464 research outputs found
Multispacecraft Remote Sensing and In Situ Observations of the 2020 November 29 Coronal Mass Ejection and Associated Shock: From Solar Source to Heliospheric Impacts
We investigate the source eruption, propagation and expansion
characteristics, and heliospheric impacts of the 2020 November 29 coronal mass
ejection (CME) and associated shock, using remote sensing and in situ
observations from multiple spacecraft. A potential--field source--surface model
is employed to examine the coronal magnetic fields surrounding the source
region. The CME and associated shock are tracked from the early stage to the
outer corona using extreme ultraviolet and white light observations. Forward
models are applied to determine the structures and kinematics of the CME and
the shock near the Sun. The shock shows an ellipsoidal structure, expands in
all directions, and encloses the whole Sun as viewed from both SOHO and STEREO
A, which results from the large expansion of the CME flux rope and its fast
acceleration. The structure and potential impacts of the shock are mainly
determined by its radial and lateral expansions. The CME and shock arrive at
Parker Solar Probe and STEREO A. Only based on the remote sensing observations,
it is difficult to predict whether and when the CME/shock would arrive at the
Earth. Combining Wind in situ measurements and WSA-ENLIL simulation results, we
confirm that the far flank of the CME (or the CME leg) arrives at the Earth
with no shock signature. These results highlight the importance of multipoint
remote sensing and in situ observations for determining the heliospheric
impacts of CMEs
Impact of intravenous administration of anisodamine on coronary microvascular dysfunction in patients with obstructive epicardial coronary artery disease after percutaneous coronary intervention
Purpose: To analyze intravenous administration of anisodamine’s impact on coronary microvasculardysfunction (CMD) in obstructive epicardial coronary artery disease (CAD) patients who had undergone percutaneous coronary intervention (PCI).Methods: Enrollment of 210 patients in Shanghai Chest Hospital, Shanghai Jiaotong University with CMD was done in a randomized-controlled study. They were divided randomly into groups, viz, anisodamine (A) group and nitrate (N) group. A 14-day course of treatment was carried out in each group. 99mTc-MIBI myocardial perfusion imaging (MPI), treadmill exercise test (TET) and two dimensional echocardiography (TDE) were performed, and the symptoms of angina pectoris were recorded before and after treatment according to the classification, frequency, and duration of angina, as defined by Canadian Cardiovascular Society (CCS).Results: After treatment, summed stress score (SSS) and summed rest score (SRS) of MPI in group A significantly decreased after treatment (p < 0.001, respectively) and were remarkably lower than those in group N (p < 0.001, respectively). The CCS class in group A improved after treatment (p < 0.001) and was also better than in group N (p < 0.001). The frequency and duration of angina attack in group A significantly reduced after treatment (p < 0.001, respectively) and were notably lower than in group N (p < 0.001, respectively). Left ventricular ejection fraction in group A after treatment was higher than that before treatment (p = 0.046) and than that in group N (p = 0.048). Furthermore, the side effects of anisodamine were slight and tolerable.Conclusion: Intravenous administration of anisodamine is a potentially suitable optional treatment for CMD in patients with obstructive epicardial CAD who have undergone PCI
-representations of two-matrix models with infinite set of variables
The Hermitian, complex and fermionic two-matrix models with infinite set of
variables are constructed. We show that these two-matrix models can be realized
by the -representations. In terms of the -representations, we derive the
compact expressions of correlators for these two-matrix models.Comment: 12 page
Renal medullary carcinomas harbor a distinct methylation phenotype and display aberrant methylation of genes related to early nephrogenesis
