recovered gradually. Furthermore, the approach developed has also been utilized for Hg2+ detection in real complex biological samples with satisfactory results. More importantly, benefiting from the good water-solubility and excellent biocompatibility, this nanoprobe can monitor the intracellular Hg2+ and cysteine in living cells, indicating its potential applications in advanced biosensing and bioimaging.


Assuntos
Cisteína/análise , Corantes Fluorescentes/química , Mercúrio/análise , Nanopartículas/química , Imagem Óptica , Animais , Água Potável/química , Ouro/química , Células HeLa , Humanos , Camundongos , Células NIH 3T3 , Tamanho da Partícula , Silício/química , Espectrometria de Fluorescência , Propriedades de Superfície
8.
Pain ; 161(7): 1584-1596, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32149862

RESUMO

EphrinB-EphB receptor tyrosine kinases have been demonstrated to play important roles in pain processing after peripheral nerve injury. We have previously reported that ephrinB-EphB receptor signaling can regulate excitability and plasticity of neurons in spinal dorsal horn, and thus contribute to spinal central sensitization in neuropathic pain. How EphB receptor activation influences excitability of primary neurons in dorsal root ganglion (DRG), however, remains unknown. Here, we report that EphB receptor activation facilitates calcium influx through N-methyl-D-aspartate receptor (NMDAR) dependent and independent manners. In cultured DRG cells from adult rats, EphB1 and EphB2 receptors were expressed in neurons, but not the glial cells. Bath application of EphB receptor agonist ephrinB2-Fc induced NMDAR-independent Ca influx, which was from the extracellular space rather than endoplasmic reticulum. EphB receptor activation also greatly enhanced NMDAR-dependent Ca influx and NR2B phosphorylation, which was prevented by pretreatment of Src kinase inhibitor PP2. In nerve-injured DRG neurons, elevated expression and activation of EphB1 and EphB2 receptors contributed to the increased intracellular Ca concentration and NMDA-induced Ca influx. Repetitive intrathecal administration of EphB2-Fc inhibited the increased phosphorylation of NR2B and Ca-dependent subsequent signals Src, ERK, and CaMKII as well as behaviorally expressed pain after nerve injury. These findings demonstrate that activation of EphB receptors can modulate DRG neuron excitability by facilitating Ca influx directly or through Src kinase activation-mediated NMDA receptor phosphorylation and that EphB receptor activation is critical to DRG neuron hyperexcitability, which has been considered critical to the subsequent spinal central sensitization and neuropathic pain.


Assuntos
Receptores da Família Eph , Quinases da Família src , Animais , Cálcio , Hiperalgesia , Fosforilação , Ratos , Ratos Sprague-Dawley , Receptores da Família Eph/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Células Receptoras Sensoriais/metabolismo , Quinases da Família src/metabolismo
9.
J Pain ; 21(7-8): 836-847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31785403

RESUMO

Neuropathic pain is difficult to treat and remains a major clinical challenge worldwide. While the mechanisms which underlie the development of neuropathic pain are incompletely understood, interferon signaling by the immune system is known to play a role. Here, we demonstrate a role for interferon ß (IFNß) in attenuating mechanical allodynia induced by the spared nerve injury in mice. The results show that intrathecal administration of IFNß (dosages up to 5,000 U) produces significant, transient, and dose-dependent attenuation of mechanical allodynia without observable effects on motor activity or feeding behavior, as is common with IFN administration. This analgesic effect is mediated by the ubiquitin-like protein interferon-stimulated gene 15 (ISG15), which is potently induced within the spinal cord following intrathecal delivery of IFNß. Both free and conjugated ISG15 are elevated following IFNß treatment, and this effect is increased in UBP43-/- mice lacking a key deconjugating enzyme. The IFNß-mediated analgesia reduces MAPK signaling activation following nerve injury, and this effect requires induction of ISG15. These findings highlight a new role for IFNß, ISG15, and MAPK signaling in immunomodulation of neuropathic pain and may lead to new therapeutic possibilities. PERSPECTIVE: Neuropathic pain is frequently intractable in a clinical setting, and new treatment options are needed. Characterizing the antinociceptive potential of IFNß and the associated downstream signaling pathways in preclinical models may lead to the development of new therapeutic options for debilitating neuropathies.


