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1.
JMIR Med Inform ; 8(4): e16970, 2020 Apr 22.
Article in English | MEDLINE | ID: mdl-32319959

ABSTRACT

BACKGROUND: Falls in hospitals are the most common risk factor that affects the safety of inpatients and can result in severe harm. Therefore, preventing falls is one of the most important areas of risk management for health care organizations. However, existing methods for predicting falls are laborious and costly. OBJECTIVE: The objective of this study is to verify whether hospital inpatient falls can be predicted through the analysis of a single input-unstructured nursing records obtained from Japanese electronic medical records (EMRs)-using a natural language processing (NLP) algorithm and machine learning. METHODS: The nursing records of 335 fallers and 408 nonfallers for a 12-month period were extracted from the EMRs of an acute care hospital and randomly divided into a learning data set and test data set. The former data set was subjected to NLP and machine learning to extract morphemes that contributed to separating fallers from nonfallers to construct a model for predicting falls. Then, the latter data set was used to determine the predictive value of the model using receiver operating characteristic (ROC) analysis. RESULTS: The prediction of falls using the test data set showed high accuracy, with an area under the ROC curve, sensitivity, specificity, and odds ratio of mean 0.834 (SD 0.005), mean 0.769 (SD 0.013), mean 0.785 (SD 0.020), and mean 12.27 (SD 1.11) for five independent experiments, respectively. The morphemes incorporated into the final model included many words closely related to known risk factors for falls, such as the use of psychotropic drugs, state of consciousness, and mobility, thereby demonstrating that an NLP algorithm combined with machine learning can effectively extract risk factors for falls from nursing records. CONCLUSIONS: We successfully established that falls among hospital inpatients can be predicted by analyzing nursing records using an NLP algorithm and machine learning. Therefore, it may be possible to develop a fall risk monitoring system that analyzes nursing records daily and alerts health care professionals when the fall risk of an inpatient is increased.

2.
Biomarkers ; 22(3-4): 253-260, 2017.
Article in English | MEDLINE | ID: mdl-27321284

ABSTRACT

Our study measured circulating microRNA (miRNA) levels in the plasma of calsequestrin (CSQ)-tg mouse, a severe heart failure model, and evaluated whether treatment with angiotensin II type 1 receptor blocker, azilsartan medoxomil (AZL-M) influenced their levels using miRNA array analysis. MiR-146a, miR-149, miR-150, and miR-342-3p were reproducibly reduced in the plasma of CSQ-tg mice. Among them, miR-146a and miR-342-3p were significantly restored by AZL-M, which were associated with improvement of survival rate and reduction of congestion. These results suggest that miRNA, especially miR-146a and miR-342-3p, could be used as potential biomarkers for evaluating the efficacy of anti-heart failure drugs.


Subject(s)
Benzimidazoles/pharmacology , Heart Failure/drug therapy , MicroRNAs/blood , Oxadiazoles/pharmacology , Angiotensin II Type 1 Receptor Blockers/pharmacology , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Animals , Benzimidazoles/therapeutic use , Calsequestrin , Cardiomyopathy, Dilated/drug therapy , Disease Models, Animal , Heart Failure/genetics , Mice , Oxadiazoles/therapeutic use , Survival Rate
3.
Toxicol Sci ; 154(1): 115-125, 2016 11.
Article in English | MEDLINE | ID: mdl-27605421

