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1.
Heliyon ; 9(9): e19552, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809788

RESUMO

In the context of ecological civilization construction, cities are the main source of greenhouse gas emissions and thus they are key areas for dual-carbon construction. The dual-carbon community is the basic unit of the dual-carbon city and is essential for the promotion and construction of beautiful China. Guangzhou, as a historical and cultural city, is actively exploring the micro-renewal path of historical and cultural neighborhoods. In this paper we explore the micro-renewal process of the dual-carbon community and the Guangzhou Xiguan historical and cultural district, as well as their mutual relationship. In particular, we take the historical and cultural district of Guangzhou Xiguan Changhua Street as an example and explore its carbon emission characteristics based on the Intergovernmental Panel on Climate Change (IPCC) inventory compilation method. The carbon emission of this community in 2022 was determined as 3774670 kg, indicating the characteristics of low carbon emissions per capita but high energy consumption. Changhua Street provides a dual-carbon micro-renewal strategy and suggests a dual-carbon implementation path for the Guangzhou Xiguan historical and cultural district in the micro-renewal process.

2.
Inorg Chem ; 62(12): 4786-4798, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36926857

RESUMO

Four A2B-type CoIIIcorroles (2a-2d) with electron-donating/withdrawing substituents at the A2 meso-aryl substituents and a 4-(methylthio)phenyl ring at the B position have been synthesized and characterized, along with a series of meso-extended CoIIIcorroles (4a-4c) with 4'-(methylthio)biphenyl moieties. The electronic structures and structure-property relationships of the dyes have been analyzed by comparing their redox and optical properties to trends predicted in density functional theory calculations. Au electrodes surface-modified with 2a-2d and 4a-4c are highly efficient catalysts for electrocatalyzed hydrogen evolution reactions, and the electrocatalytic properties can be readily modulated by fine-tuning the electronic structure of the CoIIIcorrole and the distance between the "Au-S" bond and CoIII center.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 257: 119764, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33848953

RESUMO

Hydrogen sulfide (H2S) played crucial roles in biological processes and daily life, and the abnormal level of H2S was associated with many physiological processes. In this paper, we designed and developed a dicyanomethylene-4H-chromene (DCM)-based near-infrared (NIR) fluorescent probe DCM-NO guided by theoretical calculation. The probe displayed excellent selectivity towards H2S with a fast response time (3 min) and low detection limit (fluorescence 25.3 nM/absorption 6.61 nM) in Hela cells and real water samples. Furthermore, the probe-doped solid sensing materials (test strips and nanofibrous films) exhibited specific visualization of H2S under ambient light or hand-held UV lamp, providing great potential for on-site and real-time application in environmental and biological systems.


Assuntos
Sulfeto de Hidrogênio , Nanofibras , Corantes Fluorescentes , Células HeLa , Humanos
4.
Psychol Med ; 51(1): 90-101, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685046

RESUMO

BACKGROUND: The microbiota-gut-brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients. METHODS: We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD. RESULTS: The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890. CONCLUSIONS: The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Microbioma Gastrointestinal , Triptofano/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade
5.
J Affect Disord ; 278: 311-319, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979562

RESUMO

BACKGROUND: The microbiome-gut-brain axis, especially the microbial tryptophan biosynthesis and metabolism pathway (MiTBamp), is closely connected to bipolar disorder with current major depressive episode (BPD). METHODS: We performed shotgun metagenomics sequencing (SMS) of faecal samples from 25 BPD patients and 28 healthy controls (HCs). Except for the microbiota taxa and MiTBamp analyses, we also built a classification model using the Random Forests (RF) and Boruta algorithm to find the microbial biomarkers for BPD. RESULTS: Compared to HCs, the phylum Bacteroidetes abundance was significantly reduced, whereas that of the Actinobacteria and Firmicutes were significantly increased in BPD patients. We also identified 38 species increased and 6 species decreased significantly in the BPD group. In the MiTBamp, we identified that two Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K00658 and K00837) were significantly lower in the BPD, and five KOs (K01696, K00382, K00626, K01667, and K03781) were significantly higher in the BPD group. We also identified significant genera and species which were closely related to these KOs. Finally, RF classification based on gut microbiota at the genus level can achieve an area under the receiver operating characteristic curve of 0.997. LIMITATIONS: The features of cross-sectional design, limited sample size, the heterogeneity of bipolar disorders, and a lack of serum/plasma tryptophan concentration measurements. CONCLUSIONS: The present findings enable a better understanding of changes in gastrointestinal microbiome and MiTBamp in BPD. Alterations of microbes may have potential as biomarkers for distinguishing the BPD patients form HCs.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Microbioma Gastrointestinal , Transtorno Bipolar/genética , Estudos Transversais , Transtorno Depressivo Maior/genética , Microbioma Gastrointestinal/genética , Humanos , Metagenômica , Triptofano
6.
BMC Psychiatry ; 19(1): 344, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694611

