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The antibacterial activity of propolis has long been of great interest, and the chemical composition of propolis is directly dependent on its source. We recently obtained a type of propolis from China with a red color. Firstly, the antibacterial properties of this unusual propolis were determined against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). Studies on its composition identified and quantified 14 main polyphenols of Chinese red propolis extracts (RPE); quantification was carried out using liquid chromatography triple quadrupole tandem mass spectrometry (LC-QQQ-MS/MS) and RPE was found to be rich in pinobanksin, pinobanksin-3-acetate, and chrysin. In vitro investigations of its antibacterial activity revealed that its activity against S. aureus and MRSA is due to disruption of the cell wall and cell membrane, which then inhibits bacterial growth. Despite its similar antibacterial activities against S. aureus and MRSA, metabolomic analysis further revealed the effects of RPE on bacteria metabolism were different. The untargeted metabolomic results showed that a total of 7 metabolites in 12 metabolic pathways had significant changes (Fold change > 2, p < 0.05 *) after RPE treatment in S. aureus, while 11 metabolites in 9 metabolic pathways had significant changes (Fold change > 2, p < 0.05 *) after RPE treated on MRSA. Furthermore, RPE downregulated several specific genes related to bacterial biofilm formation, autolysis, cell wall synthesis, and bacterial virulence in MRSA. In conclusion, the data obtained indicate that RPE may be a promising therapeutic agent against S. aureus and MRSA.

Purified vitexin compound 1 (VB1), a novel lignanoid isolated from the seeds of the Chinese herb Vitex negundo, has strong antioxidant abilities and broad antitumor activities. However, little is known about its anti-photoaging effect on the skin and the underlying mechanism. Here, we demonstrated that VB1 significantly attenuates ultraviolet A (UVA)-induced senescence in human dermal fibroblasts (HDFs), as evidenced by senescence-associated β-gal staining, MTT assays, and western blot analysis of the expression of p16 and matrix metalloproteinase-1 (MMP-1). Furthermore, mass spectrometry revealed that VB1 could directly bind to Mitogen-Activated Protein Kinase 1 (MAPK1). Molecular docking and molecular dynamics simulation methods confirmed the mass spectroscopy results and predicted six possible binding amino acids of MAPK1 that most likely interacted with VB1. Subsequent immunoprecipitation analysis, including different MAPK1 mutants, revealed that VB1 directly interacted with the residues, glutamic acid 58 (E58) and arginine 65 (R65) of MAPK1, leading to the partial reversal of UVA-induced senescence in HEK293T cells. Finally, we demonstrated that the topical application of VB1 to the skin of mice significantly reduced photoaging phenotypes in vivo. Collectively, these data demonstrated that VB1 reduces UVA-induced senescence by targeting MAPK1 and alleviates skin photoaging in mice, suggesting that VB1 may be applicable for the prevention and treatment of skin photoaging.

The design goals of VANET(Vehicular Ad-Hoc Networks) are to provide an open public road safety services，and to improve the comfort and efficiency of driving. In VANET, multi channels are employed to transmit safety information and non-safety information respectively. This paper analyzes protocols associating with VANET in detail and proposes an improved multi-channel MAC cooperation scheme. Based on the network simulation software NS2, this paper designs the simulation model for VANET, adds the multi-channel module and application layer module into the network simulation software NS2, and then simulates the single channel and multi-channel, and the improved MAC protocol. From the simulation, it shows that compared with the single channel, multi channels can obtain better throughput, and the improved MAC protocol also has lower latency and message collision ratio than the original standard.

