bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPARATIVE EFFICACY OF SYNTHETIC INSECTICIDES AGAINST CITRUS PSYLLA, DIAPHORINA CITRI KUWAYAMA (HOMOPTERA: PSYLLIDAE) UNDER LABORATORY AND FIELD CONDITIONS
Authors: Iqbal Mubashar , Ahmad Shahbaz , Gogi Muhammad , Atta Bilal , Nisar Muhammad Junaid
Published: August 2022

Citrus fruits are rich in macronutrients, such as simple sugars and nutritional fiber, and provide many kinds of micronutrients containing thiamine, vitamin B6, riboflavin, pantothenic acid, potassium, calcium, phosphorus, magnesium, and copper, which are vital for keeping health and normal growth. Production of citrus was strongly affected by citrus psylla (Diaphorina citri). The present study was carried out to determine the effectiveness of some synthetic insecticides with different concentrations against citrus psylla under field and laboratory conditions. Four insecticides viz. Politrin-C® (Profenofos + Cypermethrin), Talstar® (Bifenthrin), Confidor® (Imidacloprid), and Cymbush® (Cypermethrin) were used for evaluation of their effectiveness against citrus psylla. For laboratory experimentation, four concentrations of each insecticide along with one control treatment were made. For the field experiment, all the said insecticides were applied at field recommended doses. Citrus psylla was collected from an infested field of citrus crop and transferred in a plastic cage (60×60×60 cm) and kept in the IPM laboratory under standard laboratory conditions in the Department of Entomology, University of Agriculture Faisalabad Pakistan. Fresh leaves of citrus were used for the insect rearing as a diet for the insects. The rearing conditions were maintained at 25±2oC and 60-70% RH. Results revealed that LC50 values were 3.23%, 5.60%, 5.42% and 3.09% after 6 hours, 0.41%, 1.41%, 2.42% and 1.90% after 12 hours and 0.08%, 0.09%, 0.49% and 1.80% for Politrin-C®, Talstar®, Confidor® and Imazone® after 24 hours respectively. Politrin-C® was found to be more effective because of causing maximum mortality (71.15%), (51.20%), and (34.64%) after 24 hours, 12 hours, and 6 hours respectively of post-treatment application. The maximum population reduction of 66.68% was recorded with Politrin-C® followed by 62.96%, 61.23%, and 59.68% population reductions observed with treatments with Confidor®, Imazone®, and Talstar® respectively. However, Politrin-C® proved to be more toxic and considered effective for D. citri.
SOME NEW RECORDS OF HELICOTYLENCHUS (STEINER, 1945) SPECIES FROM PAKISTAN (NEMATODA: HOPLOLAIMIDAE)
Authors: Ishaque Uzma , Kazi Nasira
Published: August 2022

The detailed morphological and taxonomical studies revealed the presence of number of plant parasitic nematodes from grass (Cynodon dactylon L.) at different areas of University of Karachi. The genus Helicotylenchus was encountered with highest occurrence among other plant parasitic genera. In the present investigations, two known spiral nematode species viz. Helicotylenchus abuharazi Zeidan and Geraert, 1990 and Helicotylenchus wajihi Sultan, 1981 associated with grass were found as new records and were studied for their taxonomic descriptions. Brief redescription along with their measurements and illustrations are provided herein. These species were reported for the first time from Pakistan.
Säker digitalisering för lantbruket
Authors: Lohm Estelle , Andersson Niklas
Published: August 2022

Rapportens syfte är att kartlägga digitaliseringen av lantbruket genom att se på vilken teknik som används idag, och som kommer imorgon. Med detta undersöktes även de uppfattade riskerna som medföljer utvecklingen. Rapporten har använt semistrukturerade intervjuer för att samla in kunskap och åsikter från personer med olika roller i lantbruksbranschen. Även en litteraturundersökning har genomförts för att ge en bredare bild. Resultatet visar på att digitaliseringen har skett och sker i olika grad från gård till gård och varierar från väldigt digitaliserade gårdar till de gårdar som inte har digitaliserats alls. Resultatet visade på vilken digitalteknik som vanligen används på gårdar, exempelvis GPS och N-sensor, och vilka hinder som anses finnas för att hela branschen ska digitaliseras. Exempel på det är stora initiala investeringar och inte tillräcklig teknikkunskap hos lantbrukarna. De säkerhetsrisker och hot som kunde identifieras var exempelvis störningar i internet, buggar i mjukvara och avsiktliga attacker mot uppkopplade enheter. Rapporten är avgränsad till jordbruket och berör inte skogsbruket. Huvudfokus var på det svenska jordbruket men även internationella aspekter togs hänsyn till när intervjudeltagare nämnde det och i litteraturgenomgången.
The application of CRISPR /Cas mediated gene editing in synthetic biology: Challenges and optimizations
Authors: Li Wenqian , Huang Can , Chen Jingyu
Published: August 2022

Clustered regularly interspaced short palindromic repeats (CRISPR) and its associated enzymes (Cas) is a simple and convenient genome editing tool that has been used in various cell factories and emerging synthetic biology in the recent past. However, several problems, including off-target effects, cytotoxicity, and low efficiency of multi-gene editing, are associated with the CRISPR/Cas system, which have limited its application in new species. In this review, we briefly describe the mechanisms of CRISPR/Cas engineering and propose strategies to optimize the system based on its defects, including, but not limited to, enhancing targeted specificity, reducing toxicity related to Cas protein, and improving multi-point editing efficiency. In addition, some examples of improvements in synthetic biology are also highlighted. Finally, future perspectives of system optimization are discussed, providing a reference for developing safe genome-editing tools for new species.
Vacancy defect-promoted nanomaterials for efficient phototherapy and phototherapy-based multimodal Synergistic Therapy
Authors: Xiong Xinyu , Wang Li , He Shan , Guan Shanyue , Li Dawei , Zhang Mingming , Qu Xiaozhong
Published: August 2022

