Identification of the principal neuropeptide MIP and its action pathway in larval settlement of the echiuran worm Urechis unicinctus.

BACKGROUND: Larval settlement and metamorphosis represent critical events in the life history of marine benthic animals. Myoinhibitory peptide (MIP) plays a pivotal role in larval settlement of marine invertebrates. However, the molecular mechanisms of MIP involved in this process are not well understood. RESULTS: In this study, we evaluated the effects of thirteen MIP mature peptides on triggering the larval settlement of Urechis unicinctus (Xenopneusta, Urechidae), and determined that MIP2 was the principal neuropeptide. Transcriptomic analysis was employed to identify differentially expressed genes (DEGs) between the MIP2-treated larvae and normal early-segmentation larvae. Both cAMP and calcium signaling pathways were enriched in the DEGs of the MIP2-treated larvae, and two neuropeptide receptor genes (Spr, Fmrfar) were up-regulated in the MIP2-treated larvae. The activation of the SPR-cAMP pathway by MIP2 was experimentally validated in HEK293T cells. Furthermore, fourteen cilia-related genes, including Tctex1d2, Cfap45, Ift43, Ift74, Ift22, Cav1 and Mns1, etc. exhibited down-regulated expression in the MIP2-treated larvae. Whole-mount in situ hybridization identified two selected ciliary genes, Tctex1d2 and Cfap45, were specially expressed in circumoral ciliary cells of the early-segmentation larvae. Knocking down Tctex1d2 mRNA levels by in vivo RNA interference significantly increased the larval settlement rate. CONCLUSION: Our findings suggest that MIP2 inhibits the function of the cilia-related genes, such as Tctex1d2, through the SPR-cAMP-PKA pathway, thereby inducing larval settlement in U. unicinctus. The study contributes important data to the understanding of neuropeptide regulation in larval settlement.

Transcatheter Closure of Atrial Septal Defects with Absent Aortic Rim and the Predictors of Right Atrial Reverse Remodeling: 5 Years Experience in China.

INTRODUCTION: Atrial septal defect (ASD) is one of the most common congenital heart malformations. Although not recommended, a significant proportion of patients with aortic root defects receive ASD closure, some of whom have improved right ventricular function. The study aimed to investigate the safety of interventional therapy in ASD patients with complete aortic rim deficiency and explore the predictors of right atrial (RA) non-reverse remodeling. METHODS: 1,011 patients with ASD who underwent transcatheter closure in the Department of Cardiology, Zhongshan Hospital, affiliated to Fudan University from June 2017 to June 2023 were enrolled in the study. They were divided into a complete aortic rim deficiency group and without absent aortic rim group. Furthermore, patients who had an enlarged RA in the absent aortic rim group were divided into two subgroups according to whether their RA remodeling was reversed post-procedure. Multivariate logistic regression was used to determine the predictors of RA reverse remodeling. RESULTS: During the 1-year follow-up, no major operative complications occurred in all patients with the absence of an aortic rim and a normal edge. After the operation, the right heart remodeling was significantly reversed, multivariate logistic regression analysis was performed, and it was found that no coronary heart disease before an operation, lower plasma creatinine level, and larger RA and RV dimensions were the predictive factors for the reverse of RA remodeling after treatment. CONCLUSION: Transcatheter closure of ASD with complete aortic rim deficiency is safe and feasible. For patients without coronary heart disease, the lower the creatinine value and the lower the tricuspid regurgitation before an operation, the more improvement of RA remodeling after the operation.

Left atrial appendage closure in a patient previously implanted with an interatrial shunt device: a case report.

Patients with previous interatrial shunt device (IASD) implantation may face greater challenges during future left atrial interventional procedures. Herein, we report the first case of left atrial appendage closure (LAAC) in a patient with previous IASD implantation. The patient successfully underwent LAAC using the LAmbre device without complications.

Activation of PKC affects the ventricular restitution properties and arrhythmogenesis through L-type Ca+ current.

