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1.
Food Chem ; 377: 131996, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34998156

RESUMO

The material basis leading to the rich umami flavor of preserved egg yolk is poorly understood. This study used nano-high-performance liquid chromatography - tandem mass spectrometry (nano-HPLC-MS/MS) to isolate, identify, and screen umami peptides from preserved egg yolk. Five novel umami peptides-AGFMPLP, APYSGY, PPMF, SLSSLMK, and VAMNPVDHPH-were identified. Molecular docking showed that Phe527 on the taste receptor T1R1/T1R3 (T1R1, taste receptor type 1 member 1; T1R3, taste receptor type 1 member 3) was the key interaction site. Hydrogen bonding, electrostatic interactions, and hydrophobic interactions were the main binding forces between T1R1/T1R3 and umami peptides. These results contribute to understanding the umami peptides in preserved egg yolk and the interaction mechanism between umami peptides and umami receptors.

2.
Huan Jing Ke Xue ; 43(1): 267-276, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989511

RESUMO

In order to understand the characteristics and interrelationship of dissolved organic matter (DOM) in interstitial water and overlying water of a landscape river in Suzhou, the characteristics of DOM in interstitial water and overlying water of landscape river sediments in the urban area of Suzhou from July to September after the 2020 flood season were analyzed using the UV-Vis absorption spectrum, high-performance liquid chromatography(HPLC), and fluorescence spectrum combined with the fluorescence region integration method. The results showed that the relative molecular weight of DOM in both the interstitial water and the overlying water was about 1000, and the relative molecular weight tended to increase in the same way over time. Both interstitial water and overlying water had the highest DOM of protein-like content, with a mass fraction that reached 68%-79%. By contrast, the content of humus-like substances was lower, with a mass fraction accounting for approximately 21%-32%, and both were dominated by low-excitation tryptophan. From July to September, a large increase in DOM levels appeared in the interstitial water, followed by a gradual increase in DOM levels in overlying water. These increases might have come from the deposition of algae on the river bottom after summer outbreaks, likely followed by cleavage and release into the interstitial and overlying water. The fluorescence indices (FI) of the interstitial water and overlying water differed more in July and then increased and decreased following the same trend; however, both were greater than 1.2. The authigenic indicator BIX indicator values were all greater than 0.8 and tended toward 1. The humification index (HIX) values were all less than 4; moreover, the interstitial water and overlying water became smaller in the same trend. The same positive correlation was present between the six fluorescent components of DOM (P<0.05), with a significant correlation between low-excitation tyrosine, α254, and HIX. The relationship between interstitial water and DOM in the overlying water in the Suzhou landscape river was closely related, and the interstitial water may be a potential source of DOM in overlying water.


Assuntos
Rios , Água , 2,5-Dimetoxi-4-Metilanfetamina , Espectrometria de Fluorescência
3.
Chin J Integr Med ; 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35023063

