Glycocalyx shedding is markedly increased during the acute phase of Takotsubo cardiomyopathy

Background: Acute myocardial infarction (AMI) and other forms of myocardial acute oxidative stress are associated with variable “shedding” of the endothelial glycocalyx (GCS) which can be quantitated ex vivo by release into plasma of glycocalyx components such as Syndecan-1 (SD-1). Previous studies have implicated release of both catecholamines and BNP as potential accentuating factors in GCS: since these are prominent aspects of the pathogenesis of Takotsubo cardiomyopathy (TTC), we hypothesised that TTC is associated with increased GCS and the extent of GCS is predictable on the basis of NT-proBNP and catecholamine releases. Methods: SD-1 concentrations were measured in 48 TTC patients acutely and after 3 months, and compared with those in 12 healthy controls, and 17 patients with AMI. Correlations were sought between SD-1 levels markers of severity of TTC episodes in individual patients. Results: Acute SD-1 concentrations in TTC patients were elevated significantly (p < 0.0001, 1-way ANOVA) compared to control values. There were no significant correlations between SD-1 concentrations and any markers of severity of acute TTC episodes, such as NT-proBNP or catecholamine release. Over 3 months, SD-1 concentrations fell significantly (p = 0.0002) to approximately the same values as in control subjects. Conclusions: TTC is associated acutely with a marked increase in GCS. Potentially, GCS might contribute to increased coronary vascular permeability in TTC, thus dissociating development of myocardial oedema from severity of associated inflammation. Prevention of GCS represents a potential therapeutic option in TTC

Impaired tissue responsiveness to B-type natriuretic peptide in heart failure: biochemical bases.

Release of the B-type natriuretic peptide (BNP) is increased in heart failure (HF). Physiologically, BNP exerts natriuretic, diuretic, vasodilator and cardioprotective effects. A number of clinical investigations carried out with synthetic BNP for the treatment of HF have suggested that BNP-based restoration of homeostasis is inadequate. This equivocal clinical benefit of a recombinant BNP in HF raises the possibility of attenuated BNP response. The objective of this thesis is an examination of three aspects of BNP-related cardiovascular pathophysiology. The first issue tested was the effect of BNP in isolated neutrophils of control subjects via neutrophil superoxide (O₂⁻) generation. The second issue was integrity of BNP effects in acute and chronic HF patients, and the third was maintenance of BNP effect in the acute phase of Tako-tsubo cardiomyopathy (TTC), a form of “stress-induced” cardiomyopathy and another condition associated with increased BNP release. The study utilized the technique of electron paramagnetic resonance spectroscopy to quantitate the extent of O₂⁻ generation from isolated neutrophils. In control subjects, the data showed significant suppression of O₂⁻ generation in PMA- and fMLP-stimulated neutrophils. This effect was not affected by either age or gender of the study population. The effect of BNP was mimicked by a cell-permeable cGMP analog (8-pCPT-cGMP) and partially restored by a protein kinase G (PKG) inhibitor KT5823. Furthermore, BNP inhibited the fMLP-induced phosphorylation of the NAD(P)H oxidase subunit p47phox at ser345. These findings led to the conclusion that BNP suppression of O₂⁻ generation is mediated by the cGMP-PKG signaling pathway. The studies concerning HF patients had two major components: (a) examination of the BNP effect in acute HF patients and (b) determination of changes in effect with chronic treatment of such patients. Studies with acute HF patients showed a significant attenuation of BNP effects on suppressing neutrophil O₂⁻ generation compared with control subjects. However, 8-p-CPTcGMP effects were retained, which indicates that BNP effects were attenuated at the level of natriuretic peptide receptor level. Furthermore, the effect of BNP on inhibition of the fMLP-induced phosphorylation of p47phox at ser345 was lost in acute HF patients. Comparison of the acute and chronic HF patients revealed a partial restoration of BNP effects, especially in younger patients. TTC is associated with acute release of BNP into plasma as a result of inflammatory change in the heart. It was found that BNP effect was attenuated similarly in TTC patients and acute HF patients. The residual effect was not associated with either patients’ inflammatory status or catecholamine release. In summary, this study identified that (1) In control subjects without diagnosed cardiovascular disease, BNP suppressed the release of the inflammatory modulator O₂⁻ from isolated neutrophils by attenuating NAD(P)H oxidase assembly; (2) This effect of BNP was lost in patients with acute HF, but recovers partially with chronic treatment of HF. (3) In TTC patients, attenuation of BNP effect was also present. These data suggest that marked elevation of plasma concentration of BNP limits its physiological anti-inflammatory effects.Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 201

