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1.
Chem Sci ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39170716

RESUMO

The development of metal complexes for photosynthesis of hydrogen peroxide (H2O2) from pure water and oxygen using solar energy, especially in the absence of any additives (e.g., acid, co-catalysts, and sacrificial agents), is a worthwhile pursuit, yet still remains highly challenging. More importantly, the O2 evolution from the water oxidation reaction has been impeded by the classic bottleneck, the photon-flux-density problem of sunlight that could be attributed to rarefied solar radiation for a long time. Herein, we reported synthesis of boron dipyrromethene (BODIPY)-based cyclic trinuclear silver complexes (Ag-CTC), and they exhibited strong visible-light absorption ability, a suitable energy bandgap, excellent photochemical properties and efficient charge separation ability. The integration of BODIPY motifs as oxygen reduction reaction sites and silver ions as water oxidation reaction sites allows Ag-CTC to photosynthesize H2O2 either from pure water or from sea water in the absence of any additives with a high H2O2 production rate of 183.7 and 192.3 µM h-1, which is higher than that of other reported metal-based photocatalysts. The photocatalytic mechanism was systematically and ambiguously investigated by various experimental analyses and density functional theory (DFT) calculations. Our work represents an important breakthrough in developing a new Ag photocatalyst for the transformation of O2 into H2O2 and H2O into H2O2.

2.
Angew Chem Int Ed Engl ; 63(36): e202408186, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38895811

RESUMO

The development of novel metal-organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu-CTU-based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu-CTU to Ag-CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 µmol g-1 h-1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering.

3.
Regen Ther ; 25: 290-301, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38318480

RESUMO

Aim: This study aims to explore the mechanism of circ- AMOT-like protein 1 (Amotl1) in extracellular vesicles (Evs) derived from adipose-derived stromal cells (ADSCs) regulating SPARC translation in wound healing process. Methods: The morphology, wound healing rate of the wounds and Ki67 positive rate in mouse wound healing models were assessed by H&E staining and immunohistochemistry (IHC). The binding of IGF2BP2 and SPARC was verified by RNA pull-down. Adipose-derived stromal cells (ADSCs) were isolated and verified. The Evs from ADSCs (ADSC-Evs) were analyzed. Results: Overexpression of SPARC can promote the wound healing process in mouse models. IGF2BP2 can elevate SPARC expression to promote the proliferation and migration of HSFs. circ-Amotl1 in ADSC-Evs can increase SPARC expression by binding IGF2BP2 to promote the proliferation and migration of HSFs. Conclusion: ADSC-Evs derived circ-Amotl1 can bind IGF2BP2 to increase SPARC expression and further promote wound healing process.

4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(1): 105-109, 2023 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-36585012

RESUMO

OBJECTIVE: To explore the genetic basis, clinical phenotype and pathogenesis for a child with mosaicism ring chromosome 4. METHODS: Clinical data of the child was collected. Peripheral blood chromosomal karyotype G banding analysis, chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH) were carried out for the child, in addition with a review of the literature. RESULTS: The child was born full-term with low birth weight, facial dysmorphism, patent ductus arteriosus and ventricular septal defect. His karyotype was determined as mos46,XY,r(4)(p16.3q35.2)[259]/45,XY,-4[25]/47,XY,r(4)(p16.3q35.2), +r(4)(p16.3q35.2)[8]/46,XY,der(4)del(4)(p16.3)inv(4)(p16.3q31.1)[6]/46,XY,dic?r(4;4)(p16.3q35.2;p16.3q35.2)[4]/48,XY,r(4)(p16.3q35.2),+r(4)(p16.3q35.2)×2[3]/46,XY,r(4)(p1?q2?)[2]; CMA result was arr[GRCH37]4p16.3(68 345-2 981 614)×1; FISH result was 45,XY,-4[12]/45,XY,-4×2,+mar1.ish r1(4)(WHS-,D4Z1+)[1]/ 46,XY,-4,+mar1.ishr1(4)(WHS-,D4Z1+)[73]/46,XY,-4,+mar2.ishr2(4)(WHS-,D4Z1++)[1]/47,XY,-4,+mar1×2.ishr1(4) (WHS-, D4Z1+)×2[4]/46,XY,del(4)(p16.3).ish del(4)(p16.3)(WHS-,D4Z1+)[9]. CONCLUSION: In this case, the ring chromosome 4 as a de novo variant has produced a number of cell lines during embryonic development and given rise to mosaicism. The clinical phenotype of ring chromosome 4 is variable. The instability of the ring chromosome itself, presence of mosaicism, chromosome breakpoint and range of deletion and/or duplication may all affect the ultimate phenotype.