Phototherapy and multimodal synergistic phototherapy (including synergistic photothermal and photodynamic therapy as well as combined phototherapy and other therapies) are promising to achieve accurate diagnosis and efficient treatment for tumor, providing a novel opportunity to overcome cancer. Notably, various nanomaterials have made significant contributions to phototherapy through both improving therapeutic efficiency and reducing side effects. The most key factor affecting the performance of phototherapeutic nanomaterials is their microstructure which in principle determines their physicochemical properties and the resulting phototherapeutic efficiency. Vacancy defects ubiquitously existing in phototherapeutic nanomaterials have a great influence on their microstructure, and constructing and regulating vacancy defect in phototherapeutic nanomaterials is an essential and effective strategy for modulating their microstructure and improving their phototherapeutic efficacy. Thus, this inspires growing research interest in vacancy engineering strategies and vacancy-engineered nanomaterials for phototherapy. In this review, we summarize the understanding, construction, and application of vacancy defects in phototherapeutic nanomaterials. Starting from the perspective of defect chemistry and engineering, we also review the types, structural features, and properties of vacancy defects in phototherapeutic nanomaterials. Finally, we focus on the representative vacancy defective nanomaterials recently developed through vacancy engineering for phototherapy, and discuss the significant influence and role of vacancy defects on phototherapy and multimodal synergistic phototherapy. Therefore, we sincerely hope that this review can provide a profound understanding and inspiration for the design of advanced phototherapeutic nanomaterials, and significantly promote the development of the efficient therapies against tumor.
Highly efficient production of rebaudioside D enabled by structure-guided engineering of bacterial glycosyltransferase YojK
Authors: Guo Baodang , Hou Xiaodong , Zhang Yan , Deng Zhiwei , Ping Qian , Fu Kai , Yuan Zhenbo , Rao Yijian
Published: August 2022

Owing to zero-calorie, high-intensity sweetness and good taste profile, the plant-derived sweetener rebaudioside D (Reb D) has attracted great interest to replace sugars. However, low content of Reb D in stevia rebaudiana Bertoni as well as low soluble expression and enzymatic activity of plant-derived glycosyltransferase in Reb D preparation restrict its commercial usage. To address these problems, a novel glycosyltransferase YojK from Bacillus subtilis 168 with the ability to glycosylate Reb A to produce Reb D was identified. Then, structure-guided engineering was performed after solving its crystal structure. A variant YojK-I241T/G327N with 7.35-fold increase of the catalytic activity was obtained, which allowed to produce Reb D on a scale preparation with a great yield of 91.29%. Moreover, based on the results from molecular docking and molecular dynamics simulations, the improvement of enzymatic activity of YojK-I241T/G327N was ascribed to the formation of new hydrogen bonds between the enzyme and substrate or uridine diphosphate glucose. Therefore, this study provides an engineered bacterial glycosyltransferase YojK-I241T/G327N with high solubility and catalytic efficiency for potential industrial scale-production of Reb D.
Numerically disturbed shake table experimentation to examine nonlinear signal-based control
Authors: Enokida Ryuta , Ikago Kohju , Kajiwara Koichi
Published: August 2022

This study introduces a numerically disturbed experimentation to address the shake table control degradation commonly observed in shake table experiments. This degradation is caused by nonlinear characteristics, such as seismic damage, in the experiments; however, observing such nonlinear characteristics is a major purpose of these experiments. In the proposed numerically disturbed experimentation, a structure is numerically simulated, and its structural responses are fed back as the disturbance signal to the table in the physical domain via real-time interaction. This enables us to examine the control performance of a shake table with a structure, without having to place an actual structure on it. This experimentation is beneficial in cases wherein new control methods are applied for shake table control because the control performance can be examined safely and efficiently under various structural conditions by using numerical simulations. The proposed experimentation was applied to the shake table control examination of nonlinear signal-based control (NSBC), which has a nonlinear signal feedback action for nonlinear structural dynamics, as well as inversion-based control (IBC), which is a common feedforward method. In the numerically disturbed experiments, NSBC accurately realized a seismic acceleration record on the shake table with severe nonlinear characteristics, whereas IBC exhibited control degradation due to nonlinear characteristics. Similar results were obtained using actual shake table experiments with a steel structure. Therefore, the proposed numerically disturbed experimentation can be an alternative to shake table experiments using structures.
PLK1-mediated phosphorylation of PPIL2 regulates HR via CtIP
Authors: Qiu Zhiyu , Hao Shuailin , Song Shikai , Zhang Ruiling , Yan Tingyu , Lu Zhifang , Wang Hailong , Jia Zongchao , Zheng Jimin
Published: August 2022

