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1.
J Med Food ; 27(10): 931-939, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39058737

ABSTRACT

Ulcerative colitis (UC) is a subtype of inflammatory bowel disease affecting the colon with idiopathic origin. Melinjo endosperm extract (MeE) contains polyphenolic compounds that have antioxidative and anticancer properties. We examined the effect of MeE on inflammation and mucin expression in the colons of UC of mice treated with dextran sulfate sodium (DSS). C57BL/6J male mice were assigned into four categories: control, DSS + 0% MeE, DSS + 0.1% MeE, and DSS + 0.5% MeE. The control group was provided distilled water and a standard chow diet for 4 weeks. In DSS + 0% MeE, DSS + 0.1% MeE, and DSS + 0.5% MeE groups, the mice were treated with MeE for 3 weeks followed by MeE diets and drinking water containing 3% DSS for a week. Macrophage count, the mucus area stained by Alcian blue (AB), the levels of adenosine monophosphate-activated protein kinase (AMPK), nuclear factor-κB (NFκB) p65, and silent information regulator (Sirt) 1 protein expression, as well as proinflammatory mediators and Mucin 2 mRNA expression were assessed. In the DSS + 0% MeE group, the AB-stained areas and Mucin 2 mRNA expression levels were observed to be lower than those of controls. However, the levels in the +0.5% MeE group were significantly increased. Compared with the control group, the macrophage number, the expression of IL-1ß mRNA, and NFκB p65 protein in the DSS + 0% MeE group showed a significant increase. Conversely, these levels were significantly decreased in the +0.5% MeE group. The phosphorylated AMPK and Sirt1 protein levels were upregulated in the +0.5% MeE group. In conclusion, MeE may alleviate UC injury by reducing macrophage infiltration and regulating the AMPK/NFκB/Sirt1 pathway.


Subject(s)
AMP-Activated Protein Kinases , Disease Models, Animal , Gnetum , Mice, Inbred C57BL , NF-kappa B , Plant Extracts , Sirtuin 1 , Animals , Plant Extracts/pharmacology , Male , Sirtuin 1/metabolism , Sirtuin 1/genetics , Mice , AMP-Activated Protein Kinases/metabolism , NF-kappa B/metabolism , NF-kappa B/genetics , Gnetum/chemistry , Colon/drug effects , Colon/metabolism , Dextran Sulfate/adverse effects , Humans , Signal Transduction/drug effects , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/metabolism , Colitis/drug therapy , Colitis/chemically induced , Colitis/metabolism , Mucin-2/metabolism , Mucin-2/genetics , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Inflammation/drug therapy , Inflammation/metabolism
2.
J Am Chem Soc ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38848460

ABSTRACT

Cancer immune therapies, particularly programmed cell death protein 1 (PD-1) blockade immunotherapy, falter in aged individuals due to compromised T-cell immunity. Spermidine, a biogenic polyamine that declines along with aging, shows promise in restoring antitumor immunity by enhancing mitochondrial fatty acid oxidation (FAO). Herein, we report a spermidine-based chemoproteomic probe (probe 2) that enables profiling of spermidine-binding proteins and screening for small-molecule enhancers of mitochondrial FAO. Chemoproteomic profiling by the probe revealed 140 proteins engaged in cellular interaction with spermidine, with a significant majority being mitochondrial proteins. Hydroxyl coenzyme A (CoA) dehydrogenase subunits α (HADHA) and other lipid metabolism-linked proteins are among the mitochondrial proteins that have attracted considerable interest. Screening spermidine analogs with the probe led to the discovery of compound 13, which interacts with these lipid metabolism-linked proteins and activates HADHA. This simple and biostable synthetic compound we named "spermimic" mirrors spermidine's ability to enhance mitochondrial bioenergetics and displays similar effectiveness in augmenting PD-1 blockade therapy in mice. This study lays the foundation for developing small-molecule activators of antitumor immunity, offering potential in combination cancer immunotherapy.

