ABSTRACT
This study constructs a discrete-time Markov Chain (DTMC) model for a baseball plate appearance (PA) employing Major League Baseball's pitch-by-pitch dataset. Based on the DTMC model, we propose a novel measure for a baseball PA, termed the Importance of Moment (IOM). The IOM quantifies the criticality of each ball-strike count situation, by assessing the probabilistic difference between the pitcher's and hitter's favourable outcomes (out vs reaching base). If the favours significantly vary right after a particular ball-strike count, then the count is deemed critical and is assigned a high IOM value. We empirically verify that IOM explains pitchers' behaviour of fastball speed. We then further investigate whether the behaviour of ace pitchers differs significantly from the majority. Several interesting properties are found from the analysis. Firstly, the path independence assumption generally holds, with the exception of the ball-strike count of 2B1S. Second, pitchers tend to throw the faster fastball at counts with higher IOM values. Lastly, ace pitchers are capable of pitching even faster fastball in two-strike situations in which IOM is high. The DTMC effectively models the probabilistic structure of a baseball PA, and the proposed IOM measure serves as a useful tool for explaining player behaviour.
Subject(s)
Athletic Performance , Baseball , Markov Chains , Baseball/physiology , Humans , Athletic Performance/physiology , Competitive Behavior/physiologyABSTRACT
The COVID-19 pandemic has significantly impacted human health for three years. To mitigate the spread of SARS-CoV-2, the development of neutralizing antibodies has been accelerated, including the exploration of alternative antibody formats such as single-domain antibodies. In this study, we identified variable new antigen receptors (VNARs) specific for the receptor binding domain (RBD) of SARS-CoV-2 by immunizing a banded houndshark (Triakis scyllium) with recombinant wild-type RBD. Notably, the CoV2NAR-1 clone showed high binding affinities in the nanomolar range to various RBDs and demonstrated neutralizing activity against SARS-CoV-2 pseudoviruses. These results highlight the potential of the banded houndshark as an animal model for the development of VNAR-based therapeutics or diagnostics against future pandemics.
Subject(s)
COVID-19 , Single-Domain Antibodies , Humans , Animals , SARS-CoV-2/metabolism , Antibodies, Viral , Pandemics , Antibodies, NeutralizingABSTRACT
During postnatal neurodevelopment, excessive synapses must be eliminated by microglia to complete the establishment of neural circuits in the brain. The lack of synaptic regulation by microglia has been implicated in neurodevelopmental disorders such as autism, schizophrenia, and intellectual disability. Here we suggest that vaccinia-related kinase 2 (VRK2), which is expressed in microglia, may stimulate synaptic elimination by microglia. In VRK2-deficient mice (VRK2KO ), reduced numbers of presynaptic puncta within microglia were observed. Moreover, the numbers of presynaptic puncta and synapses were abnormally increased in VRK2KO mice by the second postnatal week. These differences did not persist into adulthood. Even though an increase in the number of synapses was normalized, adult VRK2KO mice showed behavioral defects in social behaviors, contextual fear memory, and spatial memory.
Subject(s)
Brain/enzymology , Brain/growth & development , Microglia/enzymology , Protein Serine-Threonine Kinases/metabolism , Synapses/enzymology , Animals , Brain/cytology , Cells, Cultured , Excitatory Postsynaptic Potentials/physiology , Fear/physiology , Humans , Male , Memory/physiology , Mice, Inbred C57BL , Mice, Knockout , Microglia/cytology , Miniature Postsynaptic Potentials/physiology , Protein Serine-Threonine Kinases/genetics , Social Behavior , Tissue Culture TechniquesABSTRACT
Vaccinia-related kinase 2 (VRK2) is a serine/threonine kinase that belongs to the casein kinase 1 family. VRK2 has long been known for its relationship with neurodegenerative disorders such as schizophrenia. However, the role of VRK2 and the substrates associated with it are unknown. Dysbindin is known as one of the strong risk factors for schizophrenia. The expression of dysbindin is indeed significantly reduced in schizophrenia patients. Moreover, dysbindin is involved in neurite outgrowth and regulation of NMDA receptor signaling. Here, we first identified dysbindin as a novel interacting protein of VRK2 through immunoprecipitation. We hypothesized that dysbindin is phosphorylated by VRK2 and further that this phosphorylation plays an important role in the function of dysbindin. We show