Homologous recombination (HR) is an error-free DNA double-strand break (DSB) repair pathway, which safeguards genome integrity and cell viability. Human C-terminal binding protein (CtBP)—interacting protein (CtIP) is a central regulator of the pathway which initiates the DNA end resection in HR. Ubiquitination modification of CtIP is known in some cases to control DNA resection and promote HR. However, it remains unclear how cells restrain CtIP activity in unstressed cells. We show that the ubiquitin E3 ligase PPIL2 is recruited to DNA damage sites through interactions with an HR-related protein ZNF830, implying PPIL2’s involvement in DNA repair. We found that PPIL2 interacts with and ubiquitinates CtIP at the K426 site, representing a hereunto unknown ubiquitination site. Ubiquitination of CtIP by PPIL2 suppresses HR and DNA resection. This inhibition of PPIL2 is also modulated by phosphorylation at multiple sites by PLK1, which reduces PPIL2 ubiquitination of CtIP. Our findings reveal new regulatory complexity in CtIP ubiquitination in DSB repair. We propose that the PPIL2-dependent CtIP ubiquitination prevents CtIP from interacting with DNA, thereby inhibiting HR.
An evolutionary and physiological perspective on cell-substrate adhesion machinery for cell migration
Authors: Fierro Morales Julio C. , Xue Qian , Roh-Johnson Minna
Published: August 2022

Cell-substrate adhesion is a critical aspect of many forms of cell migration. Cell adhesion to an extracellular matrix (ECM) generates traction forces necessary for efficient migration. One of the most well-studied structures cells use to adhere to the ECM is focal adhesions, which are composed of a multilayered protein complex physically linking the ECM to the intracellular actin cytoskeleton. Much of our understanding of focal adhesions, however, is primarily derived fromin vitrostudies in Metazoan systems. Though these studies provide a valuable foundation to the cell-substrate adhesion field, the evolution of cell-substrate adhesion machinery across evolutionary space and the role of focal adhesionsin vivoare largely understudied within the field. Furthering investigation in these areas is necessary to bolster our understanding of the role cell-substrate adhesion machinery across Eukaryotes plays during cell migration in physiological contexts such as cancer and pathogenesis. In this review, we review studies of cell-substrate adhesion machinery in organisms evolutionary distant from Metazoa and cover the current understanding and ongoing work on how focal adhesions function in single and collective cell migration in anin vivoenvironment, with an emphasis on work that directly visualizes cell-substrate adhesions. Finally, we discuss nuances that ought to be considered moving forward and the importance of future investigation in these emerging fields for application in other fields pertinent to adhesion-based processes.
Constructing atomically-dispersed Mn on ZIF-derived nitrogen-doped carbon for boosting oxygen reduction
Authors: Deng Yaoyao , Pang Jiazheng , Ge Wenzheng , Zhang Minxi , Zhang Wentao , Zhang Wei , Xiang Mei , Zhou Quanfa , Bai Jirong
Published: August 2022

Exploring durable and highly-active non-noble-metal nanomaterials to supersede Pt-based nanomaterials is an effective way, which can reduce the cost and boost the catalytic efficiency of oxygen reduction reaction (ORR). Herein, we constructed atomically-dispersed Mn atoms on the ZIF-derived nitrogen-doped carbon frameworks (Mn-Nx/NC) by stepwise pyrolysis. The Mn-Nx/NC relative to pure nitrogen-doped carbon (NC) exhibited superior electrocatalytic activity with a higher half-wave potential (E1/2 = 0.88 V) and a modest Tafel slope (90 mV dec−1) toward ORR. The enhanced ORR performance of Mn-Nx/NC may be attributed to the existence of Mn-Nx active sites, which can more easily adsorb intermediates, promoting the efficiency of ORR. This work provides a facile route to synthesize single-atom catalysts for ORR.
Improving classification results on a small medical dataset using a GAN; An outlook for dealing with rare disease datasets
Authors: Röglin Julia , Ziegeler Katharina , Kube Jana , König Franziska , Hermann Kay-Geert , Ortmann Steffen
Published: August 2022

For clinical decision support systems, automated classification algorithms on medical image data have become more important in the past. For such computer vision problems, deep convolutional neural networks (DCNNs) have made breakthroughs. These often require large, annotated, and privacy-cleared datasets as a prerequisite for gaining high-quality results. This proves to be difficult with rare diseases due to limited incidences. Therefore, it is hard to sensitize clinical decision support systems to identify these diseases at an early stage. It has been shown several times, that synthetic data can improve the results of clinical decision support systems. At the same time, the greatest problem for the generation of these synthetic images is the data basis. In this paper, we present four different methods to generate synthetic data from a small dataset. The images are from 2D magnetic resonance tomography of the spine. The annotation resulted in 540 healthy, 47 conspicuously non-pathological, and 106 conspicuously pathological vertebrae. Four methods are presented to obtain optimal generation results in each of these classes. The obtained generation results are then evaluated with a classification net. With this procedure, we showed that adding synthetic annotated data has a positive impact on the classification results of the original data. In addition, one of our methods is appropriate to generate synthetic image data from <50 images. Thus, we found a general approach for dealing with small datasets in rare diseases, which can be used to build sensitized clinical decision support systems to detect and treat these diseases at an early stage.
Human factors affecting ventilation in Australian classrooms during the COVID-19 pandemic: Toward insourcing occupants' proficiency in ventilation management
Authors: Snow Stephen , Danam Royce , Leardini Paola , Glencross Mashhuda , Beeson Brett , Ottenhaus Lisa-Mareike , Boden Marie
Published: August 2022

