Fluorescence probe for real-time malonaldehyde detection in epilepsy model.

Oxidative stress, a condition involving an imbalance between reactive oxygen species (ROS) and antioxidants, is closely linked to epilepsy, contributing to abnormal neuronal excitability. This study introduces a novel fluorescent probe, the MDP probe, designed for the efficient detection of malondialdehyde (MDA), a critical biomarker associated with oxidative stress. The MDP probe offers several key advantages, including high sensitivity with a low detection limit of 0.08 µM for MDA, excellent selectivity for MDA even in the presence of interfering substances, and biocompatibility, making it suitable for cell-based experiments. The probe allows for real-time monitoring of MDA levels, enabling dynamic studies of oxidative stress. In vivo experiments in mice demonstrate its potential for monitoring MDA levels, particularly in epilepsy models, which could have implications for disease research and diagnosis. Overall, the MDP probe represents a promising tool for studying oxidative stress, offering sensitivity and specificity in cellular and in vivo settings. Its development opens new avenues for exploring the role of oxidative stress in various biological processes and diseases, contributing to advancements in healthcare and biomedical research.

Aberrant degree centrality profiles during rumination in major depressive disorder.

Rumination is closely linked to the onset and maintenance of major depressive disorder (MDD). Prior neuroimaging studies have identified the association between self-reported rumination trait and the functional coupling among a network of brain regions using resting-state functional magnetic resonance imaging (MRI). However, little is known about the underlying neural circuitry mechanism during active rumination in MDD. Degree centrality (DC) is a simple metric to denote network integration, which is critical for higher-order psychological processes such as rumination. During an MRI scan, individuals with MDD (N = 45) and healthy controls (HC, N = 46) completed a rumination state task. We examined the interaction effect between the group (MDD vs. HC) and condition (rumination vs. distraction) on vertex-wise DC. We further characterized the identified brain region's functional involvement with Neurosynth and BrainMap. Network-wise seed-based functional connectivity (FC) analysis was also conducted for the identified region of interest. Finally, exploratory correlation analysis was conducted between the identified region of interest's network FCs and self-reported in-scanner affect levels. We found that a left superior frontal gyrus (SFG) region, generally overlapped with the frontal eye field, showed a significant interaction effect. Further analysis revealed its involvement with executive functions. FCs between this region, the frontoparietal, and the dorsal attention network (DAN) also showed significant interaction effects. Furthermore, its FC to DAN during distraction showed a marginally significant negative association with in-scanner affect level at the baseline. Our results implicated an essential role of the left SFG in the rumination's underlying neural circuitry mechanism in MDD and provided novel evidence for the conceptualization of rumination in terms of impaired executive control.

The potential role of subseafloor fungi in driving the biogeochemical cycle of nitrogen under anaerobic conditions.

Fungi represent the dominant eukaryotic group of organisms in anoxic marine sedimentary ecosystems, ranging from a few centimeters to ~ 2.5 km below seafloor. However, little is known about how fungi can colonize anaerobic subseafloor environments for tens of millions of years and whether they play a role in elemental biogeochemical cycles. Based on metabolite detection, isotope tracer and gene analysis, we examined the anaerobic nitrogen conversion pathways of 19 fungal species (40 strains) isolated from1.3 to 2.5 km coal-bearing sediments below seafloor. Our results show for the first time that almost all fungi possess anaerobic denitrification, dissimilatory nitrate reduction to ammonium (DNRA), and nitrification pathways, but not anaerobic ammonium oxidation (anammox). Moreover, the distribution of fungi with different nitrogen-conversion abilities in subseafloor sediments was mainly determined by in situ temperature, CaCO3, and inorganic carbon contents. These findings suggest that fungi have multiple nitrogen transformation processes to cope with their requirements for a variety of nitrogen sources in nutrient deficient anaerobic subseafloor sedimentary environments.

Genomic insights into Aspergillus sydowii 29R-4-F02: unraveling adaptive mechanisms in subseafloor coal-bearing sediment environments.

