Screening of the active fractions from the Coreopsis tinctoria Nutt. Flower on diabetic endothelial protection and determination of the underlying mechanism

2020 ◽  
Vol 253 ◽  
pp. 112645
Author(s):  
Yajuan Li ◽  
Chaoran Huang ◽  
Wenwei Fu ◽  
Hong Zhang ◽  
Yuanzhi Lao ◽  
...  
Keyword(s):  
Underlying Mechanism ◽  
Coreopsis Tinctoria

Identification of N-Substituted Triazolo-azetidines as Novel Antibacterials using pDualrep2 HTS Platform

2019 ◽  
Vol 22 (5) ◽  
pp. 346-354
Author(s):  
Yan A. Ivanenkov ◽  
Renat S. Yamidanov ◽  
Ilya A. Osterman ◽  
Petr V. Sergiev ◽  
Vladimir A. Aladinskiy ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Large Scale ◽  
Underlying Mechanism ◽  
Luciferase Assay ◽  
Reporter System ◽  
E Coli ◽  
Starting Point ◽  
High Concentrations ◽  
Mic Value

Aim and Objective: Antibiotic resistance is a serious constraint to the development of new effective antibacterials. Therefore, the discovery of the new antibacterials remains one of the main challenges in modern medicinal chemistry. This study was undertaken to identify novel molecules with antibacterial activity. Materials and Methods: Using our unique double-reporter system, in-house large-scale HTS campaign was conducted for the identification of antibacterial potency of small-molecule compounds. The construction allows us to visually assess the underlying mechanism of action. After the initial HTS and rescreen procedure, luciferase assay, C14-test, determination of MIC value and PrestoBlue test were carried out. Results: HTS rounds and rescreen campaign have revealed the antibacterial activity of a series of Nsubstituted triazolo-azetidines and their isosteric derivatives that has not been reported previously. Primary hit-molecule demonstrated a MIC value of 12.5 µg/mL against E. coli Δ tolC with signs of translation blockage and no SOS-response. Translation inhibition (26%, luciferase assay) was achieved at high concentrations up to 160 µg/mL, while no activity was found using C14-test. The compound did not demonstrate cytotoxicity in the PrestoBlue assay against a panel of eukaryotic cells. Within a series of direct structural analogues bearing the same or bioisosteric scaffold, compound 2 was found to have an improved antibacterial potency (MIC=6.25 µg/mL) close to Erythromycin (MIC=2.5-5 µg/mL) against the same strain. In contrast to the parent hit, this compound was more active and selective, and provided a robust IP position. Conclusion: N-substituted triazolo-azetidine scaffold may be used as a versatile starting point for the development of novel active and selective antibacterial compounds.

scholarly journals Identification and determination of fructooligosaccharides in snow chrysanthemum (Coreopsis tinctoria nutt.)

2021 ◽  
Vol 0 (0) ◽  
pp. 0
Author(s):  
Shao-Ping Li ◽  
Jing Zhao ◽  
Ling-Xiao Chen ◽  
De-Jun Hu ◽  
Wen-Fei Xu
Keyword(s):  
Coreopsis Tinctoria

scholarly journals Pollen-mediated Gene Flow from Coreopsis tinctoria to Coreopsis leavenworthii: Inheritance of Morphological Markers and Determination of Gene Flow Rates as Affected by Separation Distances

2012 ◽  
Vol 137 (3) ◽  
pp. 173-179 ◽  
Author(s):  
Sarah M. Smith ◽  
Zhanao Deng
Keyword(s):  
Gene Flow ◽  
Field Conditions ◽  
Genetic Integrity ◽  
Morphological Marker ◽  
Flow Rates ◽  
Central Florida ◽  
Coreopsis Tinctoria ◽  
Hand Pollination ◽  
Strong Concern