Underventilation in classrooms is associated with poorer academic performance and greater transmission risk of COVID-19. In a study involving data from CO2 logging in 67 classrooms in Brisbane, Australia, it was found that more than half of the classrooms monitored experienced between 5 and 50 separate instances of CO2 concentrations exceeding 1,800 ppm, a level at which cognitive performance reductions have been recorded and which is considered high risk for COVID-19 transmission. The research identifies a number of human-related factors affecting ventilation in certain classrooms, including the disabling of window operation to minimize the potential for student interference, keeping windows closed in naturally ventilated buildings to improve energy efficiency, difficult to reach switches for exhaust fans and perceptions of the likelihood of remedial action being taken. Identifying Inbodied Interaction as a useful lens to enable users themselves to better identify and remedy instances of poor IAQ, the paper contributes: (1) Insight into the CO2 concentrations experienced in Australian classrooms during the COVID pandemic; (2) Identification of human-factors contributing to the ventilation—and underventilation—of the rooms monitored; and (3) Suggestions for how to foster greater awareness of ventilation among classroom occupants and translate awareness into more active, informed, and healthier ventilation behaviors from occupants, using principles of Inbodied Interaction.
Reliability and validity of sit-to-stand test protocols in patients with coronary artery disease
Authors: Wang Zheng , Yan Jianhua , Meng Shu , Li Jiajia , Yu Yi , Zhang Tingting , Tsang Raymond C. C. , El-Ansary Doa , Han Jia , Jones Alice Y. M.
Published: August 2022

Background

Sit-To-Stand (STS) tests are reported as feasible alternatives for the assessment of functional fitness but the reliability of these tests in people with coronary artery disease (CAD) has not been reported. This study explored the test-retest reliability, convergent and known-groups validity of the five times, 30-sec and 1-min sit-to-stand test (FTSTS test, 30-s STS test and 1-min STS test respectively) in patients with CAD. The feasibility of applying these tests to distinguish the level of risk for cardiovascular events in CAD patients was also investigated.

Methods

Patients with stable CAD performed a 6MWT and 3 STS tests in random order on the same day. Receiver operating characteristic (ROC) curve analyses were conducted using STS test data to differentiate patients with low or high risk of cardiovascular events based on the risk level determined by distance covered in the 6MWT as > or ≤ 419 m. Thirty patients repeated the 3 STS tests on the following day.

Results

112 subjects with diagnoses of atherosclerosis or post-percutaneous coronary intervention, or post-acute myocardial infarction (post-AMI) participated in the validity analysis. All 3 STS tests demonstrated moderate and significant correlation with the 6MWT (coefficient values r for the FTSTS, 30-s STS and 1-min STS tests were−0.53, 0.57 and 0.55 respectively). Correlations between left ventricular ejection fraction (LVEF) and all STS tests and between 6MWT and LVEF were only weak (r values ranged from 0.27 to 0.31). Subgroup analysis showed participants in the post-AMI group performed worse in all tests compared to non-myocardial infarction (non-MI) group. The area under the curve (AUC) was 0.80 for FTSTS (sensitivity: 75.0%, specificity: 73.8%, optimal cut-off: >11.7 sec), and the AUC, sensitivity, specificity and optimal cut-off for 30-s STS and 1-min STS test were 0.83, 75.0%, 76.2%, ≤ 12 repetitions and 0.80, 71.4%, 73.8%, ≤ 23 repetitions respectively. The intraclass correlation coefficients (ICC) for repeated measurements of the FTSTS, 30-s STS and 1-min STS tests were 0.96, 0.95 and 0.96 respectively, with the minimal detectable change (MDC95) computed to be 1.1 sec 1.8 repetitions and 3.9 repetitions respectively.

Conclusions

All STS tests demonstrated good test-retest reliability, convergent and known-groups validity. STS tests may discriminate low from high levels of risk for a cardiovascular event in patients with CAD.
Osteoarthritis, coronary artery disease, and myocardial infarction: A mendelian randomization study
Authors: Xu Huiqing , Ling Yuxiao , Jiang Han , Li Yingjun , Jiang Minmin
Published: August 2022

Background

Observational studies indicate that osteoarthritis (OA) and coronary artery disease (CAD), as well as myocardial infarction (MI), are often diagnosed as comorbid diseases. We performed a bidirectional Mendelian randomization (MR) study to demonstrate whether there is a causal relationship between OA, CAD, and MI.

Methods

We extracted single nucleotide polymorphisms (SNPs) related to OA in the Genetics of Osteoarthritis (GO) Consortium as instrumental variables to assess whether OA is associated with CAD and MI in the CARDIoGRAMplusC4D 1,000 Genomes genome-wide association study (GWAS). In the reverse MR, we used CAD-associated and MI-associated SNPs to the GWAS of OA to analyze their causality. These GWASs included 766,690 individuals of OA, 184,305 individuals of CAD, and 166,065 individuals of MI. MR was conducted using several methods, including the inverse variance weighted (IVW) method, the weighted median method, the MR-Egger method, and the MR-Pleiotropy RESidual Sum and Outlier (MR-PRESSO) method.

Results

The forward causal effect of OA on CAD and MI was not observed. In reverse analysis, no causal effect was discovered for CAD on the risk of OA. Notably, we observed a causal association between MI and total OA [IVW odds ratio (OR) = 0.95, 95% CI = 0.93, 0.98, P = 4E−04] and spine OA (IVW OR = 0.92, 95% CI = 0.88, 0.97, P = 0.001) but a null association between MI and knee OA, hip OA, hand OA, and thumb OA.