OBJECTIVE: To investigate the role of protein kinase C (PKC) in action potential duration (APD) restitution and ventricular tachyarrhythmias (VAs). METHODS AND RESULTS: Rabbits hearts were isolated and prepared for Langendorff perfusion technique. The stimuli-extra-stimulus (S1-S2) method and dynamic S1 pacing protocol were performed to construct APD restitution and to induce APD alternans or VA, respectively, at 10 sites throughout the ventricular chamber. Administration of phorbol-12-myristate-13-acetate (PMA) (100 nM) (n = 15) greatly steepened the restitution curves (Smax > 1) (p < .01) at each site compared to the control group (n = 15). Furthermore, treatment with PMA also induced larger spatial dispersions of Smax (p < .05) and decreased the thresholds of the VA and APD alternans (p < .01). However, perfused with the PKC inhibitor, bisindolylmaleimide (BIM) (500 nM) (n = 10), reversibly flattened the APD restitution curves at each site (Smax < 1), decreased the spatial dispersions of Smax, and increased the thresholds of APD alternans and VA. According to the results of patch-clamp, peak amplitude of L-type Ca2+ current was significantly increased by addition of PMA compared with control (CTL) group (p < .05). Antagonize this current with verapamil (n = 10) can fully inhibited the PMA induced increasing of Smax and inducibility of VA and alternans. CONCLUSION: PKC activation increased the dispersion of APD restitution and thus led to occurrence of VA, which possibly related to the increased Ca2+ influx.

Targeting Macrophages: Therapeutic Approaches in Diabetic Kidney Disease.

Diabetes is not solely a metabolic disorder but also involves inflammatory processes. The immune response it incites is a primary contributor to damage in target organs. Research indicates that during the initial phases of diabetic nephropathy, macrophages infiltrate the kidneys alongside lymphocytes, initiating a cascade of inflammatory reactions. The interplay between macrophages and other renal cells is pivotal in the advancement of kidney disease within a hyperglycemic milieu. While M1 macrophages react to the inflammatory stimuli induced by elevated glucose levels early in the disease progression, their subsequent transition to M2 macrophages, which possess anti-inflammatory and tissue repair properties, also contributes to fibrosis in the later stages of nephropathy by transforming into myofibroblasts. Comprehending the diverse functions of macrophages in diabetic kidney disease and regulating their activity could offer therapeutic benefits for managing this condition.

Insights into the Molecular Mechanisms of NRF2 in Kidney Injury and Diseases.

Redox is a constant phenomenon in organisms. From the signaling pathway transduction to the oxidative stress during the inflammation and disease process, all are related to reduction-oxidation (redox). Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor targeting many antioxidant genes. In non-stressed conditions, NRF2 maintains the hemostasis of redox with housekeeping work. It expresses constitutively with basal activity, maintained by Kelch-like-ECH-associated protein 1 (KEAP1)-associated ubiquitination and degradation. When encountering stress, it can be up-regulated by several mechanisms to exert its anti-oxidative ability in diseases or inflammatory processes to protect tissues and organs from further damage. From acute kidney injury to chronic kidney diseases, such as diabetic nephropathy or glomerular disease, many results of studies have suggested that, as a master of regulating redox, NRF2 is a therapeutic option. It was not until the early termination of the clinical phase 3 trial of diabetic nephropathy due to heart failure as an unexpected side effect that we renewed our understanding of NRF2. NRF2 is not just a simple antioxidant capacity but has pleiotropic activities, harmful or helpful, depending on the conditions and backgrounds.

New Insights into the Treatment of Glomerular Diseases: When Mechanisms Become Vivid.

Treatment for glomerular diseases has been extrapolated from the experience of other autoimmune disorders while the underlying pathogenic mechanisms were still not well understood. As the classification of glomerular diseases was based on patterns of juries instead of mechanisms, treatments were typically the art of try and error. With the advancement of molecular biology, the role of the immune agent in glomerular diseases is becoming more evident. The four-hit theory based on the discovery of gd-IgA1 gives a more transparent outline of the pathogenesis of IgA nephropathy (IgAN), and dysregulation of Treg plays a crucial role in the pathogenesis of minimal change disease (MCD). An epoch-making breakthrough is the discovery of PLA2R antibodies in the primary membranous nephropathy (pMN). This is the first biomarker applied for precision medicine in kidney disease. Understanding the immune system's role in glomerular diseases allows the use of various immunosuppressants or other novel treatments, such as complement inhibitors, to treat glomerular diseases more reasonable. In this era of advocating personalized medicine, it is inevitable to develop precision medicine with mechanism-based novel biomarkers and novel therapies in kidney disease.

Lipid remodeling in response to methionine stress in MDA-MBA-468 triple-negative breast cancer cells.

