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1.
Zhen Ci Yan Jiu ; 46(9): 742-50, 2021 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-34558239

RESUMO

OBJECTIVE: To observe the effect of Mongolian medicine three-acupoints balance needling on the expression of p11/tPA/BDNF pathway and miRNA-16 in the hippocampus and middle raphe nucleus (MRN) in chronic stress depression model rats, so as to explore its mechanisms underlying improvement of depression. METHODS: Male SD rats were randomly divided into blank control, model, medication and Mongolian medicine acupuncture (acupuncture) groups, with 12 rats in each group. The depression model was established by using chronic unpredictable mild stress method. The rats in the medication group received gavage of prozac (2 mg/kg, diluted with normal saline, 1 mg/mL) 1 h after stress stimulation, once per day for 28 days, and those in the acupuncture group received three-acupoints (Heyi, Badagan and Xin) needling, once a day for 28 days. The behavioral changes were detected by using open field test and sugar consumption test before modeling and after the intervention. The immunoactivity of p11 and tPA proteins in the MRN, and their expression levels in both the MRN and hippocampus were detected by using immunofluorescence histochemistry and Western blot, separately, and the expression levels of miRNA-16 and BDNF mRNA in the hippocampus and MRN detected by using real-time quantitative PCR. RESULTS: After modeling, the crossing and rearing scores of open field tests and the relative consumption of sucrose in the model group were apparently lower than those of the blank control group (P<0.05), the expression levels of p11 and tPA in the MRN, and those of p11 and tPA proteins and BDNF mRNA in the MRN and hippocampus were significantly down-regulated (P<0.05), while those of miRNA-16 in the hippocampus and MRN were significantly up-regulated (P<0.05). Compared with the model group, the crossing and rearing scores of open field tests and glucose consumption, as well as the expression levels of p11 and tPA proteins and BDNF mRNA in the hippocampus and MRN were obviously increased in both the medication and acupuncture groups (P<0.05), while the expression of miRNA-16 in hippocampus was markedly down-regulated in both the medication and acupuncture groups (P<0.05). No significant differences were found between the acupuncture and medication groups in all the indexes mentioned above (P>0.05). CONCLUSION: Mongolian medicine three-acupoints balance needling can improve the depressive state in depression rats, which may be associated with its effects in up-regulating the expression of p11 and tPA proteins and BDNF mRNA in the hippocampus and MRN and in down-regulating miRNA-16 in the hippocampus, suggesting an involvement of miRNA-16 controlled p11/tPA/BDNF signaling pathway in the antidepressant effect of acupuncture.


Assuntos
Pontos de Acupuntura , MicroRNAs , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão/genética , Depressão/terapia , Núcleo Dorsal da Rafe , Hipocampo , Masculino , Medicina Tradicional da Mongólia , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley
2.
ACS Appl Mater Interfaces ; 9(50): 43920-43938, 2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29171751

RESUMO

The traditional approach toward improving the crystallization rate as well as the mechanical and barrier properties of poly(lactic acid) (PLA) is the incorporation of nanocelluloses (NCs). Unfortunately, little study has been focused on the influence of the differences in NC morphology and dimensions on the PLA property enhancement. Here, by HCOOH/HCl hydrolysis of lyocell fibers, microcrystalline cellulose (MCC), and ginger fibers, we unveil the preparation of cellulose nanospheres (CNS), rod-like cellulose nanocrystals (CNC), and cellulose nanofibers (CNF) with different aspect ratios, respectively. All the NC surfaces were chemically modified by Fischer esterification with hydrophobic formate groups to improve the NC dispersion in the PLA matrix. This study systematically compared CNS, CNC, and CNF as reinforcing agents to induce different kinds of heterogeneous nucleation and reinforce the effects on the properties of PLA. The incorporation of three NCs can greatly improve the PLA crystallization ability, thermal stability, and mechanical strength of nanocomposites. At the same NC loading level, the PLA/CNS showed the highest crystallinity (19.8 ± 0.4%) with a smaller spherulite size (33 ± 1.5 µm), indicating that CNS, with its high specific surface area, can induce a stronger heterogeneous nucleation effect on the PLA crystallization than CNC or CNF. Instead, compared to PLA, the PLA/CNF nanocomposites gave the largest Young's modulus increase of 350 %, due to the larger aspect ratio/rigidity of CNF and their interlocking or percolation network caused by filler-matrix interfacial bonds. Furthermore, taking these factors of hydrogen bonding interaction, increased crystallinity, and interfacial tortuosity into account, the PLA/CNC nanocomposite films showed the best barrier property against water vapor and lowest migration levels in two liquid food simulates (well below 60 mg kg-1 for required overall migration in packaging) than CNS- and CNF-based films. This comparative study was very beneficial for selecting reasonable nanocelluloses as nucleation/reinforcing agents in robust-barrier packaging biomaterials with outstanding mechanical and thermal performance.

