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1.
J Acoust Soc Am ; 147(4): EL314, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32359269

RESUMO

In deep-sea source localization, some of the existing methods only estimate the source range, while the others produce large errors in distance estimation when estimating both the range and depth. Here, a convolutional neural network-based method with high accuracy is introduced, in which the source localization problem is solved as a regression problem. The proposed neural network is trained by a normalized acoustic matrix and used to predict the source position. Experimental data from the western Pacific indicate that this method performs satisfactorily: the mean absolute percentage error of the range is 2.10%, while that of the depth is 3.08%.

2.
Med Ultrason ; 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32399538

RESUMO

AIMS: In this systematic review and meta-analysis, we discuss the value of grey-scale ultrasonography (US) in diagnosing adhesive capsulitis of the shoulder (ACS). MATERIAL AND METHODS: We retrieved relevant studies from PubMed, Cochrane Library, and Embase before 8 April 2019. We selected 7 studies concerning 446 patients (490 shoulders) that used grey-scale US to diagnose ACS and magnetic resonance imaging (MRI) or arthroscopy as the reference standard. We assessed the diagnostic accuracy of US on the basis of combined sensitivity, specificity, likelihood ratio (LR), and the area under the summary receiver operating characteristic (SROC) curve (AUC). RESULTS: The combined sensitivity, specificity, positive LR and negative LR were found to be 88% (95%CI: 74-95), 96% (95%CI: 88-99), 23.89 (95%CI: 6.31-90.51) and 0.12 (95%CI: 0.05-0.29), respectively. The AUC was 0.97 (95%CI: 0.96-0.98). ACS was diagnosed on the basis of four US features: coracohumeral ligament thickening, inferior capsule/axillary recess capsule thickening, rotator interval abnormality, and restriction of the range of motion. The corresponding sensitivities were 64.4 (95%CI: 48.8-78.1), 82.1 (95%CI: 73.8-88.7), 82.6 (95%CI: 74.1-89.2) and 94.3 (95%CI: 84.3-98.8), respectively, and specificities were 88.9 (95%CI: 76.0-96.3), 95.7 (95%CI: 90.3-98.6), 93.9 (95%CI: 89.8-96.7), and 90.9 (95%CI: 75.7-98.1), respectively. CONCLUSIONS: Our meta-analysis showed that grey-scale US plays a significant role in the diagnosis of ACS. Because of its high sensitivity and specificity, US can be added to the existing clinical diagnosis program.

3.
J Phys Chem Lett ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32407119

RESUMO

Quantitative molecular analysis is usually based on spectrophotometric method using colorimetric assay. Conventional methods, however, rely on the directly uniform absorption of the sample under test, and the detection sensitivity is strictly limited by the length of the absorption cell at the millimeter scale. Here, we report a new methodology for colorimetric assay based on the amplitude holographic interference (AHI) caused by nonuniform absorption of light, with detection sensitivity at the micrometer scale. In our method, the curved surface of the microfluidics results in phase profile with a high diffraction efficiency, and the nonuniform absorption of samples exactly matches with the amplitude modulation in holographic interference. The signal intensity is affected not only by directly sample absorption but also the sequential optical interference behind the liquid level. Both single and multiple wavelength colorimetric analysis of Griess-Saltzman dye (GSD) were carried out using this method, and we found that the sensitivity can be improved by approximately 2-fold higher than the conventional method. This interference-based method would be a useful tool for the colorimetric assay of chemical samples in highly integrated systems with better performance.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32352747

RESUMO

Inspired by the biological process of phosphorylation for which different sites of the same protein may have different activities and functions, we utilized phosphatase-based enzyme-instructed self-assembly (EISA) to construct self-assembled nanomedicine from the precursors with different phosphorylated sites. We found that, although the obtained self-assembling molecules after EISA were identical, the changes of EISA catalytic sites could determine the outcome of molecular self-assembly. The precursor with the phosphorylated site in the middle preorganized before EISA, while the ones with other phosphorylated sites could not preorganize before EISA. After EISA, the preorganized precursor then resulted in more stable and ordered assemblies than those of the others, which showed increased cellular uptake and up to 1.7-fold higher efficacy in an antitumor therapeutic compared to those assembled from unorganized precursors.