Introduction: Aspergillussydowii is an important filamentous fungus that inhabits diverse environments. However, investigations on the biology and genetics of A. sydowii in subseafloor sediments remain limited. Methods: Here, we performed de novo sequencing and assembly of the A. sydowii 29R-4-F02 genome, an isolate obtained from approximately 2.4 km deep, 20-million-year-old coal-bearing sediments beneath the seafloor by employing the Nanopore sequencing platform. Results and Discussion: The generated genome was 37.19 Mb with GC content of 50.05%. The final assembly consisted of 11 contigs with N50 of 4.6 Mb, encoding 12,488 putative genes. Notably, the subseafloor strain 29R-4-F02 showed a higher number of carbohydrate-active enzymes (CAZymes) and distinct genes related to vesicular fusion and autophagy compared to the terrestrial strain CBS593.65. Furthermore, 257 positively selected genes, including those involved in DNA repair and CAZymes were identified in subseafloor strain 29R-4-F02. These findings suggest that A. sydowii possesses a unique genetic repertoire enabling its survival in the extreme subseafloor environments over tens of millions of years.

Magnetic resonance imaging focused on the ferritin heavy chain 1 reporter gene detects neuronal differentiation in stem cells.

The neuronal differentiation of mesenchymal stem cells offers a new strategy for the treatment of neurological disorders. Thus, there is a need to identify a noninvasive and sensitive in vivo imaging approach for real-time monitoring of transplanted stem cells. Our previous study confirmed that magnetic resonance imaging, with a focus on the ferritin heavy chain 1 reporter gene, could track the proliferation and differentiation of bone marrow mesenchymal stem cells that had been transduced with lentivirus carrying the ferritin heavy chain 1 reporter gene. However, we could not determine whether or when bone marrow mesenchymal stem cells had undergone neuronal differentiation based on changes in the magnetic resonance imaging signal. To solve this problem, we identified a neuron-specific enolase that can be differentially expressed before and after neuronal differentiation in stem cells. In this study, we successfully constructed a lentivirus carrying the neuron-specific enolase promoter and expressing the ferritin heavy chain 1 reporter gene; we used this lentivirus to transduce bone marrow mesenchymal stem cells. Cellular and animal studies showed that the neuron-specific enolase promoter effectively drove the expression of ferritin heavy chain 1 after neuronal differentiation of bone marrow mesenchymal stem cells; this led to intracellular accumulation of iron and corresponding changes in the magnetic resonance imaging signal. In summary, we established an innovative magnetic resonance imaging approach focused on the induction of reporter gene expression by a neuron-specific promoter. This imaging method can be used to noninvasively and sensitively detect neuronal differentiation in stem cells, which may be useful in stem cell-based therapies.

Network analysis and experimental pharmacology study explore the protective effects of Isoliquiritigenin on 5-fluorouracil-Induced intestinal mucositis.

5-fluorouracil (5-FU) is one of the most widely used chemotherapy drugs for malignant tumors. However, intestinal mucositis caused by 5-FU is a severe dose-limiting toxic effect and even leads to treatment interruption. Isoliquiritigenin (ISL) is one of the main active compounds of licorice, which is a traditional Chinese herbal medicine commonly used in inflammation and gastrointestinal diseases. It is speculated that ISL have protective effects on intestinal mucositis. However, no such studies have been reported. Therefore, to investigate the impact of ISL on 5-Fu-induced intestinal mucositis, a strategy based on network prediction and pharmacological experimental validation was proposed in this study. Firstly, the targets and mechanism of ISL in alleviating 5-Fu-induced gastrointestinal toxicity were predicted by network analysis. And the results were further confirmed by molecular docking. Then, a mouse model of intestinal mucositis was established by intraperitoneal injection of 5-FU (384 µmol/kg) to verify the prediction of network analysis. The network analysis results suggested that PTGS2 (Prostaglandin G/H synthase 2) and NOS2 (Nitric oxide synthase, inducible) might be the critical targets of ISL for reducing the intestinal toxicity of 5-FU. In addition, KEGG and GO enrichment analysis revealed that the HIF-1, TNF, MAPK, IL-17, PI3K-Akt, Ras, NF-kappa B signaling pathway, and biological processes of the inflammatory response, apoptosis regulation, NO production and NF-kappa B transcription factor activity might be involved in the mechanism of ISL against intestinal mucositis. Subsequent animal experiments showed that ISL could reduce the weight loss, leukopenia and mucosal damage caused by 5-FU. Compared with the intestinal mucositis model, the protein expressions of PTGS2, NOS2, TNFα (Tumor necrosis factor-alpha) and NF-κB p65 (nuclear factor kappa-B P65) were decreased after ISL treatment. In conclusion, this study is the fist time to find that ISL can attenuate 5-FU-induced intestinal mucositis in mice. Its anti-mucositis effect may be through regulating TNF/NF-κB pathway and inhibiting inflammatory mediators PTGS2 and NOS2. It will provide a potential candidate for the prevention and treatment of chemotherapy-induced intestinal mucositis.

