155 research outputs found
Schisandra chinensis extract ameliorates myocardial ischemia/reperfusion injury via TLR4/NF-κB/MyD88 signaling pathway
Purpose: To investigate the effects of Schisandra chinensis extract (SCE) on myocardial ischemiareperfusion (I/R) injury and to elucidate its underlying mechanism of action.
Methods: A rat model of myocardial I/R injury was used. Ischemia was induced by occluding the left anterior descending artery for 30 min and the myocardium was then reperfused for 2 h in Sprague-Dawley rats. Triphenyltetrazolium chloride (TTC) staining was used to measure myocardial infarct size, while the levels of inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA). Western blot assay was conducted to determine protein levels.
Results: TTC staining showed that myocardial I/R injury was ameliorated after SCE treatment. Serum creatine kinase (CK), lactate dehydrogenase (LDH), and malondialdehyde (MDA) levels decreased, whereas superoxide dismutase (SOD) activity increased after SCE treatment. Moreover, seruminterleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) expression levels were reduced after SCE treatment. Furthermore, SCE treatment remarkably downregulated the protein expression levels of Toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB), and myeloid differentiation factor 88 (MyD88).
Conclusion: SCE may exert protective effects against myocardial I/R injury by downregulating TLR4-mediated NF-κB/MyD88 signaling pathway. However, this needs to confirmed in clinical studies.
Keywords: Schisandra chinensis, TLR4/NF-κB/MyD88, Inflammasome, Myocardial ischemiareperfusion injur
Inbreeding produces trade-offs between maternal fecundity and offspring survival in a monandrous spider
Offspring born to related parents often have lower fitness than those born to unrelated parents, a phenomenon termed inbreeding depression. While many species have been shown to rely on pre- and/or postcopulatory mate choice to avoid inbreeding, such research has focused largely on polyandrous rather than monandrous species. The absence of postcopulatory mate choice in monandrous species suggests that precopulatory mate choice should play a more important role in inbreeding avoidance. We used a monandrous wolf spider, Pardosa astrigera, as a model system to investigate whether (1) male spiders respond differently to sibling and nonsibling females; (2) female spiders respond differently to sibling versus nonsibling males; and (3) inbreeding affects females and their offspring. Male courtship behaviour was similar for sibling and nonsibling females; although females were less likely to mate with siblings, over half did mate successfully with them. Sibling-mated females produced fewer offspring from the first egg sac and fewer total offspring, but inbred offspring survived longer in a range of environments than their outbred counterparts. This suggests that the fitness costs of reduced fecundity in sibling-mated females may be offset by higher offspring survivorship. Our results highlight the importance of considering both parent and offspring fitness when addressing the costs of inbreeding, and are the first to document the impact of inbreeding on sexual behaviour and reproductive fitness in a monandrous spider
The Interval-Valued Triangular Fuzzy Soft Set and Its Method of Dynamic Decision Making
A concept of interval-valued triangular fuzzy soft set is presented, and some operations of “AND,” “OR,” intersection, union and complement, and so forth are defined. Then some relative properties are discussed and several conclusions are drawn. A dynamic decision making model is built based on the definition of interval-valued triangular fuzzy soft set, in which period weight is determined by the exponential decay method. The arithmetic weighted average operator of interval-valued triangular fuzzy soft set is given by the aggregating thought, thereby aggregating interval-valued triangular fuzzy soft sets of different time-series into a collective interval-valued triangular fuzzy soft set. The formulas of selection and decision values of different objects are given; therefore the optimal decision making is achieved according to the decision values. Finally, the steps of this method are concluded, and one example is given to explain the application of the method
Effect of holding time on microstructure and mechanical properties of SiC/SiC joints brazed by Ag-Cu-Ti + B4C composite filler
The composite fillers have a number of advantages comparing with the traditional filler metals, and have been widely used for brazing ceramics. However, previous researches mainly focus on the strengthening mechanism of either whiskers or particles. It is still of great interest to investigate the reinforcement effect with the presence of both whiskers and particles. In this study, Ag-Cu-Ti + B4C composite filler was developed to braze SiC ceramics, and effects of holding time on the microstructure evolution and mechanical properties of the joints were investigated in detail. With the prolongation of holding time, the overall thickness of Ti3SiC2 + Ti5Si3 layers adjacent to SiC ceramic was increased correspondingly and the reaction between active Ti and B4C particles was promoted more extensively. The bending strength of the joints increased with holding time until the maximum bending strength of 140 MPa was reached and then decreased dramatically. The hardness and Young's modulus of the joints were characterized by nano-indentation to reveal the strengthening of the brazing seam. In addition, the strengthening mechanism of the joints brazed by the Ag-Cu-Ti + B4C composite filler was proposed on the basis of experimental observation and theoretical analysis
