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PURPOSE OF THE STUDY: granulocyte-colony stimulating factor (G-CSF) is a hematopoietic growth factor existing in neutrophils, glial cells and neurons. Increasing researches discovered that G-CSF improved cell survival in neurodegenerative diseases by its anti-inflammatory effect. However, the effect of G-CSF in suppressing inflammation in Parkinson's disease (PD) remains unclear. Thus, the purpose of this study is to explored the anti-inflammatory effect of G-CSF in mouse model of PD. MATERIALS AND METHODS: G-CSF was administrated in the PD model induced by MPTP. Subsequently, the protein of tyrosine hydroxylase (TH), ionized calcium-binding adaptor molecule 1 (Iba-1) and the inflammatory cytokines including tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) in the midbrain were examined. In addition, the phosphorylated mitogen-activated protein kinases (MAPK) including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38 MAPK in the midbrain were investigated. RESULTS: Compared with the MPTP group, the protein of TH in the midbrain was increased, while the Iba-1 and the inflammatory factors were decreased. In addition, the expression of phosphorylated JNK (p-JNK) in the midbrain of the MPTP + G-CSF group was decreased, while the phosphorylated ERK (p-ERK) levels were elevated. CONCLUSIONS: These findings emphasize that G-CSF inhibited the degradation of DA neurons. The protective effect is associated with the reduction of the inflammatory factors caused by the inhibition of the microglial activation. Moreover, G-CSF may decrease the inflammatory factors through the decrease of P-JNK and the increase of P-ERK.
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Enfermedad de Parkinson , Factor de Necrosis Tumoral alfa , Ratones , Animales , Enfermedad de Parkinson/tratamiento farmacológico , Interleucina-1beta , Neuronas Dopaminérgicas , Factor Estimulante de Colonias de Granulocitos/farmacología , Quinasas MAP Reguladas por Señal Extracelular , Antiinflamatorios/farmacología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacologíaRESUMEN
OBJECTIVES: To systematically evaluate the efficacy and safety of noninvasive high-frequency oscillatory ventilation (NHFOV) versus nasal intermittent positive pressure ventilation (NIPPV) as post-extubation respiratory support in preterm infants. METHODS: China National Knowledge Infrastructure, Wanfang Data, Chinese Journal Full-text Database, China Biology Medicine disc, PubMed, Web of Science, and the Cochrane Library were searched for articles on NHFOV and NIPPV as post-extubation respiratory support in preterm infants published up to August 31, 2022. RevMan 5.4 software and Stata 17.0 software were used for a Meta analysis to compare related indices between the NHFOV and NIPPV groups, including reintubation rate within 72 hours after extubation, partial pressure of carbon dioxide (PCO2) at 6-24 hours after switch to noninvasive assisted ventilation, and the incidence rates of bronchopulmonary dysplasia (BPD), air leak, nasal damage, periventricular leukomalacia (PVL), intraventricular hemorrhage (IVH), and retinopathy of prematurity (ROP). RESULTS: A total of 9 randomized controlled trials were included. The Meta analysis showed that compared with the NIPPV group, the NHFOV group had significantly lower reintubation rate within 72 hours after extubation (RR=0.67, 95%CI: 0.52-0.88, P=0.003) and PCO2 at 6-24 hours after switch to noninvasive assisted ventilation (MD=-4.12, 95%CI: -6.12 to -2.13, P<0.001). There was no significant difference between the two groups in the incidence rates of complications such as BPD, air leak, nasal damage, PVL, IVH, and ROP (P>0.05). CONCLUSIONS: Compared with NIPPV, NHFOV can effectively remove CO2 and reduce the risk of reintubation, without increasing the incidence of complications such as BPD, air leak, nasal damage, PVL, and IVH, and therefore, it can be used as a sequential respiratory support mode for preterm infants after extubation.
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Displasia Broncopulmonar , Ventilación de Alta Frecuencia , Ventilación no Invasiva , Síndrome de Dificultad Respiratoria del Recién Nacido , Lactante , Recién Nacido , Humanos , Recien Nacido Prematuro , Ventilación con Presión Positiva Intermitente , Extubación Traqueal , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Presión de las Vías Aéreas Positiva ContínuaRESUMEN
ZnO/Zn hybrid nanostructures including nanowires and nanonets were induced on a Zn foil by using 400-nm femtosecond (fs) laser pulses with a low repetition rate of 1 kHz and duration of 100 fs. The laser fluence was chosen to be slightly above the ablation threshold of Zn. The luminescence of the formed ZnO/Zn hybrid nanostructures was examined by using fs laser pulses with a high repetition rate of 76 MHz and duration of ~130 fs through both single-photon and multiphoton excitation. While the luminescence spectrum under the single-photon excitation exhibited a single peak at ~480 nm, a broadband upconversion luminescence with many ripples was observed under the multiphoton excitation. More interestingly, the upconversion luminescence of the ZnO/Zn hybrid nanostructures was significantly enhanced by the underlying Zn nanostructures which induced strongly localized electric field. The enhancement of the upconversion luminescence was verified by the short lifetime of only ~79 ps observed for the ZnO/Zn hybrid nanostructures, which is nearly one order of magnitude smaller as compared with the luminescence lifetime of the ZnO nanorods synthesized by using the chemical coprecipitation method. The localization of electric field in the ZnO/Zn hybrid nanostructures was confirmed by the numerical simulations based the finite-difference time-domain technique.