that VRK2 phosphorylates Ser 297 and Ser 299 of dysbindin using in vitro kinase assay. In addition, we found that VRK2-mediated phosphorylation of dysbindin enhanced ubiquitination of dysbindin and consequently resulted in the decrease in its protein stability through western blotting. Over-expression of VRK2 in human neuroblastoma (SH-SY5Y) cells reduced neurite outgrowth induced by retinoic acid. Furthermore, a phosphomimetic mutant of dysbindin alleviated neurite outgrowth and affected surface expression of N-methyl-d-aspartate 2A, a subunit of NMDA receptor in mouse hippocampal neurons. Together, our work reveals the regulation of dysbindin by VRK2, providing the association of these two proteins, which are commonly implicated in schizophrenia. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
Subject(s)
Dysbindin/physiology , Protein Serine-Threonine Kinases/physiology , Protein Stability , Animals , Cell Line , Dysbindin/genetics , Hippocampus/cytology , Hippocampus/metabolism , Humans , Mice , Mice, Inbred C57BL , Mutation/genetics , Mutation/physiology , Neurites/drug effects , Phosphorylation , Protein Serine-Threonine Kinases/genetics , RNA, Small Interfering/pharmacology , Receptors, N-Methyl-D-Aspartate/biosynthesis , Tretinoin/pharmacology , UbiquitinationABSTRACT
While lipoplex (cationic lipid-nucleic acid complex)-mediated intracellular delivery is widely adopted in mammalian cell transfection, its transfection efficiency for suspension cells, e.g., lymphatic and hematopoietic cells, is reported at only ≈5% or even lower. Here, efficient and consistent lipoplex-mediated transfection is demonstrated for hard-to-transfect suspension cells via a single-cell, droplet-microfluidics approach. In these microdroplets, monodisperse lipoplexes for effective gene delivery are generated via chaotic mixing induced by the serpentine microchannel and co-confined with single cells. Moreover, the cell membrane permeability increases due to the shear stress exerted on the single cells when they pass through the droplet pinch-off junction. The transfection efficiency, examined by the delivery of the pcDNA3-EGFP plasmid, improves from ≈5% to ≈50% for all three tested suspension cell lines, i.e., K562, THP-1, Jurkat, and with significantly reduced cell-to-cell variation, compared to the bulk method. Efficient targeted knockout of the TP53BP1 gene for K562 cells via the CRISPR (clustered regularly interspaced short palindromic repeats)-CAS9 (CRISPR-associated nuclease 9) mechanism is also achieved using this platform. Lipoplex-mediated single-cell transfection via droplet microfluidics is expected to have broad applications in gene therapy and regenerative medicine by providing high transfection efficiency and low cell-to-cell variation for hard-to-transfect suspension cells.
Subject(s)
Microfluidics/methods , Transfection/methods , CRISPR-Associated Protein 9/genetics , CRISPR-Associated Protein 9/metabolism , Cell Membrane Permeability/physiology , Humans , K562 Cells , Regenerative MedicineABSTRACT
AIMS: Although peroxisome proliferator-activated receptors (PPARs)α/γ dual agonists can be beneficial for treatment of dyslipidemia in patients with type 2 diabetes, their use is limited owing to various side effects, including body weight gain, edema, and heart failure. We aimed to demonstrate that amodiaquine, an antimalarial agent, has potential as a PPARα/γ dual agonist with low risk of adverse effects. METHODS: We screened a Prestwick library (Prestwick Chemical; Illkirch, France) to identify novel PPARα/γ dual agonists and selected amodiaquine (4-[(7-chloroquinolin-4-yl)amino]-2-[(diethylamino)methyl]phenol), which activated both PPAR-α & -γ, for further investigation. We performed both in vitro, including glucose uptake assay and fatty acid oxidation assay, and in vivo studies to elucidate the anti-diabetic and anti-obesity effects of amodiaquine. RESULTS: Amodiaquine selectively activated the transcriptional activities of PPARα/γ and enhanced both fatty acid oxidation and glucose uptake without altering insulin secretion in vitro. In high-fat diet-induced obese and genetically modified obese/diabetic mice, amodiaquine not only remarkably ameliorated insulin resistance, hyperlipidemia, and fatty liver but also decreased body weight gain. CONCLUSION: Our findings suggest that amodiaquine exerts beneficial effects on glucose and lipid metabolism by concurrent activation of PPARα/γ. Furthermore, amodiaquine acts as an alternative insulin-sensitizing agent with a positive influence on lipid metabolism and has potential to prevent and treat type 2 diabetes while reducing the risk of lipid abnormalities.