3.
Carbohydr Polym ; 176: 38-49, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28927621

RESUMO

Fabrication and characterization of bbiodegradable nanocomposites based on poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix reinforced with cellulose nanocrystal (CNC)-ZnO nanohybrids via simple solution casting for possible use as antibacterial biomedical materials is reported. The obtained nanocomposites exhibited an excellent antibacterial ratio of 95.2-100% for both types of bacteria namely S. aureus and E. coli and showed 9-15% degradation after one week. The addition of CNC-ZnO showed a positive effect on hydrophilicity and barrier properties. More significantly, the nanocomposites with 10wt% CNC-ZnO showed enhancement in tensile strength (140.2%), Young's modulus (183.1%), and the maximum decomposition temperature (Tmax) value increased by 26.1°C. Moreover, this study has provided a possible mechanism for using such nanofillers on the hydrolytic degradation of PHBV, which was beneficial to obtain the high-performance nanocomposites with modulated degradation rate for antibacterial biomaterials.

4.
Chinese Journal of Cardiology ; (12): 536-540, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-243737

RESUMO

<p><b>OBJECTIVE</b>To investigate the value of ischemic myocardial viability assessment using interleaved T1-T2* magnetic resonance imaging.</p><p><b>METHODS</b>The left anterior descending coronary arteries (LAD) were occluded for 2 hours, followed by 1-hour reperfusion in 7 pigs. The hearts were then removed and perfused with a mixture of pig blood and crystalloid solution in 1:1 ratio. T1 relaxation times of the myocardium were measured with a TurboFLASH inversion-recovery sequence. The contrast agent, Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) was then injected as a bolus into the aortic perfusion line (0.05 mmol/kg body wt). The first pass of the contrast agent through the heart was followed using the interleaved T1-T2* imaging sequence. Once the concentration of Gd-DTPA was in an equilibrium state, T1 relaxation times were measured again.</p><p><b>RESULTS</b>The percentage recovery of T2* intensity (PRT2*) at the maximum T1 intensity measured during the first pass of the contrast agent with the interleaved T1-T2* imaging was statistically different in normal myocardium (37 +/- 11)%, infarct rim (90 +/- 15)% and infarct core (100 +/- 5)%, F = 66.585, P = 0.000. Moreover, the infarcted regions shown on PR(T2)* maps matched well with the infarcted myocardium measured by TTC staining. The median of T(1) relaxation time in normal region, infarct rim and infarct core was 531 ms, 541 ms and 1298 ms, respectively (H = 6.284, P = 0.043). However, normal region could not be differentiated from infarct rim with T1 relaxation times (q = 0.082, P = 0.775).</p><p><b>CONCLUSION</b>Infarcted myocardium and ischemic myocardial viability can be correctly identified and evaluated by the interleaved T1-T2* magnetic resonance imaging in this model.</p>


Assuntos
Animais , Feminino , Masculino , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Métodos , Contração Miocárdica , Infarto do Miocárdio , Diagnóstico , Isquemia Miocárdica , Diagnóstico , Miocárdio , Patologia , Suínos
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