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Periodic surface structures with periods as small as about one-tenth of the irradiating femtosecond (fs) laser light wavelength were created on the surface of a titanium (Ti) foil by exploiting laser-induced oxidation and third harmonic generation (THG). They were achieved by using 100-fs laser pulses with a repetition rate of 1 kHz and a wavelength ranging from 1.4 to 2.2 µm. It was revealed that an extremely thin TixOy layer was formed on the surface of the Ti foil after irradiating fs laser light with a fluence smaller than the ablation threshold of Ti, leading to a significant enhancement in THG which may exceed the ablation threshold of TixOy. As compared with Ti, the maximum efficacy factor for TixOy appears at a larger normalized wavevector in the direction perpendicular to the polarization of the fs laser light. As a result, the THG-dominated laser ablation of TixOy induces 100-nm periodic structures parallel to the polarization of the fs laser light. The depth of the periodic structures was found to be ~10 nm by atomic force microscopy and the formation of the thin TixOy layer was verified by energy dispersive X-ray spectroscopy.
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Rayos Láser , Microscopía de Fuerza Atómica/instrumentación , Espectrometría por Rayos X/instrumentación , Titanio/química , Diseño de Equipo , Propiedades de SuperficieRESUMEN
Efficient three-photon luminescence (3PL) from a scintillating silicate glass co-doped with Gd(3+) and Tb(3+) was generated by using a focused femtosecond laser beam at 800 nm. Four emission bands centered at 496, 541, 583, and 620 nm were identified as the electronic transitions between the energy levels of Tb(3+) followed by three-photon absorption (3PA) in Gd(3+) and Tb(3+) and the resonant energy transfer from Gd(3+) to Tb(3+). More interestingly, a strong polarization dependence of the 3PL was observed and it is ascribed to the polarization dependent 3PA in Gd(3+) and Tb(3+) and/or the angular distribution of photogenerated electrons in the glass.
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The femtosecond laser ablation of silicon surface near the ablation threshold was investigated and the preferential ablation along different directions was observed in different stages. It was found that the ripples formed in the initial stage facilitate the ablation along the direction perpendicular to the ripples, leading to the formation of an elliptical ablation area. With increasing length and depth of the ripples, however, nanohole arrays formed in the ripples will modify the distribution of electric field which benefits the ablation along the direction parallel to the ripples. Consequently, the ablation area is gradually changed to a circular one after irradiating sufficient number of pulses.
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Rayos Láser , Nanopartículas/química , Nanopartículas/ultraestructura , Silicio/química , Silicio/efectos de la radiación , Nanopartículas/efectos de la radiación , Dosis de Radiación , Propiedades de Superficie/efectos de la radiaciónRESUMEN
The high spatial frequency periodic structures induced on metal surface by femtosecond laser pulses was investigated experimentally and numerically. It is suggested that the redistribution of the electric field on metal surface caused by the initially formed low spatial frequency periodic structures plays a crucial role in the creation of high spatial frequency periodic structures. The field intensity which is initially localized in the grooves becomes concentrated on the ridges in between the grooves when the depth of the grooves exceeds a critical value, leading to the ablation of the ridges in between the grooves and the formation of high spatial frequency periodic structures. The proposed formation process is supported by both the numerical simulations based on the finite-difference time-domain technique and the experimental results obtained on some metals such as stainless steel and nickel.
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Rayos Láser , Materiales Manufacturados , Níquel/química , Acero Inoxidable/química , Simulación por Computador , Análisis de Elementos Finitos , Microscopía Electrónica de Rastreo , Análisis Numérico Asistido por ComputadorRESUMEN
We report on the formation of one- and two-dimensional (1D and 2D) nanohole arrays on the surface of a silicon wafer by scanning with a femtosecond laser with appropriate power and speed. The underlying physical mechanism is revealed by numerical simulation based on the finite-difference time-domain technique. It is found that the length and depth of the initially formed gratings (or ripples) plays a crucial role in the generation of 1D or 2D nanohole arrays. The silicon surface decorated with such nanohole arrays can exhibit vivid structural colors through efficiently diffracting white light.
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A novel visible-light-induced 1,4-hydroxysulfonylation of vinyl enynes with sulfonyl chlorides has been established, providing a highly efficient protocol to access multisubstituted sulfonyl allenic alcohols. Control experiments and mechanistic studies disclose that the target products result from sequential reactions of hydroxyl and tosyl radicals, among which chloride anion plays a key role to generate the requisite â¢OH, thus bridging water and enynes. Moreover, the vinyl pendant is believed to decisively affect the site-selectivity of hydroxyl radical.
