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1.
J Transl Med ; 22(1): 562, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867291

RESUMO

BACKGROUND: Intravitreal injections of angiogenesis inhibitors have proved efficacious in the majority of patients with ocular angiogenesis. However, one-fourth of all treated patients fail to derive benefits from intravitreal injections. tRNA-derived small RNA (tsRNA) emerges as a crucial class of non-coding RNA molecules, orchestrating key roles in the progression of human diseases by modulating multiple targets. Through our prior sequencing analyses and bioinformatics predictions, tRNA-Cys-5-0007 has shown as a potential regulator of ocular angiogenesis. This study endeavors to elucidate the precise role of tRNA-Cys-5-0007 in the context of ocular angiogenesis. METHODS: Quantitative reverse transcription PCR (qRT-PCR) assays were employed to detect tRNA-Cys-5-0007expression. EdU assays, sprouting assays, transwell assays, and Matrigel assays were conducted to elucidate the involvement of tRNA-Cys-5-0007 in endothelial angiogenic effects. STZ-induced diabetic model, OIR model, and laser-induced CNV model were utilized to replicate the pivotal features of ocular vascular diseases and evaluate the influence of tRNA-Cys-5-0007 on ocular angiogenesis and inflammatory responses. Bioinformatics analysis, luciferase activity assays, RNA pull-down assays, and in vitro studies were employed to elucidate the anti-angiogenic mechanism of tRNA-Cys-5-0007. Exosomal formulation was employed to enhance the synergistic anti-angiogenic and anti-inflammatory efficacy of tRNA-Cys-5-0007. RESULTS: tRNA-Cys-5-0007 expression was down-regulated under angiogenic conditions. Conversely, tRNA-Cys-5-0007 overexpression exhibited anti-angiogenic effects in retinal endothelial cells, as evidenced by reduced proliferation, sprouting, migration, and tube formation abilities. In diabetic, laser-induced CNV, and OIR models, tRNA-Cys-5-0007 overexpression led to decreased ocular vessel leakage, inhibited angiogenesis, and reduced ocular inflammation. Mechanistically, these effects were attributed to the targeting of vascular endothelial growth factor A (VEGFA) and TGF-ß1 by tRNA-Cys-5-0007. The utilization of an exosomal formulation further potentiated the synergistic anti-angiogenic and anti-inflammatory efficacy of tRNA-Cys-5-0007. CONCLUSIONS: Concurrent targeting of tRNA-Cys-5-0007 for anti-angiogenic and anti-inflammatory therapy holds promise for enhancing the effectiveness of current anti-angiogenic therapy.


Assuntos
Inibidores da Angiogênese , Anti-Inflamatórios , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Humanos , RNA de Transferência/metabolismo , RNA de Transferência/genética , Camundongos Endogâmicos C57BL , Proliferação de Células/efeitos dos fármacos , Neovascularização de Coroide/patologia , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/metabolismo , Masculino , Oftalmopatias/tratamento farmacológico , Oftalmopatias/patologia , Oftalmopatias/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Neovascularização Patológica , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/patologia , Retinopatia Diabética/metabolismo , Camundongos , Células Endoteliais da Veia Umbilical Humana/metabolismo
2.
Br J Clin Pharmacol ; 86(1): 85-92, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31656042

