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2.
BMC Genomics ; 25(1): 373, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627659

RESUMO

The common dolphin (Delphinus delphis) is widely distributed worldwide and well adapted to various habitats. Animal genomes store clues about their pasts, and can reveal the genes underlying their evolutionary success. Here, we report the first high-quality chromosome-level genome of D. delphis. The assembled genome size was 2.56 Gb with a contig N50 of 63.85 Mb. Phylogenetically, D. delphis was close to Tursiops truncatus and T. aduncus. The genome of D. delphis exhibited 428 expanded and 1,885 contracted gene families, and 120 genes were identified as positively selected. The expansion of the HSP70 gene family suggested that D. delphis has a powerful system for buffering stress, which might be associated with its broad adaptability, longevity, and detoxification capacity. The expanded IFN-α and IFN-ω gene families, as well as the positively selected genes encoding tripartite motif-containing protein 25, peptidyl-prolyl cis-trans isomerase NIMA-interacting 1, and p38 MAP kinase, were all involved in pathways for antiviral, anti-inflammatory, and antineoplastic mechanisms. The genome data also revealed dramatic fluctuations in the effective population size during the Pleistocene. Overall, the high-quality genome assembly and annotation represent significant molecular resources for ecological and evolutionary studies of Delphinus and help support their sustainable treatment and conservation.


Assuntos
Golfinhos Comuns , Animais , Evolução Biológica , Cromossomos/genética , Imunidade Inata/genética , Filogenia
3.
Ecotoxicol Environ Saf ; 266: 115558, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37820477

RESUMO

The persistent organic pollutant 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a prevalent congener among polybrominated diphenyl ethers (PBDEs), exhibits potent bioaccumulation and toxicity. Despite extensive research into the adverse effects of BDE-47, its neurotoxicity in sea cucumbers remains unexplored. Given the crucial role of the sea cucumber's nervous system in survival and adaptation, evaluating the impacts of BDE-47 is vital for sustainable aquaculture and consumption. In this study, we employed ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF-MS) to analyze metabolomic changes in neuro-related tissues of Apostichopus japonicus exposed to low (0.1 µg/L), medium (1.0 µg/L), and high (10.0 µg/L) BDE-47 concentrations. We identified significantly changed metabolites in each exposure group (87 in low, 79 in medium, and 102 in high), affecting a variety of physiological processes such as steroid hormone balance, nucleotide metabolism, energy metabolism, neurotransmitter levels, and neuroprotection. In addition, we identified concentration-dependent, common, and some other metabolic responses in the neuro-related tissues. Our findings reveal critical insights into the neurotoxic effects of BDE-47 in sea cucumbers and contribute to risk assessment related to BDE-47 exposure in the sea cucumber industry, paving the way for future neurotoxicological research in invertebrates.


Assuntos
Fenômenos Fisiológicos , Pepinos-do-Mar , Stichopus , Animais , Éteres Difenil Halogenados/toxicidade , Éteres Difenil Halogenados/metabolismo
4.
Angew Chem Int Ed Engl ; 62(13): e202218151, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36727590

RESUMO

Lithium metal batteries hold great promise for promoting energy density and operating at low temperatures, yet they still suffer from insufficient Li compatibility and slow kinetic, especially at ultra-low temperatures. Herein, we rationally design and synthesize a new amphiphilic solvent, 1,1,2,2-tetrafluoro-3-methoxypropane, for use in battery electrolytes. The lithiophilic segment is readily to solvate Li+ to induce self-assembly of the electrolyte solution to form a peculiar core-shell-solvation structure. Such unique solvation structure not only largely improves the ionic conductivity to allow fast Li+ transport and lower the desolvation energy to enable facile desolvation, but also leads to the formation of a highly robust and conductive inorganic SEI. The resulting electrolyte demonstrates high Li efficiency and superior cycling stability from room temperature to -40 °C at high current densities. Meanwhile, anode-free high-voltage cell retains 87 % capacity after 100 cycles.