Design of Intelligent Fast Switch Controller Based on CPLD

In view of the large volume, complex structure and many transmission links of the current circuit breaker operating mechanism, a new type of electromagnetic actuator and electronic controller are used to shorten the operation time. This paper introduces the hardware and software design of an intelligent fast switching controller based on CPLD. The hardware circuit design of the controller is mainly described, including power supply conversion and charging voltage monitoring, switch state monitoring, control command monitoring, relay output, LED indicator and split switch driving module. The optocoupler isolation is realized between input and output, and the thyristor module is used to drive the capacitor discharge. The feasibility of the design circuit is verified by the actual sampling waveform, which has the advantages of high-speed operation, intelligent control, high technical performance and reliable operation

Design of Intelligent Fast Switch Controller Based on CPLD

In view of the large volume, complex structure and many transmission links of the current circuit breaker operating mechanism, a new type of electromagnetic actuator and electronic controller are used to shorten the operation time. This paper introduces the hardware and software design of an intelligent fast switching controller based on CPLD. The hardware circuit design of the controller is mainly described, including power supply conversion and charging voltage monitoring, switch state monitoring, control command monitoring, relay output, LED indicator and split switch driving module. The optocoupler isolation is realized between input and output, and the thyristor module is used to drive the capacitor discharge. The feasibility of the design circuit is verified by the actual sampling waveform, which has the advantages of high-speed operation, intelligent control, high technical performance and reliable operation

Development of Ling-zhi industry in China – emanated from the artificial cultivation in the Institute of Microbiology, Chinese Academy of Sciences (IMCAS)

Ling-zhi is a medicinal herb that generally refers to a fungus in the genus Ganoderma. It has been used as a medicinal mushroom in traditional Chinese medicine for more than 2000 years. Mycologists at the Institute of Microbiology, Chinese Academy of Sciences (IMCAS) first artificially cultivated the Ling-zhi fruiting body in the late 1960s (X.J. Liu’s team). In IMCAS, different research teams have extensively studied Ling-zhi in the aspects of national resource surveys, systematic taxonomy, chemical analysis, and processing for medicinal and health applications. The research results from IMCAS have provided essential support and prompted the development of the Ling-zhi industry in China to some extent. This review aims to summarize the history of research on Ling-zhi in IMCAS and its role in the development of the Ling-zhi economy

Degradation modeling and experiment of electro-hydraulic shift valve in contamination circumstances

In this article, a degradation assessment model has been proposed for electro-hydraulic shift valve in power-shift steering transmission. Our work is motivated by the failure mechanism of abrasive wear with a mathematic model. Abrasive wear will consecutively enlarge the clearance between the friction pairs. It is an overwhelming wear mechanism in the degradation of shift valve within serious contaminated fluid. Herein, a mathematic model is proposed by considering particle morphology and abrasion theory. Such model has been verified for its applicability and accuracy through comparison between the theoretical and experimental results

Neutrophil-Initiated Myocardial Inflammation and Its Modulation by B-Type Natriuretic Peptide: A Potential Therapeutic Target

Activation of neutrophils is a critically important component of the innate immune response to bacterial and chemical stimuli, and culminates in the &ldquo;neutrophil burst&rdquo;, which facilitates neutrophil phagocytosis via the release of superoxide anion radical (O2&minus;) from NADPH oxidase. Excessive and/or prolonged neutrophil activation results in substantial tissue injury and increases in vascular permeability&mdash;resulting in sustained tissue infiltration with neutrophils and monocytes, and persistent vasomotor dysfunction. Cardiovascular examples of such changes include acute and chronic systolic and diastolic heart failure (&ldquo;heart failure with preserved ejection fraction&rdquo;), and the catecholamine-induced inflammatory disorder takotsubo syndrome. We have recently demonstrated that B-type natriuretic peptide (BNP), acting via inhibition of activation of neutrophil NADPH oxidase, is an important negative modulator of the &ldquo;neutrophil burst&rdquo;, though its effectiveness in limiting tissue injury is partially lost in acute heart failure. The potential therapeutic implications of these findings, regarding the development of new means of treating both acute and chronic cardiac injury states, are discussed

Functional Evolution of <i>Pseudofabraea citricarpa</i> as an Adaptation to Temperature Change