3.
Bioorg Med Chem Lett ; 110: 129856, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38914346

ABSTRACT

The discovery and development of structurally distinct lysine methyltransferase G9a inhibitors have been the subject of intense research in epigenetics. Structure-based optimization was conducted, starting with the previously reported seed compound 7a and lead to the identification of a highly potent G9a inhibitor, compound 7i (IC50 = 0.024 µM). X-ray crystallography for the ligand-protein interaction and kinetics study, along with surface plasmon resonance (SPR) analysis, revealed that compound 7i interacts with G9a in a unique binding mode. In addition, compound 7i caused attenuation of cellular H3K9me2 levels and induction of γ-globin mRNA expression in HUDEP-2 cells in a dose-dependent manner.


Subject(s)
Anemia, Sickle Cell , Enzyme Inhibitors , Epigenesis, Genetic , Histone-Lysine N-Methyltransferase , Humans , Histone-Lysine N-Methyltransferase/antagonists & inhibitors , Histone-Lysine N-Methyltransferase/metabolism , Structure-Activity Relationship , Anemia, Sickle Cell/drug therapy , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Epigenesis, Genetic/drug effects , Molecular Structure , Histocompatibility Antigens/metabolism , Dose-Response Relationship, Drug , Crystallography, X-Ray
4.
J Virol ; 98(5): e0019724, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38593321

ABSTRACT

Noroviruses are major causative agents of acute nonbacterial gastroenteritis in humans. There are neither antiviral therapeutic agents nor vaccines for noroviruses at this time. To evaluate the potential usefulness of two previously isolated human monoclonal antibody fragments, CV-1A1 and CV-2F5, we first conducted a single-particle analysis to determine the cryo-electron microscopy structure of virus-like particles (VLPs) from the genogroup I genotype 4 (GI.4) Chiba strain uniformly coated with CV-1A1 fragments. The results revealed that the GI.4-specific CV-1A1 antibody bound to the P2 subdomain, in which amino acids are less conserved and variable. Interestingly, a part of the CV-1A1 intrudes into the histo-blood group antigen-binding site, suggesting that this antibody might exert neutralizing activity. Next, we determined the crystal structure of the protruding (P) domain of the capsid protein in the complex form with the CV-2F5 antibody fragment. Consistent with the cross-reactivity, the CV-2F5 bound to the P1 subdomain, which is rich in amino acids conserved among the GI strains, and moreover induced a disruption of Chiba VLPs. These results suggest that the broadly reactive CV-2F5 antibody can be used as both a universal detection reagent and an antiviral drug for GI noroviruses. IMPORTANCE: We conducted the structural analyses of the VP1 protein from the GI.4 Chiba norovirus to identify the binding sites of the previously isolated human monoclonal antibodies CV-1A1 and CV-2F5. The cryo-electron microscopy of the Chiba virus-like particles (VLPs) complexed with the Fv-clasp forms of GI.4-specific CV-1A1 revealed that this antibody binds to the highly variable P2 subdomain, suggesting that this antibody may have neutralizing ability against the GI.4 strains. X-ray crystallography revealed that the CV-2F5 antibody bound to the P1 subdomain, which is rich in conserved amino acids. This result is consistent with the ability of the CV-2F5 antibody to react with a wide variety of GI norovirus strains. It is also found that the CV-2F5 antibody caused a disruption of VLPs. Our findings, together with previous reports on the structures of VP1 proteins and VLPs, are expected to open a path for the structure-based development of antivirals and vaccines against norovirus disease.


