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Biomechanics and Modeling in Mechanobiology - The aim of this study was to evaluate the effectiveness of various head injury criteria and associated risk functions in prediction of vulnerable road...  相似文献   
224.
The gut microbiota of intensive care unit (ICU) patients displays extreme dysbiosis associated with increased susceptibility to organ failure, sepsis, and septic shock. However, such dysbiosis is difficult to characterize owing to the high dimensional complexity of the gut microbiota. We tested whether the concept of enterotype can be applied to the gut microbiota of ICU patients to describe the dysbiosis. We collected 131 fecal samples from 64 ICU patients diagnosed with sepsis or septic shock and performed 16S rRNA gene sequencing to dissect their gut microbiota compositions. During the development of sepsis or septic shock and during various medical treatments, the ICU patients always exhibited two dysbiotic microbiota patterns, or ICU-enterotypes, which could not be explained by host properties such as age, sex, and body mass index, or external stressors such as infection site and antibiotic use. ICU-enterotype I (ICU E1) comprised predominantly Bacteroides and an unclassified genus of Enterobacteriaceae, while ICU-enterotype II (ICU E2) comprised predominantly Enterococcus. Among more critically ill patients with Acute Physiology and Chronic Health Evaluation II (APACHE II) scores > 18, septic shock was more likely to occur with ICU E1 (P = 0.041). Additionally, ICU E1 was correlated with high serum lactate levels (P = 0.007). Therefore, different patterns of dysbiosis were correlated with different clinical outcomes, suggesting that ICU-enterotypes should be diagnosed as independent clinical indices. Thus, the microbial-based human index classifier we propose is precise and effective for timely monitoring of ICU-enterotypes of individual patients. This work is a first step toward precision medicine for septic patients based on their gut microbiota profiles.  相似文献   
225.
Sepsis is the most common cause of death in intensive care units. This study investigated the circular RNA (circRNA) and mRNA expression profiles and functional networks of the aortic tissue in sepsis. We established a lipopolysaccharide (LPS)‐induced rat sepsis model. High‐throughput sequencing was performed on the aorta tissue to identify differentially expressed (DE) circRNAs and mRNAs, which were validated by real‐time quantitative polymerase chain reaction (RT‐qPCR). Bioinformatic analysis was carried out and coding and non‐coding co‐expression (CNC) and competing endogenous RNA (ceRNA) regulatory networks were constructed to investigate the mechanisms. In total, 373 up‐regulated and 428 down‐regulated circRNAs and 2063 up‐regulated and 2903 down‐regulated mRNAs were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of mRNAs showed that the down‐regulated genes were mainly enriched in the process of energy generation. CNC and ceRNA regulatory networks were constructed with seven DE circRNAs. The results of functional enrichment analysis of CNC target genes revealed the important role of circRNAs in inflammatory response. The ceRNA network also highlighted the significant enrichment in calcium signalling pathway. Significant alterations in circRNAs and mRNAs were observed in the aortic tissue of septic rats. In addition, CNC and ceRNA networks were established.  相似文献   
226.
Increased expression and activity of cardiac and circulating cathepsin D and soluble fms‐like tyrosine kinase‐1 (sFlt‐1) have been demonstrated to induce and promote peripartum cardiomyopathy (PPCM) via promoting cleavage of 23‐kD prolactin (PRL) to 16‐kD PRL and neutralizing vascular endothelial growth factor (VEGF), respectively. We hypothesized that activation of Hes1 is proposed to suppress cathepsin D via activating Stat3, leading to alleviated development of PPCM. In the present study, we aimed to investigate the role of Notch1/Hes1 pathway in PPCM. Pregnant mice between prenatal 3 days and postpartum 3 weeks were fed with LY‐411575 (a notch inhibitor, 10 mg/kg/d). Ventricular function and pathology were evaluated by echocardiography and histological analysis. Western blotting analysis was used to examine the expression at the protein level. The results found that inhibition of Notch1 significantly promoted postpartum ventricular dilatation, myocardial hypertrophy and myocardial interstitial fibrosis and suppressed myocardial angiogenesis. Western blotting analysis showed that inhibition of Notch1 markedly increased cathepsin D and sFlt‐1, reduced Hes1, phosphorylated Stat3 (p‐Stat3), VEGFA and PDGFB, and promoted cleavage of 23k‐D PRL to 16‐kD PRL. Collectively, inhibition of Notch1/Hes1 pathway induced and promoted PPCM via increasing the expressions of cathepsin D and sFlt‐1. Notch1/Hes1 was a promising target for prevention and therapeutic regimen of PPCM.  相似文献   
227.
DEP domain containing 1(DEPDC1) is involved in the tumorigenesis of a variety of cancers. But its role in tumorigenesis of lung adenocarcinoma (LUAD) is not fully understood. Here, we investigated the role and the underlying mechanisms of DEPDC1 in the development of LUAD. The expression and prognostic values of DEPDC1 in LUAD were analysed by using the data from public databases. Gene enrichment in TCGA LUAD was analysed using GSEA software with the pre‐defined gene sets. Cell proliferation, migration and invasion of A549 cells were examined with colony formation, Transwell and wound healing assays. The function of DEPDC1 in autophagy and RAS‐ERK1/2 signalling was determined with Western blot assay upon DEPDC1 knockdown and/or overexpression in A549, HCC827 and H1993 cells. The results demonstrated that DEPDC1 expression was up‐regulated in LUAD tissues, and its high expression was correlated with unfavourable prognosis. The data also showed that DEPDC1 knockdown impaired proliferation, migration and invasion of A549 cells. Most notably, the results showed that DEPDC1 up‐regulated RAS expression and thus enhanced ERK1/2 activity, through which DEPDC1 could inhibit autophagy. In conclusion, our study revealed that DEPDC1 is up‐regulated in LUAD tissues and plays an oncogenic role in LUAD, and that DEPDC1 inhibits autophagy through the RAS‐ERK1/2 signalling in A549, HCC827 and H1993 cells.  相似文献   
228.
Zhang  Fan  Li  Chunbo  Deng  Kui  Wang  Zhuozhong  Zhao  Weiwei  Yang  Kai  Yang  Chunyan  Rong  Zhiwei  Cao  Lei  Lu  Yaxin  Huang  Yue  Han  Peng  Li  Kang 《Metabolomics : Official journal of the Metabolomic Society》2020,16(3):1-6
Introduction