The genus Coreospsis is Florida’s state wildflower. One species, Coreopsis leavenworthii, is nearly endemic to Florida and is highly desirable for use in highway beautification. Maintaining genetic integrity is critical for C. leavenworthii producers, growers, and users. Coreopsis tinctoria is closely related to and shares similar habitats with C. leavenworthii in Florida. Previous studies indicated that the two species could hybridize and the F1 hybrids showed chromosomal aberrations and reduced pollen stainability. There has been strong concern that pollen-mediated gene flow from C. tinctoria could contaminate the gene pool and compromise the genetic integrity of C. leavenworthii. In the current study, hand pollination showed that C. leavenworthii and C. tinctoria were highly compatible. F1 hybrids were fertile and readily produced F2 and BC1 individuals. Inheritance studies indicated that the maroon spot on the ray flower is controlled by a single dominant allele and is homozygous in C. tinctoria. This spot serves as a reliable, easy-to-score morphological marker to detect pollen-mediated gene flow from C. tinctoria to C. leavenworthii. Following a discontinuous design, gene flow studies were conducted under field conditions in central Florida over 2 years. The highest rate of pollen-mediated gene flow from C. tinctoria to C. leavenworthii was 4.2% and occurred when the two species were grown 1.5 m apart. Gene flow from C. tinctoria to C. leavenworthii under field conditions followed a leptokurtic curve. Based on the obtained regression equation, separating the two species by 60 m or more could lower the pollen-mediated gene flow from C. tinctoria to minimal levels and protect the genetic integrity of C. leavenworthii.

Integrated Analysis of Long Non-Coding RNAs and mRNAs Associated With Malignant Transformation of Gastrointestinal Stromal Tumors

2020 ◽  
Author(s):  
Xiaonan Yin ◽  
Yuan Yin ◽  
Lei Dai ◽  
Chaoyong Shen ◽  
Na Chen ◽  
...  
Keyword(s):  
Malignant Transformation ◽  
Gastrointestinal Stromal Tumors ◽  
Underlying Mechanism ◽  
Mitotic Rate ◽  
Integrated Analysis ◽  
Hippo Signaling ◽  
Stromal Tumors ◽  
Tight Association ◽  
Worse Prognosis

Abstract Background: Malignant transformation of gastrointestinal stromal tumors (GISTs) is correlated with poor prognosis; however, the underlying biological mechanism is not well understood. Methods: In the present study, low-risk (LR) GISTs, GISTs categorized as high-risk based on tumor size (HBS), and on mitotic rate (HBM) were collected for RNA sequencing. Candidate hub lncRNAs were selected by Oncomine analysis. Expression of a selected hub lncRNA, DNM3OS, and its correlation with patients’ prognosis were analyzed using FISH staining, followed with the determination of function and underlying mechanism. Results: Our results revealed a series of key pathways and hub lncRNAs involved in the malignant transformation of GISTs. Oncomine analysis revealed a tight association between clinical signatures and DNM3OS and suggested that DNM3OS is a hub lncRNA that is involved in the Hippo signaling pathway. In addition, DNM3OS was upregulated in HBS, HBM, and HBS/M GIST and correlated with worse prognosis in patients with GISTs. In addition, DNM3OS promoted GIST cell proliferation and mitosis by regulating the expression of GLUT4 and CD36. Conclusions: These results improve our understanding of the malignant transformation of GISTs and unveil a series of hub lncRNAs in GISTs.

Reduction of myocardial infarct size by fluvastatin

2003 ◽  
Vol 285 (1) ◽  
pp. H59-H64 ◽  
Author(s):  
C. P. Tiefenbacher ◽  
J. Kapitza ◽  
V. Dietz ◽  
C.-H. Lee ◽  
F. Niroomand
Keyword(s):  
Myocardial Infarct ◽  
Underlying Mechanism ◽  
Cgmp Level ◽  
Control Group ◽  
Myocardial Infarct Size ◽  
Acute Effects ◽  
Triphenyltetrazolium Chloride ◽  
Neutrophil Extravasation ◽  
Reperfusion Period