Assuntos
Cromossomos em Anel , Humanos , Gravidez , Feminino , Hibridização in Situ Fluorescente , Cariotipagem , Cariótipo , Mosaicismo
5.
Int J Ophthalmol ; 15(6): 894-904, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814901

RESUMO

AIM: To evaluate the effect of miRNA-451 on rhesus macaque choroid-retinal endothelial (RF/6A) cell function and proteome profile. METHODS: The RF/6A cells were transfected with miRNA-451 mimic and inhibitor. The role of miRNA-451 on proliferation ability was evaluated by CCK-8 assay. Furthermore, iTRAQ quantitative proteomic analysis was applied to comprehensively illuminate the change of cellular proteins and biological function between different groups. RESULTS: In miRNA-451 overexpression group, cell proliferation of RF/6A decreased both at 24h and 48h; while in miRNA-451 inhibition group, on the contrary, RF/6A cell proliferation was increased at 48h. Based on iTRAQ quantitative proteomic analysis, 23 differentially expressed proteins (DEPs) were detected in the comparison of miRNA-451 mimic and mimic control-transfected RF/6A cells, and 30 DEPs were identified in the comparison of RF/6A cells transfected with miRNA-451 inhibitor and inhibitor control. DEPs such as GORASP2, KRT1, SLC7A2, RIC8A, DDX42, CAP1, PCBP2 might be closely related to the inhibitory effect of miRNA-451 on RF/6A cell proliferation, while PCYT1A, MGAT1, TUBB, MCU, SIL1, BID, MSH6 might account for the positive effect of miRNA-451 inhibitor on RF/6A cell growth. PTPN1, as the only protein exhibiting an opposite trend between miRNA-451 mimic and inhibitor-transfected cells, was most likely accountable for the inhibition of miRNA-451 mimic on RF/6A cell growth, and the promotion of miRNA-451 inhibitor on RF/6A cell proliferation. CONCLUSION: miRNA-451 overexpression can suppress the growth of RF/6A cells while knockdown of miRNA-451 can promote RF/6A cell viability. Among all DEPs, increased PTPN1 is most likely to account for the negative regulation of miRNA-451 on RF/6A proliferation. miRNA-451 can be a protective factor for neovascular disease of fundus via regulating choroid retinal endothelial cell function.

6.
Ying Yong Sheng Tai Xue Bao ; 33(4): 1118-1124, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543067

RESUMO

To reveal the formation mechanism of fungal community and diversity during the production of Shaoxing Huangjiu, we examined fungal communities in the samples of Linfanjiumu, Maiqu and fermentation mash based on Illumina MiSeq PE300 high-throughput sequencing platform. A total of 136000, 215283, 166150, and 143624 sequences were obtained from the samples of Linfanjiumu, Maiqu, initial mash and mature mash, respectively. After clustering, 32, 133, 107 and 84 OUT (operational taxonomic units) were obtained, respectively. The diversity and richness of fungi were in order of Maiqu > initial mash > mature mash > Linfanjiumu. At the level of phylum, Ascomycota were dominant in all samples. At genus level, Saccharomyces was dominant in Linfanjiumu, Aspergillus was dominant in Maiqu, and Saccharomyces and Aspergillus were the dominant fungi in the initial and mature mash. With the extension of the fermentation time, the proportion of Saccharomyces gradually increased in the mash, while other fungal groups including Aspergillus showed a decreasing trend. According to the results of PCoA analysis and similarity cluster analysis, the structure of fungi community in Linfanjiumu, initial mash and mature mash was much similar, while the fungal resources in Maiqu were quite different from other samples. The analysis of fungal community characteristics in the initial mash showed that the Linfanjiumu and Maiqu affected fungal diversity in Shaoxing Huangjiu. The dominant species of saccharification and fermentation starter (Linfanjiumu and Maiqu) played a leading role in driving community assembly of fermentation fungi.


