Metal-organic frameworks (MOFs) have sparked increasing interest in mimicking the structure and function of natural enzymes. However, their catalytic and therapeutic efficiency are unsatisfactory due to the relatively lower catalytic activity. Herein, inspired by nature, a MOF@COF nanozyme has been designed as a high-efficiency peroxidase mimic, with the metallic nodes of MOFs as active centres, the hierarchical nanocavities produced by the growth of covalent organic frameworks (COFs) as binding pockets to form tailored pore microenvironment around active sites for enriching and activating substrate molecules, to perform enhanced bacterial inhibition. Furthermore, the pseudopodia-like surface of the COFs "skin" enabled the system to catch the bacteria effectively for further amplifying the therapeutic efficiency of MOF-based nanozyme. We believe that the present study will not only facilitate the design of novel nanozymes, but also broaden the biological usage of MOF/COF-based hybrid materials.This review addresses nitration reactions of porphyrin derivatives. Simple porphyrins modifications afford valuable intermediates in this area of chemistry. They are useful materials for further transformations, as the NO2 group introduced into parent porphyrin system increases its electrophilic character, thus allowing a broad spectrum of subsequent reactions, e. g. reduction of NO2 to NH2 , subsequent diazotisation, nucleophilic substitution of hydrogen (in ortho-position to NO2 ), a variety of cyclizations, etc. Such reactions are often utilized in the first steps of the designed syntheses, leading to attractive and useful target porphyrin molecules. This approach (via nitro-derivatives) allows synthesizing numerous porphyrin-like compounds of a high degree of complexity, and has thus become one of the methods choice. The substitution by NO2 group can take place at all positions of the porphyrin systems four meso-positions (5, 10, 15, 20) and eight positions β (2, 3, 7, 8, 12, 13, 17, 18).  https://www.selleckchem.com/products/Decitabine.html  The third possibility includes the nitration in meso-aryl rings attached to positions 5, 10, 15, and 20. The latter derivatives (meso-aryl substituted ones) are a large, well-known group of synthetic porphyrins. The nitration reactions described herein follow three various mechanisms (a) radical, (b) via π-cation radicals and π-dications, and (c) electrophilic. All the above cases are discussed in detail. According to our knowledge, this is the first such systematic account concerning these reactions.
  Children with type 1 diabetes (T1D) are at much higher risk of developing celiac disease (CD) than the general population. The aim of the study was to assess the prevalence and differences in clinical presentation of CD in T1D in different regions of the world.
 
  This study is based on the Better control in Pediatric and Adolescent diabeteS Working to crEate cEnTers of Reference (SWEET) database. There were 57 375 patients included in the study, aged ≤18 years from 54 SWEET centers. Only centers with screening for celiac disease were included. Regression models adjusted for age, diabetes duration, and gender and a fixed effect in the models for region was used. Diabetes duration, age at diabetes onset, and sex were presented as unadjusted results.
 
  CD was present in 2652 subjects (4.5%), with different prevalence among regions from 1.9% in Asia/Middle East to 6.9% in Australia/New Zealand. CD was observed more often among females. Comparing children with and without CD, characteristics for those with CD were younger age at diabetes onset (6.3 [3.3; 9.8] vs 8.1 [4.6; 11.3], P < 0.001) and had longer diabetes duration (6.4 [3.6; 9.8] vs 4.8 [2.1; 8.2], P < 0.001). Further, they had lower glycosylated hemoglobin (HbA1c) in Europe and North America/Canada; lower body mass index (BMI)-SD score (BMI-SDS) in southern Europe, North America, and Canada; In most regions daily insulin dose was lower, height-SDS was lower, and the percentage of insulin pump users was higher in children with T1D and CD.
 
  The prevalence and the anthropometric and metabolic consequences of CD in children with T1D differ around the world.
 The prevalence and the anthropometric and metabolic consequences of CD in children with T1D differ around the world.Originating from inhomogeneous Li deposition and dissolution, the formation of dendritic and/or dead Li lies as a fundamental barrier to the practical implementation of Li metal anodes for high-energy Li-ion batteries. Here, an ultraconformal and stretchable solid-electrolyte interphase (SEI) composed of parallelly stacked few-layer defect-free graphene nanosheets, which can deform to remain ultraconformal during the expansion and shrinkage of micro-sized Li metal particles is reported. The shape-adaptive graphene protective skin is prepared via a facile mechanical method followed by Li stripping, which enables fast Li-ion diffusion, and inhibits Li dendrites and Li pulverization. The interlayer slips and wrinkles of the graphene film endow the robust protective skin with high stretchability. This work represents a unique strategy of building ultraconformal and stretchable 2D-materials-based protective skins on the surface of Li metal toward high-energy, long-life, and safe Li metal batteries.Pnictogen-bonding catalysis and supramolecular σ-hole catalysis in general is currently being introduced as the non-covalent counterpart of covalent Lewis acid catalysis. With access to anti-Baldwin cyclizations identified as unique characteristic, pnictogen-bonding catalysis appeared promising to elucidate one of the hidden enigmas of brevetoxin-type epoxide opening polyether cascade cyclizations, that is the cyclization of certain trans epoxides into cis-fused rings. In principle, a shift from SN 2- to SN 1-type mechanisms could suffice to rationalize this inversion of configuration. However, the same inversion could be explained by a completely different mechanism Ring opening with C-C bond cleavage into a branched hydroxy-5-enal and the corresponding cyclic hemiacetal, followed by cascade cyclization under conformational control, including stereoselective C-C bond formation. In this report, a pnictogen-bonding supramolecular SbV catalyst is used to demonstrate that this unorthodox polyether cascade cyclization mechanism occurs.