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1.
Nature ; 597(7876): 393-397, 2021 09.
Article in English | MEDLINE | ID: mdl-34433967

ABSTRACT

Cellular dynamics and fate decision in early human embryogenesis remain largely unknown owing to the challenges of performing studies in human embryos1. Here, we explored whole-genomes of 334 single-cell colonies and targeted deep sequences of 379 bulk tissues obtained from various anatomical locations of seven recently deceased adult human donors. Using somatic mutations as an intrinsic barcode, we reconstructed early cellular phylogenies that demonstrate (1) an endogenous mutational rate that is higher in the first cell division but decreases to approximately one per cell per cell division later in life; (2) universal unequal contribution of early cells to embryo proper, resulting from early cellular bottlenecks that stochastically set aside epiblast cells within the embryo; (3) examples of varying degrees of early clonal imbalances between tissues on the left and right sides of the body, different germ layers and specific anatomical parts and organs; (4) emergence of a few ancestral cells that will substantially contribute to adult cell pools in blood and liver; and (5) presence of mitochondrial DNA heteroplasmy in the fertilized egg. Our approach also provides insights into the age-related mutational processes and loss of sex chromosomes in normal somatic cells. In sum, this study provides a foundation for future studies to complete cellular phylogenies in human embryogenesis.


Subject(s)
Cell Lineage/genetics , Clone Cells/metabolism , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Embryonic Development/genetics , Mutation , DNA, Mitochondrial/genetics , Embryo, Mammalian/embryology , Female , Humans , Male , Mutation Rate
2.
Proc Natl Acad Sci U S A ; 119(50): e2209586119, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36469787

ABSTRACT

Liquid mobility is ubiquitous in nature, with droplets emerging at all size scales, and artificial surfaces have been designed to mimic such mobility over the past few decades. Meanwhile, millimeter-sized droplets are frequently used for wettability characterization, even with facial mask applications, although these applications have a droplet-size target range that spans from millimeters to aerosols measuring less than a few micrometers. Unlike large droplets, microdroplets can interact sensitively with the fibers they contact with and are prone to evaporation. However, wetting behaviors at the single-microfiber level remain poorly understood. Herein, we characterized the wettability of fibrous layers, which revealed that a multiscale landscape of droplets ranged from the millimeter to the micrometer scale. The contact angle (CA) values of small droplets on pristine fibrous media showed sudden decrements, especially on a single microfiber, owing to the lack of air cushions for the tiny droplets. Moreover, droplets easily adhered to the pristine layer during droplet impact tests and then yielding widespread areas of contamination on the microfibers. To resolve this, we carved nanowalls on the pristine fibers by plasma etching, which effectively suppressed such wetting phenomena. Significantly, the resulting topographies of the microfibers managed the dynamic wettability of droplets at the multiscale, which reduced the probability of contamination with impact droplets and suppressed the wetting transition upon evaporation. These findings for the dynamic wettability of fibrous media will be useful in the fight against infectious droplets.


Subject(s)
Masks , Wettability , Physical Phenomena
3.
Anal Chem ; 96(40): 15924-15930, 2024 Oct 08.
Article in English | MEDLINE | ID: mdl-39299706

ABSTRACT

Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy is widely used to study condensed materials due to its convenient sample preparation and ability to avoid absorption saturation. Recently, it has been applied to in situ and in operando observations of chemical reactions within electrochemical devices, such as lithium-ion batteries. However, because ATR-FTIR spectroscopy relies on frequency-dependent attenuated reflectance, quantitative concentration measurements of chemical species using the Beer-Lambert law are challenging. Despite the availability of several correction methods, discrepancies remain in the solvation structures around Li+ ions when comparing transmission-type FTIR and ATR-FTIR spectroscopy results, which complicate the determination of solvation and desolvation energies. In this study, we investigate ATR-FTIR correction algorithms, elucidate the reasons for the discrepancies between ATR-FTIR and transmission FTIR spectroscopy results, and develop a method to correct the ATR-FTIR spectrum to accurately determine the solvation structures around Li+ ions.