Assuntos
Ascomicetos , Micobioma , Vinho , Fermentação , Fungos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Vinho/microbiologia
7.
Dalton Trans ; 50(25): 8736-8745, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34079971

RESUMO

A family of cyano-bridged 3d-4f 1D chain compounds, {RE[TM(CN)6(2-PNO)5]}·(H2O)4 {RE = YIII, TM = [FeIII]LS (1); RE = DyIII, TM = CoIII (3); RE = ErIII, TM = [FeIII]LS (4), CoIII (5); 2-PNO = 2-picoline-N-oxide} and {RE[TM(CN)6(2-PNO)5]} {RE = DyIII, TM = [FeIII]LS (2)}, were synthesized and characterized. Single-crystal X-ray diffraction studies reveal that compounds 1 and 3-5 are isostructural, while compound 2 has a similar 1D chain structure with a different chain to chain arrangement. An axially-elongated pentagonal bipyramidal (D5h) coordination geometry is formed with five 2-PNO ligands in the equatorial plane and two [TM(CN)6]3- on the apical sites around the rare earth ions in these compounds. A comparison of the magnetic relaxation behaviour in detail reveals that it is more favorable for the Er (4 and 5) than the Dy analogues (2 and 3) to exhibit SIM properties in this axially-elongated D5h coordination environment. Under zero dc field, ac susceptibility measurements show that the Dy analogues have no magnetic relaxation behaviour, while the Er analogues exhibit frequency dependence despite the strong QTM effect. Under a 1 kOe dc field, the Er analogues generally show 1-2 orders of magnitude longer relaxation time at each selected temperature and a higher relaxation energy barrier than the Dy analogues. And the RECo compounds (3 and 5) show a more suppressed QTM effect than the corresponding REFe (2 and 4) compounds, which may be ascribed to the elimination of the fluctuation field from the neighbouring [FeIII]LS ions. The ab initio calculations indicate the misplacement between the orientation of the main magnetic axis and the structural axis in the Dy analogues, and the relative consistency in the Er analogues, which should be the source of the Er analogues showing better SIM properties than the Dy analogues.

8.
Environ Sci Pollut Res Int ; 27(13): 15716-15728, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32086733

RESUMO

Environmental problems caused by mines have been increasing. As one of the most serious types of mining damage caused to the eco-environment, open pits have been the focus of monitoring and management. Previous studies have obtained effective results when evaluating the ecological quality of a mining area by using the remote sensing ecological index (RSEI). However, the calculation of RSEI does not consider that the ecological environmental impact is limited under natural conditions. To overcome this shortcoming, this paper proposes an improved RSEI based on a moving window model, namely the moving window-based remote sensing ecological index (MW-RSEI). This improved index is more in agreement with the First Law of Geography than RSEI. This study uses Landsat ETM/OLI/TIRS images to extract MW-RSEI information of a case area in Zhengzhou City, Henan Province, central China, in 2009 and 2018. The results revealed that the average value of MW-RSEI declined from 0.668 to 0.611 from 2009 to 2018, and the main drivers of the deterioration of the eco-environment were land use/cover (LUCC) changes, most of which were derived from urban expansion and mining. The serious impact of open pits on the eco-environment in mining areas is mainly due to their low vegetation cover; therefore, some effectively managed open pits can have a positive impact on the mining environment. The use of MW-RSEI provides valuable information on the eco-environment surrounding the open pit, which can be used for the rapid and effective monitoring of the eco-environment in mining areas.