RESUMO

OBJECTIVE: To investigate the pharmacodynamic material basis, mechanism of actions and targeted diseases of Salicornia europaea L. (SE) based on the network pharmacology method, and to verify the antidepressant-like effect of the SE extract by pharmacological experiments. METHODS: Retrieval tools including Chinese medicine (CM), PubMed, PharmMapper, MAS 3.0 and Cytoscape were used to search the components of SE, predict its targets and related therapeutic diseases, and construct the "Component-Target-Pathway" network of SE for central nervous system (CNS) diseases. Further, protein-protein interaction (PPI) network, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) function annotation of depression-related targets were analyzed to predict the antidepressant mechanism of SE. Chronic unpredictable mild stress (CUMS) model was used to construct a mouse model with depression-like symptoms. And the animals were randomly divided into 6 groups (n=10) including the normal group (nonstressed mice administered with distilled water), the CUMS group (CUMS mice administered with distilled water), the venlafaxine group (CUMS mice administered with venlafaxine 9.38 mg/kg), SE high-, medium-, and low-dose groups (CUMS mice administered with SE 1.8, 1.35 and 0.9 g/kg, respectively). Then some relevant indicators were determined for experimental verification by the forced swim test (FST), the tail suspension test (TST) and open-field test (OFT). Dopamine (DA) concentration in hippocampus and cerebral cortex, IL-2 and corticosterone (CORT) levels in blood, and nuclear factor E2 related factor 2 (Nrf2), kelch-like epichlorohydrin related protein 1 (Keap1), NAD(P) H dehydrogenase [quinone] 1 (NQO1) and heme oxygenase-1 (HO-1) levels in mice were measured by enzyme linked immunosorbent assay (ELISA) and Western blot respectively to explore the possible mechanisms. RESULTS: The "target-disease" network diagram predicted by network pharmacology, showed that the potential target of SE involves a variety of CNS diseases, among which depression accounts for the majority. The experimental results showed that SE (1.8, 1.35 g/kg) significantly decreased the immobility period, compared with the CUMS group in FST and TST in mice after 3-week treatment, while SE exhibited no significant effect on exploratory behavior in OFT in mice. Compared with CUMS group, the SE group (0.9 g/kg) showed significant differences (P<0.05) in DA levels in the hippocampus and cerebral cortex. In addition, compared with CUMS control group, SE (1.8 g/kg) group showed a significant effect on decreasing the activities of CORT (P<0.05), and serum IL-2 level with no statistical significance. Finally, Western blot results showed that compared with the model group, Nrf2, Keap1, NQO1 and HO-1 protein expressions in SE group (1.8 g/kg) were up-regulated (all P<0.01). CONCLUSION: The SE extract may have an antidepressant effect, which appeared to regulate Nrf2-ARE pathway and increased levels of DA and CORT in the hippocampus and cortex.

4.
Arch Virol ; 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997320

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) is one of the most economically devastating infectious diseases in the global swine industry. A rapid and sensitive on-site detection method for PRRS virus (PRRSV) is critically important for diagnosing PRRS. In this study, we established a method that combines reverse transcription recombinase polymerase amplification (RT-RPA) with a lateral flow dipstick (LFD) for detecting North American PRRSV (PRRSV-2). The primers and probe were designed based on the conserved region of all complete PRRSV-2 genomic sequences available in China (n = 512) from 1996 to 2020. The detection limit of the assay was 5.6 × 10-1 median tissue culture infection dose (TCID50) per reaction within 30 min at 42 °C, which was more sensitive than that of reverse transcription polymerase chain reaction (RT-PCR) (5.6 TCID50 per reaction). The assay was highly specific for the epidemic lineages of PRRSV-2 in China and did not cross-react with pseudorabies virus, porcine circovirus 2, classical swine fever virus, or porcine epidemic diarrhea virus. The assay performance was evaluated by testing 179 samples and comparing the results with those of quantitative RT-PCR (RT-qPCR). The results showed that the detection coincidence rate of RT-RPA and RT-qPCR was 100% when the cycle threshold values of RT-qPCR were < 32. The assay provides a new alternative for simple and reliable detection of PRRSV-2 and has great potential for application in the field.

5.
Zhongguo Zhen Jiu ; 42(1): 41-4, 2022 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-35025156

RESUMO

OBJECTIVE: To compare the therapeutic effect of Tongdu Tiaoqi acupuncture (acupuncture for unblocking governor vessel and regulating qi ) combined with warming acupuncture, Tongdu Tiaoqi acupuncture, abdominal moxibustion and oral tamsulosin hydrochloride sustained release capsule on postoperative urinary retention. METHODS: A total of 120 patients with postoperative urinary retention were randomized into an acupuncture-moxibustion group, an acupuncture group, a moxibustion group and a medication group, 30 cases in each group. Tongdu Tiaoqi acupuncture combined with warming acupuncture were applied in the acupuncture-moxibustion group. Tongdu Tiaoqi acupuncture was applied at Baihui (GV 20), Shuigou (CV 26) etc. in the acupuncture group. Moxibustion was applied at Qihai (CV 6), Guanyuan (CV 4), Shuidao (ST 28) and Sanyinjiao (SP 6) in the moxibustion group. Tamsulosin hydrochloride sustained release capsule was given orally in the medication group. The treatment was once a day, and 5-day treatment was required in each group. Before and after treatment, the residual urine volume of bladder, the visual analogue scale (VAS) score and the time of first urethral catheter removal were observed, and the clinical efficacy was compared in the 4 groups. RESULTS: After treatment, the residual urine volume of bladder was decreased compared before treatment in the 4 groups (P<0.05), and that in the acupuncture-moxibustion group was less than the other 3 groups (P<0.05). After treatment, the VAS scores were decreased compared before treatment in the acupuncture-moxibustion group, the acupuncture group and the moxibustion group (P<0.05), and those in the 3 groups were lower than the medication group (P<0.05). The time of first urethral catheter removal in the acupuncture-moxibustion group was earlier than the other 3 groups (P<0.05). The total effective rate was 93.3% (28/30) in the acupuncture-moxibustion group, which was superior to 63.3% (19/30) in the acupuncture group, 60.0% (18/30) in the moxibustion group and 66.7% (20/30) in the medication group (P<0.05). CONCLUSION: The therapeutic effect of Tongdu Tiaoqi acupuncture combined with warming acupuncture on postoperative urinary retention is superior to simple acupuncture, abdominal moxibustion and tamsulosin hydrochloride sustained release capsule.