Assuntos
Analgésicos/farmacologia , Citocinas , Hiperalgesia/tratamento farmacológico , Interferon beta/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Medula Espinal/metabolismo , Analgésicos/administração & dosagem , Animais , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Interferon beta/administração & dosagem , Masculino , Camundongos , Camundongos Knockout , Nervo Isquiático/lesões , Medula Espinal/efeitos dos fármacos , Ubiquitina Tiolesterase/genética , Ubiquitinas/efeitos dos fármacos , Ubiquitinas/metabolismo
10.
Front Microbiol ; 10: 3094, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038542

RESUMO

Talaromyces marneffei is a common cause of infection in immunocompromised patients in Southeast Asia and Southern China. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the cytotoxic processes of the host immune system and grow inside host macrophages. These mechanisms that allow T. marneffei to survive macrophage-induced death are poorly understood. In this study, we examined the role of a calcineurin homolog (cnaA) from T. marneffei during growth, morphogenesis and infection. Deletion of the cnaA gene in T. marneffei resulted in a strain with significant defects in conidiation, germination, morphogenesis, cell wall integrity, and resistance to various stressors. The ΔcnaA mutant showed a lower minimal inhibitory concentration (MIC) against caspofungin (16 µg/ml to 2 µg/ml) and micafungin (from 32 µg/ml to 4 µg/ml) compared with the wild-type. These results suggest that targeting calcineurin in combination with echinocandin treatment may be effective for life-threatening systemic T. marneffei infection. Importantly, the cnaA mutant was incapable of adapting to the macrophage environment in vitro and displayed virulence defects in a mouse model of invasive talaromycosis. For the first time, a role has been shown for cnaA in the morphology and pathogenicity of a dimorphic pathogenic filamentous fungus.

11.
Biosens Bioelectron ; 106: 64-70, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29414090

RESUMO

An ultrasensitive and stable "dual-potential" ratiometric electrochemiluminescence (ECL) sensor is reported for specific DNA, the femtomolar detection limit (0.12 fM, S/N = 3) and high selectivity insure its potential applications in cancer biomarkers searching or monitoring. The excellent performance of the sensor comes from simultaneously fabricated layer by layer structure "target DNA + Hemin / Au-Luminol NPs / DNA* / sl DNA / TGA / QDs / MWNTs / GCE" mode which was based on the enhancing effect of luminol by G-quadruplex / hemin and Au nanoparticles and the quenching effect of CdSe/ZnS by G-quadruplex / hemin. (i) DNA-SH could combine with Au-Luminol NPs via S-Au bond to solve the problem of poor solubility and weak ECL intensity of luminol in neutral medium. (ii) Target DNA and Hemin formed the G-quadruplex / hemin peroxidase mimicking DNAzyme could enhance the ECL of luminol and quench the ECL of CdSe/ZnS simultaneously. (iii) DNA* was employed to increase a certain distance between CdSe/ZnS and Au-Luminol for enhancing the CdSe/ZnS QDs initial ECL intensity. The dual-potential ratiometric mode lower the influence of background and side reaction of the ECL sensor which were the most important factors in trace sensing.


Assuntos
Técnicas Biossensoriais , DNA/isolamento & purificação , Quadruplex G , DNA/química , DNA Catalítico/química , Ouro/química , Hemina/química , Humanos , Limite de Detecção , Medições Luminescentes , Luminol/química , Nanopartículas Metálicas/química , Peroxidase/química , Pontos Quânticos/química
12.
Chemistry ; 24(14): 3499-3505, 2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-29315861

RESUMO

An effective dual-emission fluorescent metal-organic framework (MOF)-based nanoprobe has been established for ultrasensitive and rapid ratiometric detection of Cu2+ . Such a nanoprobe was prepared by encapsulating fluorescein isothiocyanate (FITC), and Eu(III) complex-functionalized Fe3 O4 into the zeolitic imidazolate framework material (ZIF-8). In this nanoprobe, FITC was used as a reference signal, thus improving the influence of external uncertainties. The Eu-complex signal could be quenched after adding an amount of Cu2+ . The ZIF-8 could enrich the target analytes, which can amplify the fluorescence signal due to the good adsorption properties of the ZIF-8. Based on above structural and compositional features, the detection limit of the nanoprobe is 0.1 nm for Cu2+ , almost 2×104 times lower than the maximum allowable amount of Cu2+ in drinking water, which constructed a platform for effective detection of Cu2+ . Using the nanoprobe to detect Cu2+ in aqueous solution is rapid and the probe still remained stable. Additionally, this sensor for the ratiometric fluorescence imaging of copper ions was also certified in real samples and live cells.