Assuntos
Ecossistema , Tecnologia de Sensoriamento Remoto , China , Cidades , Conservação dos Recursos Naturais , Monitoramento Ambiental , Mineração
9.
Zhongguo Zhong Yao Za Zhi ; 43(6): 1289-1291, 2018 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29676142

RESUMO

This paper aimed to analyze the existing acne animal model based on the characteristics of acne clinical symptoms between Chinese and western medicine, in order to provide reference for the establishment of the rational acne animal model. Relevant literatures at home and abroad in recent years were reviewed to summarize the research progress of diagnostic criteria and drug treatment of acne with Chinese and western medicine, and analyze the existing acne animal model. The animal acne models were pathological models, and mainly reflected the clinical indicators of western medicine. Their evaluation was based on western medicine standard, with the standard of Chinese medicine for reference. More improved ideas and methods to establish acne animal models based on clinical study were put forward, so as to establish the reasonable quantitative standard for acne animal model. Furthermore, the animal model based on the combination of disease and syndrome was formed to provide a reliable experimental method for further study of acne. Rational acne animal model shall be selected according to the pathogenesis of acne, in order to improve the consistency between animal model and clinical symptoms, and lay a foundation for further study of acne.


Assuntos
Acne Vulgar , Modelos Animais de Doenças , Medicina Tradicional Chinesa , Animais , Humanos
10.
Shock ; 48(2): 260-269, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28709158

RESUMO

Previous studies have indicated that gut-derived endotoxin played a pivotal role for aggravating systemic inflammatory response to multi-organ dysfunction under heatstroke. Dexmedetomidine (DEX) could protect against inflammation and multi-organ injury in various scenarios. The aim of this study was to explore the protective effect of DEX on heatstroke and the mechanism involved. Male C57BL/6 mice were placed in a controlled climate chamber (40 ±â€Š1°C) until the maximum core temperature (Tc, Max) of 42.7°C, the received criterion of heatstroke, was attained, DEX (25 µg/kg) or 0.9% saline was injected intraperitoneally immediately. The results showed that DEX could significantly attenuate multi-organ injury induced by heatstroke, simultaneously decrease levels of serum inflammatory cytokines through inhibiting the intestinal nuclear factor-κB activation. Furthermore, to assess the effects of DEX on intestine mucosal barrier under heatstroke, the levels of plasma endotoxin, FD4, and D-lactate were detected and the expression of tight junction proteins occludin and ZO-1 was analyzed by western blot and immunohistochemistry. Meanwhile, transmission electron microscopy was employed to confirm the ultrastructure of intestine. Interestingly, we found that DEX decreased the intestinal permeability and sustained the integrity of intestinal barrier. Finally, to evaluate the anti-apoptosis effect of DEX, the pro-apoptotic protein Bax and anti-apoptotic protein Bcl-2 were analyzed by western blot, and terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL) staining was conducted. The results showed that DEX decreased TUNEL-positive cells induced by heatstroke in a Bax/Bcl-2-related manner. Taken together, our results indicate that DEX could protect against inflammation and multi-organ injury induced by heatstroke via sustaining the intestinal integrity.


Assuntos
Dexmedetomidina/farmacologia , Transtornos de Estresse por Calor , Mucosa Intestinal , Intestinos , Insuficiência de Múltiplos Órgãos , Animais , Transtornos de Estresse por Calor/tratamento farmacológico , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/patologia , Mucosa Intestinal/metabolismo , Intestinos/patologia , Masculino , Camundongos , Insuficiência de Múltiplos Órgãos/tratamento farmacológico , Insuficiência de Múltiplos Órgãos/metabolismo , Insuficiência de Múltiplos Órgãos/patologia
11.
Toxicol Appl Pharmacol ; 307: 45-61, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27457977

