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1.
Gels ; 8(8)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35892718

RESUMO

Both sodium alginate and polyethyleneimine (PEI) have a good ability to adsorb heavy metal ions. PEI and sodium alginate were used as important precursors to synthesize positively charged carbon nanoparticles (p-CNDs) with hydroxyl and carboxyl, and negatively charged carbon nanoparticles (n-CNDs) with amino, respectively. The carbon nanoparticles (CNDs) aerogel with a large specific surface area and rich functional groups were constructed by self-assembled p-CNDs and n-CNDs via electrostatic attraction for adsorption of heavy metal ions in water. The results show that CNDs aerogel has good adsorption properties for Pb2+ (96%), Cu2+ (91%), Co2+ (86%), Ni2+ (82%), and Cd2+ (78%). Furthermore, the fluorescence emission intensity of CNDs aerogel will gradually decrease with the increase in the adsorption rate, indicating that it can detect the adsorption process synchronously. In addition, the cytotoxicity test reveals that CNDs have good biocompatibility and will not cause secondary damage to biological cells.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1933-1937, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839062

RESUMO

OBJECTIVE: To investigate the level of serum microRNA-609 and its clinical prognostic value in patients with thalassemia. METHODS: One hundred and twenty-seven patients with thalassemia treated in our hospital from April 2017 to April 2018 were selected, 100 healthy persons were selected as control group. The changes of miR-609 were analyzed by RT-PCR, the relationship between miR-609 and clinical indicators of thalassemia was analyzed, and the prognostic risk factors of thalassemia were evaluated by multivariate logistic regression analysis. RESULTS: The relative expression level of miR-609 in thalassemia patients was 3.17±0.24, which was significantly higher than that in control group (P<0.05). The levels of ALT, Plt and MCH in patients with high expression of miR-609 were significantly higher than those in patients with low expression of miR-609 (P<0.05). The levels of Hb and sICAM-1 in patients with high expression of miR-609 were significantly lower than those in patients with low expression of miR-609 (P<0.05). There was no correlation between the level of miR-609 and the patient's sex, age and AST (P>0.05). The incidence rate of mild anemia in high expression group was significantly lower than that in low expression group (P<0.05). There was no correlation between the level of miR-609 and the incidence rate of moderate anemia (P>0.05). The number of patients with severe anemia in the miR-609 high expression group was higher than that in miR-609 low expression group (P<0.05). The incidence rate of dizziness, fatigue and fever in patients with miR-609 high expression group was significantly higher than those in patients with miR-609 low expression (P<0.05). There was no correlation between the level of miR-609 and the incidence rate of nausea in patients with thalassemia. ROC curve showed that the AUC value of microRNA-609 was 0.862, the sensitivity was 83.6%, and the specificity was 84.1%, which suggested that miR-609 had a high diagnostic value for thalassemia. Multivariate logistic regression analysis showed that MCH and mir-609 were risk factors for poor prognosis of thalassemia patients. CONCLUSION: The increased level of serum miR-609 in patients with thalassemia is a risk factor for poor prognosis and can be used as a reference index for evaluating the efficacy for patients.


Assuntos
Talassemia , Biomarcadores Tumorais , Humanos , MicroRNAs , Prognóstico , Curva ROC , Talassemia/genética
3.
ISA Trans ; 84: 111-117, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30316571

RESUMO

The optimal modified performance of the multi-input multi-output (MIMO) networked control systems (NCSs) with encoding-decoding, channel noise in the forward channel and packet dropouts, quantization in the feedback channel is investigated in this paper. A new and efficient tracking performance index for the NCSs is presented which prevents variations in the tracking error where there is no integrator in the plant. The optimal modified performance is obtained by the method of coprime factorization and partial fraction. The results demonstrate that the optimal modified performance is related to the locations of the non-minimum phase (NMP) zeros, unstable poles of the given plant as well as their directions. In addition, the modified factor, packet dropouts probability, channel noise and encoding-decoding are also closely related to optimal modified performance of the NCSs. Finally, we present some particular examples to illustrate the theoretical results.

4.
Artigo em Inglês | MEDLINE | ID: mdl-24582336

RESUMO

In this paper, the photochemical and photobiological characters of the active radicals of berberine (BBR) was investigated for finding an efficient and safe photosensitizer with highly active transient products using in Photodynamic therapy (PDT) study. The active species of BBR was generated and identified by using pulse radiolysis method. In neutral aqueous solution, BBR react with hydrated electron and hydroxyl radical, forming the radical anion and neutral radical of BBR, and the related reaction rates were determined as 3.5×10(10) and 6.7×10(9) M(-1) s(-1), respectively. Further, the capability of BBR to photosensitize DNA cleavage was testified by laser flash photolysis (LFP) method, the results demonstrated that BBR neutral radical could react with guanine mononucleotide (K=1.9×10(9) M(-1) s(-1)) via electron transfer to give the guanine neutral radical. Additionally BBR selective cleavage single and double strand DNA at guanine moiety was observed. Finally, combining with the thermodynamic calculation, the possible photodamage mechanism of dGMP and DNA induced by BBR was clarified.