RESUMO

BACKGROUND: Electroconvulsive therapy (ECT) is the most rapid and effective treatment for patients with depression, ECT can achieve remarkable antidepressant effects in the initial 3-4 sessions, but significant side effects limit its use. However, recent low-charge electrotherapy (LCE) studies have demonstrated antidepressant or antipsychotic effects with significantly fewer side effects. The aim of this study is to propose a novel two-step charge set strategy for ECT treatment, referred to as Hybrid-ECT, to decrease side effects by using a low charge while preserving treatment efficacy. METHODS/DESIGN: A randomized, double-blinded, standard-controlled, parallel-group design will be carried out. We plan to enroll 112 inpatients diagnosed with depression (unipolar or bipolar) and randomly assign them to conventional ECT (control group) or to Hybrid-ECT (treatment group, 3 ECT sessions followed by LCE sessions (approximately 2.8 joules per session)). We will evaluate participants across a wide variety of domains including clinical symptoms, cognitive, psychological and functional metrics. We will also perform magnetic resonance imaging (MRI) and event-related potential (ERPs) assessments during treatment to explore brain function differences between ECT and LCE. DISCUSSION: This research proposes a simple but completely novel ECT strategy that aims to rapidly relieve depressive symptoms and minimize side effects. The mechanism of ECT and LCE will be further discussed. TRIAL REGISTRATION: Chinese Clinical Trial Registry, Number: ChiCTR1900022905 (Registration date: April 30, 2019).


Assuntos
Depressão/terapia , Eletroconvulsoterapia/métodos , Adolescente , Adulto , Encéfalo/fisiopatologia , Depressão/fisiopatologia , Método Duplo-Cego , Eletroconvulsoterapia/efeitos adversos , Potenciais Evocados/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Adulto Jovem
7.
Psychiatry Res ; 272: 676-681, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30616140

RESUMO

A double-blind, randomised controlled pilot clinical trial was conducted to assess the potential effectiveness and safety of low-charge electrotherapy (LCE) for patients with schizophrenia. Bitemporal LCE (approximately 2.8 Joules) was administered three times a week. The Positive and Negative Syndrome Scale score was set as the outcome measure. Any adverse event (AE) was recorded. Three visits occurred at baseline, post-treatment, and after one month of follow-up. Twelve patients were randomised to the electroconvulsive therapy (ECT) group or LCE group (6 patients in each group). No patient withdrew during the study. The LCE group did not experience seizures during the trial. Patients in both groups showed significant improvements in clinical measures after treatment, and the reduction of all scale scores between the two groups was nonsignificant. The LCE group experienced significantly fewer AEs than the ECT group. Compared with ECT, LCE exerts similar antipsychotic effects while causing fewer AEs. Thus, LCE has the potential to be a safe and effective treatment for patients with schizophrenia, but further research is needed.


Assuntos
Terapia por Estimulação Elétrica , Esquizofrenia/terapia , Adulto , Método Duplo-Cego , Eletroconvulsoterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Dalton Trans ; 47(33): 11470-11476, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30070298

RESUMO

Enantioselective electrocatalysis of α-, ß-, γ- and δ-hexachlorocyclohexanes (HCHs) by tetrakis-pentafluorophenyl-Fe(iii)porphyrin is described. The first example of the combined use of electrochemical measurements and theoretical calculations to determine the mechanism of the enantioselective C-Cl bond cleavage of the electrocatalysis is reported. The electrochemical measurements demonstrate that the reactivity of the HCHs follows the order γ-HCH > α-HCH > δ-HCH > ß-HCH. Steric considerations and a molecular orbital theory approach can be used to rationalize the enantioselective nature of the catalysis based on the ease of approach of each Cl atom to the central Fe(i) ion and a consideration of the nodes on the C-Cl bonds that weaken these bonds in a manner that results in bond cleavage and the formation of an Fe-Cl bond.