RESUMO

EPO-018B, a synthetic peptide-based erythropoiesis stimulating agent (ESA), is mainly designed for treatment of anemia caused by chronic renal failure and chemotherapy against cancer. It overcomes the deficiencies of currently approved ESA, including the frequent administration of temperature-sensitive recombinant protein and anti-EPO antibody-mediated pure red cell aplasia (PRCA). This study was designed to evaluate the potential chronic toxicity of EPO-018B. Subcutaneous administration doses were designed as 0, 0.2, 1 and 10mg/kg for six months for 160 rats (20/gender/group) and 0, 0.3, 3 and 20mg/kg for nine months for 32 monkeys (4/gender/group) once every three weeks. The vehicles received the same volume of physiological saline injection. All animals survived to the scheduled necropsies after six weeks (for rats) and fourteen weeks (for monkeys) recovery period, except for the two high-dose female rats and two high-dose male monkeys, which were considered related to the increased RBCs, chronic blood hyperviscosity and chronic cardiac injury. EPO-018B is supposed to be subcutaneously injected once every month and the intended human therapeutic dose is 0.025mg/kg. The study findings at 0.2mg/kg for rats and 0.3mg/kg for monkeys were considered to be the study NOAEL (the no observed adverse effect level), which were more than ten times the intended human therapeutic dose. Higher doses caused adverse effects related to the liver toxicity, cardiotoxicity, appearance of neutralizing antibodies of EPO-018B and the decrease of serum glucose and cholesterol. Most treatment-induced effects were reversible or revealed ongoing recovery upon the discontinuation of treatment. The sequelae occurred in rats and monkeys were considered secondary to exaggerated pharmacology and would less likely occur in the intended patient population. As to the differences between human beings and animals, the safety of EPO-018B need to be further confirmed in the future clinical studies.


Assuntos
Eritropoetina/análogos & derivados , Eritropoetina/toxicidade , Hematínicos/toxicidade , Animais , Anticorpos/sangue , Avaliação Pré-Clínica de Medicamentos , Feminino , Hematínicos/imunologia , Testes Hematológicos , Macaca fascicularis , Masculino , Ratos Sprague-Dawley
12.
Int J Ophthalmol ; 9(6): 898-903, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27366695

RESUMO

AIM: To assess the feasibility of radial optic neurotomy (RON) in central retinal vein occlusion (CRVO) treatment with a Meta-analysis. METHODS: Electronic databases were searched for comprehensive articles that compared efficacy of RON with that of other treatments in CRVO. Study quality was assessed and risk ratio (RR) and 95% confidence interval (CI) with fix- or random-effects model were calculated according to the heterogeneity. RESULTS: A total of 200 eyes from 5 studies were included. The results indicated that no significant differences were found between groups with and without RON in improvement of visual acuity (VA) at 6mo follow-up (pooled RR 0.51, 95%CI 0.22 to 1.18, P=0.117) while improvement of VA showed significantly favourable in patients receiving RON treatment at 12mo follow-up (pooled RR 2.27, 95%CI 1.31 to 3.95, P=0.004). For complications, RON treatment was more effective in reducing neovascular glaucoma (pooled RR 0.45, 95%CI 0.21 to 0.97, P=0.042) but was comparable in retinal detachment (pooled RR 2.41, 95%CI 0.51 to 11.39, P=0.267) and vitreous hemorrhage (pooled RR 0.91, 95%CI 0.33 to 2.46, P=0.847). CONCLUSION: Compared with some certain treatment modalities, RON might offer better VA at 12mo and decrease the rate of neovascular glaucoma without changing the rate of retinal detachment and vitreous hemorrhage. Further studies are required considering the limitation of the research.

13.
Sci Rep ; 5: 13032, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26255557

RESUMO

CFEM domain commonly occurs in fungal extracellular membrane proteins. To provide insights for understanding putative functions of CFEM, we investigate the evolutionary dynamics of CFEM domains by systematic comparative genomic analyses among diverse animals, plants, and more than 100 fungal species, which are representative across the entire group of fungi. We here show that CFEM domain is unique to fungi. Experiments using tissue culture demonstrate that the CFEM-containing ESTs in some plants originate from endophytic fungi. We also find that CFEM domain does not occur in all fungi. Its single origin dates to the most recent common ancestors of Ascomycota and Basidiomycota, instead of multiple origins. Although the length and architecture of CFEM domains are relatively conserved, the domain-number varies significantly among different fungal species. In general, pathogenic fungi have a larger number of domains compared to other species. Domain-expansion across fungal genomes appears to be driven by domain duplication and gene duplication via recombination. These findings generate a clear evolutionary trajectory of CFEM domains and provide novel insights into the functional exchange of CFEM-containing proteins from cell-surface components to mediators in host-pathogen interactions.