Calycosin suppresses colorectal cancer progression by targeting ERß, upregulating PTEN, and inhibiting PI3K/Akt signal pathway.

High intake of phytoestrogen has been reported to be associated with the prevention of colorectal cancer (CRC). Calycosin belongs to the phytoestrogen that has been shown to suppress CRC cells in our previous study. However, its anticancer activity and molecular mechanisms have not been elucidated. In this study, we analyzed the effect of calycosin on the viability and apoptosis of human CRC HCT116 and SW480 cells via MTT assay, flow cytometry assay, and caspase-3/7 activity assay. The protein expressions of estrogen receptor ß (ERß), PTEN, and PI3K/Akt signal pathways were determined by Western blot analysis. And then, the alterations of biological behavior in CRC cells transfected with ERß siRNA were analyzed. Mouse xenograft models were further performed to detect the antitumor effect in vivo. The results show that calycosin reduces CRC cell viability, induces cell apoptosis, and suppresses xenograft tumor growth. The protein expressions of ERß and PTEN are significantly upregulated following calycosin treatment, whereas p-AKT/AKT ratio and Bcl-2 level are downregulated. Suppressing ERß with siRNA partially attenuates the reduction in viability and apoptosis induced by calycosin. Our results indicate that calycosin shows inhibitory effects on CRC cells, which might be obtained by targeting ERß, upregulating PTEN, and inhibiting the PI3K/Akt signal pathway.

The DIRECT consortium and the REST-meta-MDD project: towards neuroimaging biomarkers of major depressive disorder.

Despite a growing neuroimaging literature on the pathophysiology of major depressive disorder (MDD), reproducible findings are lacking, probably reflecting mostly small sample sizes and heterogeneity in analytic approaches. To address these issues, the Depression Imaging REsearch ConsorTium (DIRECT) was launched. The REST-meta-MDD project, pooling 2428 functional brain images processed with a standardized pipeline across all participating sites, has been the first effort from DIRECT. In this review, we present an overview of the motivations, rationale, and principal findings of the studies so far from the REST-meta-MDD project. Findings from the first round of analyses of the pooled repository have included alterations in functional connectivity within the default mode network, in whole-brain topological properties, in dynamic features, and in functional lateralization. These well-powered exploratory observations have also provided the basis for future longitudinal hypothesis-driven research. Following these fruitful explorations, DIRECT has proceeded to its second stage of data sharing that seeks to examine ethnicity in brain alterations in MDD by extending the exclusive Chinese original sample to other ethnic groups through international collaborations. A state-of-the-art, surface-based preprocessing pipeline has also been introduced to improve sensitivity. Functional images from patients with bipolar disorder and schizophrenia will be included to identify shared and unique abnormalities across diagnosis boundaries. In addition, large-scale longitudinal studies targeting brain network alterations following antidepressant treatment, aggregation of diffusion tensor images, and the development of functional magnetic resonance imaging-guided neuromodulation approaches are underway. Through these endeavours, we hope to accelerate the translation of functional neuroimaging findings to clinical use, such as evaluating longitudinal effects of antidepressant medications and developing individualized neuromodulation targets, while building an open repository for the scientific community.

Identification of MKRN1 as a second E3 ligase for Eag1 potassium channels reveals regulation via differential degradation.

Mutations in the human gene encoding the neuron-specific Eag1 voltage-gated K+ channel are associated with neurodevelopmental diseases, indicating an important role of Eag1 during brain development. A disease-causing Eag1 mutation is linked to decreased protein stability that involves enhanced protein degradation by the E3 ubiquitin ligase cullin 7 (CUL7). The general mechanisms governing protein homeostasis of plasma membrane- and endoplasmic reticulum (ER)-localized Eag1 K+ channels, however, remain unclear. By using yeast two-hybrid screening, we identified another E3 ubiquitin ligase, makorin ring finger protein 1 (MKRN1), as a novel binding partner primarily interacting with the carboxyl-terminal region of Eag1. MKRN1 mainly interacts with ER-localized immature core-glycosylated, as well as nascent nonglycosylated, Eag1 proteins. MKRN1 promotes polyubiquitination and ER-associated proteasomal degradation of immature Eag1 proteins. Although both CUL7 and MKRN1 contribute to ER quality control of immature core-glycosylated Eag1 proteins, MKRN1, but not CUL7, associates with and promotes degradation of nascent, nonglycosylated Eag1 proteins at the ER. In direct contrast to the role of CUL7 in regulating both ER and peripheral quality controls of Eag1, MKRN1 is exclusively responsible for the early stage of Eag1 maturation at the ER. We further demonstrated that both CUL7 and MKRN1 contribute to protein quality control of additional disease-causing Eag1 mutants associated with defective protein homeostasis. Our data suggest that the presence of this dual ubiquitination system differentially maintains Eag1 protein homeostasis and may ensure efficient removal of disease-associated misfolded Eag1 mutant channels.