5.
Oncology ; : 1-10, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39053443

ABSTRACT

INTRODUCTION: Reactive oxygen species modulator 1 (Romo1) is a novel protein that is critically involved in the intracellular production of reactive oxygen species. Evidence has revealed that Romo1 is associated with treatment outcomes of various human malignancies, including lung cancer. However, the clinical implications of this protein in surgically resected lung cancers harboring epidermal growth factor receptor (EGFR) mutations have not been investigated. METHODS: Data were collected from patients who underwent curative resection of EGFR-mutant lung adenocarcinoma. Romo1 protein expression levels were measured in the tumor tissue using immunohistochemical staining and evaluated semi-quantitatively using the histochemical score. Univariate and multivariate analyses were performed to identify the clinicopathological parameters that may be associated with clinical outcomes. RESULTS: A total of 98 samples were analyzed. Using the cutoff H score of 200, the population was classified into low (n = 73) and high (n = 25) Romo1 groups. Romo1 expression was significantly higher in smokers, patients with stage III disease, and patients who experienced recurrence after surgery (all p < 0.05). Multivariate analyses showed that advanced-stage and poorly differentiated cancers were associated with shorter disease-free survival (DFS). In addition, high Romo1 expression was independently associated with poor DFS (hazard ratio = 2.18, 95% confidence interval: 1.10-4.32, p = 0.0261). CONCLUSIONS: Our data showed that Romo1 overexpression was significantly associated with early recurrence in patients with resected EGFR-mutant lung adenocarcinoma. Although large-scale studies are required, Romo1 may play a prognostic role in this patient population.

6.
Bioorg Chem ; 144: 107109, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38219480

ABSTRACT

Herein, (-)-galiellalactone 1 congeners responsible for the nuclear factor erythroid 2-related factor 2 (Nrf2)-activating neuroprotective effects were elucidated. Additionally, novel congener-based Nrf2 activators were identified using a drug repositioning strategy. (-)-Galiellalactone, which comprises a tricyclic lactone skeleton, significantly activates antioxidant response element (ARE)-mediated transcription in neuroblastoma SH-SY5Y cells. Interestingly, two cyclohexene-truncated [3.3] bicyclic lactone analogs, which possess an exocyclic α-methylene-γ-butyrolactone moiety, exhibited higher Nrf2/ARE transcriptional activities than the parent (-)-galiellalactone. We confirmed that the cyclohexene moiety embedding the [3.3] bicyclic lactone congener does not play the essential role of (-)-galiellalactone for Nrf2/ARE activation. Nrf2/ARE activation by novel analogs resulted in the upregulation of downstream antioxidative and phase II detoxifying enzymes, heme oxygenase-1, and NAD(P)H quinone oxidoreductase 1, which are closely related to the cytoprotective effects on neurodegenerative diseases. (-)-Galiellalactone and its [3.3] bicyclic variants 3l and 3p increased the expression of antioxidant genes and exhibited neuroprotective effects against 6-hydroxydopamine-mediated neurotoxicity in the neuroblastoma SH-SY5Y cell line.


Subject(s)
Neuroblastoma , Neuroprotective Agents , Humans , NF-E2-Related Factor 2/metabolism , Neuroprotective Agents/pharmacology , Signal Transduction , Neuroblastoma/drug therapy , Antioxidants/pharmacology , Antioxidants/metabolism , Lactones/pharmacology , Lactones/chemistry , Cyclohexenes/pharmacology , Oxidative Stress , Cell Line, Tumor
7.
Neurol Sci ; 45(7): 3513-3516, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38589770

ABSTRACT

BACKGROUND: Transcranial direct current stimulation (tDCS) has been used for the restoration of awareness in patients with a minimal consciousness state (MCS). Most brains of patients in MCS may structurally and electrophysiologically differ from un-damaged brains. Moreover, tDCS is currently contraindicated for patients with craniotomy or skull with metallic implants. CASE PRESENTATION: We present a case with prolonged MCS over 1 year, who had severe brain damage, ventriculoperitoneal shunt, and cranioplasty with a titanium mesh, which was treated with tDCS which optimized with the simulation of the electric field based on the patient's brain MRI. The patient was resulting in emergence from MCS. Six months later, she ate meals orally and started walking with assistance. DISCUSSION AND PERSPECTIVE: This personalized simulation based on MRI would make the treatment available even to patients with severe brain structural changes and metallic instrumentation.