Assuntos
Ascomicetos/metabolismo , Basidiomycota/metabolismo , Proteínas Fúngicas/química , Proteínas de Membrana/química , Sequência de Aminoácidos , Animais , Ascomicetos/classificação , Ascomicetos/genética , Basidiomycota/classificação , Basidiomycota/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Sorghum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Zea mays/microbiologia
14.
Regul Toxicol Pharmacol ; 69(3): 558-71, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24928566

RESUMO

CMS-1, mainly composed of imperatorin as its active compound, is a partially purified fraction of a Chinese herbal medicine, Semen Cnidium monnieri. CMS-1 has the potential to be further developed as a new treatment for hypertension. Thus, we studied its toxicity in both Sprague-Dawley rats and beagle dogs. Rats (0-900mg/kg/day) and dogs (0-450mg/kg/day) received CMS-1 orally for 30 consecutive days, followed by a 15-day recovery period. The major target organs of CMS-1 toxicity are the GI (inappetence), liver (hepatocellular necrosis, enzyme elevation), thymus (atrophy), cardiovascular (hypotension), changes in ECG T and P waveforms, elevation of nitrous oxide levels and hematological (RBC parameters disturbances) systems. Most treatment-induced adverse effects were reversible or showed a progressive recovery upon discontinuation of the treatment. The No Observed Adverse Effect Level (NOAEL) was 100mg/kg/day for rats and 50mg/kg/day for dogs. This non-clinical study suggests that clinical monitoring of CMS-1 in patients should focus on the gastrointestinal system, blood tests for liver functions, electrolytes, and blood homeostasis, cardiovascular functions, and immune functions.


Assuntos
Anti-Hipertensivos/efeitos adversos , Cnidium/efeitos adversos , Plantas Medicinais/efeitos adversos , Animais , Cães , Feminino , Testes Hematológicos/métodos , Masculino , Óxido Nitroso/metabolismo , Nível de Efeito Adverso não Observado , Órgãos em Risco , Ratos , Ratos Sprague-Dawley , Segurança
15.
Fa Yi Xue Za Zhi ; 24(2): 85-9, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18605034

RESUMO

OBJECTIVE: To find an objective method for estimation of postmortem interval (PMI) with single-voxel proton MR spectroscopy at different temperature. METHODS: Changes of metabolite peak area and peak area ratio of the N-acetylaspartate (Naa), choline (Cho) and total creatine (Cr) in the brain of 24 rabbit models were measured by 1H-MR spectroscopy (1H-MRS) at 0.5, 1, 2, 4, 6, 8, 12, 16 and 24 h, respectively after death. RESULTS: Naa and Cr decreased continuously with the extension of PMI, and the ratios of Naa/Cr and Cho/Cr also decreased continuously with the extension of PMI within 24 h. The quadratic polynomial regression equation is y=0.0019x2-0.803x+1.4498 (R2=0.962) (Equation 1) with the Naa/Cr used as an independent variable, while the quadratic polynomial regression equation is y=-0.0024x2+0.926x+1.1777 (R2=0.986) (Equation 2) with the Cho/Cr used as an independent variable. The average deviations were about 2.10-37.90 min and 1.69-40.87 min, respectively if the PMI was estimated by Equation 1 and Equation 2, respectively. CONCLUSION: Our study indicates that there is a strong correlation between Naa/Cr, Cho/Cr and PMI, which may be used for estimation of PMI at different temperature.


Assuntos
Química Encefálica , Patologia Legal , Espectroscopia de Ressonância Magnética , Mudanças Depois da Morte , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Colina/análise , Creatina/análise , Coelhos , Temperatura , Fatores de Tempo
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