Significant Elevation in Potassium Concentration Surrounding Stimulated Excitable Cells Revealed by an Aptamer-Modified Nanowire Transistor.

Recording ion fluctuations surrounding biological cells with a nanoelectronic device offers seamless integration of nanotechnology into living organisms and is essential for understanding cellular activities. The concentration of potassium ion in the extracellular fluid (CK+ex) is a critical determinant of cell membrane potential and must be maintained within an appropriate range. Alteration in CK+ex can affect neuronal excitability, induce heart arrhythmias, and even trigger seizure-like reactions in the brain. Therefore, monitoring local fluctuations in real time provides an early diagnosis of the occurrence of the K+-induced pathophysiological responses. Here, we modified the surface of a silicon nanowire field-effect transistor (SiNW-FET) with K+-specific DNA-aptamers (AptK+) to monitor the real-time variations of CK+ex in primary cultured rat embryonic cortical neurons or human embryonic stem cell-derived cardiomyocytes. The binding affinity of AptK+ to K+, determined by measuring the dissociation constant of the AptK+-K+ complex (Kd = 10.1 ± 0.9 mM), is at least 38-fold higher than other ions (e.g., Na+, Ca2+, and Mg2+). By placing cultured cortical neurons over an AptK+/SiNW-FET device, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) stimulation raised the CK+ex dose-dependently to 16 mM when AMPA concentration was >10 µM; this elevation could be significantly suppressed by an AMPA receptor antagonist, 6,7-dinitroquinoxaline-2,3-dione. Likewise, the stimulation of isoproterenol to cardiomyocytes raised the CK+ex to 6-8 mM, with a concomitant increase in the beating rate. This study utilizing a robust nanobiosensor to detect real-time ion fluctuations surrounding excitable cells underlies the importance of ion homeostasis and offers the feasibility of developing an implant device for real-time monitoring.

Synthesis, G-Quadruplex DNA binding and cytotoxic properties of naphthalimide substituted styryl dyes.

G-Quadruplex DNAs, formed by G-rich DNA sequences in human genes, are promising targets for design of cancer drugs. In this study, two naphthalimide substituted styryl dyes with different sizes of aromatic groups were synthesized. The spectral analysis showed that the dye X-2 with a large aromatic group formed aggregates in buffer solution displaying very weak fluorescence intensity, and disaggregated in the presence of G-Quadruplex DNAs with large intensity enhancements (up to ~1800 fold). Moreover, X-2 displayed good selectivity to G-Quadruplex DNAs. In contrast, dye X-3 with the smaller aromatic group had much lower fluorescence enhancements and poor selectivity to G-Quadruplex DNAs, suggesting that the suitably sized aromatic ring was essential for the interaction with G-Quadruplex. Further binding studies suggested that X-2 mainly bound on G-quartet surface through end-stacking mode. Cytotoxicity assay showed that both of the two dyes showed good anti-proliferative activities against the cancer cell lines and less cytotoxicity in non-malignant cell lines, which were better than a standard drug 5-fluorouracil. In addition, living cell imaging was also studied and demonstrated the potential applications of the new dye X-2 in bioassays and cell imaging.

FKBP8 Enhances Protein Stability of the CLC-1 Chloride Channel at the Plasma Membrane.

Mutations in the skeletal muscle-specific CLC-1 chloride channel are associated with the human hereditary disease myotonia congenita. The molecular pathophysiology underlying some of the disease-causing mutations can be ascribed to defective human CLC-1 protein biosynthesis. CLC-1 protein folding is assisted by several molecular chaperones and co-chaperones, including FK506-binding protein 8 (FKBP8). FKBP8 is generally considered an endoplasmic reticulum- and mitochondrion-resident membrane protein, but is not thought to contribute to protein quality control at the cell surface. Herein, we aim to test the hypothesis that FKBP8 may regulate CLC-1 protein at the plasma membrane. Surface biotinylation and subcellular fractionation analyses reveal that a portion of FKBP8 is present at the plasma membrane, and that co-expression with CLC-1 enhances surface localization of FKBP8. Immunoblotting analyses of plasma membrane proteins purified from skeletal muscle further confirm surface localization of FKBP8. Importantly, FKBP8 promotes CLC-1 protein stability at the plasma membrane. Together, our data underscore the importance of FKBP8 in the peripheral quality control of CLC-1 channel.