Subject(s)
Surgical Mesh , Titanium , Transcranial Direct Current Stimulation , Humans , Female , Transcranial Direct Current Stimulation/methods , Persistent Vegetative State/etiology , Persistent Vegetative State/therapy , Middle Aged , Consciousness Disorders/etiology , Consciousness Disorders/therapy
8.
Sensors (Basel) ; 24(19)2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39409253

ABSTRACT

Speaker recognition is a technology that identifies the speaker in an input utterance by extracting speaker-distinguishable features from the speech signal. Speaker recognition is used for system security and authentication; therefore, it is crucial to extract unique features of the speaker to achieve high recognition rates. Representative methods for extracting these features include a classification approach, or utilizing contrastive learning to learn the speaker relationship between representations and then using embeddings extracted from a specific layer of the model. This paper introduces a framework for developing robust speaker recognition models through contrastive learning. This approach aims to minimize the similarity to hard negative samples-those that are genuine negatives, but have extremely similar features to the positives, leading to potential mistaken. Specifically, our proposed method trains the model by estimating hard negative samples within a mini-batch during contrastive learning, and then utilizes a cross-attention mechanism to determine speaker agreement for pairs of utterances. To demonstrate the effectiveness of our proposed method, we compared the performance of a deep learning model trained with a conventional loss function utilized in speaker recognition with that of a deep learning model trained using our proposed method, as measured by the equal error rate (EER), an objective performance metric. Our results indicate that when trained with the voxceleb2 dataset, the proposed method achieved an EER of 0.98% on the voxceleb1-E dataset and 1.84% on the voxceleb1-H dataset.


Subject(s)
Speech , Humans , Speech/physiology , Algorithms , Deep Learning , Pattern Recognition, Automated/methods , Speech Recognition Software
9.
N Engl J Med ; 382(20): 1926-1932, 2020 05 14.
Article in English | MEDLINE | ID: mdl-32402162

ABSTRACT

We report the implantation of patient-derived midbrain dopaminergic progenitor cells, differentiated in vitro from autologous induced pluripotent stem cells (iPSCs), in a patient with idiopathic Parkinson's disease. The patient-specific progenitor cells were produced under Good Manufacturing Practice conditions and characterized as having the phenotypic properties of substantia nigra pars compacta neurons; testing in a humanized mouse model (involving peripheral-blood mononuclear cells) indicated an absence of immunogenicity to these cells. The cells were implanted into the putamen (left hemisphere followed by right hemisphere, 6 months apart) of a patient with Parkinson's disease, without the need for immunosuppression. Positron-emission tomography with the use of fluorine-18-L-dihydroxyphenylalanine suggested graft survival. Clinical measures of symptoms of Parkinson's disease after surgery stabilized or improved at 18 to 24 months after implantation. (Funded by the National Institutes of Health and others.).


Subject(s)
Dopaminergic Neurons/cytology , Induced Pluripotent Stem Cells/transplantation , Parkinson Disease/therapy , Pars Compacta/cytology , Aged , Animals , Basal Ganglia/diagnostic imaging , Basal Ganglia/metabolism , Cell Differentiation , Disease Models, Animal , Dopaminergic Neurons/metabolism , Dopaminergic Neurons/transplantation , Follow-Up Studies , Humans , Induced Pluripotent Stem Cells/immunology , Male , Mice , Mice, SCID , Parkinson Disease/diagnostic imaging , Positron-Emission Tomography , Putamen/diagnostic imaging , Tomography, X-Ray Computed , Transplantation, Autologous , Transplantation, Homologous
10.
PLoS Pathog ; 17(12): e1010092, 2021 12.
Article in English | MEDLINE | ID: mdl-34914812