RESUMO

AIMS: Dexmedetomidine is highly specific α2-adrenoceptor agonist. A single bolus of dexmedetomidine can achieve clinical therapeutic effect. Therefore, it is essential to know the safety margin between the clinical effectiveness dosages of dexmedetomidine and its side effect. METHODS: A total of 42 patients who underwent elective thyroidectomy were enrolled in this study. Dexmedetomidine was given as a single bolus injection 30 min towards the end of surgery. The up-and-down sequential schedule was used in this study. The starting dose of dexmedetomidine was set at 0.1 µg/kg in the first patient and the next patient would then receive a dose of dexmedetomidine decremented by 0.05 µg/kg if the prior patient's baseline heart rate (HR) had a decrease of ≥20% and/or mean arterial blood pressure (MAP) increase or decrease of ≥20%, otherwise, the following patient would receive an incremental 0.05 µg/kg dose of dexmedetomidine. The analytic techniques of linear, linear-logarithmic, exponential regressions and centred isotonic regression were used to determine the ED50 of dexmedetomidine and the residual standard errors were calculated for the comparison of goodness of fit among the different models. RESULTS: The median (interquartile range [range]) lowest HR was 57 beats/min (53-63.3[46-76]) with an average HR decrease of 8.0 beats/min (5-13 [4 to 23]). The median (interquartile range [range]) highest MAP was 98 mmHg (91.8-105 [83-126]) with a MAP increase of 10.0 mmHg (6.8-18.0 [2-24]). The ED50 (95% confidence interval) from 4 different statistical approaches (linear, linear-logarithmic, exponential regressions and centred isotonic regression) were 0.262 µg/kg (0.243, 0.306), 0.252 µg/kg (0.238, 0.307), 0.283 µg/kg (0.238, 0.307), and 0.278 µg/kg, respectively. Among the 4 models, the exponential regression had the least residual standard error (0.03618). CONCLUSION: The ED50 derived from 4 statistical models for an intravenous bolus of dexmedetomidine without significant haemodynamic effects was distributed in a narrow range of 0.252-0.283 µg/kg, and the exponential regression was the model to best match the study data.


Assuntos
Dexmedetomidina , Adulto , Anestesia Geral , Frequência Cardíaca , Hemodinâmica , Humanos , Hipnóticos e Sedativos/farmacologia
3.
Ying Yong Sheng Tai Xue Bao ; 33(4): 909-914, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543041

RESUMO

Cosmic-ray neutron sensing (CRNS) method was recently used to monitor soil moisture in farmland. But its spatial representation and accuracy needs further study. A field experiment was carried out to evaluate the applicability of CRNS for monitoring soil moisture in winter wheat farmland of the North China Plain. The spatial weight of CRNS detector was simulated by the ultra rapid adaptable neutron-only simulation for environmental research (URANOS) model and the CRNS-estimated soil moisture was compared with the measured soil moisture. The results showed that the CRNS detection radius obtained by URANOS simulation was 127-139 m, and that the weight distribution showed good agreement with the theoretical value. The determination coefficient (R2) and the root-mean-square error (RMSE) between CRNS-estimated soil moisture and measured soil moisture reached 0.64 and 0.05 cm3·cm-3, respectively. The CRNS-estimated soil moisture was sensitive to the changes of overall moisture in the detection area, with seasonal variation of measurement accuracy. In conclusion, cosmic-ray neutron sensing is a continuous and reliable method for monitoring total water content in winter wheat fields.


Assuntos
Solo , Água , China , Fazendas , Nêutrons , Triticum , Água/análise
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3078-82, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242521

RESUMO

Wood/methylolurea composite was prepared with the in-situ polymerization. The green timber with high moisture content was impregnated by a pulse-dipping machine and then was dried in a hot-press drying kiln. The cross-linking reaction was taken under the heat treatment between the wood modifier and the wood composition, including cellulose, hemicelluloses, and lignin. The chemical composition was analyzed according to the Chinese standard, including X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR) and energy dispersive analysis of X-rays (EDXA). The changes in chemical composition of modified wood and carbon and nitrogen element were disused in the research The results showed that the content of water extraction and benzene alcohol extraction increased 187.43% and 230.87% respectively compared with the natural wood, while the lignin and holocellulose decreased 26.55% and 26.39% respectively. XPS showed that the concentrations of O and C atoms increased 9.4% and N element content increased 137.2%. 13C-NMR analysis showed that chemical reaction of the hydroxyl methyl urea with the hydroxyl in timber structure took place, with the reduction of hydroxyl content and increase in ether bond content. EDXA showed that the processing method can get impregnated modification wood and nitrogen element is evenly distributed in wood cell walls and intercellular space.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(4): 1083-6, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21714265