7.
Food Chem ; 372: 131319, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818739

RESUMO

In this study, the improvement of gel properties and digestibility of the water-soluble polymer of tea polyphenol (TP)-egg white protein (TEP) under heat induction (HTEP), was studied. Results indicated that the particle size and turbidity of TEP increased with TP concentration, and the absolute value of ζ-potential decreased. After heat induction, the surface hydrophobicity of HTEP decreased with TP concentration, and the degree of protein aggregation increased. Microstructure and T2 showed that the gel structure became compact and stable, and HTEP had a strong water-binding ability. The ionic and disulfide bonds were the main chemical bonds in HTEP. The hardness and disulfide bond increased, but the digestion of HTEP increased initially and then decreased (caused by the change of gel structure). Infrared spectroscopy indicated the mutual conversion of intermolecular and intramolecular ß-sheets. In short, TP could modify egg white gel through forming stable disulfide bonds and dense gel network structures.


Assuntos
Polifenóis , Água , Géis , Polímeros , Chá
8.
Phys Chem Chem Phys ; 24(2): 861-874, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34908073

RESUMO

Src homology-2 domain-containing protein tyrosine phosphatase 1 (SHP1) is mainly restricted to hematopoietic and epithelial cells and widely accepted as a convergent node for oncogenic cell-signaling cascades. The development of efficient methods for rapidly tracing and inhibiting the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of the related disease. With this aim, we designed and synthesized five 2-phenyl-1,3,4-thiadiazole derivatives (PT2, PT5, PT8, PT9 and PT10) here based on the reported SHP1 inhibitors (PT1, PT3, PT4, PT6 and PT7). The photophysical properties and inhibitory activities of these 2-phenyl-1,3,4-thiadiazole derivatives (PT1-PT10) against SHP1 were thoroughly studied from the theoretical simulation and experimental application aspects. The representative compound PT10 exhibited a larger quantum yield than the other molecules because of the smaller geometric relaxation and reorganization energy of the excited state, which was consistent with the results from the fluorescence experiments in organic solvents. In addition, PT10 showed a selective fluorescence response for SHP1 activity and low cytotoxicity in HeLa cells. Lastly, it indicated the potential application in two-photon cell fluorescence imaging in the future according to the calculated excellent two-photon absorption properties. In this contribution, firstly, we offered the fluorescent and activated molecule PT10 against SHP1, which achieved the integration of visualization and inhibitory activity of SHP1 preliminarily at the enzyme molecular level.


Assuntos
Teoria da Densidade Funcional , Inibidores Enzimáticos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/antagonistas & inibidores , Tiadiazóis/farmacologia , Inibidores Enzimáticos/química , Células HeLa , Humanos , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Tiadiazóis/química
9.
Front Psychiatry ; 12: 726038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867516

