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PURPOSE: To improve liver proton density fat fraction (PDFF) and R 2 * $$ {R}_2^{\ast } $$ quantification at 0.55 T by systematically validating the acquisition parameter choices and investigating the performance of locally low-rank denoising methods. METHODS: A Monte Carlo simulation was conducted to design a protocol for PDFF and R 2 * $$ {R}_2^{\ast } $$ mapping at 0.55 T. Using this proposed protocol, we investigated the performance of robust locally low-rank (RLLR) and random matrix theory (RMT) denoising. In a reference phantom, we assessed quantification accuracy (concordance correlation coefficient [ ρ c $$ {\rho}_c $$ ] vs. reference values) and precision (using SD) across scan repetitions. We performed in vivo liver scans (11 subjects) and used regions of interest to compare means and SDs of PDFF and R 2 * $$ {R}_2^{\ast } $$ measurements. Kruskal-Wallis and Wilcoxon signed-rank tests were performed (p < 0.05 considered significant). RESULTS: In the phantom, RLLR and RMT denoising improved accuracy in PDFF and R 2 * $$ {R}_2^{\ast } $$ with ρ c $$ {\rho}_c $$ >0.992 and improved precision with >67% decrease in SD across 50 scan repetitions versus conventional reconstruction (i.e., no denoising). For in vivo liver scans, the mean PDFF and mean R 2 * $$ {R}_2^{\ast } $$ were not significantly different between the three methods (conventional reconstruction; RLLR and RMT denoising). Without denoising, the SDs of PDFF and R 2 * $$ {R}_2^{\ast } $$ were 8.80% and 14.17 s-1. RLLR denoising significantly reduced the values to 1.79% and 5.31 s-1 (p < 0.001); RMT denoising significantly reduced the values to 2.00% and 4.81 s-1 (p < 0.001). CONCLUSION: We validated an acquisition protocol for improved PDFF and R 2 * $$ {R}_2^{\ast } $$ quantification at 0.55 T. Both RLLR and RMT denoising improved the accuracy and precision of PDFF and R 2 * $$ {R}_2^{\ast } $$ measurements.
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PURPOSE: Balanced steady-state free precession (bSSFP) imaging is susceptible to outflow effects where excited spins leaving the slice as part of the blood stream are misprojected back onto the imaging plane. Previous work proposed using slice-encoding steps to localize these outflow effects from corrupting the target slice, at the expense of prolonged scan time. This present study extends this idea by proposing a means of significantly reducing most of the outflowing signal from the imaged slice using a coil localization method that acquires a slice-encoded calibration scan in addition to the 2D data, without being nearly as time-demanding as our previous method. This coil localization method is titled UNfolding Coil Localized Errors from an imperfect slice profile using a Structured Autocalibration Matrix (UNCLE SAM). METHODS: Retrospective and prospective evaluations were carried out. Both featured a 2D acquisition and a separate slice-encoded calibration of the center in-plane k $$ k $$ -space lines across all desired slice-encoding steps. RESULTS: Retrospective results featured a slice-by-slice comparison of the slice-encoded images with UNCLE SAM. UNCLE SAM's subtraction from the slice-encoded image was compared with a subtraction from the flow-corrupted 2D image, to demonstrate UNCLE SAM's capability to unfold outflowing spins. UNCLE SAM's comparison with slice encoding showed that UNCLE SAM was able to unfold up to 74% of what slice encoding achieved. Prospective results showed significant reduction in outflow effects with only a marginal increase in scan time from the 2D acquisition. CONCLUSIONS: We developed a method that effectively unfolds most outflowing spins from corrupting the target slice and does not require the explicit use of slice-encoding gradients. This development offers a method to reduce most outflow effects from the target slice within a clinically feasible scan duration compared with the fully sampled slice-encoding technique.