Statins have a variety of cardioprotective properties following chronic treatment. In contrast, little is known about the acute effects. Reperfusion acutely injures the heart by activation of neutrophils as well as endothelial cells. Because statins are known to influence the processes pathogenetically involved, we hypothesized that acute application of statins attenuates the sequelae of cardiac reperfusion. In rats, myocardial infarction (MI) was induced by ligature of the left coronary artery followed by reperfusion. Myocardial blood flow (MBF) was determined by H2 clearance and regional myocardial function (fractional thickening, FT) by pulsed Doppler. MI size was measured by triphenyltetrazolium chloride (TTC) staining, neutrophil extravasation by determination of myeloperoxidase (MPO) activity, and nitric oxide generation via measurement of cGMP. Treatment with fluvastatin, administered intravenously 20 min before the onset of ischemia, significantly attenuated the decline of FT and MBF at the end of the reperfusion period and significantly reduced MI size. Furthermore, fluvastatin induced a significant reduction of MPO activity and an increase of cGMP level compared with the control group. The effect of fluvastatin was completely abolished following pretreatment of NG-nitro-l-arginine methyl ester (l-NAME). These findings suggest that acute application of fluvastatin reduces MI size and attenuates reperfusion injury. We propose that the underlying mechanism is at least partially an inhibition of inflammation and endothelial dysfunction by preventing the activation and extravasation of neutrophils.

scholarly journals Pyrene-Functionalized Polyacetylenes: Synthesis and Photoluminescence Property

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1366
Author(s):  
Tanxiao Shen ◽  
Nan Jiang ◽  
Xiao’a Zhang ◽  
Lirong He ◽  
Xian Hua Lang ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Photoluminescence Property ◽  
Underlying Mechanism ◽  
Polymer Structure ◽  
Intramolecular Energy Transfer ◽  
Spectroscopic Techniques ◽  
Excimer Emission ◽  
Polymer Backbone ◽  
Chemical Structures

Four pyrene-functionalized polyacetylenes were designed and prepared through a typical post-polymerization modification route, which is the highly efficient reaction between activated ester and primary anime groups. The chemical structures of the resultant polymers were characterized with multiple spectroscopic techniques and the data indicated the successful functionalization of the polyacetylenes. The introduction of the pyrene moieties into the polymer structure allowed us to investigate the interactions between the polymer backbone and side chains. For the mono-substituted polyacetylenes, both the monomer and excimer emission features of the pyrene groups could be recorded, while for the di-substituted polyacetylenes, the fluorescence from the pyrene excimer vanished and the fluorescence intensity from the pyrene monomer decreased, the fluorescence from the polymer chain predominated the emission features. The concomitant energy transfer from the pyrene monomer and excimer to poly(diphenylacetylene) backbone was associated with the underlying mechanism. In addition to the substitution modes, the linkage between the poly(diphenylacetylene) backbone and the pyrene moiety also played a significant role in the determination of the emission species. A long alkyl spacer was beneficial to the pyrene monomer emission while a short one may be helpful to the formation of the excimer and intramolecular energy transfer.

A Correlational Analysis of Symmetry between the Arrowhead and Featherhead Müller-Lyer Illusions

Perception ◽  
1983 ◽  
Vol 12 (2) ◽  
pp. 119-129 ◽  
Author(s):  
June Adam ◽  
Layna Bateman
Keyword(s):  
Partial Correlation ◽  
Underlying Mechanism ◽  
Correlational Analysis ◽  
Stimulus Figure ◽  
Difference Score ◽  
Methodological Issues ◽  
Baseline Levels ◽  
Correlation Techniques

Correlational methods were used to investigate symmetry of effect for the arrowhead and featherhead versions of the Müller-Lyer figure. Two control figures were compared in the determination of baseline levels for measurement of the illusions: a shaft presented without any inducing context, and a shaft with vertical inducing lines attached. In addition, results based on difference-score measures of the illusions were contrasted with results obtained by partial-correlation techniques. Overall, when one considers the results for either one of the arrowhead or featherhead versions, the evidence favours a common underlying mechanism. However, results across the two versions suggest that the mechanisms for the two versions differ fundamentally. In weighing the different kinds of evidence contributing to this conclusion, methodological issues were raised. By obtaining two judgments for each stimulus figure from a large number of subjects, it was possible to demonstrate not only that conventional difference-score measures of illusions are highly unreliable, but also that they can yield biased results.