ABSTRACT

The development of safe and effective vaccines to prevent SARS-CoV-2 infections remains an urgent priority worldwide. We have used a recombinant vesicular stomatitis virus (rVSV)-based prime-boost immunization strategy to develop an effective COVID-19 vaccine candidate. We have constructed VSV genomes carrying exogenous genes resulting in the production of avirulent rVSV carrying the full-length spike protein (SF), the S1 subunit, or the receptor-binding domain (RBD) plus envelope (E) protein of SARS-CoV-2. Adding the honeybee melittin signal peptide (msp) to the N-terminus enhanced the protein expression, and adding the VSV G protein transmembrane domain and the cytoplasmic tail (Gtc) enhanced protein incorporation into pseudotype VSV. All rVSVs expressed three different forms of SARS-CoV-2 spike proteins, but chimeras with VSV-Gtc demonstrated the highest rVSV-associated expression. In immunized mice, rVSV with chimeric S protein-Gtc derivatives induced the highest level of potent neutralizing antibodies and T cell responses, and rVSV harboring the full-length msp-SF-Gtc proved to be the superior immunogen. More importantly, rVSV-msp-SF-Gtc vaccinated animals were completely protected from a subsequent SARS-CoV-2 challenge. Overall, we have developed an efficient strategy to induce a protective response in SARS-CoV-2 challenged immunized mice. Vaccination with our rVSV-based vector may be an effective solution in the global fight against COVID-19.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Vesicular stomatitis Indiana virus/genetics , Angiotensin-Converting Enzyme 2/genetics , Animals , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/genetics , Chlorocebus aethiops , Humans , Immunization , Mice , Mice, Inbred C57BL , Mice, Transgenic , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells , Viral Proteins/genetics , Viral Proteins/immunology
11.
Oncology ; 101(1): 49-58, 2023.
Article in English | MEDLINE | ID: mdl-36191562

ABSTRACT

INTRODUCTION: KRAS, BRAF, and DNA mismatch repair (MMR) mutations aid clinical decision-making for colorectal cancer (CRC) patients. To ensure accurate predictions, the prognostic utilities of these biomarkers and their combinations must be individualized for patients with various TNM stages. METHODS: Here, we retrospectively analyzed the clinicopathological features of 904 Korean CRC patients who underwent CRC surgery in three teaching hospitals from 2011 to 2013; we also assessed the prognostic utilities of KRAS, BRAF, and MMR mutations in these patients. RESULTS: The overall frequencies of KRAS and BRAF mutations were 35.8% and 3.2%, respectively. Sixty-nine patients (7.6%) lacking expression of ≥1 MMR protein were considered MMR protein deficient (MMR-D); the remaining patients were considered MMR protein intact. KRAS mutations constituted an independent risk factor for shorter overall survival (OS) in TNM stage I-IV and stage III patients. BRAF mutations were associated with shorter OS in TNM stage I-IV patients. MMR-D status was strongly positive prognostic in TNM stage I-II patients. DISCUSSION/CONCLUSION: To our knowledge, this is the first multicenter study to explore the prognostic utilities of KRAS, BRAF, and MMR statuses in Korean CRC patients. Various combinations of KRAS, BRAF, and DNA MMR mutations serve as genetic signatures that affect tumor behavior; they are prognostic in CRC patients.


Subject(s)
Colorectal Neoplasms , Proto-Oncogene Proteins B-raf , Humans , Prognosis , Proto-Oncogene Proteins B-raf/genetics , DNA Mismatch Repair/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/surgery , Colorectal Neoplasms/metabolism , Retrospective Studies , Mutation , Republic of Korea
12.
BMC Ophthalmol ; 23(1): 107, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36932350