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OBJECTIVE: To develop and evaluate a technique combining eddy current-nulled convex optimized diffusion encoding (ENCODE) with random matrix theory (RMT)-based denoising to accelerate and improve the apparent signal-to-noise ratio (aSNR) and apparent diffusion coefficient (ADC) mapping in high-resolution prostate diffusion-weighted MRI (DWI). MATERIALS AND METHODS: Eleven subjects with clinical suspicion of prostate cancer were scanned at 3T with high-resolution (HR) (in-plane: 1.0 × 1.0 mm2) ENCODE and standard-resolution (1.6 × 2.2 mm2) bipolar DWI sequences (both had 7 repetitions for averaging, acquisition time [TA] of 5 min 50 s). HR-ENCODE was retrospectively analyzed using three repetitions (accelerated effective TA of 2 min 30 s). The RMT-based denoising pipeline utilized complex DWI signals and Marchenko-Pastur distribution-based principal component analysis to remove additive Gaussian noise in images from multiple coils, b-values, diffusion encoding directions, and repetitions. HR-ENCODE with RMT-based denoising (HR-ENCODE-RMT) was compared with HR-ENCODE in terms of aSNR in prostate peripheral zone (PZ) and transition zone (TZ). Precision and accuracy of ADC were evaluated by the coefficient of variation (CoV) between repeated measurements and mean difference (MD) compared to the bipolar ADC reference, respectively. Differences were compared using two-sided Wilcoxon signed-rank tests (P < 0.05 considered significant). RESULTS: HR-ENCODE-RMT yielded 62% and 56% higher median aSNR than HR-ENCODE (b = 800 s/mm2) in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT achieved 63% and 70% lower ADC-CoV than HR-ENCODE in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT ADC and bipolar ADC had low MD of 22.7 × 10-6 mm2/s in PZ and low MD of 90.5 × 10-6 mm2/s in TZ. CONCLUSIONS: HR-ENCODE-RMT can shorten the acquisition time and improve the aSNR of high-resolution prostate DWI and achieve accurate and precise ADC measurements in the prostate.
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Algoritmos , Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Próstata , Neoplasias da Próstata , Razão Sinal-Ruído , Humanos , Masculino , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Próstata/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos , Análise de Componente Principal , Aumento da Imagem/métodos , Artefatos , Reprodutibilidade dos TestesRESUMO
Antimicrobial resistance poses an escalating threat to human health, necessitating the development of novel antimicrobial agents capable of addressing challenges posed by antibiotic-resistant bacteria. Thanatin, a 21-amino acid ß-hairpin insect antimicrobial peptide featuring a single disulfide bond, exhibits broad-spectrum antibacterial activity, particularly effective against multidrug-resistant strains. The outer membrane biosynthesis system is recognized as a critical vulnerability in antibiotic-resistant bacteria, which thanatin targets to exert its antimicrobial effects. This peptide holds significant promise for diverse applications. This review begins with an examination of the structure-activity relationship and synthesis methods of thanatin. Subsequently, it explores thanatin's antimicrobial activity, detailing its various mechanisms of action. Finally, it discusses prospective clinical, environmental, food, and agricultural applications of thanatin, offering valuable insights for future research endeavors.
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Peptídeos Catiônicos Antimicrobianos , Farmacorresistência Bacteriana Múltipla , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Antibacterianos/farmacologia , Antibacterianos/química , Relação Estrutura-Atividade , Animais , Bactérias/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Testes de Sensibilidade MicrobianaRESUMO
The close-coupled selective catalytic reduction (cc-SCR) catalyst is an effective technology to reduce tailpipe NOx emission during cold start. This paper investigated the optimal ammonia storage under steady and transient state in the cc-SCR. The study showed that a trade-off between NOx conversion efficiency and ammonia slip is observed on the pareto solutions under steady state, and the optimal ammonia storage is calculated with ammonia slip less than 10 µL/L based on the China â ¥ emission legislation. The rapid temperature increase will lead to severe ammonia slip in the transient test cycle. A simplified 0-D calculation method on ammonia slip under transient state is proposed based on kinetic model of ammonia adsorption and desorption. In addition, the effect of ammonia storage, catalyst temperature and temperature increasing rate on ammonia slip are analyzed. The optimal ammonia storage is calculated with maximum ammonia slip less than 100 µL/L according to the oxidation efficiency of ammonia slip catalyst (ASC) downstream cc-SCR. It was found that the optimal ammonia storage under transient state is much lower than that under steady state in cc-SCR at lower temperature, and a phase diagram is established to analyze the influence of temperature and temperature increasing rate on optimal ammonia storage.