RESUMO

Introduction: Sleep disorders can affect the overall health and quality of life of patients. This study was conducted to compare the differences of sleep disorders in vestibular migraine (VM) patients and benign paroxysmal positional vertigo (BPPV) patients. Methods: VM patients, BPPV patients, and healthy controls (HCs) were recruited. Pittsburgh sleep quality index and polysomnography monitoring were used as subjective and objective, respectively, evaluation methods to evaluate the sleep quality of participants in the latest month. Results: Fifty-seven BPPV patients, 48 VM patients, and 42 HCs were included in this study. There were 79.16% VM patients, 54.39% BPPV patients, and 14.28% HCs with sleep disorders. The difference in the incidence rate of sleep disorders was significant between VM patients and BPPV patients (p = 0.008) and significantly higher in both the VM group (p < 0.00001) and BPPV group (p = 0.00004) than in the HC groups (14.28%). Compared with BPPV patients, the VM patients had the significantly lower sleep efficiency (p < 0.001) and N3 (p < 0.001) and the significantly higher time of wake-up after sleep onset (p < 0.001), N1 (p < 0.001), and N2 (p < 0.001). Meanwhile, the VM patients had significantly higher incidence rates of severe obstructive sleep apnea hypoventilation syndrome (p = 0.001) and periodic leg movement in sleep (p = 0.016). Conclusion: The incidence rate of sleep disorders was significantly higher in both VM and BPPV patients than in the HC groups. To improve the curative effects, clinicians should pay more attention to the comorbidity of sleep disorders in treating VM and BPPV.

10.
Ultrason Sonochem ; 81: 105857, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34871909

RESUMO

In order to improve the characteristics of egg white protein gel and the stability of egg white protein gel products. In this work, the changes of the texture, physicochemical properties, secondary structure and microstructure of ultrasound modified egg white protein gel (UEP) and tea polyphenols (TP) assisted ultrasound modification of egg white protein gel (TUEP) with different ultrasonic power (0-360 W) were studied. With the increase of ultrasonic power, soluble protein, surface hydrophobicity and disulfide bonds of TUEP and UEP showed an increasing trend. In particular, with the increase of ultrasonic power, the content of intramolecular ß-sheets and α-helices of TUEP showed an increasing trend, and significantly improved the relaxation time and microstructure, thus enhancing TUEP gel stability. In addition, the hardness and water holding capacity (WHC) of TUEP and UEP can be increased by ultrasonic treatment, and when the ultrasonic power reached 120 W, the hardness and WHC reached the maximum. The hardness and WHC of TUEP were significantly better than that of UEP. SDS-PAGE results showed that the peptide chain of protein without being broken under ultrasonic treatment. Ultrasonic treatment can improve the gel strength of egg white protein by promoting the cross-linking of proteins to form a dense gel structure, and egg white protein gel form more disulfide bonds and a more stable gel conformation under TP assisted ultrasound. In conclusion, ultrasound and TP assisted ultrasound modification of egg white protein gel is a reliable technique, which can improve the value of egg white protein in food processing.

11.
Cell Transplant ; 30: 9636897211067804, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34939443

RESUMO

Stem cell transplantation has been applied to treat spinal cord injury (SCI) in clinical trials for many years. However, the clinical efficacies of stem cell transplantation in SCI have been quite diverse. The purpose of our study was to systematically investigate the efficacy of stem cell transplantation in patients with SCI. The PubMed, Web of Science, Ovid-Medline, Cochrane Library, China National Knowledge Infrastructure, VIP, Wanfang, and SinoMed databases were searched until October 27, 2020. Quantitative and qualitative data were analyzed by Review Manager 5.3 and R. Nine studies (n = 328) were included, and the overall risk of bias was moderate. The ASIA Impairment Scale (AIS) grading improvement rate was analyzed in favor of stem cell transplantation group [odds ratio (OR) = 6.06, 95% confidence interval (CI): 3.16-11.62, P < 0.00001]. Urodynamic indices also showed improvement in bladder function. In subgroup analyses, the results indicated that in patients with complete (AIS A) SCI, with the application of cell numbers between n*(107-108), two cell types (i.e., bone marrow-derived mesenchymal stem cells and bone marrow mononuclears), and treatment time of more than 6 months, stem cell transplantation was more beneficial for sensorimotor function (P < 0.05 for all groups). The risk of fever incidence in the stem cell transplantation group was 4.22 (95% CI: 1.7-10.22, P = 0.001), and principal component analysis (PCA) suggested it was more related to transplanted cell numbers. Thus, stem cell transplantation can promote functional recovery in SCI patients. Moreover, the type and quantity of transplanted stem cells and treatment time are important factors affecting the therapeutic effect of stem cell transplantation in SCI. Further studies are needed to evaluate the effects and elucidate the mechanisms of these factors on stem cell therapy in SCI.