Methionine (Met) is an essential amino acid and critical precursor to the cellular methyl donor S-adenosylmethionine. Unlike nontransformed cells, cancer cells have a unique metabolic requirement for Met and are unable to proliferate in growth media where Met is replaced with its metabolic precursor, homocysteine. This metabolic vulnerability is common among cancer cells regardless of tissue origin and is known as "methionine dependence", "methionine stress sensitivity", or the Hoffman effect. The response of lipids to Met stress, however, is not well-understood. Using mass spectroscopy, label-free vibrational microscopy, and next-generation sequencing, we characterize the response of lipids to Met stress in the triple-negative breast cancer cell line MDA-MB-468 and its Met stress insensitive derivative, MDA-MB-468res-R8. Lipidome analysis identified an immediate, global decrease in lipid abundances with the exception of triglycerides and an increase in lipid droplets in response to Met stress specifically in MDA-MB-468 cells. Furthermore, specific gene expression changes were observed as a secondary response to Met stress in MDA-MB-468, resulting in a downregulation of fatty acid metabolic genes and an upregulation of genes in the unfolded protein response pathway. We conclude that the extensive changes in lipid abundance during Met stress is a direct consequence of the modified metabolic profile previously described in Met stress-sensitive cells. The changes in lipid abundance likely results in changes in membrane composition inducing the unfolded protein response we observe.

Microhomology-based CRISPR tagging tools for protein tracking, purification, and depletion.

Work in yeast models has benefitted tremendously from the insertion of epitope or fluorescence tags at the native gene locus to study protein function and behavior under physiological conditions. In contrast, work in mammalian cells largely relies on overexpression of tagged proteins because high-quality antibodies are only available for a fraction of the mammalian proteome. CRISPR/Cas9-mediated genome editing has recently emerged as a powerful genome-modifying tool that can also be exploited to insert various tags and fluorophores at gene loci to study the physiological behavior of proteins in most organisms, including mammals. Here we describe a versatile toolset for rapid tagging of endogenous proteins. The strategy utilizes CRISPR/Cas9 and microhomology-mediated end joining repair for efficient tagging. We provide tools to insert 3×HA, His6FLAG, His6-Biotin-TEV-RGSHis6, mCherry, GFP, and the auxin-inducible degron tag for compound-induced protein depletion. This approach and the developed tools should greatly facilitate functional analysis of proteins in their native environment.

An Eddy Current-Based Structural Health Monitoring Technique for Tracking Bolt Cracking.

Bolted joints are the primary structures for the load transfer of large-scale structures. It is vital to monitor the process of bolt cracking for enduring structural safety. In this paper, a structural health monitoring technique based on the embedding eddy current sensing film has been proposed to quantify the crack parameters of bolt cracking. Two configurations of the sensing film containing one-dimensional circumferential coil array and two-dimensional coil array are designed and verified to have the ability to identify three crack parameters: the crack angle, the crack depth, and the crack location in the axial direction of the bolt. The finite element method has been employed not only to verify the capacity of the sensing film, but also to investigate the interaction between the crack and the eddy current/magnetic field. It has been demonstrated that as the crack propagates, the variations of the induced voltage of the sensing coils are influenced by both eddy current effect and magnetic flux leakage, which play different roles in the different periods of the crack propagation. Experiments have been performed to verify the effectiveness and feasibility of the sensing film to quantify three crack parameters in the process of the bolt cracking.

S-adenosylmethionine limitation induces p38 mitogen-activated protein kinase and triggers cell cycle arrest in G1.

The primary methyl group donor S-adenosylmethionine (SAM) is important for a plethora of cellular pathways including methylation of nucleic acids, proteins, and the 5' cap structure of mRNAs, as well as biosynthesis of phospholipids and polyamines. In addition, because it is the cofactor for chromatin methylation, SAM is an important metabolite for the establishment and maintenance of epigenetic marks. Here, we demonstrate that cells halt proliferation when SAM levels become low. Cell cycle arrest occurs primarily in the G1 phase of the cell cycle and is accompanied by activation of the mitogen-activated protein kinase p38 (MAPK14) and subsequent phosphorylation of MAPK-activated protein kinase-2 (MK2). Surprisingly, Cdk4 activity remains high during cell cycle arrest, whereas Cdk2 activity decreases concomitantly with cyclin E levels. Cell cycle arrest was induced by both pharmacological and genetic manipulation of SAM synthesis through inhibition or downregulation of methionine adenosyltransferase, respectively. Depletion of methionine, the precursor of SAM, from the growth medium induced a similar cell cycle arrest. Unexpectedly, neither methionine depletion nor inhibition of methionine adenosyltransferase significantly affected mTORC1 activity, suggesting that the cellular response to SAM limitation is independent from this major nutrient-sensing pathway. These results demonstrate a G1 cell cycle checkpoint that responds to limiting levels of the principal cellular methyl group donor S-adenosylmethionine. This metabolic checkpoint might play important roles in maintenance of epigenetic stability and general cellular integrity.