5.
J Biol Chem ; 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32371392

RESUMO

Mitochondrial DNA (mtDNA) gene expression is coordinately regulated both pre- and post-transcriptionally, and its perturbation can lead to human pathologies. Mitochondrial ribosomal RNAs (mt-rRNAs) undergo a series of nucleotide modifications after release from polycistronic mitochondrial RNA (mtRNA) precursors, which is essential for mitochondrial ribosomal biogenesis. Cytosine N4-methylation (m4C) at position 839 (m4C839) of the 12S small subunit (SSU) mt-rRNA was identified decades ago; however, its biogenesis and function have not been elucidated in detail. Here, using several approaches, including immunofluorescence, RNA immunoprecipitation and methylation assays, and bisulfite mapping, we demonstrate that human methyltransferase-like 15 (METTL15), encoded by a nuclear gene, is responsible for 12S mt-rRNA methylation at m4C839 both in vivo and in vitro We tracked the evolutionary history of RNA m4C methyltransferases and identified a difference in substrate preference between METTL15 and its bacterial ortholog rsmH. Additionally, unlike the very modest impact of a loss of m4C methylation in bacterial SSU rRNA on the ribosome, we found that METTL15 depletion results in impaired translation of mitochondrial protein-coding mRNAs and decreases mitochondrial respiration capacity. Our findings reveal that human METTL15 is required for mitochondrial function, delineate the evolution of methyltransferase substrate specificities and modification patterns in rRNA, and highlight a differential impact of m4C methylation on prokaryotic ribosomes and eukaryotic mitochondrial ribosomes.

6.
Opt Lett ; 45(9): 2592-2595, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356824

RESUMO

We proposed a data acquisition method to monitor local oscillator (LO) intensity in real time in unidimensional continuous-variable quantum key distribution protocol. Based on this proposed method, the influence of weather conditions on the average transmittance and excess noise is studied, such as relative wetness, visibility, and beam jitter.

7.
Int J Pharm ; : 119409, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32389790

RESUMO

Polymeric micelles (PM) based on poly(ethylene glycol)-b-poly(N-2-benzoyloxypropyl methacrylamide) (mPEG-b-p(HPMA-Bz)) loaded with paclitaxel (PTX-PM) have shown promising results in overcoming the suboptimal efficacy/toxicity profile of paclitaxel. To get insight into the stability of PTX-PM formulations upon storage and to optimize their in vivo tumor-targeted drug delivery properties, we set out to identify a lead PTX-PM formulation with the optimal polymer composition. To this end, PM based on four different mPEG5k-b-p(HPMA-Bz) block copolymers with varying molecular weight of the hydrophobic block (17 to 3 kDa) were loaded with different amounts of PTX. The hydrodynamic diameter was 52±1 nm for PM prepared using polymers with longer hydrophobic blocks (mPEG5k-b-p(HPMA-Bz)17k and mPEG5k-b-p(HPMA-Bz)10k) and 39±1 nm for PM composed of polymers with shorter hydrophobic blocks (mPEG5k-b-p(HPMA-Bz)5k and mPEG5k-b-p(HPMA-Bz)3k). The best storage stability and the slowest PTX release was observed for PM with larger hydrophobic blocks. On the other hand, smaller sized PM of shorter mPEG5k-b-p(HPMA-Bz)5k showed a better tumor penetration in 3D spheroids. Considering better drug retention capacity of the mPEG5k-b-p(HPMA-Bz)17k and smaller size of the mPEG5k-b-p(HPMA-Bz)5k as two desirable design features, we argue that PM based on these two polymers are the lead candidates for further in vivo studies.