Assuntos
Cobre/química , Cobre/análise , Limite de Detecção , Estruturas Metalorgânicas , Estrutura Molecular , Espectrometria de Fluorescência
13.
J Nanosci Nanotechnol ; 15(4): 2939-43, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26353517

RESUMO

The excellent thermal performance of carbon nanotube (CNT) has been noticed long ago and attracted much attention. In the experiments, the electrical and thermal contact resistances remain the unsolved key problems causing undesirable measurement uncertainty. Recently, a micro-Raman spectroscopy technique has been applied to perform non-contact measurement for individual CNT, thus the contact resistances during the measurement process can be avoided. In this method, the temperature rise of CNT is a function of laser absorption probability and thermal properties, these parameters are coupled together. In this work, the thermal conductivity and optical absorption of the same CNT sample are decoupled and determined simultaneously. The thermal conductivity is obtained by measuring the temperature rise caused by a direct current heating, where the laser heating effect can be eliminated. Then the optical absorption is obtained by solving the heat transfer equation considering the thermal conductivity as a known parameter. The CNT sample is 24.8 µm in length and 3 nm in diameter. The measured thermal conductivity is 2630 Wm(-1)K(-1) and the optical absorption is 0.194%. The heat transfer coefficient is evaluated using a kinetic two-layer model, which has been proven by the previous experiment. Because the length of CNT is much larger than the size of the focused laser spot, the experimental result is insensitive to the contact resistances at the ends of CNT.

14.
Chin Med J (Engl) ; 124(19): 3070-3, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22040558

RESUMO

BACKGROUND: Periodontal disease is closely related to type 2 diabetes and is an important complication of diabetes. This study aimed to investigate the effect of periodontal treatment on levels of blood glucose (Glu) and glycosylated hemoglobin (HbA1c) among elderly patients with type 2 diabetes and periodontal disease. METHODS: A total of 107 elderly patients with type 2 diabetes and periodontal disease were selected and divided into two groups according to their HbA1c levels. Group A was a well-controlled diabetic group and group B was uncontrolled. Their probing depth (PD), attachment loss (AL), the value of Glu and HbA1c were analyzed before periodontal treatment and 4 months later. RESULTS: There was a significant difference in periodontal condition between groups A and B (P < 0.01). The periodontal condition for both groups was significantly (P < 0.01) improved after periodontal therapy. The effect of treatment in group A was more pronounced than group B, and the difference was significant (P < 0.01). After the periodontal treatment, Glu and HbA1c were reduced significantly in both groups (P < 0.05). CONCLUSIONS: Periodontal condition is related to the control of Glu level among elderly patients with type 2 diabetes and periodontal disease. Periodontal treatment can effectively reduce the level of Glu and HbA1c as well as improve the periodontal condition in elderly type-2 diabetes patients with periodontal disease.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas/análise , Doenças Periodontais/sangue , Doenças Periodontais/complicações , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/terapia
15.
Artigo em Inglês | MEDLINE | ID: mdl-12237722

RESUMO

Biliverdin reducatase was purified from pig-kidney to homogeneous form through DEAE 52-cellulose, Sephadex G-100 and Procion red HE 3B-Sepharose 4B column chromatography, The enzyme was estimated to be a monomer with a molecular weight of 66kD by SDS-PAGE. A gel staining in basic-pyridine solution of heme was used to identify purified biliverdin reductase. The enzyme utilized NADPH and NADH as electron donors for the reduction of biliverdin to produce bilirubin. The apparent K(m) values for biliverdin were established to be 1.25 &mgr;M with NADPH and 2.52 &mgr;M with NADH.

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