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1.
Nucleic Acids Res ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38950903

ABSTRACT

In higher eukaryotes, tRNA methyltransferase 10A (TRMT10A) is responsible for N1-methylguanosine modification at position nine of various cytoplasmic tRNAs. Pathogenic mutations in TRMT10A cause intellectual disability, microcephaly, diabetes, and short stature in humans, and generate cytotoxic tRNA fragments in cultured cells; however, it is not clear how TRMT10A supports codon translation or brain functions. Here, we generated Trmt10a null mice and showed that tRNAGln(CUG) and initiator methionine tRNA levels were universally decreased in various tissues; the same was true in a human cell line lacking TRMT10A. Ribosome profiling of mouse brain revealed that dysfunction of TRMT10A causes ribosome slowdown at the Gln(CAG) codon and increases translation of Atf4 due to higher frequency of leaky scanning of its upstream open reading frames. Broadly speaking, translation of a subset of mRNAs, especially those for neuronal structures, is perturbed in the mutant brain. Despite not showing discernable defects in the pancreas, liver, or kidney, Trmt10a null mice showed lower body weight and smaller hippocampal postsynaptic densities, which is associated with defective synaptic plasticity and memory. Taken together, our study provides mechanistic insight into the roles of TRMT10A in the brain, and exemplifies the importance of universal tRNA modification during translation of specific codons.

2.
Nat Metab ; 4(2): 180-189, 2022 02.
Article in English | MEDLINE | ID: mdl-35228746

ABSTRACT

Adult skeletal muscle is a highly plastic tissue that readily reduces or gains its mass in response to mechanical and metabolic stimulation; however, the upstream mechanisms that control muscle mass remain unclear. Notch signalling is highly conserved, and regulates many cellular events, including proliferation and differentiation of various types of tissue stem cell via cell-cell contact. Here we reveal that multinucleated myofibres express Notch2, which plays a crucial role in disuse- or diabetes-induced muscle atrophy. Mechanistically, in both atrophic conditions, the microvascular endothelium upregulates and releases the Notch ligand, Dll4, which then activates muscular Notch2 without direct cell-cell contact. Inhibition of the Dll4-Notch2 axis substantively prevents these muscle atrophy and promotes mechanical overloading-induced muscle hypertrophy in mice. Our results illuminate a tissue-specific function of the endothelium in controlling tissue plasticity and highlight the endothelial Dll4-muscular Notch2 axis as a central upstream mechanism that regulates catabolic signals from mechanical and metabolic stimulation, providing a therapeutic target for muscle-wasting diseases.


Subject(s)
Adaptor Proteins, Signal Transducing , Calcium-Binding Proteins , Muscular Atrophy , Animals , Endothelium , Mice , Muscle, Skeletal , Receptor, Notch2
4.
ACS Appl Nano Mater ; 4(11): 11881-11887, 2021 Nov 26.
Article in English | MEDLINE | ID: mdl-37556290

ABSTRACT

The rapid transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-driven infection signifies an ultimate challenge to global health, and the development of effective strategies for preventing and/or mitigating its effects are of the utmost importance. In the current study, an in-depth investigation for the understanding of the SARS-CoV-2 inactivation route using graphene oxide (GO) is presented. We focus on the antiviral effect of GO nanosheets on three SARS-CoV-2 strains: Wuhan, B.1.1.7 (U.K. variant), and P.1 (Brazilian variant). Plaque assay and real-time reverse transcription-polymerase chain reaction (RT-PCR) showed that 50 and 98% of the virus in a supernatant could be cleared following incubation with GO (100 µg/mL) for 1 and 60 min, respectively. Transmission electron microscopy (TEM) analysis and protein (spike (S) and nucleocapsid (N) proteins) decomposition evaluation confirm a two-step virus inactivation mechanism that includes (i) adsorption of the positively charged spike of SARS-CoV-2 on the negatively charged GO surface and (ii) neutralization/inactivation of the SARS-CoV-2 on the surface of GO through decomposition of the viral protein. As the interaction of S protein with human angiotensin-converting enzyme 2 (ACE2) is required for SARS-CoV-2 to enter into human cells, the damage to the S protein using GO makes it a potential candidate for use in contributing to the inhibition of the worldwide spread of SARS-CoV-2. Specifically, our findings provide the potential for the construction of an effective anti-SARS-CoV-2 face mask using a GO nanosheet, which could contribute greatly to preventing the spread of the virus. In addition, as the effect of surface contamination can be severe in the spreading of SARS-CoV-2, the development of efficient anti-SARS-CoV-2 protective surfaces/coatings based on GO nanosheets could play a significant role in controlling the spread of the virus through the utilization of GO-based nonwoven cloths, filters, and so on.