Subject(s)
Antibodies, Monoclonal , Antibodies, Viral , Norovirus , Humans , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Binding Sites , Capsid Proteins/immunology , Capsid Proteins/chemistry , Capsid Proteins/metabolism , Cryoelectron Microscopy/methods , Crystallography, X-Ray , Models, Molecular , Norovirus/immunology
5.
Carbohydr Polym ; 332: 121907, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38431393

ABSTRACT

Low-concentration alkali treatments at low temperatures facilitate the crystal transition of cellulose I to II. However, the transition mechanism remains unclear. Hence, in this study, we traced the transition using in situ solid-state 13C CP/MAS NMR, WAXS, and 23Na NMR relaxation measurements. In situ solid-state 13C CP/MAS NMR and WAXS measurements revealed that soaking cellulose in NaOH at low temperatures disrupts the intramolecular hydrogen bonds and lowers the crystallinity of cellulose. The dynamics of Na ions (NaOH) play a crucial role in causing these phenomena. 23Na NMR relaxation measurements indicated that the Na-ion correlation time becomes longer during the crystal transition. This transition requires the penetration of Na ions (NaOH) into the cellulose crystal and a reduction in Na-ion mobility, which occurs at low temperatures or high NaOH concentrations. The interactions between cellulose and NaOH disrupt intramolecular hydrogen bonds, inducing a conformational change in the cellulose molecules into a more stable arrangement. This weakens the hydrophobic interactions of cellulose, and facilitates the penetration of NaOH and water into the crystal, leading to the formation of alkali cellulose. Our findings suggest that a strategy to control NaOH dynamics could lead to the discovery of a novel preparation method for cellulose II.

6.
Polymers (Basel) ; 15(24)2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38139932

ABSTRACT

The group-transfer polymerization (GTP) of N,N-bis(2-methoxyethyl)acrylamide (MOEAm) initiated by Me2EtSiH in the hydrosilylation-promoted method and by silylketene acetal (SKA) in the conventional method proceeded in a controlled/living manner to provide poly(N,N-bis(2-methoxyethyl)acrylamide) (PMOEAm) and PMOEAm with the SKA residue at the α-chain end (MCIP-PMOEAm), respectively. PMOEAm-b-poly(N,N-dimethylacrylamide) (PDMAm) and PMOEAm-s-PDMAm and PMOEAm-b-poly(N,N-bis(2-ethoxyethyl)acrylamide) (PEOEAm) and PMOEAm-s-PEOEAm were synthesized by the block and random group-transfer copolymerization of MOEAm and N,N-dimethylacrylamide or N,N-bis(2-ethoxyethyl)acrylamide. The homo- and copolymer structures affected the thermoresponsive properties; the cloud point temperature (Tcp) increasing by decreasing the degree of polymerization (x). The chain-end group in PMOEAm affected the Tcp with PMOEAmx > MCIP-PMOEAmx. The Tcp of statistical copolymers was higher than that of block copolymers, with PMOEAmx-s-PDMAmy > PMOEAmx-b-PDMAmy and PMOEAmx-s-PEOEAmy > PMOEAmx-b-PEOEAmy.

7.
Nat Commun ; 14(1): 4103, 2023 07 17.
Article in English | MEDLINE | ID: mdl-37460559

ABSTRACT

Histone acetylation is important for the activation of gene transcription but little is known about its direct read/write mechanisms. Here, we report cryogenic electron microscopy structures in which a p300/CREB-binding protein (CBP) multidomain monomer recognizes histone H4 N-terminal tail (NT) acetylation (ac) in a nucleosome and acetylates non-H4 histone NTs within the same nucleosome. p300/CBP not only recognized H4NTac via the bromodomain pocket responsible for reading, but also interacted with the DNA minor grooves via the outside of that pocket. This directed the catalytic center of p300/CBP to one of the non-H4 histone NTs. The primary target that p300 writes by reading H4NTac was H2BNT, and H2BNTac promoted H2A-H2B dissociation from the nucleosome. We propose a model in which p300/CBP replicates histone N-terminal tail acetylation within the H3-H4 tetramer to inherit epigenetic storage, and transcribes it from the H3-H4 tetramer to the H2B-H2A dimers to activate context-dependent gene transcription through local nucleosome destabilization.