SIMPLE SUMMARY: Renal medullary carcinomas (RMC) are aggressive tumors of the kidneys, characterized by a loss of SMARCB1. As the tumors, arising predominantly in young males with sickle cell trait, are very rare and no standard method for detection or treatment has been described, prognosis for these patients is poor. We generated methylation profiles of seven RMC samples and compared the hitherto unexplored methylation landscape of these tumors to other renal tumors and malignant rhabdoid tumors as well as epithelioid sarcomas, constituting two prototypically SMARCB1 aberrant entities. Based on these valuable datasets, we found that—in accordance with the previous gene expression data—RMCs separate from other SMARCB1 deficient entities. In a focused analysis of genes that are important for nephrogenesis, we particularly detected genes that govern early nephrogenesis to be hypomethylated and expressed at high levels in RMCs. ABSTRACT: Renal medullary carcinomas (RMC) are rare aggressive tumors of the kidneys, characterized by a loss of SMARCB1. Characteristically, these tumors arise in patients with sickle cell trait or other hemoglobinopathies. Recent characterization efforts have unraveled oncogenic pathways that drive tumorigenesis. Among these, gene sets that characterize replicative stress and the innate immune response are upregulated in RMCs. Despite comprehensive genetic and transcriptomic characterizations, commonalities or differences to other SMARCB1 deficient entities so far have not been investigated. We analyzed the methylome of seven primary RMC and compared it to other SMARCB1 deficient entities such as rhabdoid tumors (RT) and epithelioid sarcomas using 850 K methylation arrays. Moreover, we evaluated the differential gene expression of RMC using RNA-sequencing in comparison to other rhabdoid tumors. In accordance with previous gene expression data, we found that RMCs separate from other SMARCB1 deficient entities, pointing to a potentially different cell of origin and a role of additional genetic aberrations that may drive tumorigenesis and thus alter the methylome when compared to rhabdoid tumors. In a focused analysis of genes that are important for nephrogenesis, we particularly detected genes that govern early nephrogenesis such as FOXI1 to be hypomethylated and expressed at high levels in RMC. Overall, our analyses underscore the fact that RMCs represent a separate entity with limited similarities to rhabdoid tumors, warranting specific treatment tailored to the aggressiveness of the disease
Association Analysis of NALCN
Background. A genome-wide association study (GWAS) demonstrated a possible association between cervical dystonia (CD) and a sodium leak channel, nonselective (NALCN) gene. However, the association between NALCN and CD was largely unknown in Asian population. The present study was carried out to examine the associations between the two single nucleotide polymorphisms (SNPs) rs1338041 and rs61973742 in the NALCN gene and CD in a Chinese population. Methods. In a cohort of 201 patients with isolated CD, we genotyped the two SNPs rs1338041 and rs61973742 using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). We also included 289 unrelated, age- and sex-matched healthy controls (HCs) from the same region. Result. No significant differences were observed in either the genotype distributions or the minor allele frequencies (MAFs) of the two SNPs between the CD patients and the HCs. There were no significant differences between early-onset and late-onset CD patients, between patients with and without a positive family history of dystonia, or between patients with and without tremor or sensory tricks. Conclusion. Lack of association between the SNPs of NALCN and CD suggests that the SNPs of NALCN do not play a role in CD in a Chinese population
Extramedullary versus intramedullary tibial alignment technique in total knee arthroplasty: A meta-analysis of randomized controlled trials
The aim of this study was to establish whether the use of an extramedullary or intramedullary tibial cutting guide leads to superior mechanical leg axis and implant positioning. A meta-analysis of six randomized controlled trials including 350 knees was performed. For the mechanical axis, frontal tibial component angle and tibial slope, there were no significant differences in the mean values or the number of outliers (±3°) between the extramedullary and intramedullary groups. A reduced tourniquet time was associated with the intramedullary guide. No significant difference in the complication rate was noted between the two groups. Neither extramedullary nor intramedullary tibial alignment was more accurate in facilitating the tibial cut. Use of an intramedullary guide results in a shorter tourniquet time and exhibits a similar complication rate as the extramedullary guide
A general model for collaboration networks
In this paper, we propose a general model for collaboration networks.