Subject(s)
Amodiaquine/pharmacology , Antimalarials/pharmacology , Blood Glucose/drug effects , Insulin Resistance , Lipid Metabolism/drug effects , Liver/drug effects , PPAR alpha/agonists , PPAR gamma/agonists , 3T3-L1 Cells , Animals , Blood Glucose/metabolism , Body Weight , Cell Proliferation , Diet, High-Fat , Disease Models, Animal , Fatty Acids/metabolism , Fatty Liver , Hyperlipidemias , In Vitro Techniques , Liver/metabolism , Mice , Mice, Obese , Oxidation-Reduction , Triglycerides/metabolismABSTRACT
Vaccinia-related kinase 3 (VRK3) is known as a pseudokinase that is catalytically inactive due to changes in motifs that are essential for kinase activity. Although VRK3 has been regarded as a genuine pseudokinase from structural and biochemical studies, recent reports suggest that VRK3 acts as an active kinase as well as a signaling scaffold in cells. Here, we demonstrate that VRK3 phosphorylates the nuclear envelope protein barrier-to-autointegration factor (BAF) on Ser4. Interestingly, VRK3 kinase activity is dependent upon its N-terminal regulatory region, which is excluded from the determination of its crystal structure. Furthermore, the kinase activity of VRK3 is involved in the regulation of the cell cycle. VRK3 expression levels increase during interphase, whereas VRK1 is enriched in late G2 and early M phase. Ectopic expression of VRK3 induces the translocation of BAF from the nucleus to the cytoplasm. In addition, depletion of VRK3 decreases the population of proliferating cells. These data suggest that VRK3-mediated phosphorylation of BAF may facilitate DNA replication or gene expression by facilitating the dissociation of nuclear envelope proteins and chromatin during interphase.
Subject(s)
DNA-Binding Proteins/metabolism , Nuclear Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Cell Cycle , HEK293 Cells , HeLa Cells , Humans , Mice , Models, Biological , Nuclear Envelope/metabolism , Phosphorylation , Phosphoserine/metabolism , Protein Binding , Protein Serine-Threonine Kinases/chemistry , Protein Transport , Structure-Activity RelationshipABSTRACT
Monodispersed lipid vesicles have been used as a drug delivery vehicle and a biochemical reactor. To generate monodispersed lipid vesicles in the nano- to micrometer size range, an extrusion step should be included in conventional hand-shaking method of lipid vesicle synthesis. In addition, lipid vesicles as a drug carrier still need to be improved to effectively encapsulate concentrated biomolecules such as cells, proteins, and target drugs. To overcome these limitations, this paper reports a new microfluidic platform for continuous synthesis of small-sized (â¼10 µm) giant unilamellar vesicles (GUVs) containing quantum dots (QDs) as a nanosized model drug. To generate GUVs, we introduced an additional cross-flow to break vesicles into small size. 1,2 - dimyristoyl-sn-glycero - 3 - phosphocholine (DMPC) in an octanol-chloroform mixture was used in the construction of self-assembled membrane. Consequently, we have successfully demonstrated the fabrication of monodispersed GUVs with 7-12 µm diameter containing QDs. The proposed synthesis method of cell-sized GUVs would be highly desirable for applications such as multipurpose drug encapsulation and delivery.
Subject(s)
Drug Carriers/chemistry , Microfluidics/methods , Quantum Dots , Unilamellar Liposomes/chemistry , Dimyristoylphosphatidylcholine/chemistry , Drug Liberation , Lab-On-A-Chip Devices , Lipids/chemistry , Particle SizeABSTRACT
Rhythmic arylalkylamine N-acetyltransferase (AANAT) synthesis is a prominent circadian-controlled response that occurs in most mammals. AANAT is the core enzyme in melatonin production; because melatonin participates in many physiological processes, the regulation of AANAT is an important research topic. In this study, we focused on the role of heterogeneous ribonucleoprotein R (hnRNP R) in the translation of AANAT. A novel RNA-binding protein hnRNP R widely interacted with the 5' untranslated region (UTR) of AANAT mRNA and contributed to translation through an internal ribosomal entry site (IRES). Fine-tuning of AANAT protein synthesis occurred in response to knockdown and overexpression of hnRNP R. Nocturnal elevation of AANAT protein was dependent on the rhythmic changes of hnRNP R, whose levels are elevated in the pineal gland during nighttime. Increases in hnRNP R additionally improved AANAT production in rat pinealocytes under norepinephrine (NE) treatment. These results suggest that cap-independent translation of AANAT mRNA plays a role in the rhythmic synthesis of melatonin through the recruitment of translational machinery to hnRNP R-bound AANAT mRNA.