8.
iScience ; 23(4): 100985, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32240952

RESUMO

An iron-catalyzed highly anti-Markovnikov selective, enantioselective hydrosilylation of vinylcyclopropanes with PhSiH3 was reported for the preparation of valuable chiral allylic silanes via stereospecific C-C bond cleavage. Simultaneously, difficultly prepared chiral VCPs could be also obtained with moderate to excellent enantioselectivity via this kinetic resolution pathway. The chiral Z-allylic silanes could be converted to various chiral allylic derivatives. A possible mechanism via an iron-silyl species was proposed based on experimental and computational studies.

9.
World J Gastroenterol ; 26(14): 1647-1659, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32327913

RESUMO

BACKGROUND: Microvascular invasion (MVI) is an important prognostic factor affecting early recurrence and overall survival in hepatocellular carcinoma (HCC) patients after hepatectomy and liver transplantation, but it can be determined only in surgical specimens. Accurate preoperative prediction of MVI is conducive to clinical decisions. AIM: To develop and validate a preoperative prediction model for MVI in patients with HCC. METHODS: Data from 454 patients with HCC who underwent hepatectomy at the First Affiliated Hospital of Nanjing Medical University between May 2016 and October 2019 were retrospectively collected. Then, the patients were nonrandomly split into a training cohort and a validation cohort. Logistic regression analysis was used to identify variables significantly associated with MVI that were then included in the nomogram. We evaluated the discrimination and calibration ability of the nomogram by using R software. RESULTS: MVI was confirmed in 209 (46.0%) patients by a pathological examination. Multivariate logistic regression analysis identified four risk factors independently associated with MVI: Tumor size [odds ratio (OR) = 1.195; 95% confidence interval (CI): 1.107-1.290; P < 0.001], number of tumors (OR = 4.441; 95%CI: 2.112-9.341; P < 0.001), neutrophils (OR = 1.714; 95%CI: 1.036-2.836; P = 0.036), and serum α-fetoprotein (20-400 ng/mL, OR = 1.955; 95%CI: 1.055-3.624; P = 0.033; >400 ng/mL, OR = 3.476; 95%CI: 1.950-6.195; P < 0.001). The concordance index was 0.79 (95%CI: 0.74-0.84) and 0.81 (95%CI: 0.74-0.89) in the training and validation cohorts, respectively. The calibration curves showed good agreement between the predicted risk by the nomogram and real outcomes. CONCLUSION: We have developed and validated a preoperative prediction model for MVI in patients with HCC. The model could aid physicians in clinical treatment decision making.

10.
Sci Adv ; 6(15): eaax3969, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32284991

RESUMO

During mitotic prophase, cohesins are removed from chromosome arms by Wapl to ensure faithful sister chromatid separation. However, during female meiosis I, the resolution of chiasmata requires the proteolytic cleavage of cohesin subunit Rec8 along chromosome arms by Separase to separate homologs, and thus the role of Wapl remained unknown. Here, we report that Wapl functions as a regulator of spindle assembly checkpoint (SAC) to prevent aneuploidy in meiosis I. Depletion of Wapl accelerates meiotic progression, inactivates SAC, and causes meiotic defects such as aberrant spindle/chromosome structure and incorrect kinetochore-microtubule (K-MT) attachment, consequently leading to aneuploid eggs. Notably, we identify Bub3 as a binding partner of Wapl by immunoprecipitation and mass spectrometry analysis. We further determine that Wapl controls the SAC activity by maintaining Bub3 protein level and document that exogenous Bub3 restores the normal meiosis in Wapl-depleted oocytes. Together, our findings uncover unique, noncanonical roles for Wapl in mediating control of the SAC in female meiosis I.