12.
Front Cardiovasc Med ; 8: 764599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950713

RESUMO

Background: Acute myocardial damage is common in severe COVID-19. Post-mortem studies have implicated microvascular thrombosis, with cardiovascular magnetic resonance (CMR) demonstrating a high prevalence of myocardial infarction and myocarditis-like scar. The microcirculatory sequelae are incompletely characterized. Perfusion CMR can quantify the stress myocardial blood flow (MBF) and identify its association with infarction and myocarditis. Objectives: To determine the impact of the severe hospitalized COVID-19 on global and regional myocardial perfusion in recovered patients. Methods: A case-control study of previously hospitalized, troponin-positive COVID-19 patients was undertaken. The results were compared with a propensity-matched, pre-COVID chest pain cohort (referred for clinical CMR; angiography subsequently demonstrating unobstructed coronary arteries) and 27 healthy volunteers (HV). The analysis used visual assessment for the regional perfusion defects and AI-based segmentation to derive the global and regional stress and rest MBF. Results: Ninety recovered post-COVID patients {median age 64 [interquartile range (IQR) 54-71] years, 83% male, 44% requiring the intensive care unit (ICU)} underwent adenosine-stress perfusion CMR at a median of 61 (IQR 29-146) days post-discharge. The mean left ventricular ejection fraction (LVEF) was 67 ± 10%; 10 (11%) with impaired LVEF. Fifty patients (56%) had late gadolinium enhancement (LGE); 15 (17%) had infarct-pattern, 31 (34%) had non-ischemic, and 4 (4.4%) had mixed pattern LGE. Thirty-two patients (36%) had adenosine-induced regional perfusion defects, 26 out of 32 with at least one segment without prior infarction. The global stress MBF in post-COVID patients was similar to the age-, sex- and co-morbidities of the matched controls (2.53 ± 0.77 vs. 2.52 ± 0.79 ml/g/min, p = 0.10), though lower than HV (3.00 ± 0.76 ml/g/min, p< 0.01). Conclusions: After severe hospitalized COVID-19 infection, patients who attended clinical ischemia testing had little evidence of significant microvascular disease at 2 months post-discharge. The high prevalence of regional inducible ischemia and/or infarction (nearly 40%) may suggest that occult coronary disease is an important putative mechanism for troponin elevation in this cohort. This should be considered hypothesis-generating for future studies which combine ischemia and anatomical assessment.

13.
Nat Chem Biol ; 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34937912

RESUMO

Sphingosine-1-phosphate receptor 1 (S1PR1) is a master regulator of lymphocyte egress from the lymph node and an established drug target for multiple sclerosis (MS). Mechanistically, therapeutic S1PR1 modulators activate the receptor yet induce sustained internalization through a potent association with ß-arrestin. However, a structural basis of biased agonism remains elusive. Here, we report the cryo-electron microscopy (cryo-EM) structures of Gi-bound S1PR1 in complex with S1P, fingolimod-phosphate (FTY720-P) and siponimod (BAF312). In combination with functional assays and molecular dynamics (MD) studies, we reveal that the ß-arrestin-biased ligands direct a distinct activation path in S1PR1 through the extensive interplay between the PIF and the NPxxY motifs. Specifically, the intermediate flipping of W2696.48 and the retained interaction between F2656.44 and N3077.49 are the key features of the ß-arrestin bias. We further identify ligand-receptor interactions accounting for the S1PR subtype specificity of BAF312. These structural insights provide a rational basis for designing novel signaling-biased S1PR modulators.