Subject(s)
Histones , Nucleosomes , Histones/metabolism , CREB-Binding Protein/genetics , Acetylation , Epigenesis, Genetic , p300-CBP Transcription Factors/genetics , p300-CBP Transcription Factors/metabolism
9.
J Med Chem ; 66(6): 4059-4085, 2023 03 23.
Article in English | MEDLINE | ID: mdl-36882960

ABSTRACT

Identification of structurally novel inhibitors of lysine methyltransferase G9a has been a subject of intense research in cancer epigenetics. Starting with the high-throughput screening (HTS) hit rac-10a obtained from the chemical library of the University of Tokyo Drug Discovery Initiative, the structure-activity relationship of the unique substrate-competitive inhibitors was established with the help of X-ray crystallography and fragment molecular orbital (FMO) calculations for the ligand-protein interaction. Further optimization of the in vitro characteristics and drug metabolism and pharmacokinetics (DMPK) properties led to the identification of 26j (RK-701), which is a structurally distinct potent inhibitor of G9a/GLP (IC50 = 27/53 nM). Compound 26j exhibited remarkable selectivity against other related methyltransferases, dose-dependent attenuation of cellular H3K9me2 levels, and tumor growth inhibition in MOLT-4 cells in vitro. Moreover, compound 26j showed inhibition of tumor initiation and growth in a carcinogen-induced hepatocellular carcinoma (HCC) in vivo mouse model without overt acute toxicity.


Subject(s)
Antineoplastic Agents , Carcinoma, Hepatocellular , Liver Neoplasms , Animals , Mice , Antineoplastic Agents/pharmacology , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Histone-Lysine N-Methyltransferase , Lysine
10.
Birth Defects Res ; 115(7): 674-686, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36811147

ABSTRACT

BACKGROUND: A high-fructose diet causes the progression of chronic kidney disease. Maternal malnutrition during pregnancy and lactation increases oxidative stress, leading to chronic renal diseases later in life. We investigated whether curcumin intake during lactation could suppress oxidative stress and regulate NF-E2-related factor 2 (Nrf2) expression in the kidneys of fructose-loaded female rat offspring exposed to maternal protein restriction. METHODS: Pregnant Wistar rats received diets containing 20% (NP) or 8% (LP) casein and 0 or 2.5 g "highly absorptive curcumin" /kg diet containing-LP diets (LP/LP or LP/Cur) during lactation. At weaning, female offspring received either distilled water (W) or 10% fructose solution (Fr) and were divided into four groups: NP/NP/W, LP/LP/W, LP/LP/Fr, and LP/Cur/Fr. At week 13, glucose (Glc), triacylglycerol (Tg), and malondialdehyde (MDA) levels in the plasma, macrophages number, fibrotic area, glutathione (GSH) levels, glutathione peroxidase (GPx) activity, protein expression levels of Nrf2, heme oxygenase-1 (HO-1), and superoxide dismutase 1 (SOD1) in the kidneys were examined. RESULTS: The plasma levels of Glc, TG, and MDA, the number of macrophages, and the percentage of fibrotic area in the kidneys of the LP/Cur/Fr group were significantly lower than those of the LP/LP/Fr group. The expression of Nrf2 and its downstream molecules HO-1 and SOD1, GSH levels, and GPx activity in the kidneys of the LP/Cur/Fr group were significantly higher than those of the LP/LP/Fr group. CONCLUSIONS: Maternal curcumin intake during lactation may suppress oxidative stress by upregulating Nrf2 expression in the kidneys of fructose-loaded female offspring exposed to maternal protein restriction.


Subject(s)
Curcumin , Pregnancy , Rats , Animals , Female , Rats, Wistar , Curcumin/pharmacology , Curcumin/metabolism , Up-Regulation , Diet, Protein-Restricted/adverse effects , Fructose/adverse effects , Superoxide Dismutase-1/metabolism , NF-E2-Related Factor 2/metabolism , Kidney/metabolism , Lactation , Oxidative Stress , Antioxidants/pharmacology , Antioxidants/metabolism
11.
Polymers (Basel) ; 15(3)2023 Jan 28.
Article in English | MEDLINE | ID: mdl-36771966

