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1.
The feasibility and reproducibility of liver stiffness measurements using Supersonic Shear-wave Imaging (SSI) in preterm neonate have not been reported. Our aim was to determine if liver stiffness differs between intra-uterine growth restriction (IUGR) and appropriate for gestational age (AGA) preterm infants with/without cholestasis. We measured liver stiffness (in kPa) in 45 AGA and 18 IUGR preterm infants, and assessed reproducibility in 26 preterms using Intraclass Correlation Coefficients (ICC) and Bland-Altman tests. Liver stiffness values were compared between AGA and IUGR with and without cholestasis and correlated with birth weight. Measurements showed high reproducibility (ICC = 0.94–0.98 for intra-operator, 0.86 for inter-operator) with good agreement (95% limits: -1.24 to 1.24 kPa). During the first postnatal week, liver stiffness was higher in IUGR (7.50 ±1.53 kPa) than in AGA infants (5.11 ±0.80 kPa, p<0.001). After day 8, liver stiffness remained unchanged in AGA but increased progressively in IUGR infants (15.57 ±6.49 kPa after day 21). Liver stiffness was higher in IUGR neonates with cholestasis (19.35 ± 9.80 kPa) than without cholestasis (7.72 ± 1.27 kPa, p<0.001). In conclusion, quantitative liver SSI in preterms is feasible and reproducible. IUGR preterms who will develop cholestasis present high liver stiffness even at birth, before biological cholestasis occurs.  相似文献   
2.
The aim of our study was to evaluate the thermal index (TI) and mechanical index (MI), during the assessment of the fetal heart at the time of first-trimester scan, with different ultrasound machines. This was part of an observational study conducted in patients undergoing routine first-trimester screening. Cases were examined with Voluson E8 or 730Pro scanners using 2–8 MHz transabdominal probes. TI and MI were retrieved from the saved displays while in gray mode, color flow mapping and pulsed-wave (PW) Doppler examinations of the fetal heart and also from the ductus venosus (DV) assessment. We evaluated 552 fetal cardiac examinations, 303 (55%) performed with Voluson E8 and 249 (45%) with Voluson 730Pro ultrasound machines. The gray-scale exam of the heart and the PW Doppler DV assessment had TI values significantly lower for the Voluson E8 group (median, 0.04 vs. 0.2 and 0.1 vs. 0.2, respectively). The MI values from gray-scale and color flow mapping of the heart were significantly lower (median, 0.6 vs, 1.2 and 0.7 vs. 1) and for PW Doppler exam of the tricuspid flow were significantly higher (median 0.4 vs. 0.2) in the Voluson E8 group. The TI values from Doppler examinations of the heart, either color flow or PW imaging and MI values from DV assessment were not significantly different between the two groups. A different (newer) generation of ultrasound equipment provides lower or at least the same safety indices for most of the first-trimester heart examinations.  相似文献   
3.
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS); its cause is unknown. To understand the pathogenesis of MS, researchers often use the experimental autoimmune encephalomyelitis (EAE) mouse model. Here, the aim is to build a proteome map of the biological changes that occur during MS at the major onset sites—the brain and the spinal cord. Quantitative proteome profiling is performed in five specific brain regions and the spinal cord of EAE and healthy mice with high‐resolution mass spectrometry based on tandem mass tags. On average, 7400 proteins per region are quantified, with the most differentially expressed proteins in the spinal cord (1691), hippocampus (104), frontal cortex (83), cerebellum (63), brainstem (50), and caudate nucleus (41). Moreover, region‐specific and commonly expressed proteins in each region are identified and bioinformatics analysis is performed. Pathway analysis reveals that protein clusters resemble their functions in disease pathogenesis (i.e., by inducing inflammatory responses, immune activation, and cell–cell adhesion). In conclusion, the study provides an understanding of the pathogenesis of MS in the EAE animal model. It is expected that the comprehensive proteome map of the brain and spinal cord can be used to identify biomarkers for the pathogenesis of MS.  相似文献   
4.
IntroductionWe have previously identified endogenously citrullinated peptides derived from fibrinogen in rheumatoid arthritis (RA) synovial tissues. In this study, we have investigated the auto-antigenicity of four of those citrullinated peptides, and explored their feasibility to target anti-citrullinated protein/peptide antibodies (ACPA).MethodsThe autoantigenic potential of the fibrinogen peptides was investigated by screening 927 serum samples from the Epidemiological Investigation of RA (EIRA) cohort on a peptide microarray based on the ImmunoCAP ISAC® system. In order to assay for ACPA blocking, two independent pools of purified ACPA were incubated with the respective targeting peptide prior to binding to cyclic citrullinated peptide (CCP)2 using the CCPlus® ELISA kit.ResultsTwo peptides derived from the fibrinogen α chain, Arg573Cit (563-583) and Arg591Cit (580-600), referred to as Cit573 and Cit591, and two peptides from the fibrinogen β chain, Arg72Cit (62-81) and Arg74Cit (62-81) (Cit72 and Cit74), displayed 65 %, 15 %, 35 %, and 53 % of immune reactivity among CCP2-positive RA sera, respectively. In CCP2-negative RA sera, a positive reactivity was detected in 5 % (Cit573), 6 % (Cit591), 8 % (Cit72), and 4 % (Cit74). In the competition assay, Cit573 and Cit591 peptides reduced ACPA binding to CCP2 by a maximum of 84 % and 63 % respectively. An additive effect was observed when these peptides were combined. In contrast, Cit74 and Cit72 were less effective. Cyclization of the peptide structure containing Cit573 significantly increased the blocking efficiency.ConclusionsHere we demonstrate extensive autoantibody reactivity against in vivo citrullinated fibrinogen epitopes, and further show the potential use of these peptides for antagonizing ACPA.  相似文献   
5.