The role of driver age in performance and attention allocation effects of roadway sign count, format and familiarity.

White-on-blue logo signs are used to inform drivers of food, gas, lodging, and attraction businesses at highway interchanges. In this study, 60 drivers were asked to look for food and attraction targets on logo signs while driving in a realistic freeway simulation. The objective of the study was to quantify effects of the number of sign panels (six vs. nine), logo familiarity (familiar vs. unfamiliar), logo format (text vs. pictorial), and driver age (young, middle, and elderly) on performance, attention allocation and target identification accuracy. Results revealed elderly drivers to exhibit worse performance in comparison to middle-age and young groups even though they adopted a more conservative driving strategy. There was no significant effect of the number of panels, logo familiarity, and logo format on driver performance or attention allocation. In target identification, drivers were more accurate with familiar or text-based panels appearing in six-panel signs.

The effects of interruption similarity and complexity on performance in a simulated visual-manual assembly operation.

The objective of the study was to assess the effects of interruption task similarity and complexity on performance of a simulated industrial assembly operation. Eighteen participants performed a simulated industrial assembly operation, including one trial with no interruption and eight others presenting an interruption task. Interruption conditions comprised a full crossing of task similarity to the primary assembly operation (similar, dissimilar) and complexity (simple, complex) with replication for each participant. Order of condition presentation was randomized. Findings revealed greater time to return to primary visual-manual assembly performance after a similar task interruption. Results also indicated complex interruptions may promote cognitive arousal that increases productivity following assembly interruptions. The majority of results are explained in terms of the Activation-Based Memory for Goals model. Findings provide some guidance for interruption management protocol design for workers engaged in procedural visual-manual assembly operations.

catena-Poly[(di-aqua-cadmium)-µ-iminodi-acetato-κ(4) O,N,O':O''].

In the title compound, [Cd(C4H5NO4)(H2O)2] n , the Cd(II) atom exhibits a distorted octa-hedral coordination geometry, defined by one N atom and three O atoms from two iminodi-acetate (IDA) ligands and two water molecules. The tridentate IDA ligand additionally bridges via one of its carboxylate O atoms to another Cd(II) atom, thus forming a zigzag chain along [001]. A three-dimensional network is completed by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds.

Protective effect of homonojirimycin from Commelina communis (dayflower) on influenza virus infection in mice.

The effects of homonojirimycin (HNJ), one of alkaloids from Commelina communis L., on protection against influenza virus infection in mice were investigated. HNJ was found to improve the survival rate, prolong the mean survival time and reduce virus yields in lungs on days 4 and 6 post-infection (p.i.), after the agent had been orally administered to the mice from 2 days before infection to 6 days p.i. Administration of HNJ (1 mg/kg) significantly increased interferon (IFN)-γ and interleukin (IL)-10 levels but decreased tumor necrosis factor (TNF)-α and IL-6 levels in serum and lungs of influenza-infected mice on days 2, 4 or 6 p.i. These results showed that HNJ exerted protection against influenza virus infection and produced effective immune responses in vivo.

Effect of total alkaloids from Commelina communis L. on lung damage by influenza virus infection.

Whether administration of total alkaloids from Commelina communis L. (TAC) reduces lung damage in influenza virus-infected mice was investigated. Compared with untreated mice, significantly less severe damage was found in the lungs of mice administered TAC at 8 mg/kg per day for 6 days. TAC significantly decreased viral loads in the lungs. The concentrations of IFN-γ in the serum of TAC-treated mice were significantly lower than those of virus control mice at 4 and 6 days post-infection. The results indicate that TAC imparted partial protection to the mice by reducing pulmonary viral loads and limiting lesions in the lungs.

Anti-influenza-virus activity of total alkaloids from Commelina communis L.

The antiviral activity of total alkaloids from Commelina communis L. (TAC) against influenza virus A/PR/8/34 (H1N1) was investigated in vitro and in vivo. TAC exhibited an inhibitory action on the growth of influenza virus in Madin-Darby canine kidney cells when added before or after viral infection. In mice infected with influenza virus, orally administered TAC at 8, 16 or 32 mg/kg per day for 6 days significantly increased the survival rate, prolonged the mean survival time and reduced the viral titers in the lung and the lung index, compared with that of the untreated virus control. The results obtained suggest that TAC has a pronounced protective effect against infection by influenza A virus.