Depending on a single free parameter "{\bf preferential exponent}", this model
interpolates between networks with a scale-free and an exponential degree
distribution. The degree distribution in the present networks can be roughly
classified into four patterns, all of which are observed in empirical data. And
this model exhibits small-world effect, which means the corresponding networks
are of very short average distance and highly large clustering coefficient.
More interesting, we find a peak distribution of act-size from empirical data
which has not been emphasized before of some collaboration networks. Our model
can produce the peak act-size distribution naturally that agrees with the
empirical data well.Comment: 10 pages, 10 figure
Analysis of necroptosis-related prognostic genes and immune infiltration in idiopathic pulmonary fibrosis
BackgroundIPF is an undetermined, progressive lung disease. Necroptosis is a type of programmed apoptosis, which involved in the pathogenesis of lung diseases like COPD and ARDS. However, necroptosis in IPF have not been adequately studied. This study aimed to investigate the necroptosis in IPF and the relationship between necroptosis and immune infiltration, to construct a prognostic prediction model of IPF based on necroptosis-related genes.MethodsGSE110147 was downloaded from the GEO database and utilized to analyze the expression of necroptosis-related differentially expressed genes (NRDEGs). Then NRDEGs were used to construct protein-protein interaction (PPI) networks in the STRING database, and Cytoscape software was used to identify and visualize hub genes. Necroptosis-related prognosticgenes were explored in GSE70866, and a prognostic prediction model was constructed. The ImmuCellAI algorithm was utilized to analyze the landscape of immune infiltration in GSE110147. The single-cell RNA sequencing dataset GSE122960 was used to explore the association between necroptosis and type II alveolar epithelial cells (AT II) in IPF. The GSE213001 and GSE93606 were used for external validation. The expression of prognostic genes was quantified using RT-qPCRin the IPF A549 cell model, and was further verified by western blotting in the bleomycin-induced pulmonary fibrosis mouse model.ResultsIt was observed that necroptosis-related signaling pathways were abundantly enriched in IPF. 29 NRDEGs were screened, of which 12 showed consistent expression trends in GSE213001. Spearman correlation analysis showed that the expression of NRDEGs was positively correlated with the infiltration of proinflammatory immune cells, and negatively correlated with the infiltration of anti-inflammatory immune cells. NRDEGs, including MLKL, were highly expressed in AT II of fibrotic lung tissue. A necroptosis-related prediction model was constructed based on 4 NRDEGsby the cox stepwise regression. In the validation dataset GSE93606, the prognostic prediction model showed good applicability. The verification results of RT-qPCR and western blotting showed the reliability of most of the conclusions.ConclusionsThis study revealed that necroptosis existed in IPF and might occur in AT II. Necroptosis was associated with immune infiltration, suggesting that necroptosis of AT II might involve in IPF by activating immune infiltration and immune response
Astrocyte metabolism and signaling pathways in the CNS
Astrocytes comprise half of the cells in the central nervous system and play a critical role in maintaining metabolic homeostasis. Metabolic dysfunction in astrocytes has been indicated as the primary cause of neurological diseases, such as depression, Alzheimer’s disease, and epilepsy. Although the metabolic functionalities of astrocytes are well known, their relationship to neurological disorders is poorly understood. The ways in which astrocytes regulate the metabolism of glucose, amino acids, and lipids have all been implicated in neurological diseases. Metabolism in astrocytes has also exhibited a significant influence on neuron functionality and the brain’s neuro-network. In this review, we focused on metabolic processes present in astrocytes, most notably the glucose metabolic pathway, the fatty acid metabolic pathway, and the amino-acid metabolic pathway. For glucose metabolism, we focused on the glycolysis pathway, pentose-phosphate pathway, and oxidative phosphorylation pathway. In fatty acid metabolism, we followed fatty acid oxidation, ketone body metabolism, and sphingolipid metabolism. For amino acid metabolism, we summarized neurotransmitter metabolism and the serine and kynurenine metabolic pathways. This review will provide an overview of functional changes in astrocyte metabolism and provide an overall perspective of current treatment and therapy for neurological disorders
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