9.
Org Lett ; 20(7): 1941-1944, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29522349

RESUMO

Oxidation of neo-N-confused phlorin 1 with excessive FeCl3 leads to regioselective ring opening, generating three linear tetrapyrroles, i.e., (10 Z,15 Z)-biladienone 2, (10 Z,15 E)-biladienone 3, and 19-methoxy (10 Z,15 E)-biladiene 4 with an overall yield of 88%. The coordination of these compounds with Zn(II) is affected by the inverted terminal pyrrolic unit, and the presence of the electron-withdrawing keto moiety. The structural identities were also clearly elucidated by the crystal structures of 3 and 4-Zn and were rationalized by DFT calculations.

10.
Dalton Trans ; 46(21): 6912-6920, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28504792

RESUMO

The synthesis of four low symmetry A2B type Cu(iii)triarylcorroles with meso-aryl substituents that provide electron donating (push) and withdrawing (pull) properties is reported, along with their structural characterization by NMR spectroscopy and X-ray crystallography. An analysis of the structure-property relationships in the optical and redox properties has been carried out by comparing their optical spectroscopy, electrochemistry, and spectroelectrochemistry to trends predicted in DFT and TD-DFT calculations. The results demonstrate that A2B type Cu(iii)triarylcorroles are highly efficient catalysts for electrocatalyzed hydrogen evolution reactions (HERs) and that their reactivity can be modulated by changing the nature of the B-position meso-substituent.

11.
Org Lett ; 19(3): 650-653, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28112522

RESUMO

By the acid-catalyzed [2 + 2] condensation, an unprecedented neo-N-confused phlorin (neo-NCphlorin 1) was successfully synthesized. By treating 1 with N-chlorosuccinimide, the corresponding chloro-substituted neo-NCphlorin (1-Cl) was obtained. The oxidization of 1 with FeCl3 afforded the neo-N-confused phlorinone (neo-NCphlorinone 2), which bears a relatively coplanar conformation, different from the highly distorted ones observed for 1 and 1-Cl. Notably, 2 shows striking long-wavelength absorption beyond 1300 nm upon addition of TBAF.

12.
Chempluschem ; 82(4): 598-606, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31961595

RESUMO

Four metalloporphyrin dimers linked by bridging amide-bonded xanthene moieties and that contain either MnIII , CoII , NiII , or CuII metal centers were synthesized. Various spectroscopic, electrochemical, and spectroelectrochemical methods were used to study trends in their properties. Their electronic structure and optical properties were analyzed through a comparison of the electronic absorption and magnetic circular dichroism (MCD) spectral data with the results of time-dependent (TD)-DFT calculations.

13.
Org Lett ; 18(19): 5046-5049, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27676364

RESUMO

By oxidation of an alternately N-confused bilane in CH2Cl2, a C-N fused tetrapyrrin was synthesized that bears a 5.5.5-tricyclic ring generated from an intramolecular C-N linkage. When CH3CN was used as the reaction medium, a multiply C-N-fused octapyrrolic dimer was also obtained that contained two 5.5.5.7.5-pentacyclic moieties and a bipyrrole unit generated from the intramolecular C-N linkage and intermolecular C-C linkage, respectively. This could be coordinated with Ni(acac)2 to afford a mixed-ligand complex.

14.
Dalton Trans ; 44(41): 18237-46, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26425817

RESUMO

A lipophilic and electron-rich phthalocyanine (α,α'-n-OC5H11)8-H2Pc and its nickel(ii) complex (α,α'-n-OC5H11)8-Ni(ii)Pc have been synthesized and characterized. Detailed analyses of the electronic structure were carried out by spectroscopy, electrochemistry, spectroelectrochemistry, and TD-DFT calculations. A series of experiments demonstrate that the (α,α'-n-OC5H11)8-Ni(ii)Pc complex can be used as a catalyst for highly efficient carbonyl reductions.