Assuntos
Berberina/química , Fotólise , Radiólise de Impulso , Absorção Fisico-Química , Animais , Ânions , Bovinos , DNA/química , Nucleotídeos de Desoxiguanina/química , Fármacos Fotossensibilizantes/química , Soluções
5.
Artigo em Inglês | MEDLINE | ID: mdl-22765939

RESUMO

In the present paper, the interaction between model protein lysozyme (Lys) and antitumorigenic berberine (BBR) was investigated by spectroscopic methods, for finding an efficient and safe photosensitizer with highly active transient products using in photodynamic therapy study. The fluorescence data shows that the binding of BBR could change the environment of the tryptophan (Trp) residues of Lys, and form a new complex. Static quenching is the main fluorescence quenching mechanism between Lys and BBR, and there is one binding site in Lys for BBR and the type of binding force between them was determined to be hydrophobic interaction. Furthermore, the possible interaction mechanism between BBR and Lys under the photoexcitation was studied by laser flash photolysis method, the results demonstrated that BBR neutral radicals (BBR(-H)) react with Trp (K=3.4×10(9)M(-1)s(-1)) via electron transfer to give the radical cation (Trp/NH(+)) and neutral radical of Trp (TrpN). Additionally BBR selectively oxidize the Trp residues of Lys was also observed by comparing the transient absorption spectra of their reaction products. Through thermodynamic calculation, the reaction mechanisms between (3)BBR and Trp or Lys were determined to be electron transfer process.


Assuntos
Berberina/metabolismo , Muramidase/metabolismo , Absorção , Berberina/química , Sítios de Ligação , Fluorescência , Cinética , Muramidase/química , Ligação Proteica , Espectrometria de Fluorescência , Triptofano/metabolismo
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(6): 1486-8, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20584697

RESUMO

OBJECTIVE: To study the effect of C5-siRNA on pathological changes after myocardial ischemia in rats. METHODS: Thirty healthy Sprague-Dawley rats were randomly divided into sham-operated group, ischemia group and C5-siRNA group. The cardiac ischemia models were established in ischemia group and C5-siRNA group by ligating the proximal end of the left anterior descending (LAD) coronary artery. The rats were infused with 100 microl/kg of C5-siRNA into myocardial tissue in C5-siRNA group and equal amount of normal saline in ischemia group and sham-operated group after ligating the LAD coronary artery for 30 min and then performed of ischemia for 4 hours. The cardiac index and left ventricular mass index were determined, morphological changes of myocardial tissue observed under optical microscope and the expression of C5 was detected by immunohistochemical staining and image analysis system. RESULTS: There were no statistically significant difference between the three groups in the left ventricular mass index and cardiac index in the rats after ischemia for 4 hours. Light microscopy indicated edema and degeneration of the myocardial tissue were milder in C5-siRNA group than in ischemia group, a small amount of red blood cells existed in the myocardial stroma of the former. The expression of C5 was increased more significantly in ischemia group and C5-siRNA group than in sham-operated group (P<0.001), but was decreased in C5-siRNA group more than in ischemia group with no statistically significant difference between the two groups (P=0.132). CONCLUSION: C5-siRNA could attenuate myocardial ischemia injury in rats by reducing inflammatory cell infiltration and expression of C5.


Assuntos
Complemento C5/genética , Isquemia Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , RNA Interferente Pequeno/genética , Receptor da Anafilatoxina C5a/genética , Animais , Masculino , Isquemia Miocárdica/patologia , Interferência de RNA , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 73(5): 955-9, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19482509

RESUMO

Using 266 nm laser flash photolysis it has been demonstrated that Berberine (BBR) in aqueous solution is ionized via a mono-photonic process giving a hydrated electron, anion radical that formed by hydrated electron react with steady state of BBR, and neutral radical that formed from rapid deprotonation of the radical cation of BBR. The quantum yield of photoionization is determined to be 0.03 at room temperature with KI solution used as a reference. Furthermore utilizing pH changing method and the SO(4.)(-) radical oxidation method, the assignment of radical cation of BBR was further confirmed, the pK(a) value of it was calculated, and the related set up rate constant was also determined.


Assuntos
Berberina/química , Fotólise , Elétrons , Radicais Livres , Íons/química , Lasers , Estrutura Molecular , Oxirredução , Espectrofotometria Ultravioleta , Sulfatos/química , Água/química
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