Citrus target spot, caused by Pseudofabraea citricarpa, was formerly considered a cold-tolerant fungal disease. However, it has now spread from high-latitude regions to warmer low-latitude regions. Here, we conducted physiological observations on two different strains of the fungus collected from distinct regions, and evaluated their pathogenicity. Interestingly, the CQWZ collected from a low-latitude orchard, exhibited higher temperature tolerance and pathogenicity when compared to the SXCG collected from a high-latitude orchard. To further understand the evolution of temperature tolerance and virulence in these pathogens during the spread process, as well as the mechanisms underlying these differences, we performed genomic comparative analysis. The genome size of CQWZ was determined to be 44,004,669 bp, while the genome size of SXCG was determined to be 45,377,339 bp. Through genomic collinearity analysis, we identified two breakpoints and rearrangements during the evolutionary process of these two strains. Moreover, gene annotation results revealed that the CQWZ possessed 376 annotated genes in the “Xenobiotics biodegradation and metabolism” pathway, which is 79 genes more than the SXCG. The main factor contributing to this difference was the presence of salicylate hydroxylase. We also observed variations in the oxidative stress pathways and core pathogenic genes. The CQWZ exhibited the presence of a heat shock protein (HSP SSB), a catalase (CAT2), and 13 core pathogenic genes, including a LysM effector, in comparison to the SXCG. Furthermore, there were significant disparities in the gene clusters responsible for the production of seven metabolites, such as Fumonisin and Brefeldin. Finally, we identified the regulatory relationship, with the HOG pathway at its core, that potentially contributes to the differences in thermotolerance and virulence. As the global climate continues to warm, crop pathogens are increasingly expanding to new territories. Our findings will enhance understanding of the evolution mechanisms of pathogens under climate change

Parametric Simulations on Leakage and Performance of a Miniature Free-Piston Generator (MFPG)

The miniaturization of electrical equipment and popularization of portable devices is an appealing motivation for the development of small-scale heat engines. However, the in-cylinder charge leaks severely as the engine dimension shrinks. The free-piston engine on a small scale provides better sealing than other miniature heat engines. Therefore, a miniature free-piston generator (MFPG) with a single-piston internal combustion engine (ICE) and a voice coil motor (VCM) was proposed in this work. A dynamic model with special attention on the heat transfer and leakage was established accordingly, upon which parametric studies of leakage and its effects on the performance of the MFPG system were performed. Four key parameters, including scavenging pressure, ignition position, combustion duration and piston mass, were considered in the model. The results showed that the mass leakage during the compression decreases with the rise of the motoring current. The indicated thermal efficiency can be improved by boosting scavenging pressure and increase motoring current. The critical ignition position is 2 mm before the top dead center. When ignition occurs later than that, the MFPG system is incapable of outputting power. The chemical to electric energy conversion efficiency is about 5.13%, with an output power of 10~13 W and power density around 4.7~5.7 W/cc

Estimation of Pb and Cd Content in Soil Using Sentinel-2A Multispectral Images Based on Ensemble Learning

With the increasing economic growth in developing nations, soil heavy metal pollution has become a growing concern. Monitoring the heavy metal concentration in soil through remote sensing is crucial for safeguarding the ecological environment. However, the current indoor spectral measurement method has limitations, such as the discrete soil sampling space and weak spectral characteristics of soil heavy metals, leading to a poor robustness of remote sensing inversion models. This study presents a novel approach to address these challenges by incorporating a spatial feature of pollution sources and sinks to evaluate the spatial factors affecting pollutant diffusion and concentration. An integrated learning model, combining spatial and spectral information, is developed to estimate heavy metal content in soil using Sentinel-2A satellite data. A total of 235 soil samples were collected in Jiyuan, China, and the effective spectral transformation characteristics of Sentinel-2A data were screened. The impact of spectral characteristics, topographic characteristics, and spatial characteristics on retrieving soil heavy metal lead (Pb) and cadmium (Cd) content were analyzed. The optimal inversion method was determined through various integrated learning models, and the spatial distribution of heavy metals Pb and Cd was mapped. The results indicate that the accuracy of the inversion model was significantly improved by incorporating terrain features and spatial features of pollution sources. The Blending integrated learning method showed a 65.9% and 73.2% reduction in the RMSE of Pb and Cd, respectively, compared to other regression models. With R2 values of 0.9486 and 0.9489 for Pb and Cd, respectively, and a MAPE less than 0.2, the Blending model demonstrated high prediction accuracy