Techno-Optimism and Rational Superstition

2017 ◽  
Vol 21 (2) ◽  
pp. 342-362 ◽  
Author(s):  
Alexander Wilson ◽  
Keyword(s):  
Rational Expectations ◽  
Underlying Mechanism ◽  
Rational Agents ◽  
The Past ◽  
Retroactive Effect ◽  
The World ◽  
The Future ◽  
State Of Affairs ◽  
Common Understanding

This article examines some of the implications of technological optimism. I first contextualize, historically and culturally (Christopher Nolan’s Interstellar [2014] is considered as a particularly salient example), some contemporary variants of techno-optimism in relation to the equally significant contemporary exemplars of techno-pessimism, skepticism and fatalism. I show that this techno-optimism is often instrumentalized in the sense that the optimistic outlook as such is believed to have some influence on the evolving state of affairs. The cogency of this assumption is scrutinized. I argue that in the absence of explicit probabilities, such optimism presupposes some form of retro-causation, where the future is held to somehow have a retroactive effect on the past. This suggests that the underlying mechanism by which techno-optimism is supposed to be instrumental in bringing about the future is fundamentally superstitious. Such superstition, of course, goes against our common understanding of reason and rationality, for adopting rational expectations about the world requires that we avoid the emotional over-determination of our assessments. I show that applied reason is conceptually entangled with this superstitious optimism in the continued successes of technology. The article thus reveals a curious sense in which reason is intrinsically superstitious. I offer an evolutionary explanation for this, showing that the biological origins of reason will by nature tend to produce rational agents which are superstitiously bound to realism and causality, and thus implicitly optimistic about technology’s capacity to overcome contingency.

scholarly journals Observation of cavitation governing fracture in glasses

2021 ◽  
Vol 7 (14) ◽  
pp. eabf7293
Author(s):  
Lai-Quan Shen ◽  
Ji-Hao Yu ◽  
Xiao-Chang Tang ◽  
Bao-An Sun ◽  
Yan-Hui Liu ◽  
...  
Keyword(s):  
Crack Propagation ◽  
Disordered Systems ◽  
Underlying Mechanism ◽  
Material Failure ◽  
Self Organized ◽  
Fundamental Understanding ◽  
Glassy Materials ◽  
Cavitation Behavior ◽  
Fracture Morphologies

Crack propagation is the major vehicle for material failure, but the mechanisms by which cracks propagate remain longstanding riddles, especially for glassy materials with a long-range disordered atomic structure. Recently, cavitation was proposed as an underlying mechanism governing the fracture of glasses, but experimental determination of the cavitation behavior of fracture is still lacking. Here, we present unambiguous experimental evidence to firmly establish the cavitation mechanism in the fracture of glasses. We show that crack propagation in various glasses is dominated by the self-organized nucleation, growth, and coalescence of nanocavities, eventually resulting in the nanopatterns on the fracture surfaces. The revealed cavitation-induced nanostructured fracture morphologies thus confirm the presence of nanoscale ductility in the fracture of nominally brittle glasses, which has been debated for decades. Our observations would aid a fundamental understanding of the failure of disordered systems and have implications for designing tougher glasses with excellent ductility.

Exercise-induced laryngeal obstruction in children and adolescents: are we listening?

2020 ◽  
pp. edpract-2020-319454
Author(s):  
Liam Welsh ◽  
Alessandra Giannini ◽  
John Massie
Keyword(s):  
Children And Adolescents ◽  
Underlying Mechanism ◽  
Visual Observation ◽  
Exertional Dyspnoea ◽  
Hyperventilation Syndrome ◽  
Laryngeal Obstruction ◽  
Exercise Limitation ◽  
Direct Visual Observation ◽  
Exercise Induced

Exertional dyspnoea among children and adolescents is a common presenting complaint to general practitioners. Exertional dyspnoea is most commonly attributed to exercise-induced bronchoconstriction (EIB), but there are several other causes including hyperventilation syndrome, breathlessness associated with normal exercise limitation and exercise-induced laryngeal obstruction (EILO). The symptoms of EILO include stridor, throat tightness and difficulty on inspiration. If these are mistaken for EIB, children will receive asthma therapy. The underlying mechanism of EILO includes closure of the larynx during high-intensity exercise, which causes a reduction in airflow and breathlessness. This phenomenon is often associated with a background of psychological stress. Historically, a diagnosis of EILO has been considered ‘rare’ though this may be a reflection of under-recognition. Direct visual observation via laryngoscopy is the gold standard for diagnosis of EILO; however, this is rarely available even in specialised centres. Nevertheless, the diagnosis can usually be made by recognising the characteristic clinical pattern. Here we provide recommendations for appropriate investigations for the determination of EILO, together with suggested treatment.

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