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Amônia , Temperatura Baixa , Oxirredução , Temperatura , CatáliseRESUMO
The safety and integrity of the global food system is in a constant state of flux with persistent chemical and microbial risks. While chemical risks are being managed systematically, microbial risks pose extra challenges. Antimicrobial resistant microorganism and persistence of related antibiotic resistance genes (ARGs) in the food chain adds an extra dimension to the management of microbial risks. Because the food chain microbiome is a key interface in the global health system, these microbes can affect health in many ways. In this review, we systematically summarize the distribution of ARGs in foods, describe the potential transmission pathway and transfer mechanism of ARGs from farm to fork, and discuss potential food safety problems and challenges. Modulating antimicrobial resistomes in the food chain facilitates a sustainable global food production system.
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Nitrated α-syn (nitro-α-syn) is a biomarker for Parkinson's desease (PD), and its sensitive detection in serum is of great importance for early PD diagnosis. Silver-coated copper MOF (Cu-MOF@Ag) with outstanding oxidase activity and electrochemical response property was designed and synthesized. Cu-MOF@Ag exhibited excellent oxidase activity with a low Km value (0.568 mM), avoiding the addition of strong oxidant to catalyze chromogenic substrate, which enhanced the colorimetric stability. Silver nanoparticles as an electrochemical signal reporter can be easily decorated on the surface of Cu-MOF with bifunctional groups (-SH and -NH2) material, which can increase the electrochemical signal output. The α-syn antibody modified Cu-MOF@Ag and nitro-α-syn modified magnetic nanoparticle were used as immunoprobes to specifically capture nitro-α-syn. A dual-modal immunosensor was fabricated for the simple and reliable detection of nitro-α-syn based on Cu-MOF@Ag. Combing colorimetric and electrochemical detection, nitro-α-syn can be determined quantitatively within a wide linear range (10-350 ng/mL) with low detection limit (0.5 ng/mL). The ability of the sensor with magnetic separation and dual signal analysis allowed to successfully detect nitro-α-syn and distinguish PD patients from healthy people (P < 0.005). Thanks to its excellent selectivity, stability, and the precision of 2.69%, the dual-modal sensor has potential clinical application for nitro-α-syn detection and paves a new way for PD diagnosis at its early stage.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , Humanos , alfa-Sinucleína , Nitratos , Prata/química , Estruturas Metalorgânicas/química , Nanopartículas Metálicas/química , Imunoensaio , OxirredutasesRESUMO
The rapid and sensitive detection of pathogenic bacteria is highly demanded for early warning of infectious disease epidemics and protection of human health. Herein, a reusable and universal impedimetric sensing platform based on a bacteria-imprinted polythiophene film (BIF) is proposed for the rapid and sensitive detection of pathogenic bacteria using Staphylococcus aureus (S. aureus) as a model analyte. Monomer screening among four 3-substituted thiophenes was first performed based on the imprinting factor, and 3-thiopheneethanol (TE) was eventually selected. The BIF as a recognition layer was quickly deposited in an environmentally friendly process on a glassy carbon electrode via electro-copolymerization of the S. aureus template and TE monomer followed by in situ template removal. Upon rebinding of S. aureus on the BIF, the impedance increased. Under optimal conditions, the BIF-based sensor can quantitatively detect S. aureus in a wide linear range of 10 to 107 CFU mL-1 with a low detection limit of 4 CFU mL-1. Additionally, the sensor exhibits excellent selectivity, capable of identifying S. aureus from multi-bacterial strain mixtures. It also demonstrates applicability in the analysis of real lettuce and shrimp samples with good recoveries. Most significantly, the BIF sensing interface can be reused up to five times with good signal retention. Compared with most reported methods, this sensor is more rapid with a much shorter total assay time of 30 min, including the BIF preparation, bacterial rebinding, and impedance detection. This assay may hold great potential to help in the rapid, sensitive, and label-free detection of pathogenic bacteria in fields of food safety and public health.
