Effects of chronic dexamethasone exposure on bile acid metabolism and cecal epithelia function in goats

Bile acids (BAs) are synthesized in the liver via the oxidation of cholesterol and further metabolized by microbiota in the gut, where they simultaneously impact gut function. In the present study, 10 goats were randomly divided into 2 groups; 1 group was injected with dexamethasone (Dex; 0.2 mg/kg), and the other group was injected with saline as the control (Con) for 21 d. Expression levels of key genes and proteins in the liver and gut mucosa were analyzed and compared to investigate the impact of chronic stress on BA metabolism and related functions in ruminants. The results revealed that Dex decreased plasma total BAs (TBAs) concentration (P < 0.05) but increased TBA concentration in the cecal digesta (P < 0.05). Total cholesterol in the liver decreased moderately in response to Dex. The protein expression of cytochrome P450 family 7 subfamily A member 1 and cytochrome P450 family 27 subfamily A member 1, 2 enzymes that control BA synthesis in the liver, remained unchanged by Dex administration (P > 0.05). The expression of several genes in the cecal mucosa encoding epithelial tight junction proteins, including occludin (P < 0.05), tight junction protein 1 (P < 0.01), and claudin 1 (P < 0.05), increased significantly in response to Dex, and expression of defensin beta 1, which can strengthen the innate immune system, was also upregulated (P < 0.05). In addition, BAs increased the expression of the Solute Carrier family 9 member A 2 (P < 0.01) that encodes a sodium hydrogen exchanger. These results suggest that the Dex-induced disruption of BA homeostasis might be mediated through a liver-independent pathway in goats, and the Dex-induced accumulation of TBAs in the cecal digesta may improve volatile fatty acid transportation and mucosal defense.

Analysis of the correlation between the neutrophil-lymphocyte ratio in peripheral blood and perioperative myocardial damage in pediatric patients with frequent ventricular premature beat

OBJECTIVE

The objective of the present study was to investigate the relationship between the neutrophil-lymphocyte ratio (NLR) in peripheral blood and myocardial damage in pediatric patients with frequent ventricular premature beat (FVPB), and provide a reference for myocardial preservation in these patients.

PATIENTS AND METHODS

A total of 212 pediatric patients who were treated in the Department of Cardiology, Xuzhou Children's Hospital between December 2014 and March 2016 for FVPB, were selected. The results of routine blood exam, and levels of cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) in patients after the onset of FVPB were analyzed, and NLR was calculated. According to NLR levels, patients were divided into four groups using quartiles.

RESULTS

With increases of NLR, the proportion of patients with a history of hypertension and ejection fraction < 50% increased gradually, and white blood cells (WBCs), the peaks of CK-MB and cTnI, and serum creatinine levels were significantly increased (p<0.05, p<0.01). There were no significant differences (p>0.05) in age, sex, body mass index, serum creatinine before treatment, fasting blood glucose, TG, TC, LDL-C, and HDL-C among the four groups. Multiple stepwise regression analysis showed that for patients with FVPB, NLR in peripheral blood was positively correlated with the peak of cTnI (r=0.538, p<0.05). NLR was positively correlated with levels of WBCs (r=0.661, p<0.05) and there was no correlation between NLR and history of hypertension, ejection fraction, and the laboratory results of creatinine peak and CK-MB. The differences were not statistically significant (p>0.05). However, the peak of cTnI was positively correlated with the levels of WBCs (r=0.189, p=0.003).

CONCLUSIONS

NLR and WBCs in patients with FVPB are positively related to the peak of cTnI. NLR may serve as an excellent marker that reflects myocardial damage in pediatric patients with FVPB.

Calculation for tensile strength and fracture toughness of granite with three kinds of grain sizes using three-point-bending test

Tensile strength and fracture toughness, important parameters of the rock for engineering applications are difficult to measure. Thus this paper selected three kinds of granite samples (grain sizes = 1.01mm, 2.12mm and 3mm), used the combined experiments of physical and numerical simulation (RFPA-DIP version) to conduct three-point-bending (3-p-b) tests with different notches and introduced the acoustic emission monitor system to analyze the fracture mechanism around the notch tips. To study the effects of grain size on the tensile strength and toughness of rock samples, a modified fracture model was established linking fictitious crack to the grain size so that the microstructure of the specimens and fictitious crack growth can be considered together. The fractal method was introduced to represent microstructure of three kinds of granites and used to determine the length of fictitious crack. It is a simple and novel method to calculate the tensile strength and fracture toughness directly. Finally, the theoretical model was verified by the comparison to the numerical experiments by calculating the nominal strength σ_n and maximum loads P_max.