15.
Epilepsy Res ; 108(6): 1052-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24794827

RESUMO

Previous studies have attempted to confirm the association between the ABCB1-C3435T polymorphism and drug-resistant epilepsy and produced discordant findings. A meta-analysis was conducted to assess the role of the C3435T polymorphism in drug-resistance in epilepsy. Databases were obtained from PubMed, Embase, the Chinese Wanfang, CNKI, and Chongqing VIP database, and all relevant studies were compiled up to February 2013. Odds ratios (ORs) were calculated using models of both fixed- and random-effects for comparisons of alleles and genotypes. Subgroup meta-analyses were carried out based on epilepsy subtype, age, therapeutic regimen, definition of drug-responsiveness and drug-resistance using alleles and genotypes models. Publication bias was tested by Begg's test and inverted funnel plot, and heterogeneity was checked by Cochran's Q statistic and the inconsistency index (I2). Cumulative meta-analyses were adopted to test the robustness of the findings. A total of 38 association studies including a total of 8716 subjects, 4037 drug-resistant patients and 4679 drug-responsive epilepsy patients were pooled in this meta-analysis. The association of ABCB1-C3435T with risk of drug-resistance was significant in the overall population (T allele vs. C allele, OR: 1.21; 95%CI: 1.06-1.39; P=0.006) and in Caucasians, adults, groups treated with various drugs, a '>10 seizures in a year' group based on resistance and a '≥2 years seizure free' group based on response subgroup analysis. The ABCB1-C3435T polymorphism is likely to act as a risk factor for resistance to antiepileptic drugs that needs to be confirmed through further studies.


Assuntos
Anticonvulsivantes/uso terapêutico , Resistência a Medicamentos/genética , Epilepsia/tratamento farmacológico , Epilepsia/genética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adolescente , Adulto , Fatores Etários , Povo Asiático/genética , Biomarcadores Farmacológicos , Criança , Bases de Dados Genéticas , Genótipo , Humanos , Pessoa de Meia-Idade , Fatores de Risco , População Branca/genética , Adulto Jovem
16.
Int J Neurosci ; 124(11): 841-51, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24397542

RESUMO

BACKGROUND: The role of genetic variants in the pathogenesis of stroke has not been fully elucidated. Several studies have been examined the association of the Integrin alpha2 (ITGA2) gene-C807T (rs1126643) polymorphism with ischemic stroke susceptibility. However, the results of these studies are inconsistent. In order to explore this association more deeply, we performed a meta-analysis. METHODS: We collected case-control studies concerning the relationship between the C807T polymorphism and ischemic stroke, and odd ratios (OR) with corresponding 95% confidence intervals (CI) were used to describe the relationships. Inconsistency index (I(2)) and Cochran's Q statistic were used to check heterogeneity. Publication bias was tested by funnel plots and Egger's test. RESULTS: Fifteen studies with 2242 cases and 2408 controls were included. Our meta-analysis results indicated an association between the C807T polymorphism and the risk of ischemic stroke in the overall population, Asians and the subgroup of hospital-based people. However, statistically association was not observed for Caucasians and non-hospitalized individuals. CONCLUSIONS: The ITGA2 gene C807T polymorphism may be a susceptible predictor of the risk of ischemic stroke. More data are needed to elucidate the relationship further.


Assuntos
Isquemia Encefálica/genética , Predisposição Genética para Doença/genética , Integrina alfa2/genética , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , Povo Asiático/genética , Isquemia Encefálica/complicações , Estudos de Casos e Controles , Estudos de Associação Genética , Hospitalização/estatística & dados numéricos , Humanos , Viés de Publicação/estatística & dados numéricos , Acidente Vascular Cerebral/complicações , População Branca/genética
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(6): 654-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25556742

RESUMO

OBJECTIVE: To evaluate the effect of bone morphogenetic protein(BMP7)on the differentiation of adipose derived mesenchymal stem cells(AD-MSCs)isolated from different adipose tissues into brown adipocytes in rats. METHODS: Primary AD-MSCs were isolated from rate interscapular brown adipose tissue(iBAT),inguinal subcutaneous white adipose tissue(sWAT),and epididymal white adipose tissue(eWAT),respectively,and then cultivated in vitro. Differentiation of AD-MSCs into brown adipocytes was induced by BMP7. The characteristics of brown adipocytes were detected by immunofluorescence staining and oil red staining of cells. The expression levels of brown adipocyte-related genes were detected by polymerase chain reaction. RESULTS: AD-MSCs from iBAT and sWAT were differentiated into cluster multilocular cells,which were stained red by oil red "O"staining and showed uncoupling protein 1-positive by immunofluorescent staining method. AD-MSCs from eWAT had a small number of scattered multilocular cells and showed uncoupling protein 1-negative. The results of reverse transcription-polymerase chain reaction showed that the uncoupling protein 1 gene was highly expressed in the iBAT group and sWAT group but was negative in the eWAT group. CONCLUSION: AD-MSCs isolated from different adipose tissues in rats have different gene expression profiles and differentiation potentials.