Bemisia Tabaci Q Carrying Tomato Yellow Leaf Curl Virus Strongly Suppresses Host Plant Defenses
The concurrence of tomato yellow leaf curl virus (TYLCV) with the spread of its vector Bemisia tabaci Q rather than B in China suggests a more mutualistic relationship between TYLCV and Q. Here, we investigated the hypothesis that viruliferous B and Q have different effects on plant defenses. We found the fecundity of nonviruliferous B, nonviruliferous Q, viruliferous Q and viruliferous B was 11.080, 12.060, 10.760, and 11.220 respectively on plants previously attacked by the other biotype, however, on their respective noninfested control leaves fecundity was 12.000, 10.880, 9.760, and 8.020 respectively. Only viruliferous B had higher fecundity on viruliferous Q-infested plants than on control plants. The longevity of viruliferous B showed the same phenomenon. At 1 d infestion, the jasmonic acid content in leaves noninfested and in leaves infested with nonviruliferous B, nonviruliferous Q, viruliferous B and viruliferous Q was 407.000, 281.333, 301.333, 266.667 and 134.000 ng/g FW, respectively. The JA content was lowest in viruliferous Q-infested leaves. The proteinase inhibitor activity and expression of JA-related upstream gene LOX and downstream gene PI II showed the same trend. The substantial suppression of host defenses by Q carrying TYLCV probably enhances the spread of Q and TYLCV in China
Igg, Igm and Iga Antibodies against the Novel Polyprotein in Active Tuberculosis
Background
The present study was aimed to evaluate whether IgG, IgM and IgA antibodies levels detected against a novel Mycobacterium tuberculosis polyprotein 38 F-64 F (with 38 F being the abbreviation for 38kD-ESAT6-CFP10 and 64 F for Mtb8.4-MPT64-TB16.3-Mtb8) are suitable for diagnosing active tuberculosis, and for monitoring the efficacy of chemotherapy on TB patients.
Methods
In this study, a total of 371 active TB patients without treatment were selected and categorized into S+/C+ group (n = 143), S-/C+ group (n = 106) or S-/C- group (n = 122). A series of serum samples were collected from 82 active TB patients who had undergone anti-TB chemotherapy for 0–6 months at one month interval. Humoral responses (IgG, IgM and IgA) were determined for the novel Mycobacterium tuberculosis polyprotein using indirect ELISA methods in all of serum samples.
Results
For S+/C+, S-/C+ and S-/C- active tuberculosis patients before anti-TB chemotherapy, the sensitivities of tests based on IgG were 65.7%, 46.2% and 52.5% respectively; the sensitivities based on IgM were 21.7%, 24.5% and 18.9%; and the sensitivities based on IgA were 25.2%, 17.9% and 23.8%. By combination of three isotypes, for all active tuberculosis patients, the test sensitivity increased to 70.4% with the specificity being 91.5%. After anti-TB chemotherapy, there were no significant differences between groups with different courses of anti-TB chemotherapy.
Conclusions
The novel Mycobacterium tuberculosis polyprotein 38 F-64 F represents potential antigen suitable for measuring IgG, IgM and IgA antibodies. However, the serodiagnostic test based on the 38 F-64 F polyprotein appears unsuitable for monitoring the efficacy of chemotherapy
Three-dimensional electron ptychography of organic-inorganic hybrid nanostructures
Three dimensional scaffolded DNA origami with inorganic nanoparticles has been used to create tailored multidimensional nanostructures. However, the image contrast of DNA is poorer than those of the heavy nanoparticles in conventional transmission electron microscopy at high defocus so that the biological and non-biological components in 3D scaffolds cannot be simultaneously resolved using tomography of samples in a native state. We demonstrate the use of electron ptychography to recover high contrast phase information from all components in a DNA origami scaffold without staining. We further quantitatively evaluate the enhancement of contrast in comparison with conventional transmission electron microscopy. In addition, We show that for ptychography post-reconstruction focusing simplifies the workflow and reduces electron dose and beam damage
Quantification of patient-specific coronary material properties and their correlations with plaque morphological characteristics: An in vivo IVUS study
BACKGROUND: A method using in vivo Cine IVUS and VH-IVUS data has been proposed to quantify material properties of coronary plaques. However, correlations between plaque morphological characteristics and mechanical properties have not been studied in vivo.