5.
Mar Pollut Bull ; 185(Pt A): 114198, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274561

RESUMO

The 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) is the predominant congener of polybrominated diphenyl ethers, and it is also a persistent organic pollutant that with a higher detection rate in samples from environment and animals. To date, there have been few studies of the effects of BDE-47 on locomotion in sea cucumbers. In this study, we investigated the influence of different concentrations of BDE-47 (low: 0.1 µg/L; moderate: 1.0 µg/L; high: 10.0 µg/L) on locomotion of Apostichopus japonicus and evaluated changes in their muscle physiology using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The behavioural studies showed that the average and maximum velocity of movement decreased significantly in both the moderate and high BDE-47 groups after 1 day of exposure. In addition, levels of 55 metabolites were identified and characterized in the longitudinal muscle of A. japonicus exposed to BDE-47. The alteration of taurine and norepinephrine levels indicated that BDE-47 had drastic physiological effects on the longitudinal muscle of A. japonicus.


Assuntos
Pepinos-do-Mar , Stichopus , Animais , Éteres Difenil Halogenados/metabolismo , Éter , Músculos/metabolismo
6.
ACS Appl Mater Interfaces ; 14(39): 44470-44478, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36130034

RESUMO

1,2-Dimethoxyethane (DME) has been considered as the most promising electrolyte solvent for Li-metal batteries (LMBs). However, challenges arise from insufficient Li Coulombic efficiency (CE) and poor anodic stability associated with DME-based electrolytes. Here, we proposed a rational molecular design methodology to tailor electrolyte solvation for stable LMBs, where shortening the middle alkyl chain of the solvent could reduce the chelation ability, while increasing the terminal alkyl chain of the solvent could increase the steric hindrance, affording a diethoxymethane (DEM) solvent with ultra-weak solvation ability. When serving as a single solvent for electrolyte, a peculiar solvation structure dominated by contact ion pairs (CIPs) and aggregates (AGGs) was achieved even at a regular salt concentration of 1 m, which gives rise to anion-derived interfacial chemistry. This illustrates an unprecedentedly high Li||Cu CE of 99.1% for a single-salt single-solvent (non-fluorinated) electrolyte at ∼1 m. Moreover, this 1 m DEM-based electrolyte also remarkably suppresses the anodic dissolution of Al current collectors and significantly improves the cycling performance of high-voltage cathodes. This work opens up new frontiers in engineering electrolytes toward stable LMBs with high energy densities.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35648879

RESUMO

This article focuses on the problem of prefixed-time synchronization for stochastic multicoupled delay dynamic networks with reaction-diffusion terms and discontinuous activation by means of local intermittent sampling control. Notably, unlike the existing common fixed-time synchronization, this article puts forward a new synchronization concept, prefixed-time synchronization, based on the fact that stochastic noise and discontinuous activation can be seen everywhere in practical engineering, which can effectively perfect and improve the existing works. Specifically, a local intermittent in the time domain and point sampling control strategy in the spatial domain is proposed instead of a simple single intermittent control approach, which greatly reduces the control cost. In addition, by some effective means, including the famous Young's inequality, Jensen's inequality, and Hölder's inequality, we obtain two different synchronization criteria of the networks without delay and with multicoupling delays and deeply reveal the quantitative relationship among control period, point sampling length, and network scale. Finally, a numerical example is given to verify the effectiveness of the developed method and the practicability by Chua's circuit model.

8.
Nano Lett ; 22(12): 4861-4869, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35675287

RESUMO

The Li dendrite issue is the major barrier that limits the implement of Li metal anode practically, especially at high current density. From the perspective of the nucleation and growth mechanism of the Li dendrite, we rationally develop a novel Prussian blue analogues (PBA)-derived separator, where tuning the metal ions bestows the PBAs with open metal site to confine anion movement and thereby afford a high Li+ transference number (0.78), and PBA with ordered micropores could act as an ionic sieve to selectively extract Li+ and thereby homogenize Li+ flux. This demonstrates a highly reversible Li plating/stripping cycling for 3000 h at a practically high current density (5.0 mA cm-2). Consequently, a high loading Li||LiFeO4 battery (∼10.0 mg cm-2) demonstrates ultralong cycling life at high current densities (∼5.1 mA cm-2). This work highlights the prospect of optimizing PBAs in regulating ion transport behavior to enable high-power Li metal batteries.