Subject(s)
Melatonin/metabolism , Animals , Arylalkylamine N-Acetyltransferase/metabolism , Blotting, Western , Cell Line , Humans , Immunohistochemistry , Internal Ribosome Entry Sites/genetics , Norepinephrine/pharmacology , Rats , Rats, Sprague-Dawley , Ribonucleoproteins/metabolismABSTRACT
BACKGROUND: Gromwell is known to have diverse pharmacological, cosmetic and nutritional benefits for humans. Nevertheless, the biological influence of gromwell extract (GE) on the general physiology of eukaryotic cells remains unknown. In this study a global transcriptome analysis was performed to identify genes affected by the addition of GE with Cryptococcus neoformans as the model system. RESULTS: In response to GE treatment, genes involved in signal transduction were immediately regulated, and the evolutionarily conserved sets of genes involved in the core cellular functions, including DNA replication, RNA transcription/processing and protein translation/processing, were generally up-regulated. In contrast, a number of genes involved in carbohydrate metabolism and transport, inorganic ion transport and metabolism, post-translational modification/protein turnover/chaperone functions and signal transduction were down-regulated. Among the GE-responsive genes that are also evolutionarily conserved in the human genome, the expression patterns of YSA1, TPO2, CFO1 and PZF1 were confirmed by northern blot analysis. Based on the functional characterization of some GE-responsive genes, it was found that GE treatment may promote cellular tolerance against a variety of environmental stresses in eukaryotes. CONCLUSIONS: GE treatment affects the expression levels of a significant portion of the Cryptococcus genome, implying that GE significantly affects the general physiology of eukaryotic cells.
Subject(s)
Adaptation, Physiological/genetics , Cryptococcus/drug effects , Eukaryotic Cells/drug effects , Lithospermum , Plant Extracts/pharmacology , Stress, Physiological/genetics , Transcriptome/drug effects , Biological Transport/drug effects , Biological Transport/genetics , Carbohydrate Metabolism/drug effects , Carbohydrate Metabolism/genetics , Cryptococcus/cytology , Cryptococcus/genetics , DNA Replication/drug effects , DNA Replication/genetics , Eukaryotic Cells/metabolism , Gene Expression/drug effects , Gene Expression Profiling , Gene Expression Regulation/drug effects , Genome , Oligonucleotide Array Sequence Analysis , Protein Biosynthesis/drug effects , Protein Biosynthesis/genetics , Protein Processing, Post-Translational/drug effects , Signal TransductionABSTRACT
In this paper, we propose a method for predicting epileptic seizures using a pre-trained model utilizing supervised contrastive learning and a hybrid model combining residual networks (ResNet) and long short-term memory (LSTM). The proposed training approach encompasses three key phases: pre-processing, pre-training as a pretext task, and training as a downstream task. In the pre-processing phase, the data is transformed into a spectrogram image using short time Fourier transform (STFT), which extracts both time and frequency information. This step compensates for the inherent complexity and irregularity of electroencephalography (EEG) data, which often hampers effective data analysis. During the pre-training phase, augmented data is generated from the original dataset using techniques such as band-stop filtering and temporal cutout. Subsequently, a ResNet model is pre-trained alongside a supervised contrastive loss model, learning the representation of the spectrogram image. In the training phase, a hybrid model is constructed by combining ResNet, initialized with weight values from the pre-trained model, and LSTM. This hybrid model extracts image features and time information to enhance prediction accuracy. The proposed method's effectiveness is validated using datasets from CHB-MIT and Seoul National University Hospital (SNUH). The method's generalization ability is confirmed through Leave-one-out cross-validation. From the experimental results measuring accuracy, sensitivity, and false positive rate (FPR), CHB-MIT was 91.90%, 89.64%, 0.058 and SNUH was 83.37%, 79.89%, and 0.131. The experimental results demonstrate that the proposed method outperforms the conventional methods.