5.
PLoS One ; 13(12): e0209096, 2018.
Article in English | MEDLINE | ID: mdl-30557369

ABSTRACT

Genome-wide association studies (GWAS) have identified greater than 30 variants associated with ovarian cancer, but most of these variants were investigated in European populations. Here, we integrated GWAS and subsequent functional analyses to identify the genetic variants with potential regulatory effects. We conducted GWAS for ovarian cancer using 681 Japanese cases and 17,492 controls and found that rs137672 on 22q13.1 exhibited a strong association with a P-value of 1.05 × 10(-7) and an odds ratio of 0.573 with a 95% confidence interval of 0.466-0.703. In addition, three previously reported SNPs, i.e., rs10088218, rs9870207 and rs1400482, were validated in the Japanese population (P < 0.05) with the same risk allele as noted in previous studies. Functional studies including regulatory feature analysis and electrophoretic mobility shift assay (EMSA) revealed two regulatory SNPs in 22q13.1, rs2072872 and rs6509, that affect the binding affinity to some nuclear proteins in ovarian cancer cells. The plausible regulatory proteins whose motifs could be affected by the allele changes of these two SNPs were also proposed. Moreover, the protective G allele of rs6509 was associated with a decreased SYNGR1 expression level in normal ovarian tissues. Our findings elucidated the regulatory variants in 22q13.1 that are associated with ovarian cancer risk.


Subject(s)
Chromosomes, Human, Pair 22/genetics , Genetic Variation , Genome-Wide Association Study , Ovarian Neoplasms/genetics , Aged , Alleles , Case-Control Studies , Female , Genotyping Techniques , Humans , Japan , Middle Aged , Polymorphism, Single Nucleotide
6.
Int J Oncol ; 51(2): 724-736, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28714518

ABSTRACT

p53, one of the most frequently mutated genes in colon cancer, suppresses cancer development through transactivation of its targets. Herein, we conducted a comprehensive analysis of the p53 downstream pathway in colorectal cancer by using multi-omics analysis. Mass spectrometric analysis of HCT116 p53+/+ and HCT116 p53-/- cells treated with adriamycin identified 124 proteins increased by DNA damage in a p53-dependent manner. Further screening using a cDNA microarray and the TCGA database revealed MICALL1 as a novel p53 target, and we identified functional p53 binding motifs located approximately 3000 base pairs upstream of the MICALL1 gene. MICALL1 expression was significantly decreased in colorectal cancer tissues with p53 mutation compared with those without p53 mutation. In response to DNA damage, MICALL1 co-localized with RAB8A and CD2AP at tubular recycling endosomes, whereas these proteins hardly localized at tubular recycling endosomes when p53 or MICALL1 expression was inhibited by siRNA. Our findings show that p53 regulates tubular recycling endosome biogenesis via transcriptional regulation of MICALL1, whose expression is frequently suppressed in colorectal cancer tissues.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Colorectal Neoplasms/metabolism , Cytoskeletal Proteins/genetics , Doxorubicin/pharmacology , LIM Domain Proteins/genetics , Tumor Suppressor Protein p53/genetics , Adaptor Proteins, Signal Transducing/chemistry , Adaptor Proteins, Signal Transducing/metabolism , Binding Sites , Cell Line, Tumor , Colorectal Neoplasms/genetics , Cytoskeletal Proteins/chemistry , Cytoskeletal Proteins/metabolism , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic/drug effects , HCT116 Cells , Humans , LIM Domain Proteins/chemistry , LIM Domain Proteins/metabolism , Mass Spectrometry , Microfilament Proteins , Mixed Function Oxygenases , Mutation , Oligonucleotide Array Sequence Analysis/methods , Proteomics/methods , Signal Transduction/drug effects , rab GTP-Binding Proteins/metabolism
7.
Int J Med Inform ; 85(1): 76-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26520235