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Técnicas Biossensoriais , Infecções Estafilocócicas , Técnicas Biossensoriais/métodos , Carbono , Humanos , Limite de Detecção , Polímeros , Staphylococcus aureus , TiofenosRESUMO
The localization of lipoprotein (Lol) system is responsible for the transport of lipoproteins in the outer membrane (OM) of Vibrio parahaemolyticus. LolB catalyzes the last step in the Lol system, where lipoproteins are inserted into the OM. If the function of LolB is impeded, growth of V. parahaemolyticus is inhibited, due to lack of an intact OM barrier for protection against the external environment. Additionally, it becomes progressively harder to generate antimicrobial resistance (AMR). In this study, LolB was employed as the receptor for a high-throughput virtual screening from a natural compounds database. Compounds with higher glide score were selected for an inhibition assay against V. parahaemolyticus. It was found that procyanidin, stevioside, troxerutin and rutin had both exciting binding affinity with LolB in the micromolar range and preferable antibacterial activity in a concentration-dependent manner. The inhibition rates of 100 ppm were 87.89%, 86.2%, 91.39% and 83.71%, respectively. The bacteriostatic mechanisms of the four active compounds were explored further via fluorescence spectroscopy and molecular docking, illustrating that each molecule formed a stable complex with LolB via hydrogen bonds and pi-pi stacking interactions. Additionally, the critical sites for interaction with V. parahaemolyticus LolB, Tyr108 and Gln68, were also illustrated. This paper demonstrates the inhibition of LolB, thus, leading to antibacterial activity, and identifies LolB as a promising drug target for the first time. These compounds could be the basis for potential antibacterial agents against V. parahaemolyticus.
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Proteínas de Escherichia coli , Proteínas Periplásmicas de Ligação , Vibrio parahaemolyticus , Proteínas de Escherichia coli/metabolismo , Proteínas Periplásmicas de Ligação/metabolismo , Proteínas da Membrana Bacteriana Externa/química , Vibrio parahaemolyticus/metabolismo , Escherichia coli/metabolismo , Simulação de Acoplamento Molecular , Chaperonas Moleculares/metabolismo , Lipoproteínas/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismoRESUMO
How to use bioinformatics methods to quickly and accurately locate the effective targets of traditional Chinese medicine monomer (TCM) is still an urgent problem needing to be solved. Here, we used high-throughput sequencing to identify the genes that were up-regulated after cells were treated with TCM monomers and used bioinformatics methods to analyze which transcription factors activated these genes. Then, the binding proteins of these transcription factors were analyzed and cross-analyzed with the docking proteins predicted by small molecule reverse docking software to quickly and accurately determine the monomer's targets. Followeding this method, we predicted that the TCM monomer Daphnoretin (DT) directly binds to JAK2 with a binding energy of -5.43 kcal/mol, and activates the JAK2/STAT3 signaling transduction pathway. Subsequent Western blotting and in vitro binding and kinase experiments further validated our bioinformatics predictions. Our method provides a new approach for quickly and accurately locating the effective targets of TCM monomers, and we also have discovered for the first time that TCM monomer DT is an agonist of JAK2.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Biologia Computacional , Medicamentos de Ervas Chinesas/farmacologia , Simulação de Acoplamento Molecular , Transdução de Sinais , Fatores de TranscriçãoRESUMO
Worldwide, foods waste caused by putrefactive organisms and diseases caused by foodborne pathogens persist as public health problems even with a plethora of modern antimicrobials. Our over reliance on antimicrobials use in agriculture, medicine, and other fields will lead to a postantibiotic era where bacterial genotypic resistance, phenotypic adaptation, and other bacterial evolutionary strategies cause antimicrobial resistance (AMR). This AMR is evidenced by the emergence of multiple drug-resistant (MDR) bacteria and pan-resistant (PDR) bacteria, which produces cross-contamination in multiple fields and poses a more serious threat to food safety. A "red queen premise" surmises that the coevolution of phages and bacteria results in an evolutionary arms race that compels phages to adapt and survive bacterial antiphage strategies. Phages and their lysins are therefore useful toolkits in the design of novel antimicrobials in food protection and foodborne pathogens control, and the modality of using phages as a targeted vector against foodborne pathogens is gaining momentum based on many encouraging research outcomes. In this review, we discuss the rationale of using phages and their lysins as weapons against spoilage organisms and foodborne pathogens, and outline the targeted conquest or dodge mechanism of phages and the development of novel phage prospects. We also highlight the implementation of phages and their lysins to control foodborne pathogens in a farm-table-hospital domain in the postantibiotic era.