ABSTRACT

The redox behaviors of macrocyclic molecules with an entirely π-conjugated system are of interest due to their unique optical, electronic, and magnetic properties. In this study, defect-free cyclic P3HT with a degree of polymerization (DPn) from 14 to 43 was synthesized based on our previously established method, and its unique redox behaviors arising from the cyclic topology were investigated. Cyclic voltammetry (CV) showed that the HOMO level of cyclic P3HT decreases from -4.86 eV (14 mer) to -4.89 eV (43 mer), in contrast to the linear counterparts increasing from -4.94 eV (14 mer) to -4.91 eV (43 mer). During the CV measurement, linear P3HT suffered from electro-oxidation at the chain ends, while cyclic P3HT was stable. ESR and UV-Vis-NIR spectroscopy suggested that cyclic P3HT has stronger dicationic properties due to the interactions between the polarons. On the other hand, linear P3HT showed characteristics of polaron pairs with multiple isolated polarons. Moreover, the dicationic properties of cyclic P3HT were more pronounced for the smaller macrocycles.

12.
Nat Commun ; 14(1): 23, 2023 01 12.
Article in English | MEDLINE | ID: mdl-36635268

ABSTRACT

Sickle cell disease (SCD) is a heritable disorder caused by ß-globin gene mutations. Induction of fetal γ-globin is an established therapeutic strategy. Recently, epigenetic modulators, including G9a inhibitors, have been proposed as therapeutic agents. However, the molecular mechanisms whereby these small molecules reactivate γ-globin remain unclear. Here we report the development of a highly selective and non-genotoxic G9a inhibitor, RK-701. RK-701 treatment induces fetal globin expression both in human erythroid cells and in mice. Using RK-701, we find that BGLT3 long non-coding RNA plays an essential role in γ-globin induction. RK-701 selectively upregulates BGLT3 by inhibiting the recruitment of two major γ-globin repressors in complex with G9a onto the BGLT3 gene locus through CHD4, a component of the NuRD complex. Remarkably, BGLT3 is indispensable for γ-globin induction by not only RK-701 but also hydroxyurea and other inducers. The universal role of BGLT3 in γ-globin induction suggests its importance in SCD treatment.


Subject(s)
Anemia, Sickle Cell , RNA, Long Noncoding , Mice , Humans , Animals , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , gamma-Globins/genetics , Erythroid Cells/metabolism , Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/metabolism , Gene Expression , Fetal Hemoglobin/genetics , Fetal Hemoglobin/metabolism
13.
Neurol Med Chir (Tokyo) ; 63(2): 73-79, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36599429

ABSTRACT

Mechanical thrombectomy (MT) is the standard treatment for acute large occlusion of the cerebral artery. Evidence for the success of this procedure was based on the treatment of patients with internal carotid artery and middle cerebral artery thrombi. There are a few reports on thrombi extending to the common carotid artery (CCA). We document our endovascular procedure and the clinical outcome in seven consecutive patients who underwent MT for CCA thrombi between September 2016 and April 2021. Their mean National Institutes of Health Stroke Scale score was 20.0 (range, 9-30), and the mean diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score on magnetic resonance images was 8.7 (range, 7-10). In six patients, MT of the CCA occlusion was successful, and the mean puncture-to-reperfusion time was 84 minutes (range, 39-211 minutes). In five patients, successful reperfusion was obtained. The mean total pass number was 4.1 (range, 2-7). Due to large thrombi, we performed balloon guide catheter (BGC) occlusion in three patients. Sheath occlusion occurred in two, and thrombus migration into the femoral artery around the sheath was observed in two patients. The mean modified Rankin Scale score 3 months post-stroke was 3.6 (range, 2-5). When the removal of a large CCA thrombus is attempted in a single step, catheter and sheath occlusion may occur, and this increases the risk for critical systemic artery occlusion. Therefore, we suggest that MT be combined with the BGC technique and propose the use of a large aspiration catheter to decrease the volume of the thrombus.