A Novel Complementation Assay for Quick and Specific Screen of Genes Encoding Glycerol-3-Phosphate Acyltransferases

The initial step in glycerolipid biosynthesis, especially in diverse allopolyploid crop species, is poorly understood, mainly due to the lack of an effective and convenient method for functional characterization of genes encoding glycerol-3-phosphate acyltransferases (GPATs) catalyzing this reaction. Here we present a novel complementation assay for quick and specific characterization of GPAT-encoding genes. Its key design involves rational construction of yeast conditional lethal gat1Δgat2Δ double mutant bearing the heterologous Arabidopsis AtGPAT1 gene whose leaky expression under repressed conditions does not support any non-specific growth, thereby circumventing the false positive problem encountered with the system based on the gat1Δgat2Δ mutant harboring the native episomal GAT1 gene whose leaky expression appears to be sufficient for generating enough GPAT activities for the non-specific restoration of the mutant growth. A complementation assay developed based on this novel mutant enables quick phenotypic screen of GPAT sequences. A high degree of specificity of our assay was exemplified by its ability to differentiate effectively GPAT-encoding genes from those of other fatty acyltransferases and lipid-related sequences. Using this assay, we show that Arabidopsis AtGPAT1, AtGPAT5, and AtGPAT7 can complement the phosphatidate biosynthetic defect in the double mutants. Collectively, our assay provides a powerful tool for rapid screening, validation and optimization of GPAT sequences, aiding future engineering of the initial step of the triacylglycerol biosynthesis in oilseeds.

Comprehensive analysis of aberrantly expressed profiles of lncRNAs and miRNAs with associated ceRNA network in muscle-invasive bladder cancer

Although initially thought to be transcriptional noise, long noncoding RNAs (lncRNAs) are gaining increased attention in human cancers as its diversity function. At present, lncRNAs are regarded as the main part of competing endogenous RNA (ceRNA) network due to its regulation on protein-coding gene expression by acting as miRNA sponges. However, functional roles of lncRNA-mediated ceRNAs in muscle-invasive bladder cancer remain unclear. To clarify relevant potential mechanisms, here we comprehensively compared the expression profiles of mRNAs, lncRNAs and miRNAs between 322 muscle-invasive bladder cancer tissues and 19 non-tumor bladder tissues, based on the Cancer Genome Atlas (TCGA). A total of 22 lncRNAs were identified as aberrantly expressed and had correlations with tumorigenesis and/or progression of muscle-invasive bladder cancer (|log2FoldChange| > 1.5, corrected P value < 0.01). 6 out of the 22 dysregulated lncRNAs functioned as prognostic biomarkers for patients with muscle-invasive bladder cancer according to the overall survival analysis (P value < 0.05). Finally, a dysregulated lncRNA-associated ceRNA network was successfully constructed, which inculdes five muscle-invasive bladder cancer-specific lncRNAs, nine miRNAs and 32 mRNAs. In summary, our study identified novel lncRNAs as candidate prognostic biomarkers and potential therapeutic targets for muscle-invasive bladder cancer, based on large-scale sample size. More importantly, the newly identified ceRNA network will be beneficial for improving the understanding of lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of muscle-invasive bladder cancer.

Downregulation and pro-apoptotic effect of hypoxia-inducible factor 2 alpha in hepatocellular carcinoma

The role of HIF-2α in hepatocellular carcinoma (HCC) is unclear. The aim of the present study was to investigate the expression pattern and role of HIF-2α in HCC patients. Immunohistochemical staining and western blotting analyses were applied to detect the protein level of HIF-2α in 206 paired HCC and peritumoral tissues. Kaplan-Meier survival and Cox proportional hazard regression analyses were performed to identify risk factors for overall survival and recurrence-free survival in these patients. The function of HIF-2α was studied in HCC cells and in vivo models. We found that the protein levels of HIF-2α in HCC tissues were lower than in peritumoral tissues, and were negatively correlated with tumor size (P < 0.05). Kaplan-Meier survival and univariate analysis revealed that HCC patients with high HIF-2α protein levels had longer overall survival (P < 0.05). Over-expression of HIF-2α induced apoptosis in HCC cells and increased the levels of pro-apoptotic proteins, Bak, ZBP-89 and PDCD4, whereas the inhibition of HIF-2α expression achieved opposite results. The findings were confirmed in a mouse HCC xenograft model. In conclusion, our study revealed that HIF-2α was decreased and played an anti-tumorigenic role in HCC.