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Infecções Bacterianas , Bacteriófagos , Bactérias/genética , Inocuidade dos Alimentos , HumanosRESUMO
Background Microstructural MRI has the potential to improve diagnosis and characterization of prostate cancer (PCa), but validation with histopathology is lacking. Purpose To validate ex vivo diffusion-relaxation correlation spectrum imaging (DR-CSI) in the characterization of microstructural tissue compartments in prostate specimens from men with PCa by using registered whole-mount digital histopathology (WMHP) as the reference standard. Materials and Methods Men with PCa who underwent 3-T MRI and robotic-assisted radical prostatectomy between June 2018 and January 2019 were prospectively studied. After prostatectomy, the fresh whole prostate specimens were imaged in patient-specific three-dimensionally printed molds by using 3-T MRI with DR-CSI and were then sliced to create coregistered WMHP slides. The DR-CSI spectral signal component fractions (fA, fB, fC) were compared with epithelial, stromal, and luminal area fractions (fepithelium, fstroma, flumen) quantified in PCa and benign tissue regions. A linear mixed-effects model assessed the correlations between (fA, fB, fC) and (fepithelium, fstroma, flumen), and the strength of correlations was evaluated by using Spearman correlation coefficients. Differences between PCa and benign tissues in terms of DR-CSI signal components and microscopic tissue compartments were assessed using two-sided t tests. Results Prostate specimens from nine men (mean age, 65 years ± 7 [standard deviation]) were evaluated; 20 regions from 17 PCas, along with 20 benign tissue regions of interest, were analyzed. Three DR-CSI spectral signal components (spectral peaks) were consistently identified. The fA, fB, and fC were correlated with fepithelium, fstroma, and flumen (all P < .001), with Spearman correlation coefficients of 0.74 (95% confidence interval [CI]: 0.62, 0.83), 0.80 (95% CI: 0.66, 0.89), and 0.67 (95% CI: 0.51, 0.81), respectively. PCa exhibited differences compared with benign tissues in terms of increased fA (PCa vs benign, 0.37 ± 0.05 vs 0.27 ± 0.06; P < .001), decreased fC (PCa vs benign, 0.18 ± 0.06 vs 0.31 ± 0.13; P = .01), increased fepithelium (PCa vs benign, 0.44 ± 0.13 vs 0.26 ± 0.16; P < .001), and decreased flumen (PCa vs benign, 0.14 ± 0.08 vs 0.27 ± 0.18; P = .004). Conclusion Diffusion-relaxation correlation spectrum imaging signal components correlate with microscopic tissue compartments in the prostate and differ between cancer and benign tissue. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Lee and Hectors in this issue.
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Imagem de Difusão por Ressonância Magnética/métodos , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Histocitoquímica , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Prostate diffusion-weighted imaging (DWI) using monopolar encoding is sensitive to eddy-current-induced distortion artifacts. Twice-refocused bipolar encoding suppresses eddy current artifacts, but increases echo time (TE), leading to lower signal-to-noise ratio (SNR). Optimization of the diffusion encoding might improve prostate DWI. PURPOSE: To evaluate eddy current nulled convex optimized diffusion encoding (ENCODE) for prostate DWI with minimal TE. STUDY TYPE: Prospective cohort study. POPULATION: A diffusion phantom, an ex vivo prostate specimen, 10 healthy male subjects (27 ± 3 years old), and five prostate cancer patients (62 ± 7 years old). FIELD STRENGTH/SEQUENCE: 3T; single-shot spin-echo echoplanar DWI. ASSESSMENT: Eddy-current artifacts, TE, SNR, apparent diffusion coefficient (ADC), and image quality scores from three independent readers were compared between monopolar, bipolar, and ENCODE prostate DWI for standard-resolution (1.6 × 1.6 mm2 , partial Fourier factor [pF] = 6/8) and higher-resolution protocols (1.6 × 1.6 mm2 , pF = off; 1.0 × 1.0 mm2 , pF = 6/8). STATISTICAL TESTING: SNR and ADC differences between techniques were tested with Kruskal-Wallis and Wilcoxon signed-rank tests (P < 0.05 considered significant). RESULTS: Eddy current suppression with ENCODE was comparable to bipolar encoding (mean coefficient of variation across three diffusion directions of 9.4% and 9%). For a standard-resolution protocol, ENCODE achieved similar TE as monopolar and reduced TE by 14 msec compared to bipolar, resulting in 27% and 29% higher mean SNR in prostate transition zone (TZ) and peripheral zone (PZ) (P < 0.05) compared to bipolar, respectively. For higher-resolution protocols, ENCODE achieved the shortest TE (67 msec), with 17-21% and 58-70% higher mean SNR compared to monopolar (TE = 77 msec) and bipolar (TE = 102 msec) in PZ and TZ (P < 0.05). No significant differences were found in mean TZ (P = 0.91) and PZ ADC (P = 0.94) between the three techniques. ENCODE achieved similar or higher image quality scores than bipolar DWI in patients, with mean intraclass correlation coefficient of 0.77 for overall quality between three independent readers. DATA CONCLUSION: ENCODE minimizes TE (improves SNR) and reduces eddy-current distortion for prostate DWI compared to monopolar and bipolar encoding. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:1526-1539.