Assuntos
Fontes de Energia Elétrica , Lítio , Ferrocianetos , Íons
9.
IEEE Trans Cybern ; 52(11): 11624-11638, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34097632

RESUMO

This article is concerned with the intermittent estimator-based mixed passive and [Formula: see text] control for the high-speed train (HST) with multiple noises, actuator stochastic fault, and sensor packet loss. First, an intermittent estimator is designed to track the undetectable status of HSTs in response to only partial information available due to sensor failures. Then, two different stability criteria are developed by adopting two different Lyapunov function strategies. Simultaneously, in order to reduce the control cost and accelerate the convergence time, two different algorithms are designed. It is worth emphasizing that different from the existing results of HST subject to actuator fault, this article adopts a more flexible fault representation mode, namely, semi-Markov switching mode, which is more in line with the practical background and has a higher valuable application. Especially, the Lyapunov function designed in this article can drive the system state to decrease monotonically in both the "working interval" and the "rest interval," so as to avoid the phenomenon of state impulsive jump. Finally, through the test of HST experimental value of Japan's Shinkansen, the simulation results show the effectiveness and rationality of the proposed control method and also make a comparative analysis with related works, to prove the advantages of the control technology proposed in this article.

10.
J Exp Biol ; 224(19)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34477872

RESUMO

Neuropeptides in the SALMFamide family serve as muscle relaxants in echinoderms and may affect locomotion, as the motor behavior in sea cucumbers involves alternating contraction and extension of the body wall, which is under the control of longitudinal muscle. We evaluated the effect of an L-type SALMFamide neuropeptide (LSA) on locomotory performance of Apostichopus japonicus. We also investigated the metabolites of longitudinal muscle tissue using ultra performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) to assess the potential physiological mechanisms underlying the effect of LSA. The hourly distance, cumulative duration and number of steps moved significantly increased in sea cucumbers in the fourth hour after injection with LSA. Also, the treatment enhanced the mean and maximum velocity by 9.8% and 17.8%, respectively, and increased the average stride by 12.4%. Levels of 27 metabolites in longitudinal muscle changed after LSA administration, and the increased concentration of pantothenic acid, arachidonic acid and lysophosphatidylethanolamine, and the altered phosphatidylethanolamine/phosphatidylcholine ratio are potential physiological mechanisms that could explain the observed effect of LSA on locomotor behavior in A. japonicus.


Assuntos
Neuropeptídeos , Pepinos-do-Mar , Stichopus , Sequência de Aminoácidos , Animais , Locomoção , Músculos
11.
Org Lett ; 23(6): 2074-2077, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33661012

RESUMO

A rhodium-catalyzed hydroformylation of alkynes with formic acid was developed. The method provides α,ß-unsaturated aldehydes in high yield and E-selectivity without the need to handle toxic CO gas.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33486324

RESUMO

Gender differences in physiological characteristics are widespread in animals. Herein, differentially expressed genes (DEGs) in gonads of the sea cucumber Apostichopus japonicus were analysed by transcriptomics, and the results showed that 19,973 genes were commonly expressed in the males and females, 4186 were female-biased, and 2540 were male-biased, 4695 genes were up-regulated in the females and 3436 genes were up-regulated in the males. These DEGs were mainly associated with metabolism, including lipid metabolism, amino acid metabolism, nucleotide metabolism, energy metabolism, and cofactor and vitamin metabolism. 29 Cytochrome P450 (CYP) superfamily genes with gender differential expression were selected, and performed gene identification, phylogenetic, and functional analyses. The results indicated significant roles in multiple metabolic pathways, such as steroid hormone biosynthesis, ovarian steroidogenesis, cortisol synthesis and secretion, arachidonic acid metabolism, linoleic acid metabolism, and retinol metabolism. The findings provide insight into the molecular characteristics of physiological gender differences in sea cucumbers, and will help lay the foundation for the establishment of effective sea cucumber breeding technologies.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Pepinos-do-Mar/genética , Animais , Feminino , Masculino , Caracteres Sexuais , Transcriptoma , Regulação para Cima
13.
Front Physiol ; 11: 559348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192555