New insights into sorafenib resistance in hepatocellular carcinoma: Responsible mechanisms and promising strategies

It is disappointing that only a few patients with hepatocellular carcinoma (HCC) obtain a significant survival benefit from the sorafenib treatment, which is currently regarded as a first-line chemotherapeutic therapy in patients with advanced HCC. Most patients are highly refractory to this therapy. Therefore, it is necessary to identify resistant factors and explore potential protocols that can be used to overcome the resistance or substitute sorafenib once the resistance is formed. In fact, a growing body of studies has been focusing on the resistance mechanisms or the method to overcome it. The limitation of sorafenib efficacy has been partially but not fully elucidated. Moreover, some protocols have shown encouraging outcomes but still need to be further verified in clinical trials. In this review, we summarize the recent findings on the potential mechanisms that contribute to sorafenib resistance and discuss strategies that can be used to improve the treatment outcome.

Correlation between NFATC1 gene polymorphisms and congenital heart disease in children

OBJECTIVE

To analyze the links between NFATC1 gene polymorphism and congenital heart disease in children.

PATIENTS AND METHODS

In the present study, we selected 85 children patients with congenital heart disease who were hospitalized from February 2013 to February 2015 as research subjects (observation group), and 92 healthy subjects as control group. Restriction fragment length polymorphism (RFLP) was used for analysis of NFATC1 gene in samples from each group.

RESULTS

The distribution of NFATC1 genotype and allele between the observation group (children with congenital heart disease) and the control group showed no significant difference (p >0.05), but AA, GG genotypes, and allele frequency between pathological samples of children with congenital heart disease and the control group displayed significant difference (p <0.05) (X2 = 16.04, p <0.05; X2 = 16.29, p <0.05). Further analyses showed that AA, GG, AG genotype and allele frequency among children with congenital heart disease in observation group also showed a difference, i.e., homozygote (AA, GG) ratio in children with severe congenital heart disease is relatively high.

CONCLUSIONS

There is a correlation between NFATC1 genes and the incidence of congenital heart disease in children, and a correlation between different genotypes and allele frequency and the incidence of the disease.

Evolving safety practices in the setting of modern complex operating room: role of nurses

Operating room (OR) nursing previously referred to patient care provided during the intra-operative phase and the service provided within the OR itself. With the expansion of responsibilities of nurses, OR nursing now includes pre-operative and post-operative periods, therefore peri-operative nursing is accepted as a nursing process in OR in the contemporary medical literature. Peri-operative nurses provide care to the surgical patients during the entire process of surgery. They have several roles including those of manager or a director, clinical practitioner (scrub nurse, circulating nurse and nurse anesthetist), educator as well as researcher. Although, utmost priority is placed on insuring patient safety and well-being, they are also expected to participate in professional organization, continuing medical education programs and participating in research activities. A Surgical Patient Safety Checklist formulated by the World Health Organization serves as a major guideline to all activities in OR, and peri-operative nurses are key personnel in its implementation. Communication among the various players of a procedure in OR is key to successful patient outcome, and peri-operative nurses have a central role in making it happen. Setting up of OR in military conflict zones or places that suffering a widespread natural disaster poses a unique challenge to nursing. This review discusses all aspects of peri-operative nursing and suggests points of improvement in patient care.

Profiling single-guide RNA specificity reveals a mismatch sensitive core sequence

Targeting specificity is an essential issue in the development of CRISPR-Cas technology. Using a luciferase activation assay, off-target cleavage activity of sgRNA was systematically investigated on single nucleotide-mismatched targets. In addition to confirming that PAM-proximal mismatches are less tolerated than PAM-distal mismatches, our study further identified a "core" sequence that is highly sensitive to target-mismatch. This sequence is of 4-nucleotide long, located at +4 to +7 position upstream of PAM, and positioned in a steric restriction region when assembled into Cas9 endonuclease. Our study also found that, single or multiple target mismatches at this region abolished off-target cleavage mediated by active sgRNAs, thus proposing a principle for gene-specific sgRNA design. Characterization of a mismatch sensitive "core" sequence not only enhances our understanding of how this elegant system functions, but also facilitates our efforts to improve targeting specificity of a sgRNA.