SUMMARY: Understanding how different driving forces have promoted biological divergence and speciation is one of the central issues in evolutionary biology. The Triticum/Aegilops species complex contains 13 diploid species belonging to the A‐, B‐ and D‐lineages and offers an ideal system to address the evolutionary dynamics of lineage fusion and splitting. Here, we sequenced the whole genomes of one S‐genome species (Aegilops speltoides) of the B‐lineage and four S*‐genome diploid species (Aegilops bicornis, Aegilops longissima, Aegilops sharonensis and Aegilops searsii) of the D‐lineage at the population level. We performed detailed comparisons of the five species and with the other four representative A‐, B‐ and D‐lineage species. Our estimates identified frequent genetic introgressions from A‐ and B‐lineages to the D‐lineage species. A remarkable observation is the contrasting distributions of putative introgressed loci by the A‐ and B‐lineages along all the seven chromosomes to the extant D‐lineage species. These genetic introgressions resulted in high levels of genetic divergence at centromeric regions between Ae. speltoides (B‐lineage) and the other four S*‐genome diploid species (D‐lineage), while natural selection is a potential contributor to divergence among the four S*‐genome species at telomeric regions. Our study provides a genome‐wide view on how genetic introgression and natural selection acted together yet chromosome‐regionally divided to promote genomic divergence among the five S‐ and S*‐genome diploid species, which provides new and nuanced insights into the evolutionary history of the Triticum/Aegilops species complex. Significance Statement: The S‐ and S*‐genome section of genus Aegilops has long been considered as the close relatives to B‐subgenome of common wheat (Triticum aestivum). Here we showed that post‐hybridization introgression and natural selection have determined the heterogeneous pattern of genomic divergence of the five species. Given that all the five species can be crossed with polyploid wheat, our new findings, together with the newly generated genome resources, will facilitate exploitation of the S‐ and S*‐genome species in wheat improvement. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the correlation between clinical features and endolymphatic hydrops (EH) in children with sudden sensorineural hearing loss (SSNHL). Methods: We collected 30 SSNHL children aged ≤17 years old, all of whom underwent intravenous gadolinium injection. After 4 hours, inner ear 3-dimensional inversion recovery sequence with real reconstruction (3D-real IR) magnetic resonance imaging was performed. Combined with their medical history such as gender, age, disease course, hearing loss, and so on, the results were analyzed. Results: Different degrees of EH were shown in the vestibule or different turns of cochlea in the affected ears of SSNHL children, and 12 (40%) of 30 children showed positive EH. Age, low and middle frequency hearing loss, and other clinical symptoms such as dizziness and ear fullness have been shown to be related to a certain degree of EH in vestibule or cochlea, whereas no relationship was found between EH and other clinical features such as high-frequency hearing loss, gender, affected side, and tinnitus. Conclusions: Endolymphatic hydrops may not reflect the trend of disease progression over time in children with SSNHL, but the age of onset may be an important factor in the presence or absence of EH. Endolymphatic hydrops may be one of the causes of dizziness and ear fullness but has no obvious connection with the occurrence of tinnitus. Older SSNHL children with dizziness and ear fullness should maintain long-term follow-up to dynamically monitor the changes in EH. [ABSTRACT FROM AUTHOR]

Intravenous drug use (IVDU) can lead to numerous complications from skin abscesses to bacteremia to endocarditis. Here, we present a rare case of acute suppurative thyroiditis as a complication of IVDU, in which a 26-year-old female with a past medical history of IVDU presented to the emergency department for evaluation of a large right sided neck mass. On exam, she had signs of sepsis and thyrotoxicosis. Fine needle aspiration confirmed suppurative thyroiditis. Blood cultures and culture from fine needle aspiration grew Staphylococcus aureus. Patient was treated with 2 weeks of intravenous antibiotics with good resolution of her symptoms.

History of present illness: A 56-year-old male, with a history of hypertension, diabetes, and dyslipidemia, presented with chest pain, fever, and abdominal pain associated with diarrhea, one day post colonoscopy, for which an electrocardiogram (ECG) was done. On further review of history, the patient reported a syncopal episode 2 monthprior. Additionally, he reports a brother who died of sudden cardiac death (SCD) at the age 50. Significant findings: ECG shows an incomplete right bundle branch block (blue arrow) with coved ST segment elevation and an inverted T wave in V1 (red arrow) and ST segment elevation in V2 (black arrow). Discussion: Brugada syndrome is a rare autosomal dominant disease with mutations in the cardiac sodium channel. It is highly associated with ventricular fibrillation and sudden cardiac death (SCD) in predominately middle-aged males.1 The diagnosis is based on a particular ECG pattern described by the Brugada brothers in 1992.2 There are 3 types of Brugada patterns. Our patient’s ECG was consistent with type 1, which is diagnostic and is characterized by a coved ST segment elevation greater than 2mm followed by a negative T wave in the precordial leads.3 Other types include type 2, which shows a saddle-back ST segment elevation with a J-wave greater than 2mm followed by a positive or biphasic T wave, and type 3, which shows ST elevation less than 2 mm in either coved or saddle-back type T wave.4 Patients with Brugada syndrome often present with syncope, non-sustained ventricular tachycardia, atrial fibrillation, or SCD, with a family history of similar episodes. The presence of fever, alcohol intake, sodium channel blockers, cocaine use, and electrolyte imbalances can significantly increase the incidence of arrhythmia.1 The risk of cardiac events in patients with type 1 Brugada and syncope is 1.9% per year and 7.7% per year in those with aborted SCD.3 An implantable cardiac defibrillator (ICD) is the main treatment for symptomatic patients. Those who are asymptomatic or those with type 2 or 3 morphology should undergo further genetic testing and risk stratification for ICD placement.1 Our patient had a negative cardiac catheterization but with his ECG pattern along with his history of syncope and family history of SCD, he was diagnosed with type 1 Brugada syndrome and received an ICD. Topics: EKG, ECG, cardiology, Brugada, arrhythmia