Assuntos
Adipócitos Marrons/fisiologia , Tecido Adiposo Marrom/fisiologia , Proteína Morfogenética Óssea 7/metabolismo , Diferenciação Celular/fisiologia , Células-Tronco Mesenquimais/fisiologia , Tecido Adiposo/metabolismo , Animais , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Obesidade/metabolismo , Ratos , Proteína Desacopladora 1
18.
Int J Endocrinol ; 2013: 753150, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24288530

RESUMO

Diabetes mellitus (DM) is one of the primary causes of premature death and disability worldwide. We performed a systematic review and meta-analysis of the published literature regarding the trends in prevalence, awareness, treatment, and control of diabetes mellitus in mainland China. PUBMED, EMBASE, Chinese Biomedical Database, China National Infrastructure database, Chinese Wan Fang database, and Chongqing VIP database were searched. Fifty-six eligible studies were included. Increasing trends in the prevalence, treatment, and control of diabetes in mainland China from 1979 to 2012 were observed. The pooled prevalence, awareness, treatment, and control of diabetes mellitus were 6.41%, 45.81%, 42.54%, and 20.87%, respectively. A higher prevalence of diabetes mellitus was found in urban (7.48%, 95%CI = 5.45~9.50) than rural (6.53%, 95%CI = 4.30~8.76) areas. Furthermore, an increasing chronological tendency was shown in different subgroups of age with regard to the prevalence of diabetes. A higher awareness of DM was found in urban (44.25%, 95%CI = 32.60~55.90) than rural (34.27%, 95%CI = 21.00~47.54) populations, and no significant differences were found in the treatment, and control of diabetes among the subgroups stratified by gender and location. From 1979 to 2012, the prevalence, treatment, and control of diabetes mellitus increased; nevertheless, there was no obvious improvement in the awareness of diabetes.

19.
Nanotechnology ; 24(11): 115603, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23448977

RESUMO

With a unique structure and extraordinary properties, graphene has attracted tremendous attention in the preparation of graphene-based composites for various applications. In this study, two different strategies, including in situ growth and a self-assembly approach, have been developed to load CeO2 nanoparticles onto reduced graphene oxide (RGO) nanosheets. The microstructure and morphology of the as-synthesized RGO/CeO2 nanocomposites were investigated by x-ray diffraction, Raman spectroscopy and transmission electron microscopy. The results reveal that CeO2 nanoparticles with well-controlled size and a uniform distribution on RGO sheets with tunable density can be achieved through the self-assembly approach. The significantly enhanced photocatalytic activity of the RGO/CeO2 nanocomposites in comparison with bare CeO2 nanoparticles was revealed by the degradation of methylene blue under simulated sunlight irradiation, which can be attributed to the improved separation of electron-hole pairs and enhanced adsorption performance due to the presence of RGO. A suitable loading content of CeO2 on RGO was found to be crucial for optimizing the photocatalytic activity of the nanocomposites. It is expected that this convenient assembly approach with high controllability can be extended to the attachment of other functional nanoparticles to RGO sheets, and the resultant RGO-supported highly dispersed nanoparticles are attractive for catalysis, sensing and power source applications.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(10): 2736-9, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24409727

RESUMO

The functional complex Mn-TCPP-CS20 as a potential magnetic resonance imaging (MRI) contrast agent was synthesized through tetra(4-carboxyphenyl) Mn(II)-porphyrin (Mn-TCPP) modified by CS20, which was low degree of polymerization and narrow distribution. The results showed that Mn-TCPP-CS20 had good water-solubility and structural stability. The chemical structures of the products were characterized with Fourier transform infrared spectra (FTIR), UV-Vis spectra, mass spectrum (MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The results showed that Mn-TCPP was successfully linked to CS20 by an amide function. The relaxation properties in vitro of the functional complex Mn-TCPP-CS20 as the potential MRI contrast agent were preliminarily studied. It was found that the longitudinal relaxivity (r1) of the synthesized Mn-TCPP-CS20 (6.11 mmol(-1) x L x s(-1)) was higher than that of the commercial contrast agent Gd-DTPA (r1 = 3.59 mmol(-1) x L x s(-1)). Besides, the imaging effect of Mn-TCPP-CS20 was superior to that of Gd-DTPA in the same condition. These studies suggested that Mn-TCPP-CS20 has the advantage of becoming a potential tissue-targeting contrast agent.


Assuntos
Quitosana/química , Imageamento por Ressonância Magnética , Metaloporfirinas/química , Meios de Contraste/química , Gadolínio DTPA , Peso Molecular
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