High-performance InGaN-based green light-emitting diodes with quaternary InAlGaN/GaN superlattice electron blocking layer.

In this study, high-performance InGaN-based green light-emitting diodes (LEDs) with a quaternary InAlGaN/GaN superlattice electron blocking layer (QSL-EBL) have been demonstrated. The band structural simulation was employed to investigate the electrostatic field and carriers distribution, show that the efficiency and droop behavior can be intensively improved by using a QSL-EBL in LEDs. The QSL-EBL structure can reduce the polarization-related electrostatic fields in the multiple quantum wells (MQWs), leading to a smoother band diagram and a more uniform carriers distribution among the quantum wells under forward bias. In comparison with green LEDs with conventional bulk-EBL structure, the light output power of LEDs with QSL-EBL was greatly enhanced by 53%. The efficiency droop shows only 30% at 100 A/cm2 comparing to its peak value, suggesting that the QSL-EBL LED is promising for future white lighting with high performance.

Fluoride coatings for vacuum ultraviolet reflection filters.

LaF3/MgF2 reflection filters with a high spectral-discrimination capacity of the atomic-oxygen lines at 130.4 and 135.6 nm, which were employed in vacuum ultraviolet imagers, were prepared by molybdenum-boat thermal evaporation. The optical properties of reflection filters were characterized by a high-precision vacuum ultraviolet spectrophotometer. The vulnerability of the filter's microstructures to environmental contamination and the recovery of the optical properties of the stored filter samples with ultraviolet ozone cleaning were experimentally demonstrated. For reflection filters with the optimized nonquarter-wave multilayer structures, the reflectance ratios R135.6 nm/R130.4 nm of 92.7 and 20.6 were achieved for 7° and 45° angles of incidence, respectively. On the contrary, R135.6 nm/R130.4 nm ratio of 12.4 was obtained for a reflection filter with a standard π-stack multilayer structure with H/L=1/4 at 7° AOI.

[Determination of five pesticides in fishpond by SPE-GC/MS].

OBJECTIVE: To establish the solid phase extraction (SPE) with GC/MS technology for fish poisoning cases to determine five pesticides in fishpond. METHODS: By three solid phase extraction column including Oasis HLB cartridge, Bond Elut C18 and SampliQ C18, the recovery rate was compared to extract and purify five pesticides in fishpond. The effects of different kinds and dosages of eluents on extract rate were also reviewed. RESULTS: Using Bond Elut C18 as solid phase extraction column and 3 mL benzene as eluent, the linear range of mass concentration of five pesticides in fishpond was 1-50 µg/mL, and the correlation coefficient was 0.996 2-0.999 6. The limit of detection was 3.4-26 µg/L and the recovery was 61.49%-102.48%. The relative standard deviations was less than or equal to 3.01%. CONCLU-SION: With high sensitivity, good accuracy and precision, SPE-GC/MS has simple and quick operation and less solvent. It can be applied to determination of five pesticides in fishpond.

Assemblathon 1: a competitive assessment of de novo short read assembly methods.

Low-cost short read sequencing technology has revolutionized genomics, though it is only just becoming practical for the high-quality de novo assembly of a novel large genome. We describe the Assemblathon 1 competition, which aimed to comprehensively assess the state of the art in de novo assembly methods when applied to current sequencing technologies. In a collaborative effort, teams were asked to assemble a simulated Illumina HiSeq data set of an unknown, simulated diploid genome. A total of 41 assemblies from 17 different groups were received. Novel haplotype aware assessments of coverage, contiguity, structure, base calling, and copy number were made. We establish that within this benchmark: (1) It is possible to assemble the genome to a high level of coverage and accuracy, and that (2) large differences exist between the assemblies, suggesting room for further improvements in current methods. The simulated benchmark, including the correct answer, the assemblies, and the code that was used to evaluate the assemblies is now public and freely available from http://www.assemblathon.org/.

Improvement of emission uniformity by using micro-cone patterned PDMS film.