Conclusion

This MR study identifies a potentially protective effect of genetically predicted MI on total and spine OA risks.
m6A regulator-mediated RNA methylation modification patterns are involved in immune microenvironment regulation of coronary heart disease
Authors: Li Zhaoshui , Song Yanjie , Wang Meng , Shen Ruxin , Qin Kun , Zhang Yu , Jiang Ting , Chi Yifan
Published: August 2022

Background

Although the roles of m6A modification in the immune responses to human diseases have been increasingly revealed, their roles in immune microenvironment regulation in coronary heart disease (CHD) are poorly understood.

Methods

The GSE20680 and GSE20681 datasets related to CHD were acquired from the Gene Expression Omnibus (GEO) database. A total of 30 m6A regulators were used to perform LASSO regression to identify the significant genes involved in CHD. Unsupervised clustering analysis was conducted using the m6A regulators to distinguish the m6A RNA methylation patterns in patients with CHD. The differentially expressed genes (DEGs) and biological characteristics, including GO and KEGG enrichment results, were assessed for the different m6A patterns to analyse the impacts of m6A regulators on CHD. Hub genes were identified, and subsequent microRNAs-mRNAs (miRNAs–mRNAs) and mRNAs-transcriptional factors (mRNA-TFs) interaction networks were constructed by the protein and protein interaction (PPI) network method using Cytoscape software. The infiltrating proportion of immune cells was assessed by ssGSEA and the CIBERSORT algorithm. Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of the significant m6A regulators and hub genes.

Results

Four of 30 m6A regulators (HNRNPC, YTHDC2, YTHDF3, and ZC3H13) were identified to be significant in the development of CHD. Two m6A RNA methylation clusters were distinguished by unsupervised clustering analysis based on the expression of the 30 m6A regulators. A total of 491 genes were identified as DEGs between the two clusters. A PPI network including 308 mRNAs corresponding to proteins was constructed, and 30 genes were identified as hub genes that were enriched in the bioprocesses of peptide cross-linking, keratinocyte differentiation. Twenty-seven hub genes were found to be related to miRNAs, and seven hub genes were found to be related to TFs. Moreover, among the 30 hub genes, eight genes were found to be upregulated in CHD, and three were found to be downregulated in CHD compared to the normal people. The high m6A modification pattern was associated with a higher infiltrated abundance of immune cells.

Conclusion

Our findings demonstrated that m6A modification plays crucial roles in the diversity and complexity of the immune microenvironment in CHD.
Revascularization of chronic total occlusion coronary artery and cardiac regeneration
Authors: Liao Ruoxi , Li Zhihong , Wang Qiancheng , Lin Hairuo , Sun Huijun
Published: August 2022

Coronary chronic total occlusion (CTO) contributes to the progression of heart failure in patients with ischemic cardiomyopathy. Randomized controlled trials demonstrated that percutaneous coronary intervention (PCI) for CTO significantly improves angina symptoms and quality of life but fails to reduce clinical events compared with optimal medical therapy. Even so, intervening physicians strongly support CTO-PCI. Cardiac regeneration therapy after CTO-PCI should be a promising approach to improving the prognosis of ischemic cardiomyopathy. However, the relationship between CTO revascularization and cardiac regeneration has rarely been studied, and experimental studies on cardiac regeneration usually employ rodent models with permanent ligation of the coronary artery rather than reopening of the occlusive artery. Limited early-stage clinical trials demonstrated that cell therapy for cardiac regeneration in ischemic cardiomyopathy reduces scar size, reverses cardiac remodeling, and promotes angiogenesis. This review focuses on the status quo of CTO-PCI in ischemic cardiomyopathy and the clinical prospect of cardiac regeneration in this setting.
Glyoxylase-1 combats dicarbonyl stress and right ventricular dysfunction in rodent pulmonary arterial hypertension
Authors: Prisco Sasha Z. , Hartweck Lynn , Keen Jennifer L. , Vogel Neal , Kazmirczak Felipe , Eklund Megan , Hemnes Anna R. , Brittain Evan L. , Prins Kurt W.
Published: August 2022

Background

Heightened glycolytic flux is associated with right ventricular (RV) dysfunction in pulmonary arterial hypertension (PAH). Methylglyoxal, a glycolysis byproduct, is a highly reactive dicarbonyl that has toxic effects via non-enzymatic post-translational modifications (protein glycation). Methylglyoxal is degraded by the glyoxylase system, which includes the rate-limiting enzyme glyoxylase-1 (GLO1), to combat dicarbonyl stress. However, the potential consequences of excess protein glycation on RV function are unknown.

Methods

Bioinformatics analysis of previously identified glycated proteins predicted how protein glycation regulated cardiac biology. Methylglyoxal treatment of H9c2 cardiomyocytes evaluated the consequences of excess protein glycation on mitochondrial respiration. The effects of adeno-associated virus serotype 9-mediated (AAV9) GLO1 expression on RV function in monocrotaline rats were quantified with echocardiography and hemodynamic studies. Immunoblots and immunofluorescence were implemented to probe the effects of AAV-Glo1 on total protein glycation and fatty acid oxidation (FAO) and fatty acid binding protein levels.

Results

In silico analyses highlighted multiple mitochondrial metabolic pathways may be affected by protein glycation. Exogenous methylglyoxal minimally altered mitochondrial respiration when cells metabolized glucose, however methylglyoxal depressed FAO. AAV9-Glo1 increased RV cardiomyocyte GLO1 expression, reduced total protein glycation, partially restored mitochondrial density, and decreased lipid accumulation. In addition, AAV9-Glo1 increased RV levels of FABP4, a fatty acid binding protein, and hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunits alpha and beta (HADHA and HADHB), the two subunits of the mitochondrial trifunctional protein for FAO. Finally, AAV9-Glo1 blunted RV fibrosis and improved RV systolic and diastolic function.