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Imagem de Difusão por Ressonância Magnética , Próstata , Adulto , Idoso , Imagem Ecoplanar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Reprodutibilidade dos Testes , Adulto JovemRESUMO
BACKGROUND: Patient-specific 3D-printed molds and ex vivo MRI of the resected prostate have been two important strategies to align MRI with whole-mount histopathology (WMHP) for prostate cancer (PCa) research, but the combination of these two strategies has not been systematically evaluated. PURPOSE: To develop and evaluate a system that combines patient-specific 3D-printed molds with ex vivo MRI (ExV) to spatially align in vivo MRI (InV), ExV, and WMHP in PCa patients. STUDY TYPE: Prospective cohort study. POPULATION: Seventeen PCa patients who underwent 3T MRI and robotic-assisted laparoscopic radical prostatectomy (RALP). FIELD STRENGTH/SEQUENCES: T2 -weighted turbo spin-echo sequences at 3T. ASSESSMENT: Immediately after RALP, the fresh whole prostate specimens were imaged in patient-specific 3D-printed molds by 3T MRI and then sectioned to create WMHP slides. The time required for ExV was measured to assess impact on workflow. InV, ExV, and WMHP images were registered. Spatial alignment was evaluated using: slide offset (mm) between ExV slice locations and WMHP slides; overlap of the 3D prostate contour on InV versus ExV using Dice's coefficient (0 to 1); and 2D target registration error (TRE, mm) between corresponding landmarks on InV, ExV, and WMHP. Data are reported as mean ± standard deviation (SD). STATISTICAL TESTING: Differences in 2D TRE before versus after registration were compared using the Wilcoxon signed-rank test (P < 0.05 considered significant). RESULTS: ExV (duration 115 ± 15 min) was successfully incorporated into the workflow for all cases. Absolute slide offset was 1.58 ± 1.57 mm. Dice's coefficient was 0.865 ± 0.035. 2D TRE was significantly reduced after registration (P < 0.01) with mean (±SD of per patient means) of 1.9 ± 0.6 mm for InV versus ExV, 1.4 ± 0.5 mm for WMHP versus ExV, and 2.0 ± 0.5 mm for WMHP versus InV. DATA CONCLUSION: The proposed system combines patient-specific 3D-printed molds with ExV to achieve spatial alignment between InV, ExV, and WMHP with mean 2D TRE of 1-2 mm. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;49:270-279.
