Physicochemical Properties and Biological Activity of Active Films Based on Corn Peptide Incorporated Carboxymethyl Chitosan

Active films based on carboxymethyl chitosan incorporated corn peptide were developed, and the effect of the concentration of corn peptide on films was evaluated. Physicochemical properties of the films, including thickness, opacity, moisture content, color, mechanical properties, water vapor permeability, and oil resistance, were measured. Biological activities of the films, including the antioxidant and antibacterial activities, were characterized in terms of 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging activity, reducing power, the total antioxidant activity, and the filter disc inhibition zone method. The results indicated that the incorporation of corn peptide caused interactions between carboxymethyl chitosan and corn peptide in Maillard reaction and gave rise to the films light yellow appearance. Compared with the Control, the degree of glycosylation, browning intensity, thickness, opacity, tensile strength, antioxidant activity, and antibacterial activity of films were increased, but the elongation, vapor permeability, and oil resistance of films were decreased. The films based on corn peptide and carboxymethyl chitosan can potentially be applied to food packaging

Application of postmortem computed tomography angiography to settle a medical dispute after aortic dissection surgery: a forensic case report

Abstract Background In the present case, we applied postmortem computed tomography angiography (PMCTA) in a medical dispute involving sudden death after cardiovascular surgery. Case presentation A 39-year-old man underwent aortic arch replacement combined with stented elephant trunk implantation surgery under extracorporeal circulation. All vital signs were stable and he was arranged for discharge seven days after surgery. Several days later, the patient was sent back to the hospital for chest pain and poor appetite. Unfortunately, his condition worsened and he ultimately died. PMCT scanning detect pericardial effusion. Family members suspected that the surgical sutures were not dense enough, causing the patient’s postoperative bleeding and resulting in cardiac tamponade and death. PMCTA was performed before autopsy, which showed pericardial effusion. However, postmortem angiography with simulated blood pressure showed no leakage of contrast agent, which guided the subsequent autopsy and histological examinations. Conclusions While many previous postmortem imaging case reports have shown positive results that provided evidence of medical malpractice, the current case excludes the possibility of physician negligence and reasonably settles the medical dispute from another perspective. In short, the PMCTA approach we describe here was an effective tool that can be applied to certain medical-related forensic cases

The complete mitochondrial genome of the edible mushroom Grifola frondosa

The culinary-medicinal mushroom Grifola frondosa is widely cultivated in East Asia. In this study, the complete mitochondrial genome of G. frondosa was determined using Illumina sequencing. The circular molecule was 197,486 bp in length with a content of 25.01% GC, which was one of the largest mitochondrial genomes in the order Polyporales. A total of 39 known genes encoding 13 common mitochondrial genes, 24 tRNA genes, 1 ribosomal protein s3 gene (rps3), and 1 DNA polymerase gene (dpo) were predicted in this genome. The phylogenetic analysis showed that G. frondosa clustered together with Sparassis crispa, Laetiporus sulphureus, Wolfiporia cocos, and Taiwanofungus camphoratus. The complete mitochondrial genome reported here may provide new insight into genetic information and evolution for further studies

Levels and spatial distributions of levoglucosan and dissolved organic carbon in snowpits over the Tibetan Plateau glaciers

In this study, we collected 60 snowpit samples in nine glaciers from the northern to the southern Tibetan Plateau (TP), to study the levels and spatial distributions of levoglucosan and dissolved organic carbon (DOC). The lowest concentration of levoglucosan was found in the Yuzhufeng (YZF) glacier with a mean value of 0.24 ± 0.08 ng mLâ\u88\u92 1, while the highest concentration of levoglucosan was detected in the Gurenhekou (GRHK) glacier with a mean value of 11.72 ± 15.61 ng mLâ\u88\u92 1. However, the average DOC concentration in TP glaciers were comparable, without significant regional differences. The levoglucosan/DOC ratio ranged from 0.02 to 6.03% in the Tibetan Plateau glaciers. This ratios and the correlations between levoglucosan and DOC suggested that biomass burning products contributed only marginally to DOC levels in the TP glaciers. Moreover, the analysis of air mass backward trajectories suggested that levoglucosan and DOC in TP glaciers should be transported from the northwestern TP, internal TP, Central Asia, South and East Asia regions