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The present study was conducted to investigate the clinical significance of caffeine and aminophylline in the treatment of premature infants with apnea under varying conditions of oxygen (O2) delivery. The clinical data of 120 premature infants with apnea treated with oxygen therapy and either caffeine citrate (20 mg/kg/day; n=77) or aminophylline (10 mg/kg/day; n=43) were retrospectively examined. The therapeutic performance of the drugs after the completion of the treatment was evaluated primarily according to the risk of recurrent episodes of apnea, the changes in the duration and concentration of inhaled O2 and the incidence of complications. In contrast to aminophylline, caffeine treatment significantly reduced the duration of O2 inhalation and the inhaled O2 concentration in the infants treated with mechanical ventilation or O2 delivery devices (P<0.05). Treatment with caffeine also decreased the incidence of recurrent apnea events and complications in the investigated population (P<0.05 or P<0.01). Caffeine performs better than aminophylline in the treatment of premature infants with apnea under different conditions of O2 delivery. The therapeutic performance of caffeine is achieved primarily via improving the efficacy of supplemental O2 and reducing the incidence of complications.
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A cascade alkynylation and selective hydrogenation catalyzed by covalent binaphthyl-stabilized palladium nanoparticles has been established, providing a novel and highly efficient methodology for accessing Z and Z,Z-selective phosphinyl [3]dendralenes with broad functional group tolerance and good yields. This strategy achieves the first cascade reactions of alkynylation and hydrogenation with chemoselectivity modulated by catalyst loading.
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Schwann cells (SCs) combined with acellular nerve allografts (ANAs) effectively promote the regeneration and repair of peripheral nerves, but the exact mechanism has not been fully elucidated. However, the disadvantages of SCs include their limited source and slow rate of expansion in vitro. Previous studies have found that adipose-derived stem cells have the ability to differentiate into Schwann-like cells. Therefore, we speculated that Schwann-like cells combined with ANAs could profoundly facilitate nerve regeneration and repair. The aim of the present study was to investigate the cellular and molecular mechanisms of regeneration and repair. In this study, tissue-engineered nerves were first constructed by adipose-derived Schwann-like cells and ANAs to bridge missing sciatic nerves. Then, the rats were randomly divided into five groups (nâ¯=â¯12 per group): a Control group; a Model group; an ADSC group; an SC-L group; and a DMEM group. Twelve weeks postsurgery, behavioral function tests and molecular biological techniques were used to evaluate the function of regenerated nerves and the relevant molecular mechanisms after sciatic nerve injury (SNI). The results showed that adipose-derived Schwann-like cells combined with ANAs markedly promoted sciatic nerve regeneration and repair. These findings also demonstrated that the expression of neurotrophic factors (NFs) was increased, and the expression of Janus activated kinase2 (JAK2)/P-JAK2, signal transducer and activator of transcription-3 (STAT3)/P-STAT3 was decreased in the spinal cord after SNI. Therefore, these results suggested that highly expressed NFs in the spinal cord could promote nerve regeneration and repair by inhibiting activation of the JAK2/STAT3 signaling pathway.
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Aloinjertos/trasplante , Janus Quinasa 2/fisiología , Regeneración Nerviosa/fisiología , Factor de Transcripción STAT3/fisiología , Nervio Ciático/fisiopatología , Animales , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Factor Neurotrófico Ciliar/biosíntesis , Masculino , Trasplante de Células Madre Mesenquimatosas/métodos , Factor de Crecimiento Nervioso/biosíntesis , Neuronas/trasplante , Ratas , Recuperación de la Función/fisiología , Nervio Ciático/lesiones , Nervio Ciático/cirugía , Transducción de Señal/fisiología , Médula Espinal/metabolismoRESUMEN
Tanshinone IIA is one of the major constituents of Salvia miltiorrhiza Bunge known as Danshen. Recent reports have shown that Tanshinone IIA has neuroprotective effects against cerebral ischemia/reperfusion injury and traumatic injury of the spinal cord in rats. However, whether Tanshinone IIA has any neuroprotective effect in Parkinson's disease remains unknown. In this study, we evaluated whether Tanshinone IIA promotes the survival of nigrostriatal dopaminergic (DA) neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson's disease. MPTP induced degeneration of nigrostriatal DA neurons and microglial activation as visualized by tyrosine hydroxylase and CD11b immunoreactivity. The results of Western blot and immunohistochemistry showed upregulation of NADPH oxidase and iNOS in the MPTP-treated substantia nigra pars compacta. Treatment with Tanshinone IIA prevented degeneration of nigrostriatal DA neurons and increased the level of striatal dopamine content. This neuroprotection afforded by Tanshinone IIA was associated with the suppression of microglial activation and reduced expression of NADPH oxidase and iNOS. The present findings show that Tanshinone IIA may possess anti-inflammatory and anti-oxidative properties and may have therapeutic value in the treatment of Parkinson's disease.