RESUMO

Neuropeptides are endogenous active substances that are present in nervous tissues and participate in behavioral and physiological processes of the animal system. Locomotor behavior is basic to predation, escape, reproduction in animals, and neuropeptides play an important role in locomotion. In this study, the function of pedal peptide-type neuropeptide (PDP) in the process of locomotor behavior of the sea cucumber Apostichopus japonicus was evaluated. The locomotor behavior of A. japonicus was recorded by infrared camera before and after PDP administration, and muscle physiology was studied by ultra performance liquid chromatography and quadrupole time-off-light mass spectrometry (UPLC-Q-TOF-MS) to clarify the potential physiological mechanisms. The results showed that PDP enhanced the cumulative duration of moving significantly at the 7th h after injection, and reduced the mean and maximum velocity by 16.90 and 14.22% in A. japonicus. The data of muscle metabolomics suggested that some significantly changed metabolites were related to locomotor behavior of sea cucumbers. The decreases of phosphatidylethanolamine (PE) and phosphatidylcholine (PC) might result in the increases of lysophosphatidylcholines (lysoPC) and lysophosphatidylethanolamine (lysoPE), and suggested the change of fluidity and permeability in the muscle cell membrane, which would affect the physiology and function of muscle cells, and finally alter the locomotor behavior. In addition, the increased level of arachidonic acid (ARA) might activate K+ ion channels and then affect the signaling of muscle cells, or promote the sensitivity of muscle cells to Ca2+ and then result in the contractility of longitudinal muscles in sea cucumbers. ARA was also involved in the linoleic acid metabolism which was the only pathway that disturbed significantly after PDP administration. In conclusion, PDP participated in the regulation of locomotor behavior in the sea cucumber, and the decreased PE and PC, increased lysoPC, lysoPE and ARA might be the potential physiological mechanisms that responsible for behavioral effects of PDP in A. japonicus.

14.
Chem Commun (Camb) ; 56(77): 11433-11436, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32845952

RESUMO

A new non-fullerene acceptor PDFC is prepared by introducing perylene diimide into the core of an A-DA'D-A architecture. Due to the large conjugation and electron-deficient ability of perylene diimide, PDFC shows strong absorption, suitable energy levels and favorable face-on packing. The optimal device realizes a PCE of 12.56% with one of the highest fill factors (81.3%). A PCE of 9.66% is obtained in a 570 nm thick-film device based on PDFC.

15.
Proc Natl Acad Sci U S A ; 116(44): 22347-22352, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31611410

RESUMO

Observing the structure and regeneration of the myelin sheath in peripheral nerves following injury and during repair would help in understanding the pathogenesis and treatment of neurological diseases caused by an abnormal myelin sheath. In the present study, transmission electron microscopy, immunofluorescence staining, and transcriptome analyses were used to investigate the structure and regeneration of the myelin sheath after end-to-end anastomosis, autologous nerve transplantation, and nerve tube transplantation in a rat model of sciatic nerve injury, with normal optic nerve, oculomotor nerve, sciatic nerve, and Schwann cells used as controls. The results suggested that the double-bilayer was the structural unit that constituted the myelin sheath. The major feature during regeneration was the compaction of the myelin sheath, wherein the distance between the 2 layers of cell membrane in the double-bilayer became shorter and the adjacent double-bilayers tightly closed together and formed the major dense line. The expression level of myelin basic protein was positively correlated with the formation of the major dense line, and the compacted myelin sheath could not be formed without the anchoring of the lipophilin particles to the myelin sheath.