Objective

Obesity is associated with low-grade chronic inflammation. We hypothesized that Roux-en-Y gastric bypass (RYGB) surgery would reduce activation of the NLRP3 inflammasome in metabolically active adipose tissue (AT) of obese rats, and this change would be related to decreases in body weight and improved glycemic control.

Methods

Omental, mesenteric and subcutaneous fat depots were collected from Sprague-Dawley rats: Sham control and RYGB; 90-days after surgery. NLRP3, caspase–1, apoptosis-associated speck-like protein (ASC), IL–1β, IL–18, IL–6 and MCP–1 gene and protein expression were quantified. Glucose metabolism was assessed by oral glucose tolerance test (OGTT).

Results

Compared to Sham surgery controls, RYGB surgery decreased IL–6, MCP–1, NLRP3, IL–18, caspase–1 and ASC in omental fat, and decreased IL–6, MCP1, IL–1β, IL–18, caspase–1 and ASC gene expression in mesenteric fat. We observed differential gene expression between visceral and subcutaneous fat for IL–6 and IL–1β, both being downregulated by RYGB in visceral, and upregulated in subcutaneous depots. These changes in gene expression were accompanied by a decrease in NLRP3, ASC, IL–18, caspase–1 and IL–1β protein expression in omental tissue. We found a positive correlation between caspase–1, ASC, MCP–1, IL–18 and IL–6 gene expression following surgery and glucose AUC response in omental fat, while the change in glucose AUC response correlated with caspase–1 gene expression in subcutaneous fat.