ABSTRACT

BACKGROUND: Evaluate the visual outcomes of Ahmed glaucoma valve implantation (AGVI) in patients with neovascular glaucoma (NVG) who underwent diabetic vitrectomy and suggest appropriate AGVI timing. METHODS: Medical records of patients who underwent AGVI due to NVG after diabetic vitrectomy were reviewed. Successful intraocular pressure (IOP) control was defined as an IOP between 6 and 21 mmHg. Visual outcome was compared before NVG diagnosis and after AGVI, and the "favorable" visual outcome was defined as a postoperative deterioration in BCVA of less than 0.3 logMAR units compared to those before the development of NVG. Various factors including surgical timing were evaluated to identify the risk factors associated with unfavorable visual outcome. RESULTS: A total of 35 eyes were enrolled and divided into group 1(medically uncontrolled NVG group, IOP more than 30mmHg, 16 eyes) and group 2(NVG group responded well to the initial non-surgical treatment but eventually required AGVI, 19 eyes). Despite the favorable rate of normalization of post-AGVI IOP (85.7%), 43.8% in Group 1 and 26.3% in Group 2 showed unfavorable visual outcomes. In group 1, delayed surgical timing more than 1 week from the NVG diagnosis showed a significant association with unfavorable visual outcomes (P = 0.041). In group 2, poor patient compliance (follow up loss, refuse surgery) was the main factor of unfavorable visual outcomes. CONCLUSION: When NVG occurs in patients with proliferative diabetic retinopathy after vitrectomy, physicians should be cautious not to delay the surgical intervention, especially in patients with IOP of 30 or more despite non-surgical treatment. Early AGVI within six days might be necessary to preserve useful vision in these patients.


Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Glaucoma Drainage Implants , Glaucoma, Neovascular , Glaucoma , Humans , Glaucoma, Neovascular/diagnosis , Glaucoma, Neovascular/etiology , Glaucoma, Neovascular/surgery , Vitrectomy , Glaucoma/surgery , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/surgery , Diabetic Retinopathy/complications , Intraocular Pressure , Prognosis , Retrospective Studies
13.
Mar Drugs ; 21(5)2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37233475

ABSTRACT

This study aimed to elucidate the structural congeners of natural izenamides A, B, and C (1-3) responsible for cathepsin D (CTSD) inhibition. Structurally modified izenamides were synthesized and biologically evaluated, and their biologically important core structures were identified. We confirmed that the natural statine (Sta) unit (3S,4S)-γ-amino-ß-hydroxy acid is a requisite core structure of izenamides for inhibition of CTSD, which is closely related to the pathophysiological roles in numerous human diseases. Interestingly, the statine-incorporated izenamide C variant (7) and 18-epi-izenamide B variant (8) exhibited more potent CTSD-inhibitory activities than natural izenamides.


Subject(s)
Cathepsin D , Protease Inhibitors , Humans , Protease Inhibitors/pharmacology , Protease Inhibitors/chemistry
14.
Nano Lett ; 22(10): 4276-4284, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35500055

ABSTRACT

Ferroelectric nanomaterials offer the promise of switchable electronic properties at the surface, with implications for photo- and electrocatalysis. Studies to date on the effect of ferroelectric surfaces in electrocatalysis have been primarily limited to nanoparticle systems where complex interfaces arise. Here, we use MBE-grown epitaxial BaTiO3 thin films with atomically sharp interfaces as model surfaces to demonstrate the effect of ferroelectric polarization on the electronic structure, intermediate binding energy, and electrochemical activity toward the hydrogen evolution reaction (HER). Surface spectroscopy and ab initio DFT+U calculations of the well-defined (001) surfaces indicate that an upward polarized surface reduces the work function relative to downward polarization and leads to a smaller HER barrier, in agreement with the higher activity observed experimentally. Employing ferroelectric polarization to create multiple adsorbate interactions over a single electrocatalytic surface, as demonstrated in this work, may offer new opportunities for nanoscale catalysis design beyond traditional descriptors.