Assuntos
Bainha de Mielina/ultraestrutura , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/metabolismo , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Bainha de Mielina/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Ratos
16.
ACS Appl Mater Interfaces ; 11(45): 42438-42446, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31615206

RESUMO

Developing efficient all-polymer solar cells (all-PSCs) has always been a long-standing challenge due to the unfavorable morphology caused by conventional blend casting (BC). Here, we first employ the methodology of sequential processing (SP) with nonorthogonal solvents to fabricate facilely all-PSCs. A highly crystalline polymer donor, PBDB-T, is used to construct a well-organized underlying film, while a new polymer, FPDI-BT1, is selected as the acceptor to be intercalated into the amorphous or semicrystalline regions of PBDB-T during the secondary deposition. By tuning the solvent composition for FPDI-BT1 processing, a bulk heterojunction-like configuration, rather than a traditional bilayer device, is obtained facilely without the need of further processing treatment. The extremely boosted power conversion efficiency of 7.15% from the SP device is achieved, which is more than twice as efficient as the BC analogue (3.57%). The results demonstrate that SP is a promising strategy to fabricate high-performance all-PSCs with tunable configurations of active layers.

17.
Front Physiol ; 10: 221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941049

RESUMO

Melatonin is a highly conserved hormone in evolutionary history. It occurs in numerous organisms and plays a role in the endocrine and immune systems. Locomotor behavior is a basic behavior in animals and is an important indicator of circadian rhythms, which are coordinated by the nervous and endocrine systems. To date, the effect of melatonin on locomotor behavior has been studied in vertebrates, including syrian hamsters, sparrows, rats, zebrafish, goldfish, and flatworms. However, there have been few studies of the effects of melatonin on locomotor behavior in marine invertebrates. The goals of present study were to show the existence of melatonin in the sea cucumber Apostichopus japonicus and to evaluate its effect on locomotor activity. In addition, muscle tissues from control and melatonin-treated sea cucumbers were tested using ultra performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) to determine the changes of metabolic activity in muscle. Melatonin was present in the coelomic fluid of A. japonicus at a concentration of ∼135.0 ng/L. The total distance traveled and number steps taken over 9 h after melatonin administration decreased with increasing concentration of the melatonin dose. Mean and maximum velocity of movement and stride length and stride frequency also decreased, but their differences were not statistically significant. Overall, these results suggest that melatonin administration had a sedative effect on A. japonicus. The levels of 22 different metabolites were altered in the muscle tissues of melatonin-treated sea cucumbers. Serotonin, 9-cis retinoic acid, all-trans retinoic acid, flavin mononucleotide in muscles were downregulated after melatonin administration. Moreover, a high free fatty acid (FFA) concentration and a decrease in the adenosine 5'-triphosphate (ATP) concentration in the muscle tissues of the melatonin-treated group were detected as well. These results suggest that the sedative effect of melatonin involves some other metabolic pathways, and the reduced locomotor modulator-serotonin, inhibited fatty acid oxidation and disturbed oxidative phosphorylation are potential physiological mechanisms that result in the inhibitory effect of melatonin on locomotion in sea cucumbers.

18.
Artigo em Inglês | MEDLINE | ID: mdl-30851504

RESUMO

The sea cucumber Apostichopus japonicus (Selenka) is a valuable economic species in Southeast Asia. It has many fascinating behavioral characteristics, such as autolysis, aestivation, regeneration, and evisceration, thus it is a notable species for studies of special behaviors. Evisceration and autotomy are controlled by the neural network and involve a complicated physiological process. The occurrence of evisceration behavior in sea cucumbers is strongly related to their environment, and it negatively impacts their economic value. Evisceration behavior plays a pivotal role in the survival of A. japonicus, and when it is induced by dramatic changes in the coastal ecological environment and the aquaculture setting it can strongly affect the economic performance of this species. Although numerous studies have focused on intestinal regeneration of A. japonicus, less is known about evisceration behavior, especially its underlying molecular mechanisms. Thus, identification of genes that regulate evisceration in the sea cucumber likely will provide a scientific explanation for this significant specific behavior. In this study, Illumina sequencing (RNA-Seq) was performed on A. japonicus specimens in three states: normal (TCQ), eviscerating (TCZ), and 3 h after evisceration (TCH). In total, 129,905 unigenes were generated with an N50 length of 2651 base pairs, and 54,787 unigenes were annotated from seven functional databases (KEGG, KOG, GO, NR, NT, Interpro, and Swiss-Prot). Additionally, 190, 191, and 320 genes were identified as differentially expressed genes (DEGs) in the comparisons of TCQ vs. TCZ, TCZ vs. TCH, and TCQ vs. TCH, respectively. These DEGs mapped to 157, 113, and 190 signaling pathways in the KEGG database, respectively. KEGG analyses also revealed that potential DEGs enriched in the categories of "environmental information processing," "organismal system," "metabolism," and "cellular processes," and they were involved in evisceration behavior in A. japonicus. These DEGs are related to muscle contraction, hormone and neurotransmitter secretion, nerve and muscle damage, energy support, cellular stress, and apoptosis. In conclusion, through our comparative analysis of A. japonicus in different stages, we identified many candidate evisceration-related genes and signaling pathways that likely are involved in evisceration behavior. These results should help further elucidate the mechanisms underlying evisceration behavior in sea cucumbers.