Subject(s)
Epilepsy , Humans , Learning , Generalization, Psychological , Data Analysis , Seizures/diagnosisABSTRACT
IMPORTANCE: Feline calicivirus (FCV)-associated viral systemic disease (VSD) is a severe systemic disease caused by virulent FCV strains and has a very poor prognosis. OBJECTIVE: To evaluate the clinical characteristics of a nosocomial FCV-VSD outbreak involving 18 cats in Korea. METHODS: Medical records of cats diagnosed with FCV-VSD from March to September 2018 at a referral veterinary hospital were reviewed. The patient's signalment, history, clinical features, diagnosis, treatment, and prognosis were evaluated. RESULTS: Two outbreaks involving 18 cats diagnosed with FCV-VSD occurred over a 6-month period at a referral hospital in Korea. Anorexia, lethargy, fever, and limb edema were the most commonly observed clinical symptoms. Lymphopenia and macrothrombocytopenia were the most common hematological findings, and hyperbilirubinemia and increased levels of aspartate aminotransferase, creatine kinase, and serum amyloid A were the most frequent results of serum biochemistry. FCV was detected by reverse transcription polymerase chain reaction in 11 patients and the remaining 7 were suspected with FCV-VSD. The overall mortality rate was 72.2%. The hospital was closed and disinfected twice, and no additional outbreaks have occurred since the last patient. CONCLUSIONS AND RELEVANCE: The clinical and diagnostic characteristics and outcomes of FCV-VSD described in this study can be used to recognize and contain infectious diseases through quick action. To the best of the authors' knowledge, this is the first report of a nosocomial outbreak of FCV-VSD in Asia.
Subject(s)
Caliciviridae Infections , Calicivirus, Feline , Cat Diseases , Cross Infection , Disease Outbreaks , Cats , Republic of Korea/epidemiology , Disease Outbreaks/veterinary , Calicivirus, Feline/isolation & purification , Calicivirus, Feline/physiology , Cat Diseases/virology , Cat Diseases/epidemiology , Animals , Caliciviridae Infections/veterinary , Caliciviridae Infections/epidemiology , Caliciviridae Infections/virology , Male , Female , Cross Infection/veterinary , Cross Infection/virology , Cross Infection/epidemiologyABSTRACT
Among the inherited myopathies, a group of muscular disorders characterized by structural and metabolic impairments in skeletal muscle, Duchenne muscular dystrophy (DMD) stands out for its devastating progression. DMD pathogenesis is driven by the progressive degeneration of muscle fibers, resulting in inflammation and fibrosis that ultimately affect the overall muscle biomechanics. At the opposite end of the spectrum of muscle diseases, age-related sarcopenia is a common condition that affects an increasing proportion of the elderly. Although characterized by different pathological mechanisms, DMD and sarcopenia share the development of progressive muscle weakness and tissue inflammation. Here, the therapeutic effects of Cyclo Histidine-Proline (CHP) against DMD and sarcopenia are evaluated. In the mdx mouse model of DMD, it is shown that CHP restored muscle contractility and force production, accompanied by the reduction of fibrosis and inflammation in skeletal muscle. CHP furthermore prevented the development of cardiomyopathy and fibrosis in the diaphragm, the two leading causes of death for DMD patients. CHP also attenuated muscle atrophy and functional deterioration in a mouse model of age-related sarcopenia. These findings from two different models of muscle dysfunction hence warrant further investigation into the effects of CHP on muscle pathologies in animal models and eventually in patients.
Subject(s)
Disease Models, Animal , Mice, Inbred mdx , Muscle, Skeletal , Muscular Dystrophy, Duchenne , Sarcopenia , Animals , Mice , Muscular Dystrophy, Duchenne/genetics , Muscular Dystrophy, Duchenne/pathology , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Muscle, Skeletal/metabolism , Sarcopenia/pathology , Sarcopenia/prevention & control , Male , Mice, Inbred C57BLABSTRACT
Water evaporation-driven energy harvesting is an emerging mechanism for contributing to green energy production with low cost. Herein, we developed polyacrylonitrile (PAN) nanofiber-based evaporation-driven electricity generators (PEEGs) to confirm the feasibility of utilizing electrospun PAN nanofiber mats in an evaporation-driven energy harvesting system. However, PAN nanofiber mats require a support substrate to enhance its durability and stability when it is applied to an evaporation-driven energy generator, which could have additional effects on generation performance. Accordingly, various support substrates, including fiberglass, copper, stainless mesh, and fabric screen, were applied to PEEGs and examined to understand their potential impacts on electrical generation outputs. As a result, the PAN nanofiber mats were successfully converted to a hydrophilic material for an evaporation-driven generator by dip-coating them in nanocarbon black (NCB) solution. Furthermore, specific electrokinetic performance trends were investigated and the peak electricity outputs of Voc were recorded to be 150.8, 6.5, 2.4, and 215.9 mV, and Isc outputs were recorded to be 143.8, 60.5, 103.8, and 121.4 µA, from PEEGs with fiberglass, copper, stainless mesh, and fabric screen substrates, respectively. Therefore, the implications of this study would provide further perspectives on the developing evaporation-induced electricity devices based on nanofiber materials.