Conclusion

Excess protein glycation promotes RV dysfunction in preclinical PAH, potentially through suppression of FAO.
Diagnostic value of cardiac miR-126-5p, miR-134-5p, and miR-499a-5p in coronary artery disease-induced sudden cardiac death
Authors: Li Linfeng , He Xiangwang , Liu Min , Yun Libing , Cong Bin
Published: August 2022

Background

The identification of coronary artery disease-induced sudden cardiac death (CAD-SCD) has always been a medical challenge. MicroRNAs (miRNAs) played vital roles in pathogenesis processes and served as potential biomarkers for cardiovascular and many other diseases. The aim of this study was to investigate the diagnostic value of the specific miRNAs for CAD-SCD.

Methods

A total of 30 autopsy-verified CAD-SCD victims were selected, including 18 individuals who experienced more than once asymptomatic myocardial ischemia (CAD-activated SCD) and 12 victims without prominent pathological features of insufficient blood supply (CAD-silent SCD). Meanwhile, 30 traumatic victims were enrolled as controls. Systematic postmortem examinations were performed in all study population. The expressions of cardiac miR-126-5p, miR-134-5p, and miR-499a-5p were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR).

Results

RT-qPCR showed significant downregulations of miR-126-5p and miR-499a-5p in CAD-SCD victims, with no obvious difference in miR-134-5p. Receiver-operating characteristic analysis revealed the diagnostic performance of miR-126-5p (areas under the curve [AUC] = 0.76) and validated miR-499a-5p (AUC = 0.82) as a sensitive marker. Additionally, the decreased expression of the two specific cardio-miRNAs was detected for discriminating CAD-silent SCD and CAD-activated SCD. Compared with the limited diagnostic value of single miR-126-5p and miR-499a-5p, their combination could achieve better discriminative capacity (AUC = 0.82, sensitivity = 91.7%, specificity = 77.8%).

Conclusion

Cardiac miR-126-5p and miR-499a-5p presented good diagnostic abilities for CAD-SCD, and their combination could help evaluate CAD condition. These targeted miRNAs as novel biomarkers are expected to be useful to discriminate the detailed causes in real SCD cases.
Hypertension and human immunodeficiency virus: A paradigm for epithelial sodium channels?
Authors: Mutengo Katongo H. , Masenga Sepiso K. , Mwesigwa Naome , Patel Kaushik P. , Kirabo Annet
Published: August 2022

Hypertension is a risk factor for end organ damage and death and is more common in persons with HIV compared to the general population. Several mechanisms have been studied in the pathogenesis of hypertension. Current evidence suggests that the epithelial sodium channel (ENaC) plays a key role in regulating blood pressure through the transport of sodium and water across membranes in the kidney tubules, resulting in retention of sodium and water and an altered fluid balance. However, there is scarcity of information that elucidates the role of ENaC in HIV as it relates to increasing the risk for development or pathogenesis of hypertension. This review summarized the evidence to date implicating a potential role for altered ENaC activity in contributing to hypertension in patients with HIV.
Active Tracking-based cardiac triggering for MR-thermometry during radiofrequency ablation therapy in the left ventricle
Authors: Mooiweer Ronald , Schneider Rainer , Krafft Axel Joachim , Empanger Katy , Stroup Jason , Neofytou Alexander Paul , Mukherjee Rahul K. , Williams Steven E. , Lloyd Tom , O'Neill Mark , Razavi Reza , Schaeffter Tobias , Neji Radhouene , Roujol Sébastien
Published: August 2022

Cardiac MR thermometry shows promise for real-time guidance of radiofrequency ablation of cardiac arrhythmias. This technique uses ECG triggering, which can be unreliable in this situation. A prospective cardiac triggering method was developed for MR thermometry using the active tracking (AT) signal measured from catheter microcoils. In the proposed AT-based cardiac triggering (AT-trig) sequence, AT modules were repeatedly acquired to measure the catheter motion until a cardiac trigger was identified to start cardiac MR thermometry using single-shot echo-planar imaging. The AT signal was bandpass filtered to extract the motion induced by the beating heart, and cardiac triggers were defined as the extremum (peak or valley) of the filtered AT signal. AT-trig was evaluated in a beating heart phantom and in vivo in the left ventricle of a swine during temperature stability experiments (6 locations) and during one ablation. Stability was defined as the standard deviation over time. In the phantom, AT-trig enabled triggering of MR thermometry and resulted in higher temperature stability than an untriggered sequence. In all in vivo experiments, AT-trig intervals matched ECG-derived RR intervals. Mis-triggers were observed in 1/12 AT-trig stability experiments. Comparable stability of MR thermometry was achieved using peak AT-trig (1.0 ± 0.4°C), valley AT-trig (1.1 ± 0.5°C), and ECG triggering (0.9 ± 0.4°C). These experiments show that continuously acquired AT signal for prospective cardiac triggering is feasible. MR thermometry with AT-trig leads to comparable temperature stability as with conventional ECG triggering. AT-trig could serve as an alternative cardiac triggering strategy in situations where ECG triggering is not effective.
Case report: Mexiletine suppresses ventricular arrhythmias in Andersen-Tawil syndrome
Authors: Yang Jing , Li Kun , Lv Tingting , Xie Ying , Liu Fang , Zhang Ping
Published: August 2022