11.
Nucleic Acids Res ; 48(9): 4827-4838, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32286661

RESUMO

NONO is a DNA/RNA-binding protein, which plays a critical regulatory role during cell stage transitions of mouse embryonic stem cells (mESCs). However, its function in neuronal lineage commitment and the molecular mechanisms of its action in such processes are largely unknown. Here we report that NONO plays a key role during neuronal differentiation of mESCs. Nono deletion impedes neuronal lineage commitment largely due to a failure of up-regulation of specific genes critical for neuronal differentiation. Many of the NONO regulated genes are also DNA demethylase TET1 targeted genes. Importantly, re-introducing wild type NONO to the Nono KO cells, not only restores the normal expression of the majority of NONO/TET1 coregulated genes but also rescues the defective neuronal differentiation of Nono-deficient mESCs. Mechanistically, our data shows that NONO directly interacts with TET1 via its DNA binding domain and recruits TET1 to genomic loci to regulate 5-hydroxymethylcytosine levels. Nono deletion leads to a significant dissociation of TET1 from chromatin and dysregulation of DNA hydroxymethylation of neuronal genes. Taken together, our findings reveal a key role and an epigenetic mechanism of action of NONO in regulation of TET1-targeted neuronal genes, offering new functional and mechanistic understanding of NONO in stem cell functions, lineage commitment and specification.

12.
FEBS Open Bio ; 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32237066

RESUMO

MiR-155-5p is a key oncogenic microRNA that maintains immune homeostasis and mediates cross-talk between inflammation and tumorigenesis. High expression of programmed death ligand-1 (PD-L1) also plays an important role in immune tolerance in tumors. The present study aimed to explore the relationship between miR-155-5p and PD-L1 in lung adenocarcinoma (LUAD) cells A549 and H1650. The expression levels of miR-155-5p and PD-L1 in LUAD patients were detected by a quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and mimics of miR-155-5p were used to model increased expression in A549 or H1650 cells. After 24 h, we measured levels of PD-L1 by qRT-PCR, western blotting and flow cytometry. In addition, we identified two sites in the PD-L1 3'-UTR (5'-AGCAUUA-3' and 5'-GCAUUAA-3') that can be bound by miR-155-5p using TargetScan (http://www.targetscan.org). Compared to normal tissue, miR-155-5p was overexpressed in tumor tissue (P = 0.0456), whereas the expression of PD-L1 was not significantly different (P = 0.1349). The expression levels of miR-155-5p and PD-L1 were negatively correlated (r = -0.6409, P = 0.0459 and r = -0.7544, P = 0.0117). Exogenous overexpression of miR-155-5p decreased the mRNA, total protein and membrane protein expression levels of PD-L1 both in A549 and H1650 cells (P < 0.05). Taken together, our data suggest that miR-155-5p may suppress the expression of PD-L1 in LUAD.

13.
Cell Immunol ; 352: 104077, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32113615

RESUMO

B7-H3 as a newly identified costimulatory molecule that belongs to B7 ligand family, is broadly expressed in both lymphoid and non-lymphoid tissues. The overexpression of B7-H3 has been verified to be correlated with the poor prognosis and poor clinical outcome of several human cancers. In recent years, researchers reveal that B7-H3 is involved in the pathogenesis of various autoimmune diseases, such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), Sjögren's syndrome (SS), ankylosing spondylitis (AS), etc. In this review, we will discuss the biological function of B7-H3 and summarize the progress made over past years regarding its role in the occurrence and development of autoimmune diseases. The insights gained from these findings could serve as the foundation for future therapies of these diseases.