ABSTRACT
The commercialization of 3D heterogeneous integration through hybrid bonding has accelerated, and accordingly, Cu-polymer bonding has gained significant attention as a means of overcoming the limitations of conventional Cu-SiO2 hybrid bonding, offering high compatibility with other fabrication processes. Polymers offer robust bonding strength and a low dielectric constant, enabling high-speed signal transmission with high reliability, but suffer from low thermomechanical stability. Thermomechanical stability of polymers was not achieved previously because of thermal degradation and unstable anchoring. To overcome these limitations, wafer-scale Cu-polymer bonding via N-heterocyclic carbene (NHC) nanolayers was presented for 3D heterogeneous integration, affording ultrastable packing density, crystallinity, and thermal properties. NHC nanolayers were deposited on copper electrodes via electrochemical deposition, and wafer-scale 3D heterogeneous integration was achieved by adhesive bonding at 170 °C for 1 min. Ultrastable conductivity and thermomechanical properties were observed by the spatial mapping of conductivity, work function, and force-distance curves. With regard to the characterization of NHC nanolayers, low-temperature bonding, robust corrosion inhibition, enhanced electrical conductivity, back-end-of-line process compatibility, and fabrication process reduction, NHC Cu/polymer bonding provides versatile advances in 3D heterogeneous integration, indicating that NHC Cu/polymer bonding can be utilized as a platform for future 3D vertical chip architectures.
ABSTRACT
Microalgae, a group of microorganisms that grow using sunlight as the sole energy source and carbon dioxide as an only carbon source, have been considered as a feedstock of choice for the production of biofuels such as biodiesel. To explore the economic feasibility of such application, however, many technical hurdles must first be overcome; the selection and/or screening of competent species are some of the most important and yet challenging tasks. To greatly accelerate this rather slow and laborious step, we developed a droplet-based microfluidic system that uses alginate hydrogel microcapsules with a mean diameter of 26 µm, each of which is able to encapsulate a single microalgal cell. This novel device was successfully demonstrated using three microalgae species, namely, Chlorella vulgaris , Chlamydomonas sp., and Botryococcus braunii . In situ analysis of the lipid content of individual microalgal cells by nondestructive fluorescence staining using BODIPY (4,4-difluoro-1,3,5,7,-tetramethyl-4-bora-3a,4a-diaza-s-indacene) was possible. In all cases, we confirmed that the lipid content of microalgal species in alginate hydrogel microcapsules was comparable to that of free-living cells. Stochastic heterogeneity in the lipid content was verified under a highly viable physiological condition, implying that other analyses were possible after the determination of lipid content. Furthermore, the designed microwell arrays enabled us to distinguish the BODIPY fluorescence response of a single live alga within the microcapsules.
ABSTRACT
Microparticle adsorption on microchannel walls occurs frequently due to nonspecific interactions, decreasing operational performance in pressure-driven microfluidic systems. However, it is essential for delicate manipulation of microparticles or cells to maintain smooth fluid traffic. Here, we report a novel microparticle injection technique, which prevents particle loss, assisted by sample injection along the direction of fluid flow. Sample fluids, including microparticles, mammalian (U937), and green algae (Chlorella vulgaris) cells, were injected directly via a through hole drilled in the lateral direction, resulting in a significant reduction in microparticle attachment. For digital microfluidic application, the proposed regime achieved a twofold enhancement of single-cell encapsulation compared to the conventional encapsulation rate, based on a Poisson distribution, by reducing the number of empty droplets. This novel interconnection method can be straightforwardly integrated as a microparticle or cell injection component in integrated microfluidic systems.