ABSTRACT

INTRODUCTION: EGMAIN-GX is the computerized physician order entry system used in Japan. The automatic rounding-off of the calculated dose of chemotherapeutic drugs is an update in version 4, compared to version 2. We conducted a comparative study between EGMAIN-GX versions 2 and 4 to estimate the effect of the automatic rounding-off function on ordering time and dose dispersion. METHODS: Twelve hematologists ordered 5 predefined chemotherapeutic regimens most commonly used in treating hematologic malignancies, twice for each regimen. RESULTS: EGMAIN-GX version 4 significantly reduced ordering times compared to version 2 (635s vs. 259s, p<0.01). EGMAIN-GX version 4 also yielded a significantly higher ratio of actual to ideal doses of chemotherapeutic drugs than did version 2 (1.0097 and 0.9997, respectively; p<0.01) and a lower standard deviation (0.0275 and 0.0290, respectively). CONCLUSIONS: The automatic rounding-off function could decrease the ordering time and dose dispersion of chemotherapeutic drugs.


Subject(s)
Antineoplastic Agents/therapeutic use , Automation , Hematologic Neoplasms/drug therapy , Medical Order Entry Systems , Antineoplastic Agents/administration & dosage , Humans
8.
Pathol Oncol Res ; 21(4): 1037-43, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25837848

ABSTRACT

To clarify the clinical impact of prior use of azacitidine (AZA) on outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for myelodysplastic syndrome (MDS), we retrospectively reviewed the clinical outcomes of 15 MDS patients who were treated with AZA before allo-HSCT (AZA group). We compared the outcomes of these 15 patients with 52 MDS patients who were solely given the best supportive care (BSC) before allo-HSCT (BSC group). Although patients in the AZA group were older with higher International Prognostic Scoring System (IPSS) scores compared to patients in the BSC group, no significant differences were found between the two groups in overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR) or non-relapse mortality. However, in patients with a higher IPSS score (Int-2/High), pre-transplant AZA may provide better OS and DFS and lower CIR. Acute graft-versus-host disease rates were similar between the two groups. These results should be reassuring to patients with high-risk MDS receiving AZA before allo-HSCT.


Subject(s)
Azacitidine/therapeutic use , Enzyme Inhibitors/therapeutic use , Myelodysplastic Syndromes/surgery , Myelodysplastic Syndromes/therapy , Adolescent , Adult , Aged , Disease-Free Survival , Female , Hematopoietic Stem Cell Transplantation/methods , Humans , Male , Middle Aged , Recurrence , Retrospective Studies , Transplantation Conditioning/methods , Transplantation, Homologous/methods , Young Adult
17.
Allergy Asthma Proc ; 31(5): 422-7, 2010.
Article in English | MEDLINE | ID: mdl-20929610