Conclusion

This study demonstrates that bariatric surgery reverses inflammation in visceral adipose tissue by suppressing NLRP3 inflammasome activation. These are the first data to implicate the NLRP3 inflammasome in diabetes remission after RYGB surgery.  相似文献   
6.
BackgroundIn Romania (latitude 48°15’N to 43°40’N), vitamin D supplementation is common practice mostly in infants 0-1 year old. No published information is available regarding epidemiological data on vitamin D status in the Romanian population for a wide age range and geographical territory. In this context, we aimed to evaluate the seasonal and age variation of vitamin D status in a large Romanian population.Methods6631 individuals from across Romania had performed 7544 vitamin D assessments (2012-2014) in a chain of private laboratories. Vitamin D (25-hydroxyvitamin D2 and 25-hydroxyvitamin D3) was measured using High Performance Liquid Chromatography. Vitamin D levels were classified as severe deficiency<10ng/mL, deficiency 10-20ng/mL, insufficiency 21-29ng/mL, sufficiency≥30ng/mL and potentially harmful>100ng/ml.ResultsMale to female ratio was 1:2.9. Age ranged from 0 to 85 years. Mean vitamin D levels increased from April (26.3ng/ml) to September (35.6ng/ml) and decreased from October (33.5ng/ml) to March (24.4 ng/ml). Overall 40% had sufficient vitamin D, while the rest were insufficient 33%, deficient 22%, severely deficient 4% and 1% potentially harmful (of them 81% under 1 year old). Males compared to females showed higher percentages of sufficiency (47% vs. 38%). Children 0- 2 years presented the highest percentage of vitamin D sufficiency (77%). Lowest percentages (21%) of sufficiency were in people 80-84 years.ConclusionIn Romania, suboptimal vitamin D levels are common (59%), especially in older age, wintertime and in women. Vitamin D supplementation would be most warranted from January to April in the Romanian population. 25-hydroxyvitamin D levels>100ng/ml were relatively prevalent in children 0-1 year old (17.3%). This was attributed to supplementation errors and the fact that high-risk individuals were more likely to visit for medical check-up. Nonetheless, it stresses the need to increase awareness of the importance of preventing Vitamin D supplementation administration errors in the young.  相似文献   
7.
The aim of this study was to evaluate the impact that 6‐O‐(3″, 4″‐di‐Otrans‐cinnamoyl)‐α‐ l ‐rhamnopyranosylcatalpol (Dicinn) and verbascoside (Verb), two compounds simultaneously reported in Verbascum ovalifolium, have on tumor cell viability, apoptosis, cell cycle kinetics, and intracellular reactive oxygen species (ROS) level. At 100 µg/mL and 48 hours incubation time, Dicinn and Verb produced good cytotoxic effects in A549, HT‐29, and MCF‐7 cells. Dicinn induced cell‐cycle arrest at the G0/G1 phase and apoptosis, whereas Verb increased the population of subG1 cells and cell apoptosis rates. Furthermore, the two compounds exhibited time‐dependent ROS generating effects in tumor cells (1‐24 hours). Importantly, no cytotoxic effects were induced in nontumor MCF‐10A cells by the two compounds up to 100 µg/mL. Overall, the effects exhibited by Verb in tumor cells were more potent, which can be correlated with its structural features, such as the presence of phenolic hydroxyl groups.  相似文献   
8.
Recently, sodium ion batteries (SIBs) have been widely investigated as one of the most promising candidates for replacing lithium ion batteries (LIBs). For SIBs or LIBs, designing a stable and uniform solid electrolyte interphase (SEI) at the electrode–electrolyte interface is the key factor to provide high capacity, long‐term cycling, and high‐rate performance. In this paper, it is described how a remarkably enhanced SEI layer can be obtained on TiO2 nanotube (TiO2 NTs) arrays that allows for a strongly improved performance of sodium battery systems. Key is that a Li+ pre‐insertion in TiO2 NTs can condition the SEI for Na+ replacement. SIBs constructed with Li‐pre‐inserted NTs deliver an exceptional Na+ cycling stability (e.g., 99.9 ± 0.1% capacity retention during 250 cycles at a current rate of 50 mA g?1) and an excellent rate capability (e.g., 132 mA h g?1 at a current rate of 1 A g?1). The key factor in this outstanding performance is that Li‐pre‐insertion into TiO2 NTs leads not only to an enhanced electronic conductivity in the tubes, but also expands the anatase lattice for facilitated subsequent Na+ cycling.  相似文献   
9.
High-frequency pacing of the left ventricle (LV) free wall causes a dyssynchronous pattern of contraction that leads to progressive heart failure (HF) with pronounced differences in regional contractility. Aim of this study was to evaluate possible changes in brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) mRNA expression in the anterior/anterior lateral region (pacing site, PS) as compared to the infero-septal region (opposite site, OS) and to explore possible association between the contractiling pattern and biomarker expression. Cardiac tissue was collected from minipigs with pacing-induced HF (n = 8) and without (control, n = 6). The samples were selectively harvested from the anterior left ventricular (LV) wall, PS, and from an area remote to the pacing-site, OS. BNP and CNP mRNA expression was evaluated by semi-quantitative polymerase chain reaction (PCR). A significant difference in BNP expression was found in the PS between HF animals and controls (BNP/GAPDH: 0.65 ± 0.11 vs. 0.35 ± 0.04, p = 0.02), but not in the OS (BNP/GAPDH: 0.36 ± 0.05, ns vs. controls). CNP expression was not different compared to controls, although higher levels were observed in the PS and in the OS with respect to the controls (CNP/GAPDH: controls 0.089 ± 0.036, PS 0.289 ± 0.23, OS 0.54 ± 0.16). This finding was in tune with an increase of CNP tissue concentration (controls: 0.69 ± 0.13; PS = 1.56 ± 0.19; OS = 1.70 ± 0.42 pg/mg protein; p = 0.039 controls vs. OS). Higher BNP mRNA expression in the PS is consistent with a reduction in contractile function in this region, while higher CNP mRNA expression in the OS suggests the presence of concomitant endothelial dysfunction in the remote region.  相似文献   
10.
Deamidation of asparagine residues, a post-translational modification observed in proteins, is a common degradation pathway in monoclonal antibodies (mAbs). The kinetics of deamidation is influenced by primary sequence as well as secondary and tertiary folding. Analytical hydrophobic interaction chromatography (HIC) is used to evaluate hydrophobicity of candidate mAbs and uncover post-translational modifications. Using HIC, we discovered atypical heterogeneity in a highly hydrophobic molecule (mAb-1). Characterization of the different HIC fractions using LC/MS/MS revealed a stable succinimide intermediate species localized to an asparagine-glycine motif in the heavy chain binding region. The succinimide intermediate was stable in vitro at pH 7 and below and increased on storage at 25°C and 40°C. Biacore evaluation showed a decrease in binding affinity of the succinimide intermediate compared with the native asparagine molecule. In vivo studies of mAb-1 recovered from a pharmacokinetic study in cynomolgus monkeys revealed an unstable succinimide species and rapid conversion to aspartic/iso-aspartic acid. Mutation from asparagine to aspartic acid led to little loss in affinity. This study illustrates the importance of evaluating modifications of therapeutic mAbs both in vitro and in serum, the intended environment of the molecule. Potential mechanisms that stabilize the succinimide intermediate in vitro are discussed.  相似文献   
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