RESUMO

In the present research, the urea-formaldehyde prepolymer and multilayer hot-press drying were used to modify poplar plantation. The prepolymer was impregnated into cell lumen space by pulse-dipping machine. Then the timbers were compressed and dried by the multilayer hot-press drying kiln. The results showed that the physical and chemical properties of poplar were changed in this investigation. The basic density of modified wood increased 1.06 times compared with the natural wood, and the bending strength increased 33% for modified wood, compressive strength parallel to grain increased 74%, the water absorption decreased to 97% from 104%. The crystallinity decreased slightly from 39.65 to 36.89 because of the modifier impregnated. TGA analysis showed that the heat resistance of modified wood increased, the three exothermic peaks in DTA curve of modified wood were 280, 360 and 485 degrees C which were higher than natural wood in the corresponding position FTIR analysis showed that the hydroxyl modified material has a good association phenomenon, and carbonyl content decreased. The SEM spectrum showed the distribution of the prepolymer in the modified timber.


Assuntos
Teste de Materiais , Madeira , Força Compressiva , Temperatura Alta , Populus , Pressão , Água
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(5): 1216-9, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21800568

RESUMO

This article used hemicelluloses content in acacia spp. wood as a case study to demonstrate the influence of noise in the reference data on the results of NIR calibration model. The results indicated that the accuracy of NIR calibration model was affected by the reference data noise. The less noisy data was used in calibration model, the better result could be obtained. But when the noise was larger, NIR calibration model which was built by using regression mathematics methods can perform better than using primary reference data.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Madeira/análise , Acacia , Calibragem , Modelos Teóricos , Análise de Regressão
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(5): 1206-9, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20672602

RESUMO

In this research, hemicellulose contents of 78 wood meal samples of Acacia spp trees grown in Guangxi and another 33 wood meal samples of Acacia spp trees grown in Fujian were measured by wet chemistry. NIR spectra were also collected by a Bruker MPA spectrometer within 4 000-12 500 cm(-1) of wavenumbers using a standard sample cup. Equations were developed using partial least squares (PLS) regression and cross validation for multivariate calibration in this study. High coefficients of determination (R2) and low root mean square errors of cross-validation (RMSECV) were obtained for hemicellulose content (R2 = 0.947, RMSECV = 0.464) of Guangxi woodmeal samples. Prediction produced high correlation coefficients between laboratory and predicted values, with R2 and RMSEP values being 0.925 and 0.455, respectively. A variable numbers of Fujian samples ranging from one to thirteen were used to enhance the Guangxi calibration so as to be widely used for routine assessment of wood chemistry. It was demonstrated that the addition of a single Fujian sample to the Guangxi calibration set was sufficient to greatly reduce predictive errors and that the inclusion of 3 Fujian samples in the Guangxi set was sufficient to give relatively stable predictive errors. The R2 is 0.904 and RMSEP is 0.759. The addition of different sets of 3 Fujian samples to the Guangxi calibration, however, caused predictive errors to vary between sets.


Assuntos
Acacia/química , Polissacarídeos/análise , Calibragem , China , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao Infravermelho
8.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3804-3810, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833694

RESUMO

Pot experiment with winter wheat was conducted to investigate the effects of blended nitrogen (N) fertilizer (slow-release fertilizer-N:urea-N=1:1) combined with N fertilizer inhibitor NAM on soil ammonium (NH4+-N), nitrate (NO3--N), microbial biomass nitrogen (MBN) and fixed-ammonium (FN) contents. We analyzed dynamic characteristics of soil mineral N, MBN, FN pools under different treatments. There were six treatments, including no N fertilizer (CK), conventional urea (U), blended N fertilizer (MU), MU plus 2.5‰ NAM (MUN1), MU plus 5‰ NAM (MUN2), and MU plus 7.5‰ NAM (MUN3). Our results showed that, compared to that of MU treatment, MUN2 and MUN3 delayed the appearance time of NH4+-N peak. Averaged across the whole wheat growing period, soil mineral N content for NAM treatments decreased by 5.3%-11.7%. From tillering to maturity stage, MBN mineralization and mineralization rates were 38.96 mg·kg-1 and 91.5%, which was higher than that of U treatment; MBN mineralization and mineralization rates for MUN1, MUN2 and MUN3 treatments were 58.73 mg·kg-1, 83.3%, 94.20 mg·kg-1, 94.6%, 104.46 mg·kg-1 and 96.3%, respectively. The FA mineralization release for NAM treatments were higher by 2.83-9.19 mg·kg-1 than that of MU treatment. The results of path analysis showed that NAM addition weakened the direct effect of soil NH4+-N pool on NO3--N pool but enhanced the indirect effects of FN pool on NO3--N pool through affecting NH4+-N pool. The wheat grain yields of the MUN1, MUN2 and MUN3 treatments were significantly higher by 31.6%, 21.5% and 22.9% than that of MU treatment. Nitrogen use efficiencies were increased by 8.1%, 13.5% and 3.1%, respectively. In summary, through double regulation for N release and transformation in soil, NAM delayed the appearance time of soil NH4+-N peak and retarded its transformation into NO3--N, and increased the roles of MBN and FN in supplying N, thereby increased crop yield and N-fertilizer use efficiency.