ABSTRACT

Accurate and detailed pollen monitoring is useful for selection of medication and for allergen avoidance in patients with allergic rhinitis. Burkard and Durham pollen samplers are commonly used, but are labor and time intensive. In contrast, automatic pollen counters allow simple real-time pollen counting; however, these instruments have difficulty in distinguishing pollen from small nonpollen airborne particles. Misidentification and underestimation rates for an automatic pollen counter were examined to improve the accuracy of the pollen count. The characteristics of the automatic pollen counter were determined in a chamber study with exposure to cedar pollens or soil grains. The cedar pollen counts were monitored in 2006 and 2007, and compared with those from a Durham sampler. The pollen counts from the automatic counter showed a good correlation (r > 0.7) with those from the Durham sampler when pollen dispersal was high, but a poor correlation (r < 0.5) when pollen dispersal was low. The new correction method, which took into account the misidentification and underestimation, improved this correlation to r > 0.7 during the pollen season. The accuracy of automatic pollen counting can be improved using a correction to include rates of underestimation and misidentification in a particular geographical area.


Subject(s)
Air Pollutants/analysis , Allergens/analysis , Cedrus , Environmental Monitoring/methods , Pollen , Environmental Monitoring/instrumentation , Humans , Japan , Particle Size , Reproducibility of Results , Sensitivity and Specificity , Software , Soil/analysis
18.
Org Lett ; 8(9): 1843-5, 2006 Apr 27.
Article in English | MEDLINE | ID: mdl-16623565

ABSTRACT

[reaction: see text] A novel and efficient procedure for the generation of the reactive indole-2,3-quinodimethane intermediates from the allenylanilines is described. The indole-2,3-quinodimethane intermediates were captured by several dienophiles to afford the corresponding tetrahydro- and dihydrocarbazole derivatives. This method is significantly different from the previously reported ones, which involve the 1,4-elimination or its related reactions of the indole derivatives that possess suitable substituents at both the C-2 and C-3 positions.


Subject(s)
Indoles/chemical synthesis , Methane/analogs & derivatives , Methane/chemical synthesis , Aniline Compounds/chemistry , Catalysis , Indoles/chemistry , Methane/chemistry , Molecular Structure
19.
Org Lett ; 7(26): 5793-6, 2005 Dec 22.
Article in English | MEDLINE | ID: mdl-16354068

ABSTRACT

[reaction: see text] The Stille coupling of N-acyl-2-iodoanilines with the 1-(tributylstannyl)-1-substituted allenes affected the successive one-step formation of the 2-methyl-3-substituted indoles. Alternatively, the other type of 2-alkyl-3-substituted indoles could be synthesized in a one-pot operation, which consists of the Stille coupling reaction with the 1-(tributylstannyl)-1,3-disubstituted allenes, followed by TBAF treatment. This procedure could be applied to the synthesis of indomethacin.


Subject(s)
Alkenes/chemistry , Combinatorial Chemistry Techniques , Indoles/chemistry , Indoles/chemical synthesis , Indole Alkaloids/chemical synthesis , Indomethacin/chemical synthesis , Molecular Structure
20.
J Org Chem ; 69(6): 2128-36, 2004 Mar 19.
Article in English | MEDLINE | ID: mdl-15058962

ABSTRACT

A new procedure for constructing monocyclic five- and six-membered azacycles by the endo-mode ring-closing reaction of allenylazido derivatives under neutral conditions has been developed. The azabicyclo[m.n.0] compounds were prepared by applying this newly developed procedure. The seven-membered azacycle was prepared when the allene possessing an unsubstituted carboxyl amido functionality was submitted to the basic conditions. In addition, indole and quinoline skeletons were synthesized using this procedure.


Subject(s)
Alkadienes/chemistry , Aza Compounds/chemical synthesis , Bridged Bicyclo Compounds/chemical synthesis , Alkynes/chemistry , Amides/chemistry , Amination , Catalysis , Cyclization , Heterocyclic Compounds/chemical synthesis , Indoles/chemical synthesis , Indoles/chemistry , Oxidation-Reduction , Propanols/chemistry , Quinolines/chemical synthesis , Quinolines/chemistry , Stereoisomerism , Trialkyltin Compounds
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