14.
Stem Cell Res Ther ; 11(1): 124, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183875

RESUMO

BACKGROUND: Crohn's fistula-in-ano is a refractory disease in colorectal and anal surgery. Although autologous adipose-derived stem cell (ADSC) has been used in the treatment of Crohn's fistula-in-ano because of its convenience, non-incision of normal tissue, good tolerance, repeatability, quick recovery, less pain, less damage to anal function, and high quality of life during the perioperative period, there are no reports of its use in China. This is the first clinical trial in China on the treatment of Crohn's fistula-in-ano with ADSC to evaluate its efficacy and safety. METHODS: A total of 22 patients with Crohn's fistula-in-ano were enrolled in this study from January 2018 to October 2018 in the Colorectal Disease Center of Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine. Patients were divided (1:1) into an observation group (ADSC) and a control group (incision-thread-drawing procedure). Primary efficacy endpoint evaluated at months 3, 6, and 12 was the closure of fistulas (closure of all treated fistulas at baseline, confirmed by doctor's clinical assessment and magnetic resonance imaging or transrectal ultrasonography). The patients additionally completed some scoring scales at each follow-up including simplified Crohn's Disease Activity Index (CDAI), Perianal Disease Activity Index (PDAI), Inflammatory Bowel Disease Questionnaire (IBDQ), pain scores with visual analog score (VAS), and Wexner score. The data of inflammatory indexes were also collected. RESULTS: The healing rates of the observation group and the control group at months 3, 6, and 12 were as follows: 10/11(90.9%) vs 5/11(45.5%), 8/11(72.7%) vs 6/11(54.5%), and 7/11(63.6%) vs 6/11(54.5%), respectively. There was no statistical difference between the two groups. In addition, the improvement in simplified CDAI, PDAI, IBDQ, VAS, and Wexner score of the observation group were better than that of the control group at each follow-up. The inflammatory indexes decreased in both the observation group and the control group at 3 months follow-up. And there were no significant differences in the changes of inflammatory indexes between two groups at month 3 compared with the baseline. Safety was maintained throughout month 12, and adverse events occurred in 63.6% of patients in the observation group and 100% patients in the control group. And no adverse event associated with ADSC injection was observed in the study. CONCLUSION: ADSC is a feasible and effective treatment for Crohn's fistula-in-ano, compared with traditional incision and thread-drawing. It can protect anal function of patients, relieve pain, allow quick recovery, be well-tolerated, and improve the quality of life during perioperative period. TRIAL REGISTRATION: China Clinical Trials Registry, No. ChiCTR1800014599. Registered 23 January 2018.

15.
JAMA Surg ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32211839
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 230-234, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027282

RESUMO

OBJECTIVE: to explore the value of capillary electrophoresis in screening ß- thalassemia of children, and to establish the cutoff values of HbA2 and HbF in our laboratory. METHODS: The data of hemoglobin capillary electrophoresis and genetic diagnosis of ß- thalassemia from 886 examined children were retrospectively analyzed. The cutoff values of HbA2 and HbF were determined by ROC curve. RESULTS: The cutoff value of HbA2 screening minor ß- thalassemia was 3.65%, the specificity was 0.996, and the sensitivity was 0.995. The cut-off value of HbF for screening minor ß- thalassemia was 1.45%, specificity was 0.751 and sensitivity was 0.675. Thus, 1 case with codon5 (CCT→C) mutation, 1 case with SEA -HPFH ß deletion, 1 case with - 28 (A→G) merger IVS-Ι-128 (T→G) double heterozygous mutations yet were found out, 1 case with 47 bp ß gene missing has not yet been reported in literature. CONCLUSION: Capillary electrophoresis has more high sensitivity and specificity in the screening of ß- thalassemia in children, especially for the detection of rare ß- thalassemia.


Assuntos
Talassemia , Criança , Eletroforese Capilar , Hemoglobina Fetal , Hemoglobina A2 , Humanos , Estudos Retrospectivos
18.
Nature ; 580(7802): 283-287, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32050258