It is arduous to determine clinical solutions for Andersen-Tawil syndrome (ATS) in patients intolerant of β-blocker. Here, we present the case of a 7-year-old boy with periodic paralysis and dysmorphic features who experienced syncope four times during exercise. His ECG revealed enlarged U waves and QU-prolongation associated with ATS-specific U wave patterns, frequent PVCs, and non-sustained bidirectional or polymorphic ventricular tachycardia. The genetic test showed a de novo missense R218W mutation of KCNJ2. With the diagnosis of ATS and intolerance of β-blocker, the patient was prescribed oral medications of mexiletine 450 mg/day without severe adverse effects. The repeat ECG showed decreased PVC burden from 38 to 3% and absence of ventricular tachycardia. He remained symptom-free during over 2 years of outpatient follow-up. This case demonstrates a new anti-arrhythmic therapy with mexiletine for prevention of life-threatening cardiac events in patients with ATS who are intolerant of β-blocker treatment.
CD4+ T-lymphocytes exhibit biphasic kinetics post-myocardial infarction
Authors: Kumar Vinay , Prabhu Sumanth D. , Bansal Shyam S.
Published: August 2022

CD4+T-cells facilitate wound healing post-myocardial infarction (MI) but promote left-ventricular (LV) remodeling during ischemic heart failure (HF; 8 weeks post-MI). Therefore, it is critical to understand if sustained CD4+T-cell activation leads to this pathological response, or if phenotypically different T-cells are activated during MI vs. HF. Using flow cytometry, we found that cardiac CD4+T-cells exhibit two distinct patterns of transmigration. First pattern consisted of a rapid CD4+T-cell response with maximal levels seen at 3 days post-MI which return to baseline by 14 days. However, during HF we observed a 2nd phase of activation and CD4+T-cells were ∼20-fold higher in HF as compared to sham-operated mice. Importantly, these biphasic kinetics were observed with all major T-cell subsets such as Th1, Th2, Th17, and regulatory T-cells suggesting a global change. To determine the role of this 2nd peak of T-cell activation, CD4-iDTR mice were generated and treated with DT every 10 from 28 days post-MI to deplete CD4+T-cells during chronic HF. While littermate control mice showed increased end-systolic and end-diastolic volumes (ESV and EDV) and decreased ejection fraction (EF) from 4 to 8 weeks post-MI, depletion of CD4+T-cells in Cre + mice significantly blunted LV remodeling and inhibited progressive increases in the EDV and ESV, and reduction in EF. This suggests that CD4+T-cell responses occurring during HF are different than those occurring during MI and promote LV remodeling and progressive cardiac dysfunction. Temporal immunomodulation of CD4+T-cells could be a translatable modality for ischemic HF.
Petrogenesis of the late Cretaceous Budongla Mg-rich monzodiorite pluton in the central Lhasa subterrane, Tibet, China: Whole-rock geochemistry, zircon U-Pb dating, and zircon Lu-Hf isotopes
Authors: Liu Hong , Li You-Guo , Li Wen-Chang , Li Guang-Ming , Ma Dong-Fang , Ouyang Yuan , Huang Han-Xiao , Zhang Zhi-Lin , Li Tong , Wu Jun-Yi
Published: August 2022

Mg-rich monzodiorite are found in the Budongla gold ore district, Zhongba County, Xizang (Tibet) Autonomous Region, P.R. China. Studying the petrogenesis of this intermediate pluton can provide effective information to explore the geological evolution of the Lhasa terrane. One monzodiorite sample yielded a weighted mean 206Pb/238U age of 92.7 ± 1.1 Ma (mean square weighted deviation=0.33) using LA-ICP-MS zircon U-Pb dating, which represents the late phase of Late Cretaceous magmatism. The rock-forming minerals in the Budongla Mg-rich monzodiorite mainly include K-feldspar, plagioclase, quartz, biotite augite, and amphibole, and its accessory minerals mainly include magnetite, titanite, zircon, and apatite. The rocks are rich in K2O+Na2O and K2O with medium contents of SiO2, CaO, and A12O3,, suggesting these rocks belong to the high-K calc-alkaline series. These rocks have high MgO, Fe2O3, and FeO, with high Mg# values and low DI, which implies they are Mg-rich intermediate intrusive rocks. The rocks are enriched in LREEs and LILEs and depleted in HREEs and HFSEs. They have negative Eu anomalies, no obvious negative Ce anomalies, and slightly negative εHf(t). We infer that the Budongla pluton is a high-K calc-alkaline metaluminous Mg-rich monzodiorite and intruded during the post-collisional period of the Lhasa and Qiangtang terranes.
The Hapuku Rock Avalanche: Breaching and evolution of the landslide dam and outflow channel revealed using high spatiotemporal resolution datasets
Authors: Wolter Andrea , Gasston Caleb , Morgenstern Regine , Farr Jason , Rosser Brenda , Massey Chris , Townsend Dougal , Tunnicliffe Jon
Published: August 2022