Subject(s)
Arterial Occlusive Diseases , Brain Ischemia , Carotid Artery Diseases , Endovascular Procedures , Stroke , Thrombosis , Humans , Thrombectomy/methods , Treatment Outcome , Retrospective Studies , Carotid Artery, Common/diagnostic imaging , Carotid Artery, Common/surgery , Endovascular Procedures/methods , Stents , Brain Ischemia/diagnostic imaging , Brain Ischemia/etiology , Brain Ischemia/surgery
14.
Sci Rep ; 12(1): 21208, 2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36481806

ABSTRACT

Lanthanoid-doped Gallium Nitride (GaN) integrated into nanophotonic technologies is a promising candidate for room-temperature quantum photon sources for quantum technology applications. We manufactured praseodymium (Pr)-doped GaN nanopillars of varying size, and showed significantly enhanced room-temperature photon extraction efficiency compared to unstructured Pr-doped GaN. Implanted Pr ions in GaN show two main emission peaks at 650.3 nm and 651.8 nm which are attributed to 3P0-3F2 transition in the 4f-shell. The maximum observed enhancement ratio was 23.5 for 200 nm diameter circular pillars, which can be divided into the emitted photon extraction enhancement by a factor of 4.5 and the photon collection enhancement by a factor of 5.2. The enhancement mechanism is explained by the eigenmode resonance inside the nanopillar. Our study provides a pathway for Lanthanoid-doped GaN nano/micro-scale photon emitters and quantum technology applications.

15.
VideoGIE ; 7(11): 401-403, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36407041

ABSTRACT

Video 1Crush the large-sized stones directly using an electrohydraulic lithotripsy device.

16.
Polymers (Basel) ; 14(21)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36365529

ABSTRACT

Silver nanoparticles (AgNPs) are used in a wide range of applications, and the size control and stability of the nanoparticles are crucial aspects in their applications. In the present study, cyclized poly(ethylene glycol) (c-PEG) with various molecular weights, along with linear PEG with hydroxy chain ends (HO-PEG-OH) and methoxy chain ends (MeO-PEG-OMe) were applied for the Tollens' synthesis of AgNPs. The particle size was significantly affected by the topology and end groups of PEG. For example, the size determined by TEM was 40 ± 7 nm for HO-PEG5k-OH, 21 ± 4 nm for c-PEG5k, and 48 ± 9 nm for MeO-PEG5k-OMe when the molar ratio of PEG to AgNO3 (ω) was 44. The stability of AgNPs was also drastically improved by cyclization; the relative UV-Vis absorption intensity (A/A0 × 100%) at λmax to determine the proportion of persisting AgNPs in an aqueous NaCl solution (37.5 mM) was 58% for HO-PEG5k-OH, 80% for c-PEG5k, and 40% for MeO-PEG5k-OMe, despite the fact that AgNPs with c-PEG5k were much smaller than those with HO-PEG5k-OH and MeO-PEG5k-OMe.

17.
J Am Chem Soc ; 144(44): 20171-20176, 2022 11 09.
Article in English | MEDLINE | ID: mdl-36306265

ABSTRACT

Visible light, particularly in the blue region of the spectrum, can cause cell dysfunction through the generation of singlet oxygen, contributing to cellular aging and age-related pathologies. Although photooxidation of nucleic acids, lipids, and amino acids has been extensively studied, the magnitude and span of blue-light-induced protein damages within proteome remain largely unknown. Herein we present a chemoproteomic approach to mapping blue-light-damaged proteins in live mammalian cells by exploiting a nucleophilic alkyne chemical probe. A gene ontology enrichment analysis revealed that cell surface proteins are more readily oxidized than other susceptible sets of proteins, including mitochondrial proteins. In particular, the integrin family of cell surface receptors (ITGs) was highly ranked in the mammalian cells tested, including human corneal endothelial cells. The blue-light-oxidized ITGB1 protein was functionally inactive in promoting cell adhesion and proliferation, suggesting that the photodamage of integrins contributes to the blue-light-induced cell dysfunction. Further application of our method to various cells and tissues should lead to a comprehensive analysis of light-sensitive proteins.