Correlation analysis between GNAS2 gene polymorphisms in children with arrhythmia

OBJECTIVE

The objective of the present study was to analyze the correlation between GNAS2 gene polymorphisms and children with arrhythmia.

PATIENTS AND METHODS

We followed 89 children with arrhythmia treated in our hospital from April 2013 to April 2015, comprising the observation group, while 92 healthy subjects were taken as the control group. We analyzed polymorphisms of the GNAS2 gene from both groups by restriction fragment length polymorphism (RFLP).

RESULTS

There were no significant differences (p>0.05) in GNAS2 genotype or allelic distribution between the observation group and control group. However, there were significant differences in the gene frequency of homozygotes (TT and GG) and alleles between the control group and samples from children with arrhythmia (p<0.05) (X2=16.57, p<0.05; X2=17.48, p<0.05). Further study of samples from both groups indicate that gene frequency of homozygous (TT and GG) or heterozygous (TG) genes and alleles also had differences, indicating that homozygotes (TT and GG) are in relatively high proportion among patients with severe cases of arrhythmia.

CONCLUSIONS

Morbidity in patients with arrhythmia is related to GNAS2 gene polymorphisms. Differences in genotype and allele frequency are related to the severity of illness.

[Phosphatase and tensin homolog deleted on chromosome ten/phosphatidyl Inositol 3-kinase/vascular endothelial growth factor signaling pathway changes in the rabbit Kawasaki disease model]

OBJECTIVE

To observe the changes of phosphatase and tensin homolog deleted on chromosome ten(PTEN)/ phosphatidyl Inositol 3-kinase(PI3K)/ vascular endothelial growth factor(VEGF)signaling pathway in a rabbit Kawasaki disease model.

METHODS

Model of Kawasaki disease was established in weanling Japanese big-eared rabbits with 10% bovine serum venous injection (2.5 ml/kg, 2 times, and 2 week's interval) through the ear. Twenty four rabbits were divided into 4 groups: control group (without injection of 10% bovine serum albumin, six rabbits); 1 day group (sacrificed a the second day after the establishment of Kawasaki disease models, six rabbits); 7 day group (sacrificed at the seventh day after establishment of Kawasaki disease model, six rabbits); 30 day group (sacrificed at the thirtieth day after establishment of Kawasaki disease model, six rabbits). Pathological analysis was performed on coronary artery tissue samples. The express of PTEN and PI3K were detected by immunohistochemistry. The levels of VEGF and CK were also examined with ELISA and white blood cells were counted.

RESULTS

(1) Coronary artery of model groups was thinner, distorted and had enlarged lumen. (2) PTEN expression in 1 d group, 7 d group and 30 d group were 58.5 ± 12.9, 73.2±9.9 and 109.6 ± 24.4, respectively, significantly higher than in the control group (25.5 ± 6.9, P<0.01 or 0.05). (3) The express of PI3K was significantly upregulated in 1 d group(57.2±11.1)and 7 d group(39.9±4.8) compared to control group(19.1±3.5, P<0.01 or 0.05). The expression level of PI3K in 30 d group was 18.8 ± 7.5, which was similar as control group (P>0.05) and significantly lower than 1 d and 7 d group (both P<0.05). (4) Similarly, the level of VEGF in 1 d group, 7 d group ((89.1 ± 15.5) ng/L, (76.9±9.9) ng/L) were significantly higher while it was significantly lower in 30 d group ((19.8 ± 4.4)ng/L) compared with the control group ((33.9 ± 6.7) ng/L, P<0.01 or 0.05). The level of VEGF in 7 d group was significantly lower than in 1 d group (P<0.05) and the level of VEGF was significantly lower in 30 d group than in 7 d group (P<0.01). (5)Creatine kinase levels were significantly higher in 30 d group than in control group (P<0.05) and there were no significantly different between control group, 1 d group and 7 d group(all P>0.05). (6)White blood cell count were significantly higher in 1 d group, 7 d group and 30 d group than in control group (all P<0.01).

CONCLUSION

The level of PTEN/PI3K/VEGF signaling pathway change after establishment of rabbit Kawasaki disease model and the signaling pathway might be involved in this model.

A High-sugar High-fat Diet Induced Metabolic Syndrome Shows some Symptoms of Alzheimer's Disease in Rats

OBJECTIVES

Cases of sporadic Alzheimer's disease (SAD) are the predominant form of the age-related dementia. New evidence suggests that metabolic syndrome (MS), a metabolic disorder, is an initiating factor of some SAD cases. A high-sugar high-fat diet could cause MS, we aimed to investigate whether it could directly lead to SAD.