15.
Curr Issues Mol Biol ; 44(8): 3735-3745, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-36005151

ABSTRACT

This study aimed to evaluate whether genetic polymorphism is associated with an increased risk of infection, specifically post-stroke aspiration pneumonia. Blood samples were obtained from a total of 206 post-stroke participants (males, n = 136; mean age, 63.8 years). Genotyping was performed for catechol-O-methyltransferase (rs4680, rs165599), dopamine receptors (DRD1; rs4532, DRD2; rs1800497, DRD3; rs6280), brain-derived neurotrophic factor (rs6265), apolipoprotein E (rs429358, rs7412), and the interleukin-1 receptor antagonist gene (rs4251961). The subjects were stratified into two groups, aged < 65 (young) and ≥ 65 (elderly). Functional parameters and swallowing outcomes were measured at enrollment and at 3 months post-onset. The primary outcome was the incidence of aspiration pneumonia. Analysis of the association between genetic polymorphisms and aspiration pneumonia history showed that a minor C rs429358 allele was associated with the occurrence of aspiration pneumonia in the young group, both in the additive and the dominant models (odds ratio: 4.53; 95% CI: 1.60−12.84, p = 0.004). In the multivariable analysis, the minor C rs429358 allele increased the risk of post-stroke aspiration pneumonia in young stroke patients by 5.35 (95% CI: 1.64−20.88). In contrast, no such association was observed in the elderly group. Apolipoprotein E polymorphism may affect the risk of post-stroke aspiration pneumonia.

16.
Bioorg Chem ; 122: 105716, 2022 05.
Article in English | MEDLINE | ID: mdl-35303621

ABSTRACT

The discovery of small molecules that regulate specific neuronal phenotypes is important for the development of new therapeutic candidates for neurological diseases. Estrogen-related receptor γ (ERRγ), an orphan nuclear receptor widely expressed in the central nervous system (CNS), is closely related to the regulation of neuronal metabolism and differentiation. We previously reported that upregulation of ERRγ could enhance dopaminergic neuronal phenotypes in the neuroblastoma cell line, SH-SY5Y. In this study, we designed and synthesized a series of new ERRγ agonists using the X-ray crystal structure of the GSK4716-bound ERRγ complex and known synthetic ligands. Our new ERRγ agonists exhibited increased transcriptional activities of ERRγ. In addition, our molecular docking results supported the experimental findings for ERRγ agonistic activity of the potent analogue, 5d. Importantly, 5d not only enhanced the expression of dopaminergic neuronal-specific molecules, TH and DAT but also activated the relevant signaling events, such as the CREB-mediated signaling pathway. The results of the present study may provide useful clues for the development of novel ERRγ agonists for neurological diseases related to the dopaminergic nervous system.


Subject(s)
Dopaminergic Neurons , Receptors, Estrogen , Dopaminergic Neurons/metabolism , Molecular Docking Simulation , Phenotype , Receptors, Estrogen/metabolism , Up-Regulation
17.
Nature ; 532(7600): 480-3, 2016 Apr 28.
Article in English | MEDLINE | ID: mdl-27121841

ABSTRACT

The regulation of water content in polymeric membranes is important in a number of applications, such as reverse electrodialysis and proton-exchange fuel-cell membranes. External thermal and water management systems add both mass and size to systems, and so intrinsic mechanisms of retaining water and maintaining ionic transport in such membranes are particularly important for applications where small system size is important. For example, in proton-exchange membrane fuel cells, where water retention in the membrane is crucial for efficient transport of hydrated ions, by operating the cells at higher temperatures without external humidification, the membrane is self-humidified with water generated by electrochemical reactions. Here we report an alternative solution that does not rely on external regulation of water supply or high temperatures. Water content in hydrocarbon polymer membranes is regulated through nanometre-scale cracks ('nanocracks') in a hydrophobic surface coating. These cracks work as nanoscale valves to retard water desorption and to maintain ion conductivity in the membrane on dehumidification. Hydrocarbon fuel-cell membranes with surface nanocrack coatings operated at intermediate temperatures show improved electrochemical performance, and coated reverse-electrodialysis membranes show enhanced ionic selectivity with low bulk resistance.