Subject(s)
Cell Separation/instrumentation , Microfluidic Analytical Techniques/instrumentation , Adsorption , Cells, Cultured , Chlorella vulgaris/cytology , Dimethylpolysiloxanes , Equipment Design , Humans , Nylons , U937 CellsABSTRACT
Recently, photophysical property with fluorescence function has been attracted and studied because there are promising potentials in academic and industrial applications. Organic materials having fluorescence effect, especially fluorochromism can be utilized in the sensing or probing with absorption/emission changes. Herein, the prepared dye chromophore can be changed to their optical properties with polar/non-polar environmental media. In this work, we synthesized a new fluorochromism dye, namely 5-[2-(4-diphenylamino-phenyl)-vinyl]-2,2-dimethyl-[1,3]dioxane-4,6-dione using 3-formyl triphenylamine and 2,2-dimethyl-[1,3]dioxane-4,6-dione. We investigated absorption and fluorescent emission in various solvent media. Furthermore, cyclovoltammogram was used to determine energy levels of HOMO/LUMO from their redox onset potentials. Measured energy levels of HOMO/LUMO were compared with the results of simulated computational calculation.
ABSTRACT
Genetic information is transcribed from genomic DNA to mRNA, which is then translated into three-dimensional proteins. mRNAs can undergo various post-transcriptional modifications, including RNA editing that alters mRNA sequences, ultimately affecting protein function. In this study, RNA editing was identified at the 499th base (c.499) of human vaccinia-related kinase 2 (VRK2). This RNA editing changes the amino acid in the catalytic domain of VRK2 from isoleucine (with adenine base) to valine (with guanine base). Isoleucine-containing VRK2 has higher kinase activity than the valine-containing VRK2, which leads to an increase in tumor cell proliferation. Earlier we reported that VRK2 directly interacts with dystrobrevin-binding protein (dysbindin) and results in reducing its stability. Herein, we demonstrate that isoleucine-containing VRK2 decreases the level of dysbindin than valine-containing VRK2. Dysbindin interacts with cyclin D and thereby regulates its expression and function. The reduction in the level of dysbindin by isoleucine-containing VRK2 further enhances the cyclin D expression, resulting in increased tumor growth and reduction in survival rates. It has also been observed that in patient samples, VRK2 level was elevated in breast cancer tissue compared to normal breast tissue. Additionally, the isoleucine form of VRK2 exhibited a greater increase in breast cancer tissue. Therefore, it is concluded that VRK2, especially dependent on the 167th variant amino acid, can be one of the indexes of tumor progression and proliferation.
Subject(s)
Breast Neoplasms , Vaccinia , Humans , Female , Breast Neoplasms/genetics , Isoleucine , Dysbindin , Vaccinia virus , Amino Acids , Valine , Cyclin D , RNA, MessengerABSTRACT
Persistent damage to liver cells leads to liver fibrosis, which is characterized by the accumulation of scar tissue in the liver, ultimately leading to cirrhosis and serious complications. Because it is difficult to reverse cirrhosis once it has progressed, the primary focus has been on preventing the progression of liver fibrosis. However, studies on therapeutic agents for liver fibrosis are still lacking. Here, we investigated that the natural dipeptide cyclic histidine-proline (CHP, also known as diketopiperazine) shows promising potential as a therapeutic agent in models of liver injury by inhibiting the progression of fibrosis through activation of the Nrf2 pathway. To elucidate the underlying biological mechanism of CHP, we used the Cellular Thermal Shift Assay (CETSA)-LC-MS/MS, a label-free compound-based target identification platform. Chloride intracellular channel protein 1 (CLIC1) was identified as a target whose thermal stability is increased by CHP treatment. We analyzed the direct interaction of CHP with CLIC1 which revealed a potential interaction between CHP and the E228 residue of CLIC1. Biological validation experiments showed that knockdown of CLIC1 mimicked the antioxidant effect of CHP. Further investigation using a mouse model of CCl4-induced liver fibrosis in wild-type and CLIC1 KO mice revealed the critical involvement of CLIC1 in mediating the effects of CHP. Taken together, our results provide evidence that CHP exerts its anti-fibrotic effects through specific binding to CLIC1. These insights into the mechanism of action of CHP may pave the way for the development of novel therapeutic strategies for fibrosis-related diseases.