Assuntos
Estivação , Stichopus/genética , Transcriptoma , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Stichopus/fisiologia
19.
Kidney Int Rep ; 3(4): 970-978, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29988980

RESUMO

INTRODUCTION: Local inflammation is an important regulator of vascular remodeling. We hypothesized that adipose tissue adjacent to hemodialysis arteriovenous fistulae modulates maturation. METHODS: During fistula creation, perivenous adipose was collected from 111 participants in the Hemodialysis Fistula Maturation Study. Nine adipose-associated mediators were measured. Duplex ultrasound was performed at 4 time points postoperatively from 1 day to first cannulation (10-26 weeks). Associations between logarithmically transformed biomarker levels and fistula remodeling were evaluated using mixed effects regression. RESULTS: Elevated interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1 were associated with a reduction in the fractional vein diameter during the early time frame of 1 day to 2 weeks (diameter change of 26.6% and 20.4% at the 25th and 75th percentile for IL-6, P = 0.01; 27.8% and 21.1% at the 25th and 75th percentile for MCP-1, P = 0.02), but not in later stages of remodeling. Local leptin levels showed a significant negative correlation with fractional venous flow increase between 2 and 6 weeks (percent flow change 31.4% and 11.3% at the 25th and 75th percentile for leptin, P = 0.03). CONCLUSION: Thus, impaired fistula vein dilation and reduced capacity for flow augmentation associate with specific local adipose phenotypic signatures in a time-dependent manner. In view of adipose tissue plasticity, these findings raise the possibility of novel adipose-based strategies to facilitate fistula maturation.

20.
Acta Radiol ; 59(9): 1074-1081, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29378421

RESUMO

Background Non-invasive monitoring of autologous vein graft (VG) bypass grafts is largely limited to detecting late luminal narrowing. Although magnetic resonance imaging (MRI) delineates vein graft intima, media, and adventitia, which may detect early failure, the scan time required to achieve sufficient resolution is at present impractical. Purpose To study VG visualization enhancement in vivo and delineate whether a covalently attached MRI contrast agent would enable quicker longitudinal imaging of the VG wall. Material and Methods Sixteen 12-week-old male C57BL/6J mice underwent carotid interposition vein grafting. The inferior vena cava of nine donor mice was treated with a gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA)-based contrast agent, with control VGs labeled with a vehicle. T1-weighted (T1W) MRI was performed serially at postoperative weeks 1, 4, 12, and 20. A portion of animals was sacrificed for histopathology following each imaging time point. Results MRI signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were significantly higher for treated VGs in the first three time points (1.73 × higher SNR, P = 0.0006, and 5.83 × higher CNR at the first time point, P = 0.0006). However, MRI signal enhancement decreased consistently in the study period, to 1.29 × higher SNR and 2.64 × higher CNR, by the final time point. There were no apparent differences in graft morphometric analyses in Masson's trichrome-stained sections. Conclusion A MRI contrast agent that binds covalently to the VG wall provides significant increase in T1W MRI signal with no observed adverse effects in a mouse model. Further optimization of the contrast agent to enhance its durability is required.


Assuntos
Implante de Prótese Vascular/métodos , Artérias Carótidas/cirurgia , Meios de Contraste/farmacologia , Gadolínio DTPA/farmacologia , Veia Cava Inferior/transplante , Animais , Modelos Animais de Doenças , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Razão Sinal-Ruído
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