METHOD: In vivo Cine IVUS and VH-IVUS data were acquired at 32 plaque cross-sections from 19 patients. Six morphological factors were extracted for each plaque. These samples were categorized into healthy vessel, fibrous plaque, lipid-rich plaque and calcified plaque for comparisons. Three-dimensional thin-slice models were constructed using VH-IVUS data to quantify in vivo plaque material properties following a finite element updating approach by matching Cine IVUS data. Effective Young\u27s moduli were calculated to represent plaque stiffness for easy comparison. Spearman\u27s rank correlation analysis was performed to identify correlations between plaque stiffness and morphological factor. Kruskal-Wallis test with Bonferroni correction was used to determine whether significant differences in plaque stiffness exist among four plaque groups.
RESULT: Our results show that lumen circumference change has a significantly negative correlation with plaque stiffness (r = -0.7807, p = 0.0001). Plaque burden and calcification percent also had significant positive correlations with plaque stiffness (r = 0.5105, p \u3c 0.0272 and r = 0.5312, p \u3c 0.0193) respectively. Among the four categorized groups, calcified plaques had highest stiffness while healthy segments had the lowest.
CONCLUSION: There is a close link between plaque morphological characteristics and mechanical properties in vivo. Plaque stiffness tends to be higher as coronary atherosclerosis advances, indicating the potential to assess plaque mechanical properties in vivo based on plaque compositions
Potential health benefits of lowering gas production and bifidogenic effect of the blends of polydextrose with inulin in a human gut model
Polydextrose is a nutrient supplement, which is widely applied in the food industry. The use of polydextrose in combination with prebiotics and probiotics has recently increased, whereas the fermentation properties of its blend have not yet been fully revealed. We evaluated the metabolic profile of polydextrose, inulin, and their blends by a batch in vitro fermentation of fifteen human fecal inocula. After 24 h of fermentation, polydextrose increased the production of gas, ammonia, and several short chain fatty acids, including propionate and butyrate, when compared to its blends, inulin, and fructo-oligosaccharides. Furthermore, polydextrose had the slowest degradation rate of all the carbohydrates tested, consistent with its partial fermentation in the distal colon. The 16S rRNA gene sequencing analysis of the gut microbiome exhibited significantly increased relative abundance of Clostridium_XVIII, Megamonas, Mitsuokella, and Erysipelotrichaceae_incertae_sedis in polydextrose compared to other carbohydrates. On the other hand, the blends of polydextrose and inulin (1:1 or 2:1) showed reduced gas production and similar bifidogenicity to inulin alone. The blends not only had similar alpha-diversity and PCoA to inulin but also had a similar abundance of beneficial bacteria, such as Faecalibacterium and Roseburia, suggesting potential health benefits. Also their low gas production was likely due to the abundance of Faecalibacterium and Anaerostipes, which were negatively correlated with gas production. Additionally, our in vitro fermentation model shows advantages in the large-scale assessment of fermentation performance
Three-dimensional electron ptychography of organic–inorganic hybrid nanostructures
Three dimensional scaffolded DNA origami with inorganic nanoparticles has been used to create tailored multidimensional nanostructures. However, the image contrast of DNA is poorer than those of the heavy nanoparticles in conventional transmission electron microscopy at high defocus so that the biological and non-biological components in 3D scaffolds cannot be simultaneously resolved using tomography of samples in a native state. We demonstrate the use of electron ptychography to recover high contrast phase information from all components in a DNA origami scaffold without staining. We further quantitatively evaluate the enhancement of contrast in comparison with conventional transmission electron microscopy. In addition, We show that for ptychography post-reconstruction focusing simplifies the workflow and reduces electron dose and beam damage
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