Micro-patterned PDMS film was fabricated and combined with LED chip on board (COB) package to improve the emission uniformity of LED chip. The micro scale patterned sapphire substrate (PSS) was used as a mold to fabricate micro-cone patterned PDMS (MC-PDMS) film. A strong scattering effect from this MC-PDMS film can be verified by the high haze ratio and the Bi-directional Transmission effect. The angle dependent color temperature measurement system was used to measure the ΔCCT of COB with and without MC-PDMS. The measurement results indicate that the ΔCCT was reduced from 1025K to 428K. This improvement can effectively eliminate the yellow ring effect of LED chip. This technology can be thus considered as a cost-effective way for the next generation of light source packages.

Identifying human-rhesus macaque gene orthologs using heterospecific SNP probes.

We genotyped a Chinese and an Indian-origin rhesus macaque using the Affymetrix Genome-Wide Human SNP Array 6.0 and cataloged 85,473 uniquely mapping heterospecific SNPs. These SNPs were assigned to rhesus chromosomes according to their probe sequence alignments as displayed in the human and rhesus reference sequences. The conserved gene order (synteny) revealed by heterospecific SNP maps is in concordance with that of the published human and rhesus macaque genomes. Using these SNPs' original human rs numbers, we identified 12,328 genes annotated in humans that are associated with these SNPs, 3674 of which were found in at least one of the two rhesus macaques studied. Due to their density, the heterospecific SNPs allow fine-grained comparisons, including approximate boundaries of intra- and extra-chromosomal rearrangements involving gene orthologs, which can be used to distinguish rhesus macaque chromosomes from human chromosomes.

[Analysis of pesticides in blood specimen by GC/MS with accelerated solvent extraction].

OBJECTIVE: To develop the accelerated solvent extraction (ASE) for determining pesticides present in blood samples. METHODS: Pesticides were extracted by ASE with optimized parameters to study recovery rate affected by extraction temperature, time and agent. GC/MS was used to perform quantitative analysis. RESULTS: The recovery rates of eight pesticides were 70.6%-92.4%. The coefficient of variation was less than 5.0%. A good linear relationship was obtained at the concentration range of 0.5-5.0 microg/mL. CONCLUSION: The method was fast and simple with high recovery rate and good repeatability. It can be applied to analyze pesticides present in the blood specimen.

Remedy of a deep downward shift of a valve using double snares and "sandwich" technique.

A 76-year-old man diagnosed with severe pure native aortic regurgitation (PNAR) underwent transcatheter aortic valve replacement (TAVR) due to high surgical risk. The computed tomography angiography showed no calcification and no stenosis of the aortic valve, with an annulus perimeter of 81.1 mm and sinus diameters of 35 to 38 mm.

Genome-wide profiling of DNA methylome and transcriptome reveals epigenetic regulation of Urechis unicinctus response to sulfide stress.

Sulfide is a well-known environmental pollutant that can have detrimental effects on most organisms. However, few metazoans living in sulfide-rich environments have developed mechanisms to tolerate and adapt to sulfide stress. Epigenetic mechanisms, including DNA methylation, have been shown to play a vital role in environmental stress adaptation. Nevertheless, the precise function of DNA methylation in biological sulfide adaptation remains unclear. Urechis unicinctus, a benthic organism inhabiting sulfide-rich intertidal environments, is an ideal model organism for studying adaptation to sulfide environments. In this study, we conducted a comprehensive analysis of the DNA methylome and transcriptome of U. unicinctus after exposure to 50 µM sulfide. The results revealed dynamic changes in the DNA methylation (5-methylcytosine) landscape in response to sulfide stress, with U. unicinctus exhibiting elevated DNA methylation levels following stress exposure. Integrating differentially expressed genes (DEGs) and differentially methylated regions (DMRs), we identified a crucial role of gene body methylation in predicting gene expression. Furthermore, using a DNA methyltransferase inhibitor, we validated the involvement of DNA methylation in the sulfide stress response and the gene regulatory network influenced by DNA methylation. The results indicated that by modulating DNA methylation levels during sulfide stress, the expression of glutathione S-transferase, glutamyl aminopeptidase, and cytochrome c oxidase could be up-regulated, thereby facilitating the metabolism and detoxification of exogenous sulfides. Moreover, DNA methylation was found to regulate and enhance the oxidative phosphorylation pathway, including NADH dehydrogenase, isocitrate dehydrogenase, and ATP synthase. Additionally, DNA methylation influenced the regulation of Cytochrome P450 and macrophage migration inhibitory factor, both of which are closely associated with oxidative stress and stress resistance. Our findings not only emphasize the role of DNA methylation in sulfide adaptation but also provide novel insights into the potential mechanisms through which marine organisms adapt to environmental changes.