MEASUREMENTS

The characteristic molecules of AD (hippocampus Aβ and Tau) were tested by using ELISA and western blotting to confirm the happening hallmarks of AD in brain. MS and inflammation related biochemical indicators were measured using immunological method. Proteins associated with the insulin resistance signal pathway (JNK, PI-3K, AKT, GSK-3β, GLUT3) were evaluated using western blotting method. The levels of reactive oxygen species (ROS) were measured by immunofluorescence method.

RESULTS

Expressions of hippocampus Aβ, phosphorylation-Tau (p-Tau), inflammatory factors and p-JNK, Gsk-3βwere higher in the model rats than those in the control rats and expressions of p-PI3K, p-AKT and GLUT3 were reversed.

CONCLUSIONS

The MS model animals, which can induce the characteristics symptoms of AD, and therefore it may be preliminarily considered that the AD pertains to the MS-related diseases.

Paucity of Nanolayering in Resin-Dentin Interfaces of MDP-based Adhesives

Self-assembled nanolayering structures have been reported in resin-dentin interfaces created by adhesives that contain 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). These structures have been hypothesized to contribute to bond durability. The objective of the present study was to determine the extent of nanolayering in resin-dentin interfaces after application of commercialized 10-MDP-containing self-etch and universal adhesives to human dentin. Seven commercialized adhesives were examined: Adhese Universal (Ivoclar-Vivadent), All-Bond Universal (Bisco, Inc.), Clearfil SE Bond 2, Clearfil S3 Bond Plus, Clearfil Universal Bond (all from Kuraray Noritake Dental Inc.), G-Premio Bond (GC Corp.), and Scotchbond Universal (3M ESPE). Each adhesive was applied in the self-etch mode on midcoronal dentin according to the respective manufacturer's instructions. Bonded specimens (n = 6) were covered with flowable resin composite, processed for transmission electron microscopy, and examined at 30 random sites without staining. Thin-film glancing angle X-ray diffraction (XRD) was used to detect the characteristic peaks exhibited by nanolayering (n = 4). The control consisted of 15%wt, 10%wt, and 5%wt 10-MDP (DM Healthcare Products, Inc.) dissolved in a mixed solvent (ethanol and water weight ratio 9:8, with photoinitiators). Experimental primers were applied to dentin for 20 s, covered with hydrophobic resin layer, and examined in the same manner. Profuse nanolayering with highly ordered periodicity (~3.7 nm wide) was observed adjacent to partially dissolved apatite crystallites in dentin treated with the 15% 10-MDP primer. Three peaks in the 2θ range of 2.40° (3.68 nm), 4.78° (1.85 nm), and 7.18° (1.23 nm) were identified from thin-film XRD. Reduction in the extent of nanolayering was observed in the 10% and 5% 10-MDP experimental primer-dentin interface along with lower intensity XRD peaks. Nanolayering and characteristic XRD peaks were rarely observed in specimens prepared from the commercialized adhesives. The sparsity of nanolayering in resin-dentin interfaces created by commercialized adhesives challenges its clinical effectiveness as a mechanism for improving bond longevity in dentin bonding.

Correlation between magnetic resonance perfusion weighted imaging of radiation brain injury and pathology

We used magnetic resonance perfusion weighted imaging and pathological evaluation to examine different stages of radiation-induced brain injury and to investigate the correlation between the relative cerebral blood volume (rCBV) ratio and vascular endothelial growth factor (VEGF). Thirty adult rats were randomly divided into 2 groups: control and radiation group. The control group was not subjected to irradiation. The irradiation group rats were examined by magnetic resonance imaging and magnetic resonance perfusion weighted imaging at 1, 3, 6, 9, and 12 months after radiation treatment. We measured the rCBV, mean transit time, and time to peak. Hematoxylin and eosin staining, immunohistochemical staining, and electron microscopy were performed. VEGF absorbance was evaluated by immunohistochemical staining. Compared with the control group, the differences in rCBV, mean transit time, time to peak, and VEGF absorbance after 3 months were statistically significant (P < 0.05). rCBV was positively correlated with VEGF (r = 0.94, P < 0.05). Magnetic resonance perfusion weighted imaging can reflect pathophysiological changes in brain tissue after irradiation. Decreased expression of VEGF plays a critical role in the pathogenesis of radiation-induced brain injury.