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Imageamento por Ressonância Magnética , Impressão Tridimensional , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Desenho de Equipamento , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prostatectomia/métodos , Reprodutibilidade dos Testes , Procedimentos Cirúrgicos Robóticos , Robótica , Glândulas Seminais/patologiaRESUMO
The effects of cellular prion protein on rapid eye movement sleep deprivation-induced spatial memory impairment were investigated, and the related mechanisms explored. Male C57BL/6 mice were randomly divided into four groups: environment control, sleep deprivation control, sleep-deprived-plasmid adeno-associated virus-green fluorescent protein group, and sleep-deprived-plasmid adeno-associated virus-cellular prion protein-green fluorescent protein group. Overexpression of cellular prion protein was induced by stereotaxic injection of adeno-associated viral plasmids-CAG-enhanced green fluorescent protein-cellular prion protein-Flag (a small label, which can be detected with corresponding tagged antibodies) into the hippocampus. Sleep-deprived mice were allowed no rapid eye movement sleep for 72 hours. Morris water maze was used to assess the effects of cellular prion protein on spatial learning and memory. The expression of amyloid-ß was also investigated in all groups. The sleep-deprived- plasmid adeno-associated virus- cellular prion protein-green fluorescent protein group spent significantly more time in a goal quadrant compared with the sleep-deprived- plasmid adeno-associated virus-green fluorescent protein group. Sleep deprivation resulted in increased amyloid-ß in the hippocampus, which was reversed by the overexpression of hippocampus cellular prion protein. Overexpression of cellular prion protein in the hippocampus rescues rapid eye movement sleep deprivation-induced spatial memory impairment in mice. It is shown that amyloid-ß in the hippocampus might be one of the mechanisms.
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Peptídeos beta-Amiloides/metabolismo , Comportamento Animal/fisiologia , Hipocampo/metabolismo , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Proteínas Priônicas/metabolismo , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Memória Espacial/fisiologia , Animais , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Priônicas/efeitos dos fármacos , Distribuição Aleatória , Sono REMRESUMO
Both the central and peripheral vestibular systems contribute to the pathogenesis of vestibular migraine, although the mechanism of vestibular migraine remains unclear. To assess central and peripheral vestibular system damage in vestibular migraine and explore the underlying mechanism we performed vestibular function tests, including a caloric test, spontaneous, gaze-evoked nystagmus and saccadic, pursuit and optokinetic eye movements to evaluate the involvement of the central and/or peripheral vestibular system in subjects with acute vestibular migraine episodes. It was found that both peripheral and central vestibular systems were damaged in vestibular migraine patients with the number of subjects with central deficits significantly larger than those with peripheral deficits. The cerebellum, especially the vestibule cerebellum, is the most important part of the central vestibular system. Locculus and paraflocculus are essential structures of cerebellar circuitry controlling vestibular nuclei and oculomotor functions and are anatomically linked with the "migraine pathway". Purkinje cells are the only source of cerebellar output and it innervates inhibitory action. Therefore, we examined the effect of the electric stimulation on paraflocculus Purkinje cells by using a specific electrical stimulation of trigeminal ganglia to induce a migraine-like phenomenon in animal part. Moreover, electrophysiological recordings showed that parafloccular Purkinje cells of rats underwent electrical stimulation of trigeminal ganglia resulted in partial inhibition. It is suggested that Purkinje cells in the paraflocculus could be inhibited after the occurrence of migraine episode and this inhibition may be an important factor leading to vestibular migraine.
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Cerebelo/fisiopatologia , Transtornos de Enxaqueca/etiologia , Transtornos de Enxaqueca/fisiopatologia , Inibição Neural/fisiologia , Células de Purkinje/fisiologia , Gânglio Trigeminal/fisiopatologia , Vertigem/fisiopatologia , Vestíbulo do Labirinto/fisiopatologia , Doença Aguda , Adulto , Animais , Modelos Animais de Doenças , Estimulação Elétrica , Feminino , Humanos , Masculino , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-DawleyRESUMO