Subject(s)
Endothelial Cells , Singlet Oxygen , Animals , Humans , Oxidation-Reduction , Light , Mammals
18.
Cancer Sci ; 113(10): 3608-3617, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36068652

ABSTRACT

To overcome the increasing burden on pathologists in diagnosing gastric biopsies, we developed an artificial intelligence-based system for the pathological diagnosis of gastric biopsies (AI-G), which is expected to work well in daily clinical practice in multiple institutes. The multistage semantic segmentation for pathology (MSP) method utilizes the distribution of feature values extracted from patches of whole-slide images (WSI) like pathologists' "low-power view" information of microscopy. The training dataset included WSIs of 4511 gastric biopsy tissues from 984 patients. In tissue-level validation, MSP AI-G showed better accuracy (91.0%) than that of conventional patch-based AI-G (PB AI-G) (89.8%). Importantly, MSP AI-G unanimously achieved higher accuracy rates (0.946 ± 0.023) than PB AI-G (0.861 ± 0.078) in tissue-level analysis, when applied to the cohorts of 10 different institutes (3450 samples of 1772 patients in all institutes, 198-555 samples of 143-206 patients in each institute). MSP AI-G had high diagnostic accuracy and robustness in multi-institutions. When pathologists selectively review specimens in which pathologist's diagnosis and AI prediction are discordant, the requirement of a secondary review process is significantly less compared with reviewing all specimens by another pathologist.


Subject(s)
Artificial Intelligence , Stomach , Biopsy , Humans
19.
Nanoscale Adv ; 4(2): 532-545, 2022 Jan 18.
Article in English | MEDLINE | ID: mdl-36132700

ABSTRACT

Silver nanoparticles (AgNPs) are practically valuable in biological applications. However, no steady PEGylation has been established, which is essential for internal use in humans or animals. In this study, cyclic PEG (c-PEG) without any chemical inhomogeneity is physisorbed onto AgNPs to successfully PEGylate and drastically enhance the dispersion stability against physiological conditions, white light, and high temperature. In contrast, linear HO-PEG-OH and MeO-PEG-OMe do not confer stability to AgNPs, and HS-PEG-OMe, which is often used for gold nanoparticles, sulfidates the surface to considerably degrade the properties. TEM shows an essentially intact nanostructure of c-PEG-physisorbed AgNPs even after heating at 95 °C, while complete disturbance is observed for other AgNPs. Molecular weight- and concentration-dependent stabilization by c-PEG is investigated, and DLS and ζ-potential measurements prove the formation of a c-PEG layer on the surface of AgNPs. Furthermore, c-PEG-physisorbed AgNPs exhibit persistent antimicrobial activity and cytotoxicity.

20.
Neurol Int ; 14(3): 738-747, 2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36135997

ABSTRACT

BACKGROUND: Recently, it was reported that the extent of cortico-cortical functional connections can be estimated by the correlation coefficient based on electroencephalography (EEG) monitoring. We aimed to investigate whether the EEG correlation coefficient change with motor task activation can predict the functional outcomes of hemiparetic stroke patients. METHODS: Sixteen post-stroke hemiparetic patients admitted to our rehabilitation ward were studied. On admission, EEG recording to calculate the correlation coefficient was performed at rest and during motor task activation. For the analysis of the EEG data, the program software FOCUS (NIHON KOHDEN, Japan) was used. The motor function of paretic limbs was evaluated with the Fugl-Meyer Assessment (FMA) on admission and 4 weeks after admission. RESULTS: Significant increases in the correlation coefficient with motor task activation were noted in C3-F3 or C4-F4, C3-F7 or C4-F8, and F3-F7 or F4-F8 of the lesional hemisphere. Among them, the rate of the correlation coefficient change in F3-F7 or F4-F8 in the lesional hemisphere was significantly correlated with the rate of the upper-limb FMA score change. CONCLUSION: The extent of the EEG correlation coefficient change with motor task activation in F3-F7 or F4-F8 of the lesional hemisphere may help predict the motor functional outcomes of hemiparetic upper limbs after stroke.

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