Untargeted metabolomics intends to objectively analyze a wide variety of compounds. Their diverse physicochemical properties make it difficult to choose an appropriate reconstitution solvent after sample evaporation without influencing the chromatography or hamper column sorbent integrity.

Objectives

The study aimed to identify the most appropriate reconstitution solvent for blood plasma samples in terms of feature recovery, four endogenous compounds, and one selected internal standard.

Methods

We investigated several reconstitution solvent mixtures containing acetonitrile and methanol to resolve human plasma extract and evaluated them concerning the peak areas of tryptophan-d5, glucose, creatinine, palmitic acid, and the phophatidylcholine PC(P-16:0/P-16:0), as well as the total feature count

Results

Results indicated that acetonitrile containing 30% methanol was best suited to match all tested criteria at least for human blood plasma samples.

Conclusion

Despite identifying the mixture of acetonitrile and methanol being suitable as solvent for human blood plasma extracts, we recommend to systematically test for an appropriate reconstitution solvent for each analyzed biomatrix.

  相似文献   
229.
Coronary artery disease (CAD) is one of the biggest threats to human life. Circulating microRNAs (miRNAs) have been reported to be linked to the pathogenesis of CAD, indicating the possible role in CAD diagnosis. The present study aimed to explore the expression profile of plasma miRNAs and estimate their value in diagnosis for CAD. 67 Non‐CAD control subjects and 88 CAD patients were enrolled. We conducted careful evaluation by RT‐PCR analysis, Spearman rank correlation coefficients analysis, Receiver Operating Characteristic (ROC) curves analysis and so on. The plasma levels of six miRNAs known to be related to CAD were measured and three of them showed obvious expression change. Circulating miR‐29a‐3p, miR‐574‐3p and miR‐574‐5p were all significantly increased. ROC analysis revealed the probability of the three miRNAs as biomarkers with AUCs (areas under the ROC curve) of 0.830, 0.792 and 0.789, respectively. They were significantly correlated with each other in CAD patients, suggesting the possibility of joint diagnosis. The combined AUC was 0.915, much higher than each single miRNA. Therefore, our study revealed three promising biomarkers for early diagnosis of CAD. The combination of these miRNAs may act more effectively than individual ones for CAD diagnosis.  相似文献   
230.
Radiotherapy is one of the most important treatments for chest tumours. Although there are plenty of strategies to prevent damage to normal lung tissues, it cannot be avoided with the emergence of radiation‐induced lung injury. The purpose of this study was to investigate the potential radioprotective effects of glucosamine, which exerted anti‐inflammatory activity in joint inflammation. In this study, we found glucosamine relieved inflammatory response and structural damages in lung tissues after radiation via HE staining. Then, we detected the level of epithelial‐mesenchymal transition marker in vitro and in vivo, which we could clearly observe that glucosamine treatment inhibited epithelial‐mesenchymal transition. Besides, we found glucosamine could inhibit apoptosis and promote proliferation of normal lung epithelial cells in vitro caused by radiation. In conclusion, our data showed that glucosamine alleviated radiation‐induced lung injury via inhibiting epithelial‐mesenchymal transition, which indicated glucosamine could be a novel potential radioprotector for radiation‐induced lung injury.  相似文献   
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