PURPOSE: To evaluate a technique for simultaneous quantitative T2 and apparent diffusion coefficient (ADC) mapping in the heart (T2 +ADC) using spin echo (SE) diffusion-weighted imaging (DWI). THEORY AND METHODS: T2 maps from T2 +ADC were compared with single-echo SE in phantoms and with T2 -prepared (T2 -prep) balanced steady-state free precession (bSSFP) in healthy volunteers. ADC maps from T2 +ADC were compared with conventional DWI in phantoms and in vivo. T2 +ADC was also demonstrated in a patient with acute myocardial infarction (MI). RESULTS: Phantom T2 values from T2 +ADC were closer to a single-echo SE reference than T2 -prep bSSFP (-2.3 ± 6.0% vs 22.2 ± 16.3%; P < 0.01), and ADC values were in excellent agreement with DWI (0.28 ± 0.4%). In volunteers, myocardial T2 values from T2 +ADC were significantly shorter than T2 -prep bSSFP (35.8 ± 3.1 vs 46.8 ± 3.8 ms; P < 0.01); myocardial ADC was not significantly (N.S.) different between T2 +ADC and conventional motion-compensated DWI (1.39 ± 0.18 vs 1.38 ± 0.18 mm2 /ms; P = N.S.). In the patient, T2 and ADC were both significantly elevated in the infarct compared with remote myocardium (T2 : 40.4 ± 7.6 vs 56.8 ± 22.0; P < 0.01; ADC: 1.47 ± 0.59 vs 1.65 ± 0.65 mm2 /ms; P < 0.01). CONCLUSION: T2 +ADC generated coregistered, free-breathing T2 and ADC maps in healthy volunteers and a patient with acute MI with no cost in accuracy, precision, or scan time compared with DWI. Magn Reson Med 79:654-662, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Técnicas de Imagem Cardíaca/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Algoritmos , Coração/diagnóstico por imagem , Humanos , Movimento/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Imagens de Fantasmas , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Vibrio parahaemolyticus and Listeria monocytogenes are seafood pathogens of public health significance, and predictive models are effective tools for quantitative microbial risk assessment of these pathogens. However, most current predictive models are based on growth of single strains in broth cultures, and interactions of two or more bacteria in a food matrix can skew the outcomes of the predictions. Therefore, the impact of V. parahaemolyticus and L. monocytogenes when co-cultured and in monoculture on cooked shrimp in cold storage was investigated. RESULTS: The results indicated that L. monocytogenes co-cultured with V. parahaemolyticus exhibited reduced growth and longer lag phase at 4 °C and 10 °C. V. parahaemolyticus exhibited similar behavior when co-cultured with L. monocytogenes at 4 °C (death rate K = - 0.67 log10 CFU g-1 day . The death rate K at 10 °C when V. parahaemolyticus co-cultured with L. monocytogenes was -1.62 log10 CFU g-1 day-1 . There was no significant reduction of growth in monoculture experiments. CONCLUSION: This study has revealed that interaction of V. parahaemolyticus and L. monocytogenes should be considered when quantifying risks posed by these pathogens during consumption of seafood products. © 2018 Society of Chemical Industry.
Assuntos
Crustáceos/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento , Alimentos Marinhos/microbiologia , Vibrio parahaemolyticus/crescimento & desenvolvimento , Animais , Técnicas de Cocultura , Culinária , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Refrigeração , Alimentos Marinhos/análiseRESUMO
Oligodendrocyte precursor cell (OPC) maturation requires membrane addition for myelin sheath formation. Since the Rab system has been shown to contribute to membrane addition in other cell types, in this study, we explored the role of Rab in OPC maturation. SiRNA and shRNA techniques and conditional knockout mice provided in vitro and in vivo evidence that Rab10 is involved in OPC maturation and may affect myelination during OPC development.
Assuntos
Células Precursoras de Oligodendrócitos/patologia , Oligodendroglia/fisiologia , Proteínas rab de Ligação ao GTP/deficiência , Animais , Animais Recém-Nascidos , Células Cultivadas , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley , Proteínas rab de Ligação ao GTP/genéticaRESUMO
Oligodendrocyte precursor cell (OPC) development into myelinated oligodendrocytes demands vigorous membrane addition. Since myristoylated alanine-rich C-kinase substrate (MARCKS) reportedly contributes to Ras-associated protein (Rab)-10-associated vesicle insertion into neuronal membranes, we investigated the role of MARCKS in OPC maturation. We found that either knockdown of MARCKS or interruption of its interaction with Rab10 would cause a decrease of the cell membrane area during OPC development. Enhanced MARCKS phosphorylation by Nogo66 or myelin debris treatment inhibited OPC maturation, while its dephosphorylation by protein phosphatase 2 A activator D-erythro-sphingosine promoted OPC development in the presence of myelin debris. Our results demonstrated that MARCKS is involved in OPC maturation by interacting with Rab10.