Landslide dams have been recognised as significant components of multi-hazard cascading systems, linking slopes and rivers. Despite the potential for catastrophic consequences, landslide dam breaching and evolution remain under-researched and poorly understood, often due to the remoteness of large volume, valley-blocking landslides and the general lack of high resolution pre- and post-failure survey data. The Hapuku Rock Avalanche presents a unique opportunity to study landslide dam evolution and breaching timelines due to the accessibility of the site and the availability and resolution of pre- and post-failure remote sensing data. Field observations and mapping, sampling, geophysical surveying, and 27 remote sensing surveys from 2016 to 2022 have provided detailed data on the dam. The Hapuku landslide was the largest rock avalanche triggered by the 2016 Mw 7.8 Kaikōura earthquake sequence, occurring ∼9 km upstream of the main highway and rail corridor on the South Island of New Zealand. It dammed the Hapuku River, which rapidly formed a lake behind the 80 m-high deposit. Four major erosion events and three significant partial breach events, identified through observations and remote sensing data differencing, resulted in water outflow from the lake, significant erosion of the dam and deposition of sediment into the river. The partial breaches correspond with less than 1 in 10-year rainfall events in 2017 and 2018, and the first occurred 141 days after dam formation. Seepage and internal erosion of the dam were observed to be progressing upstream before the partial breaches, in which water overtopped the dam. The third partial breach event, 2 years after dam formation, was the most significant erosional event in the last 6 years. The dam has eroded episodically and more locally since 2018, and the degree of erosion appears to be decreasing with time, despite more intense storms. A small lake remains. The evolution of the Hapuku Rock Avalanche dam emphasises the complexity of dam and breaching evolution, which are often oversimplified.
The hydromechanical behavior of opalinus clay fractures: Combining roughness measurements with computer simulations
Authors: Keller Lukas M.
Published: August 2022

The role of surface roughness of fractures in Opalinus Clay and in rocks in general is relevant in understanding the hydromechanical behavior of fractures. Two different fracture surfaces of shear fractures in the Opalinus Clay were investigated. The fracture surfaces were characterized based on their roughness power spectrum. It was found that slickensides fracture surfaces are near fractal-like up to the longest scale with a fractal dimension Df ∼ 2.1 and in the absence of a roll-off region at long wavelengths. In contrast, the glassy fracture surfaces show a roll-off region, which is characteristic of a flat surface with rather small and local topographic height variations. The glassy fracture surface is near fractal like with Df ∼ 2.0. The measured roughness power spectra were used to create fracture models to study the behavior of different fracture closure mechanism: 1) increasing congruence (matedness), 2) closure by compression and 3) closure by swelling. It turned out that the relationship between permeability and mean aperture depends on the fracture closure mechanism. Concerning closure by compression, the root mean square (rms) value of the aperture (aper) distribution aperrms influences the contact formation behavior, which in turn controls the hydromechanical properties. The lower aperrms is, the lower the fracture compliance. Apart from aperrms, the simulations show that in clay rocks, plastic deformation plays an important role in the closure of fractures by compression. In agreement with the experiments, the simulations predict that the permeability falls below 10% of the initial value at a compressive stress of 5 MPa. The simulations predict that fracture closure by swelling is rather ineffective for confining pressures exceeding ∼1 MPa.
Particle tracking as a vulnerability assessment tool for drinking water production
Authors: Pryet Alexandre , Matran Pierre , Cousquer Yohann , Roubinet Delphine
Published: August 2022

The simulation of concentration values and use of such data for history-matching is often impeded by the computation time of groundwater transport models based on the resolution of the advection-dispersion equation. This is unfortunate because such data are often rich in information and the prediction of concentration values is of great interest for decision making. Particle tracking can be used as an efficient alternative under a series of simplifying assumptions, which are often reasonable at groundwater sinks (wells and drains). Our approach consists of seeding particles around a sink and tracking particles backward, up to the source boundary condition, such as a contaminated stream. This particle tracking approach allows the use of parameter estimation and optimization methods requiring numerous model calls. We present a Python module facilitating the pre- and post-processing operations of a modeling workflow based on the widely used USGS MODFLOW6 and MODPATH7 programs. The module handles particle seeding around the sink and estimation of the mixing ratio of water withdrawn from the sink. This ratio is computed with a mixing law from the particle endpoints, accounting for particle velocities and mixing in the source model cells. We investigate the best practice to obtain robust derivatives with this approach, which is a benefit for the screening methods based on linear analysis. We illustrate the interest of the approach with a real world case study, considering a drinking water well field vulnerable to a contaminated stream. The configuration is typical of many other drinking water production sites. The modeling workflow is fully script-based to make the approach easily reproducible in similar cases.
A novel CO2 sensitive and recyclable viscoelastic fluid system for fracturing
Authors: Wu Baizhi , Sun Xin , Dai Caili , Hou Shugang , Du Huanfu
Published: August 2022

Hydraulic fracturing is one of the most commonly used processes of stimulating oil and gas wells to improve the production in low permeability reservoirs or damaged wells. In response to the serious water waste caused by the flowback fluid after the fracturing operation and the huge environmental pressure, a novel CO2 sensitive and recyclable viscoelastic fracturing fluid was developed. This CO2 sensitive property allows fracturing fluids to be recycled. The system consists of viscoelastic surfactants called fatty methyl ester sulfonates (FMES), triethylenetetramine and NaCl. The system shows a strong sensitivity to CO2. When the system is repeatedly contacted and separated from CO2, the viscosity rises and falls rapidly and regularly. The experiments of viscoelasticity, shear resistance and microstructure confirmed that the increasing viscosity of the system after contacting with CO2 was caused by the formation of viscoelastic fluid. When the system leak-off into the formation matrix, the microstructure of the system will be rapidly destroyed under the action of hydrocarbons, and the viscosity will drop to 1.225 mPa·s. Low viscosity after destroying reduces the retention of the system in the formation, resulting in formation damage rate of less than 35%. This research not only provides high-performance, low-cost fracturing fluids, but also provides new insights for the recovery and utilization of fracturing fluids.