Assuntos
Fertilizantes , Solo , Agricultura , Nitratos , Nitrogênio , Triticum
9.
Zhonghua Yi Xue Za Zhi ; 88(41): 2893-7, 2008 Nov 11.
Artigo em Chinês | MEDLINE | ID: mdl-19080093

RESUMO

OBJECTIVE: To investigate the therapeutic effects of alprostadil (Lipo-PGE1) and Ulinastatin on inflammatory response and lung injury after cardiopulmonary bypass (CPB) in pediatric patients with congenital heart diseases. METHODS: 58 children with congenital heart diseases, including atrial septal defect, ventricular septal defect, and atrioventricular septal defect, scheduled to undergo CPB, aged 4 - 72 months, were randomly divided into 4 groups: alprostadil Group P (n = 15) receiving alprostadil 10 ng/ml added into the prime solution and continuous pump infusion of alprostadil 10 ngxkg(-1)xmin(-1) via central vein until the end of operation, Group U (n = 15) receiving ulinastatin 20 000 U/kg divided into several doses to be added into the prime solution, Group PU (n = 14) receiving alprostadil and ulinastatin according to the above protocols, and Group C (control group, n = 14) receiving normal saline of the equal volume. Electrocardiogram (ECG), heart rate (HR), pulse oxygen saturation (SpO(2)), and mean arterial pressure (MAP) were continuously monitored during operation. Duration of mechanical ventilation and staying in ICU were also recorded. Plasma neutrophil (PMN), IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-alpha and matrix metalloproteinase (MMP-9) levels in the radial arterial blood samples were measured after induction of anesthesia before CPB (T(1)), 30 minutes and (T(2)), 2 hours (T(3)), 6 hours (T(4)), and 24 hours (T(5)) after the declamping of aorta. Inhaled oxygen concentration and arterial blood gas analysis were recorded at T(1), T(2), and T(3) for calculation of oxygenation index (OI). RESULTS: There were no significant differences in the MAP and HR among these four groups at any time points (all P > 0.05). The umbers of PMN and the levels of IL-6, IL-8, and TNF-alpha at T(2) and T(3) of Groups P, U, and PU were all significantly lower than that of Group C (all P < 0.05), with those of Group PU being the lowest. The IL-10 levels at T(2) and T(3) of Groups U and PU were significantly higher than that of Group C (both P < 0.05), the level of MMP-9 at T(2) and T(3) of Groups U and PU were significantly lower than that of Group C (all P < 0.05), however, there was not significant difference between Group P and Group C (P > 0.05). The OIs at T(2) of Groups P, U, and PU were significantly higher than that of Group C (all P < 0.05). The mechanical ventilation time of Groups P, U, and PU were all significantly shorter than that of Group C, and that of Group PU was significantly shorter than that of group C (P < 0.05). CONCLUSION: Decreasing the inflammatory response after CPB, alprostadil and ulinastatin used during CPB effectively reduce the pulmonary injury via inhibition of the neutrophil activation and cytokines release.


Assuntos
Reação de Fase Aguda/prevenção & controle , Alprostadil/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Ponte Cardiopulmonar , Glicoproteínas/uso terapêutico , Lesão Pulmonar/prevenção & controle , Reação de Fase Aguda/etiologia , Ponte Cardiopulmonar/efeitos adversos , Criança , Pré-Escolar , Citocinas , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lesão Pulmonar/etiologia , Masculino , Neutrófilos
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