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1.
Nanotechnology ; 32(50)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34555813

RESUMO

In this paper, silver micro/nanostructures composed of sintered nanoparticles were printed by capturing silver nanoparticles in water with 800 nm femtosecond laser trapping. Relationships of laser power, scanning speed, nanoparticle concentration, and the width and morphology of fabricated silver wire were systematically investigated. It is found that low scanning speed and high nanoparticle concentration favor the printing of silver wire with good morphology. A silver wire with width of 305 nm was printed. Electrical resistivities of printed wires are about 24 times that of bulk silver. Silver grid structures and dot arrays were printed by using this technology. Several three-dimensional silver cuboid structures were also printed. This work provides a protocol for printing of three-dimensional metallic micro/nanostructures using laser trapping. These printed structures have great application prospects in metamaterials, flexible electronics, and SERS.

2.
Int J Nanomedicine ; 15: 6503-6518, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922013

RESUMO

OBJECTIVE: A non-lipolysis nanoemulsion (NNE) was designed to reduce the first-pass metabolism of raloxifene (RAL) by intestinal UDP-glucuronosyltransferases (UGTs) for increasing the oral absorption of RAL, coupled with in vitro and in vivo studies. METHODS: In vitro stability of NNE was evaluated by lipolysis and the UGT metabolism system. The oral bioavailability of NNE was studied in rats and pigs. Finally, the absorption mechanisms of NNE were investigated by in situ single-pass intestinal perfusion (SPIP) in rats, Madin-Darby canine kidney (MDCK) cells model, and lymphatic blocking model. RESULTS: The pre-NNE consisted of isopropyl palmitate, linoleic acid, Cremophor RH40, and ethanol in a weight ratio of 3.33:1.67:3:2. Compared to lipolysis nanoemulsion of RAL (RAL-LNE), the RAL-NNE was more stable in in vitro gastrointestinal buffers, lipolysis, and UGT metabolism system (p < 0.05). The oral bioavailability was significantly improved by the NNE (203.30%) and the LNE (205.89%) relative to the suspension group in rats. However, 541.28% relative bioavailability was achieved in pigs after oral NNE intake compared to the suspension and had two-fold greater bioavailability than the LNE (p < 0.05). The RAL-NNE was mainly absorbed in the jejunum and had high permeability at the intestine of rats. The results of both SPIP and MDCK cell models demonstrated that the RAL-NNE was absorbed via endocytosis mediated by caveolin and clathrin. The other absorption route, the lymphatic transport (cycloheximide as blocking agent), was significantly improved by the NNE compared with the LNE (p < 0.05). CONCLUSION: A NNE was successfully developed to reduce the first-pass metabolism of RAL in the intestine and enhance its lymphatic transport, thereby improving the oral bioavailability. Altogether, NNE is a promising carrier for the oral delivery of drugs with significant first-pass metabolism.


Assuntos
Absorção Fisico-Química , Emulsões/química , Lipólise , Nanopartículas/química , Cloridrato de Raloxifeno/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Transporte Biológico , Sobrevivência Celular , Cães , Emulsões/administração & dosagem , Feminino , Intestinos/fisiologia , Linfa/metabolismo , Células Madin Darby de Rim Canino , Masculino , Polietilenoglicóis , Ratos Sprague-Dawley , Tensoativos/química , Suínos
3.
CNS Neurosci Ther ; 26(8): 829-836, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32374521

RESUMO

AIMS: To investigate the relationship between peripheral leukocyte dynamics and the outcome of large hemispheric infarction (LHI) patients. METHODS: Patients with acute LHI admitted to the neuro-intensive care unit of Xuanwu Hospital from 2013 to 2017 were prospectively enrolled and followed up for 6 months after LHI. RESULTS: A total of 84 LHI patients were included, 38 patients suffered brain herniation and 20 patients died from stroke. Compared to patients with benign course, LHI patients with fatal outcome showed larger infarcts and more severe brain edema (P < .01), as well as increased WBC and neutrophil counts throughout the first week after stroke (P < .05). Correlation analysis revealed that neutrophil counts on D2 after LHI positively correlated with infarct and edema volumes measured from CT/MRI (R2  = 0.22 and R2  = 0.15, P < .01) and negatively correlated with Glasgow Coma Scale (ρ = -0.234, P < .05). Patients with D2 neutrophils > 7.14 × 109 /L had higher risk of brain herniation [odds ratio (OR) = 7.5, 95% CI: 2.0-28.1, P = .001], and patients with D2 neutrophils > 7.79 × 109 /L had a higher risk of death (OR = 5.8, 95% CI: 1.2-27.0, P = .015). CONCLUSION: Early peripheral neutrophil count after stroke relates to infarct size and the fatal outcome of LHI patients, which might help guiding acute LHI management such as reduction of intracranial pressure and potential antiinflammatory therapy in the future.