14.
Int J Biol Macromol ; 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34843814

RESUMO

Cytochrome P450 monooxygenase (P450 or CYP) plays an important role in the metabolism of insecticides and plant allelochemicals by insects. CYP321B1, a novel Spodoptera litura P450 gene, was identified and characterized. CYP321B1 contains a 1488 bp open reading frame (ORF) that encodes a 495 amino acid protein. In fourth instar larvae, the highest CYP321B1 expression levels were found in the midgut and fat body. In the tannin feeding test, tannin can significantly induce the expression of CYP321B1 in the midgut and fat body of 4th instar larvae. To verify the function of CYP321B1, RNA interference and metabolome analysis were performed. The results showed that silencing CYP321B1 significantly reduced the rate of weight gain under tannin induction. Metabolome analysis showed silencing affected 47 different metabolites, mainly involved in secondary metabolite biosynthesis and amino acid metabolism, including amino acids, lipid fatty acids, organic acids and their derivatives. Henoxyacetic acid and cysteamine are the most highly regulated metabolites, respectively. These findings demonstrate that CYP321B1 plays an important role in tannin detoxification and metabolism. Functional knowledge about metabolite detoxification genes in this major herbivorous insect pest can provide new insights into this biological process and provide new targets for agricultural pest control.

15.
Small ; : e2104200, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34786839

RESUMO

Many enveloped viruses utilize endocytic pathways and vesicle trafficking to infect host cells, where the acidification of virus-containing endosomes triggers the virus-endosome fusion events. Therefore, simultaneous correlation of intracellular location, local pH, and individual virus dynamics is important for gaining insight into viral infection mechanisms. Here, an imaging approach is developed for spatiotemporal quantification of endosomal acidification on the viral journey in host cells using a fluorescence resonance energy transfer based ratiometric pH sensor consisting of a photostable and high-brightness QD, pH-sensitive fluorescent dyes, and virus-binding proteins. Ratiometric analysis of sensor-based single-virus tracking data enables to dissect a two-step endosomal acidification process during the infection of influenza viruses and elucidates the occurrence of the fission and sorting of virus-containing endosomes to recycling endosomes after initial acidification. This technique should serve as a robust approach for in situ quantification of endosomal acidification on the viral journey.

16.
ACS Appl Mater Interfaces ; 13(47): 56035-56044, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34791871

RESUMO

Designing and synthesizing stable electrocatalysts with outstanding performance for water splitting is an arduous and urgent task. Herein, Ru-anchored CoP embedded in N-doped porous carbon nanocubes (Ru-CoP/NCs) is successfully prepared. The Ru-CoP/NC reveals superior hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) properties and stability under alkaline conditions, and the corresponding overpotentials are 22 and 330 mV at 10 mA·cm-2, respectively. The unique N-doped porous carbon nanocube could boost the conductivity, and the electronic structure of CoP can be adjusted by the anchoring of Ru. Therefore, the strong interaction between Ru atoms and CoP improves the hydrogen adsorption on the catalyst, hence boosting the HER/OER performance of the Ru-CoP/NC catalyst. This work provides a facile method to exploit high-performance catalysts for water splitting.

17.
Opt Express ; 29(22): 36616-36633, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34809069

RESUMO

An advanced Dyson imaging spectrometer in the near ultraviolet-visible-near infrared region was designed, fabricated, and evaluated. A lens with reflective coating on the back surface is applying to replace the traditional lens-reflecting grating combination. The design concept and fabrication and alignment methods as well as the results of evaluations of the proposed spectrometer are described in detail. The advanced imaging spectrometer achieves high resolution in both spectral and spatial direction and low stray light at a high numerical aperture in the working waveband. The performance of this modified porotype is analyzed and evaluated. Results show the spectrometer is well suited for the remote sensing of the ocean color as well as for various agriculture and vegetation-related applications.