Subject(s)
Membranes, Artificial , Nanotechnology , Polymers/chemistry , Water/analysis , Biomimetic Materials/chemistry , Biomimetics , Cactaceae/metabolism , Desiccation , Dialysis , Electrochemistry , Humidity , Hydrophobic and Hydrophilic Interactions , Plant Stomata/metabolism , Protons , Surface Properties , Temperature
18.
Molecules ; 27(19)2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36235197

ABSTRACT

This paper reports a concise and scalable method for the synthesis of the phytoestrogen 7,2'-dihydroxy-4',5'-dimethoxyisoflavanone 1 via an optimized synthetic route. Compound 1 was readily obtained in 11 steps and 11% overall yield on a gram scale from commercially available 3,4-dimethoxyphenol. The key features of the synthesis include the construction of the deoxybenzoin unit through a sequence of Claisen rearrangement, oxidative cleavage, and aryllithium addition and the efficient synthesis of the isoflavanone architecture from highly functionalized 2-hydroxyketone.


Subject(s)
Phytoestrogens , Phytoestrogens/pharmacology , Stereoisomerism
19.
BMC Oral Health ; 22(1): 454, 2022 10 25.
Article in English | MEDLINE | ID: mdl-36284294

ABSTRACT

BACKGROUND: Taking facial and intraoral clinical photos is one of the essential parts of orthodontic diagnosis and treatment planning. Among the diagnostic procedures, classification of the shuffled clinical photos with their orientations will be the initial step while it was not easy for a machine to classify photos with a variety of facial and dental situations. This article presents a convolutional neural networks (CNNs) deep learning technique to classify orthodontic clinical photos according to their orientations. METHODS: To build an automated classification system, CNNs models of facial and intraoral categories were constructed, and the clinical photos that are routinely taken for orthodontic diagnosis were used to train the models with data augmentation. Prediction procedures were evaluated with separate photos whose purpose was only for prediction. RESULTS: Overall, a 98.0% valid prediction rate resulted for both facial and intraoral photo classification. The highest prediction rate was 100% for facial lateral profile, intraoral upper, and lower photos. CONCLUSION: An artificial intelligence system that utilizes deep learning with proper training models can successfully classify orthodontic facial and intraoral photos automatically. This technique can be used for the first step of a fully automated orthodontic diagnostic system in the future.


Subject(s)
Artificial Intelligence , Deep Learning , Humans , Neural Networks, Computer , Face
20.
Plant Cell ; 30(8): 1848-1863, 2018 08.
Article in English | MEDLINE | ID: mdl-30065046

ABSTRACT

Crosstalk between signaling pathways is an important feature of complex regulatory networks. How signal crosstalk circuits are tailored to suit different needs of various cell types remains a mystery in biology. Brassinosteroid (BR) and abscisic acid (ABA) antagonistically regulate many aspects of plant growth and development through direct interactions between components of the two signaling pathways. Here, we show that BR and ABA synergistically regulate stomatal closure through crosstalk between the BR-activated kinase CDG1-LIKE1 (CDL1) and the OPEN STOMATA1 (OST1) of the ABA signaling pathway in Arabidopsis thaliana We demonstrate that the cdl1 mutant displayed reduced sensitivity to ABA in a stomatal closure assay, similar to the ost1 mutant. CDL1 and the BR receptor BR-INSENSITIVE1, but not other downstream components of the BR signaling pathway, were required for BR regulation of stomatal movement. Genetic and biochemical experiments demonstrated that CDL1 activates OST1 by phosphorylating it on residue Ser-7. BR increased phosphorylation of OST1, and the BR-induced OST1 activation was abolished in cdl1 mutants. Moreover, we found that ABA activates CDL1 in an OST1-dependent manner. Taken together, our findings illustrate a cell-type-specific BR signaling branch through which BR acts synergistically with ABA in regulating stomatal closure.


Subject(s)
Abscisic Acid/pharmacology , Brassinosteroids/pharmacology , Plant Stomata/metabolism , Arabidopsis/drug effects , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant/drug effects , Phosphorylation/drug effects , Signal Transduction/drug effects
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