RESUMO

Corticobasal degeneration (CBD) is a neurodegenerative tauopathy-a class of disorders in which the tau protein forms insoluble inclusions in the brain-that is characterized by motor and cognitive disturbances1-3. The H1 haplotype of MAPT (the tau gene) is present in cases of CBD at a higher frequency than in controls4,5, and genome-wide association studies have identified additional risk factors6. By histology, astrocytic plaques are diagnostic of CBD7,8; by SDS-PAGE, so too are detergent-insoluble, 37 kDa fragments of tau9. Like progressive supranuclear palsy, globular glial tauopathy and argyrophilic grain disease10, CBD is characterized by abundant filamentous tau inclusions that are made of isoforms with four microtubule-binding repeats11-15. This distinguishes such '4R' tauopathies from Pick's disease (the filaments of which are made of three-repeat (3R) tau isoforms) and from Alzheimer's disease and chronic traumatic encephalopathy (CTE) (in which both 3R and 4R isoforms are found in the filaments)16. Here we use cryo-electron microscopy to analyse the structures of tau filaments extracted from the brains of three individuals with CBD. These filaments were identical between cases, but distinct from those seen in Alzheimer's disease, Pick's disease and CTE17-19. The core of a CBD filament comprises residues lysine 274 to glutamate 380 of tau, spanning the last residue of the R1 repeat, the whole of the R2, R3 and R4 repeats, and 12 amino acids after R4. The core adopts a previously unseen four-layered fold, which encloses a large nonproteinaceous density. This density is surrounded by the side chains of lysine residues 290 and 294 from R2 and lysine 370 from the sequence after R4.

19.
J Affect Disord ; 265: 247-254, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090748

RESUMO

BACKGROUND: Recently, abundant evidence indicated proinflammatory cytokines might play a crucial role in pathophysiology and treatment of depression. According to our preclinical research, we propose glycyrrhizic acid (GZA) for an adjunctive treatment owing to its safety, economical and anti-inflammatory profile. METHODS: Eligible participants were recruited and randomly allocated into independent treatment groups of SSRI+GZA (n = 30) and SSRI+PBO (placebo, n = 26). Depressive symptoms and specific serum biomarkers were detected during the 4-week treatment course. Afterward, the relationships between biomarkers and clinical effects were explored. RESULTS: Depressive symptoms relieved more in SSRI+GZA than SSRI+PBO, both at week 2 (P = 0.003) and week 4 (P = 0.016). Meanwhile, at week 4, both response rate (P = 0.035) and remission rate (P = 0.031) acutely became higher in SSRI+GZA compared with SSRI+PBO. Mediation analysis further demonstrated that TNF-α reduction mediated the association between GZA treatment and clinical improvement, the indirect effect lay between 0.124 and 3.514 (95% CI). The exploratory analysis also suggested that the symptomatic improvement existed in patients with high-inflammation (baseline CRP > 3 mg/L) rather than those with low-inflammation (baseline CRP ≤ 3 mg/L). LIMITATIONS: The sample size in this study was not large enough and the follow-up duration was relatively short. CONCLUSIONS: This study offers a novel strategy for the diagnosis, categorization, individualization and prognosis regarding upgrading traditional antidepressant therapy, which is from biomarkers to diagnostic indicator and therapeutic target. Patients are necessary to be classified according to the inflammatory state, those with high levels of baseline inflammation should receive combined treatment with anti-inflammatory agents like GZA.

20.
Artigo em Inglês | MEDLINE | ID: mdl-32037788

RESUMO

Gallium-based room-temperature liquid metals have enormous potential for realizing various applications in electronic devices, heat flow management, and soft actuators. Filling narrow spaces with a liquid metal is of great importance in rapid prototyping and circuit printing. However, it is relatively difficult to stretch or spread liquid metals into desired patterns because of their large surface tension. Here, we propose a method to fabricate a particle-based porous material which can enable the rapid and spontaneous diffusion of liquid metals within the material under a capillary force. Remarkably, such a method can allow liquid metal to diffuse along complex structures and even overcome the effect of gravity despite their large densities. We further demonstrate that the developed method can be utilized for prototyping complex three-dimensional (3D) structures via direct casting and connecting individual parts or by 3D printing. As such, we believe that the presented technique holds great promise for the development of additive manufacturing, rapid prototyping, and soft electronics using liquid metals.

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