Tryptophan-kynurenine profile in pediatric autoimmune hepatitis

Immunologic Research - The impairment of regulatory T cells (Tregs) is a characteristic feature of autoimmune hepatitis (AIH), and the degradation of tryptophan (Trp) to kynurenine (Kyn), by gamma...     

数字病理扫描在颈动脉粥样硬化斑块组织学研究中的应用

目的颈动脉粥样硬化斑块的形成是脑血管病变的独立危险因素之一。对颈动脉内膜剥脱术(carotid endarterectomy,CEA)斑块进行充分的组织学判读和研究,将有助于全面把握CEA斑块的组织学表现,进而推进临床辅助诊断。方法本文我们将运用数字病理扫描仪对CEA斑块的切片经H&E染色后进行扫描,介绍数字病理扫描在CEA斑块组织学研究中的应用。结果经数字病理扫描所得的图片,有助于全面掌握和保存CEA斑块组织切片的全层面信息;在软件的帮助下有助于非常方便地测量斑块内各成分的大小;有助于精确评估斑块的狭窄程度。结论综上,数字病理成像应用于CEA斑块,结合MRI,有助于高效且准确地判读斑块组成和预测斑块稳定性,亦有助于人工智能的训练。     

Effect of Aryl Substituents and Fluorine Addition on the Optoelectronic Properties and Organic Solar Cell Performance of a High Efficiency Indacenodithienothiophene‐alt‐Quinoxaline π‐Conjugated Polymer

A series of donor‐acceptor (D‐A) π‐conjugated polymers, based on indacenodithienothiophene (IDTT) as an electron‐donating unit and quinoxaline as an electron‐deficient moiety, are synthesized via a Pd‐catalyzed Stille cross‐coupling polymerization. Molecular characteristics, photovoltaic parameters, and optoelectronic properties are examined through structural differences corresponding to thienyl versus phenyl side group substitutions on the IDTT and the non‐fluorinated versus the monofluoro quinoxaline derivatives. One of the most important outcome is that the power conversion efficiency (PCE) in the studied polymers is more device architecture dependent (conventional vs inverted) rather than chemical structure dependent. From single junction solar cells based on bulk heterojunction polymer:[6,6]‐phenyl‐C₇₁‐butyric acid methyl ester (PC₇₁BM) systems as the active layer, a maximum PCE of 5.33% has been achieved from the polymer containing the thienyl substituent on the IDTT and one fluorine atom on the quinoxaline. This demonstrates that finding the optimum molecular weight of ThIDTT‐QF or introducing the monofluoro‐quinoxaline in a regioregular motif in the polymer backbone significantly higher PCE can be expected versus the fully optimized high performance PhIDTT‐Q conjugated polymer.     

A Promising Energetic Polymer from Posidonia oceanica Brown Algae: Synthesis,Characterization, and Kinetic Modeling

In this study, microcrystalline cellulose nitrate (MCCN) as energetic polymer is successfully obtained from Posidonia oceanica brown algae (POBA). Fourier transform infrared spectroscopy (FTIR) results show alterations in the intensities of some absorption bands, suggesting a significant difference in the chemical structure between microcrystalline cellulose and the emergent MCCN samples. X‐ray diffraction (XRD) measurements indicate that MCCNs are more crystalline than conventional nitrocellulose (NC). According to scanning electron microscopy (SEM), both NC and MCCN reveal a compact structure and a rough surface. Differential scanning calorimetry (DSC) displays that the thermal degradation of MCCNs shifts to lower temperatures compared to the respective NCs. Furthermore, in comparison with NC samples, MCCN samples exhibit high density, high nitrogen content, low viscosity‐average molecular weight, and good thermal stability. On the other hand, kinetic modeling based on DSC data is carried out by isoconversional integral methods to determine Arrhenius parameters and the decomposition mechanisms. It is found that MCCNs present lower activation energies than conventional NCs with a decrease of ≈6%. Finally, this work opens a new pathway to prepare MCCN from POBA, and it is expected to have applications in several areas such as propellants, energetic binders, and gas generators.     