Assuntos
Infarto Encefálico/sangue , Infarto Encefálico/diagnóstico por imagem , Neutrófilos/metabolismo , Adulto , Idoso , Infarto Encefálico/mortalidade , Contagem de Células/métodos , Contagem de Células/tendências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
4.
Chin Med J (Engl) ; 132(19): 2300-2307, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31567479

RESUMO

BACKGROUND: Although the rehabilitation of aphasia has been extensively studied, the prediction of language outcome still has not received sufficient attention. The aim of this study was to predict the language outcome using mismatch negativity (MMN) in patients with large left-hemispheric infarction. METHODS: MMN was elicited by an oddball paradigm in which a standard tone (1000 Hz) and deviant tone (1500 Hz) were presented at 90% and 10% of the number of tones, respectively. The mean amplitudes and laterality indexes (LIs) of MMN were measured over the prefrontal, frontal, central, parietal, temporal, and perisylvian electrodes and both hemispheres during the first 7 days (session 1) and 10 to 20 days (session 2) post-onset. Mixed three-way analysis of variance (ANOVA) was used to investigate differences in these factors between two aphasia groups (the good recovery group and poor recovery group). The predictive value of the most significant LI was also compared with the score of National Institutes of Health Stroke Scale score and low-density volume on computed tomography. RESULTS: A total of 18 patients were enrolled in this study. Mixed three-way ANOVA showed no interaction effect of session × region of interest (ROI) × group (F [3.59, 57.38] = 1.301, P = 0.282) and no interaction effect of ROI × group (F [1.81, 29.01] = 0.71, P = 0.487) and session × group (F [1.00, 16.00] = 0.084, P = 0.776) for MMN amplitude. No interaction effect of session × ROI × group (F [1.79, 28.58] = 0.62, P = 0.530), but an interaction effect of session × group (F [1.00, 16.00] = 5.21, P = 0.036) was found for LIs. In the poor recovery group, the LIs of MMN over all the ROIs, except the parietal area, became more negative at session 2 than those at session 1 (P < 0.05), but this effect was not observed in the good recovery group. Additionally, significant differences were observed in the LIs at session 2 between the two groups (P < 0.05). The LI over the perisylvian area at session 2 had the highest predictive value with an area under the curve of 0.963 (95% confidence interval: 0.884-1.000). An LI score >-0.36 over the perisylvian area suggested good recovery, but a score <-0.36 suggested poor recovery. The LI cut-off value of -0.36 had the highest sensitivity (90.0%) and specificity (87.5%) for predicting a good language outcome at 3 months post-stroke. CONCLUSION: LIs of MMN amplitudes at approximately 2 weeks post left-hemisphere stroke serve as more sensitive predictors of language outcome, among which the LI over the perisylvian area exhibits the best predictive value.


Assuntos
Afasia/fisiopatologia , Infarto Cerebral/psicologia , Idioma , Idoso , Encéfalo/fisiopatologia , Infarto Cerebral/fisiopatologia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Neurofisiológica , Valor Preditivo dos Testes , Recuperação de Função Fisiológica
5.
Huan Jing Ke Xue ; 26(4): 13-7, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16212160

RESUMO

The contribution of anaerobic methane oxidation to the whole methane oxidation is investigated by monitoring the activities of anaerobic and aerobic oxidation of methane in paddy soils composed mechanically of <0.02 mm and > 0.02 mm soil granules, contained different water contents, and long-term fertilized organic manure or inorganic nitrogen, phosphorus and potassium fertilizers. The results obtained from various treated soils are relatively identical, which shows that most of the activities of anaerobic methane oxidation is obviously lower than those of aerobic methane oxidation. The contribution of anaerobic methane oxidation was generally lower than 10% of total methane oxidation in paddy soils with different treatments, however, higher than 30% in the soils emerged in water as the soils became anaerobic and methane diffused difficultly into soil, leading to lower activity of aerobic methane oxidation. The long-term fertilization has a significant effect on the activity of aerobic methane oxidation in paddy soil, with the / t / > t0.05, P < 0.05, but a slightly one with ( / t / < t 0.05, p > 0.05), leading to the obvious influence on the emission flux of methane. The contribution rates of anaerobic methane oxidation were lower from 1.31% to 4.14% in the whole methane oxidation.


Assuntos
Bactérias Anaeróbias/metabolismo , Metano/química , Oryza/crescimento & desenvolvimento , Solo/análise , Cromatografia Gasosa , Metano/análise , Oxirredução
6.
J Environ Sci (China) ; 14(3): 413-7, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12211995

RESUMO

This paper reports the influences of the herbicide butachlor (n-butoxymethl-chloro-2', 6'-diethylacetnilide) on microbial respiration, nitrogen fixation and nitrification, and on the activities of dehydrogenase and hydrogen peroxidase in paddy soil. The results showed that after application of butachlor with concentrations of 5.5 micrograms/g dried soil, 11.0 micrograms/g dried soil and 22.0 micrograms/g dried soil, the application of butachlor enhanced the activity of dehydrogenase at increasing concentrations. The soil dehydrogenase showed the highest activity on the 16th day after application of 22.0 micrograms/g dried soil of butachlor. The hydrogen peroxidase could be stimulated by butachlor. The soil respiration was depressed within a period from several days to more than 20 days, depending on concentrations of butachlor applied. Both the nitrogen fixation and nitrification were stimulated in the beginning but reduced greatly afterwards in paddy soil.


Assuntos
Acetanilidas/efeitos adversos , Herbicidas/efeitos adversos , Fixação de Nitrogênio/efeitos dos fármacos , Microbiologia do Solo , Agricultura , Oryza , Oxirredutases/farmacologia , Peroxidase/farmacologia
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