18.
J Cardiovasc Magn Reson ; 23(1): 126, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34743718

RESUMO

BACKGROUND: Quantitative cardiovascular magnetic resonance (CMR) T1 and T2 mapping are used to detect diffuse disease such as myocardial fibrosis or edema. However, post gadolinium contrast mapping often lacks visual contrast needed for assessment of focal scar. On the other hand, late gadolinium enhancement (LGE) CMR which nulls the normal myocardium has excellent contrast between focal scar and normal myocardium but has poor ability to detect global disease. The objective of this work is to provide a calculated bright-blood (BB) and dark-blood (DB) LGE based on simultaneous acquisition of T1 and T2 maps, so that both diffuse and focal disease may be assessed within a single multi-parametric acquisition. METHODS: The prototype saturation recovery-based SASHA T1 mapping may be modified to jointly calculate T1 and T2 maps (known as multi-parametric SASHA) by acquiring additional saturation recovery (SR) images with both SR and T2 preparations. The synthetic BB phase sensitive inversion recovery (PSIR) LGE may be calculated from the post-contrast T1, and the DB PSIR LGE may be calculated from the post-contrast joint T1 and T2 maps. Multi-parametric SASHA maps were acquired free-breathing (45 heartbeats). Protocols were designed to use the same spatial resolution and achieve similar signal-to-noise ratio (SNR) as conventional motion corrected (MOCO) PSIR. The calculated BB and DB LGE were compared with separate free breathing (FB) BB and DB MOCO PSIR acquisitions requiring 16 and 32 heart beats, respectively. One slice with myocardial infarction (MI) was acquired with all protocols within 4 min. RESULTS: Multiparametric T1 and T2 maps and calculated BB and DB PSIR LGE images were acquired for patients with subendocardial chronic MI (n = 10), acute MI (n = 3), and myocarditis (n = 1). The contrast-to-noise (CNR) between scar (MI and myocarditis) and remote was 26.6 ± 7.7 and 20.2 ± 7.4 for BB and DB PSIR LGE, and 31.3 ± 10.6 and 21.8 ± 7.6 for calculated BB and DB PSIR LGE, respectively. The CNR between scar and the left ventricualr blood pool was 5.2 ± 6.5 and 29.7 ± 9.4 for conventional BB and DB PSIR LGE, and 6.5 ± 6.0 and 38.6 ± 11.6 for calculated BB and DB PSIR LGE, respectively. CONCLUSIONS: A single free-breathing acquisition using multi-parametric SASHA provides T1 and T2 maps and calculated BB and DB PSIR LGE images for comprehensive tissue characterization.

19.
Appl Opt ; 60(32): 10094-10100, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34807114

RESUMO

A novel, to the best of our knowledge, configuration of a Littrow-Offner spectrometer that is off-axis in both the meridian and sagittal planes is proposed. Through theoretical analysis, the relationship between the distance of each element and the aperture is obtained, and the theoretical basis of the sagittal plane off-axis is given. Extra aberrations are corrected by a spherical lens with a convex grating. An example of design has been presented with an f-number of 4 working in 300-500 nm, according to the theory. Its spectral resolution achieves a 0.1 nm at central wavelength, and its volume decreases by 14.5% compared with the traditional Offner spectrometer.

20.
BMJ Open ; 11(11): e049742, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34782340

RESUMO

INTRODUCTION: Follow-up care is important for gastric cancer survivors, but follow-up strategies for gastric cancer survivors remain inconsistent, and compliance of gastric cancer survivors with follow-up care is very low. Understanding the needs and preferences of gastric cancer survivors is conducive to developing appropriate and acceptable follow-up strategies, thereby improving patient compliance. Discrete choice experiments can quantify individual needs and preferences. However, to date, there is no discrete choice experiment on the preferences of gastric cancer survivors, and no studies have examined how gastric cancer survivors make choices based on different characteristics of follow-up. This paper outlines an ongoing discrete choice experiment that aims to (1) explore follow-up service-related characteristics that may affect gastric cancer survivors' choices about their follow-up, (2) elicit how gastric cancer survivors consider the trade-offs among different follow-up service options using discrete choice experiment, (3) determine whether gastric cancer survivors' needs and preferences for follow-up vary due to the economy, politics, technology and culture in different regions. METHODS AND ANALYSIS: Six attributes were developed through a literature review, semistructured interviews and experts and focus group discussions. A fractional factorial design was used to evaluate the interaction between attributes. A multiple logit model will be used to understand the trade-off between the follow-up characteristics of gastric cancer survivors. A mixed logit model will be used to explore the willingness to pay and uptake rate of gastric cancer survivors for follow-up attributes and further explore the preferences of different groups. ETHICS AND DISSEMINATION: This study was approved by the ethics committee of the School of Nursing, Jilin University. The results of this study will be shared through online blogs, policy briefs, seminars and peer-reviewed journal articles and will be used to modify the current strategy of gastric cancer survivors' follow-up services according to economic development and regional culture.

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