Engineered Polysaccharides: α‐1,3‐Glucan Acetates Showing Upper Critical Solution Temperature in Organic Solvents

Acetates of α‐1,3‐glucan dissolved in N,N‐dimethyl acetamide/LiCl are prepared by converting the polysaccharide with acetyl chloride, acetic acid anhydride/pyridine, or with acetic acid/N,N′‐carbonyl diimidazole. Values of the degree of substitution for the acetyl groups (DS_Ac) of up to 2.6 are realized. NMR spectroscopic measurements reveal a preferred conversion of the primary hydroxyl group at position 6 followed by positions 2 and 4. Depending on the DS_Ac, the samples may be soluble in solvents of different polarity at room temperature or at elevated temperatures showing upper critical solution temperature at DS of about 2.5. This process is found to be reversible.     

Comprehensive analysis of isolated der(1;7)(q10;p10) in a large international homogenous cohort of patients with myelodysplastic syndromes

The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the new comprehensive cytogenetic scoring system for MDS, chromosome 7 anomalies are no longer generally assigned to poor risk features but are thoroughly separated. However, der(1;7)(q10;p10), hereinafter der(1;7), is merged into the group labeled “any other single” and belongs to the intermediate risk group, just by definition due to lack of adequate clinical data. The aim of our international collaborative was to clarify the “real” prognostic impact of der(1;7) on a homogenous and well‐documented data base. We performed detailed analysis of 63 MDS patients with isolated der(1;7) constituting the largest cohort hitherto reported. Furthermore, clinical data are compared with those of patients with isolated del(7q) and isolated monosomy 7. Median overall survival (OS) of patients with der(1;7) is 26 months (hazard ratio (HR) 0.91 for del(7q) vs der(1;7) and 2.53 for monosomy 7 vs der(1;7)). The der(1;7) is associated with profound thrombocytopenia most probably causing the reduced OS which is in striking contrast to the low risk for AML transformation (HR 3.89 for del(7q) vs der(1;7) and 5.88 for monosomy 7 vs der(1;7)). Molecular karyotyping indicates that der(1;7) is generated in a single step during mitosis and that a chromosomal imbalance rather than a single disrupted gene accounts for malignancy. Thus, the current cytogenetic scoring system assigning isolated der(1;7) to the intermediate risk group is now confirmed by a sufficient data set.     

Advanced Electrocardiogram Analysis in the Amitriptyline‐poisoned Pig Treated with Activated Charcoal Haemoperfusion

Coated activated charcoal haemoperfusion (CAC‐HP) does not reduce the plasma concentration in amitriptyline (AT)‐poisoned pigs. The aim of this non‐blinded, randomized, controlled animal trial was to determine if CAC‐HP reduces the pathological ECG changes caused by AT poisoning. Fourteen female Danish Landrace pigs (mean weight 27.7 kg, range 20–35 kg (CAC‐HP) and 24.4 kg, range 18–30 kg (control group, CG), n = 7 in each group) were included. After randomization, the pigs were anaesthetized and intravenously poisoned with AT. The intervention group underwent 4 hr of CAC‐HP plus standard care (oral activated charcoal). Intervention was compared to standard care alone. From each pig, a 12‐lead ECG and haemodynamic variables were obtained at baseline, at full AT loading dose, before and during CAC‐HP. Baseline ECG variables (RR, PR, QRS, QTc, QTp, QTe, TpTe and TpTe/QT) for lead II, v2 and v5 were not significantly different (F = 0.035–0.297, p‐values 0.421–0.919). Differences within groups over time and between groups were tested by anova repeated measures. For all variables, the time‐plus‐group level of significance revealed a p‐value > 0.05. Severe cardiovascular arrhythmias occurred in both groups with 3 in the CAC‐HP group versus 1 incident with premature death in the CG. The attenuating effect of CAC‐HP to orally instilled activated charcoal alone on AT‐induced ECG alterations did not differ significantly. We conclude that the use of modern CAC‐HP as an adjunctive treatment modality in AT‐poisoned pigs is inadequate.