ABSTRACT

Extracellular microRNAs (miRNAs) represent a promising new source of toxicity biomarkers that are sensitive indicators of site of tissue injury. In order to establish reliable approaches for use in biomarker validation studies, the HESI technical committee on genomics initiated a multi-site study to assess sources of variance associated with quantitating levels of cardiac injury induced miRNAs in biofluids using RT-qPCR. Samples were generated at a central site using a model of acute cardiac injury induced in male Wistar rats by 0.5 mg/kg isoproterenol. Biofluid samples were sent to 11 sites for measurement of 3 cardiac enriched miRNAs (miR-1-3p, miR-208a-3p, and miR-499-5p) and 1 miRNA abundant in blood (miR-16-5p) or urine (miR-192-5p) by absolute quantification using calibration curves of synthetic miRNAs. The samples included serum and plasma prepared from blood collected at 4 h, urine collected from 6 to 24 h, and plasma prepared from blood collected at 24 h post subcutaneous injection. A 3 parameter logistic model was utilized to fit the calibration curve data and estimate levels of miRNAs in biofluid samples by inverse prediction. Most sites observed increased circulating levels of miR-1-3p and miR-208a-3p at 4 and 24 h after isoproterenol treatment, with no difference seen between serum and plasma. The biological differences in miRNA levels and sample type dominated as sources of variance, along with outlying performance by a few sites. The standard protocol established in this study was successfully implemented across multiple sites and provides a benchmark method for further improvements in quantitative assays for circulating miRNAs.


Subject(s)
Heart Injuries/metabolism , MicroRNAs/blood , MicroRNAs/urine , Animals , Biomarkers/blood , Biomarkers/urine , Heart Injuries/chemically induced , Isoproterenol/toxicity , Male , Plasma/chemistry , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction , Serum/chemistry
4.
Microrna ; 5(1): 57-65, 2016.
Article in English | MEDLINE | ID: mdl-27280801

ABSTRACT

BACKGROUND: The initiation of ß-cell proliferation to recover reduced ß-cell mass is considered as one of the attractive therapeutic approaches for type 1 and 2 diabetes. In this study, we investigated the involvement of miRNAs in ß-cell proliferation. METHODS: Global miRNA array analysis of pancreas tissue was carried out using a 60% partial pancreatectomy (PPx) rodent model, which is a well-characterized model for pancreatic regeneration with accelerated proliferation of ß-cells. To explore miRNAs with mitogenic activity on ß-cells, precursors and antisense oligonucleotides (ASOs) for miRNAs were transfected into a primary islet monolayer cell cultures isolated from adult rats in order to modify their expression and proliferation of ß-cells. RESULTS: We found that miR-199b-5p, which was up-regulated 2.6 times in the pancreas of the PPx treated group, significantly enhanced the proliferation of ß-cells when its precursor was over-expressed. Target genes of miR-199b-5p were investigated and Mixed lineage kinase-3 (MLK3) was identified as one of the candidates since its expression was down-regulated through an interaction with miR-199b-5p and siRNA treatment for MLK3 enhanced the proliferation of ß-cells. CONCLUSION: Our data suggest that the up-regulation of miR-199b-5p enhances proliferation of ß-cells at least in part through down-regulation of MLK3.


Subject(s)
Cell Proliferation/genetics , Insulin-Secreting Cells/cytology , MAP Kinase Kinase Kinases/genetics , MicroRNAs/genetics , Animals , Cells, Cultured , Cyclin D1/metabolism , Cyclin E/metabolism , Diabetes Mellitus/genetics , Diabetes Mellitus/therapy , Down-Regulation/genetics , Gene Expression Regulation/genetics , MAP Kinase Kinase Kinases/biosynthesis , Male , MicroRNAs/biosynthesis , Oligonucleotides, Antisense/genetics , RNA Interference , RNA, Small Interfering/genetics , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction , Mitogen-Activated Protein Kinase Kinase Kinase 11
5.
Int J Mol Med ; 37(6): 1706-14, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27121589

ABSTRACT

Cold atmospheric pressure plasma (CAP) is known as a source of biologically active agents, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS). In the present study, we examined the effects of nitrogen (N2) on the apoptosis of and changes in gene expression in human lymphoma U937 cells exposed to argon (Ar)-CAP. Enormous amounts of hydroxyl (·OH) radicals in aqueous solution were produced using Ar­CAP generated using a 20 kHz low frequency at 18 kV with a flow rate of 2 l/min. The increase in the levels of ·OH radicals was significantly attenuated by the addition of N2 to Ar gas. On the other hand, the level of total nitrate/nitrite in the supernatant was significantly elevated in the Ar + N2-CAP­exposed U937 cells. When the cells were exposed to Ar­CAP, a significant increase in apoptosis was observed, whereas apoptosis was markedly decreased in the cells exposed to Ar + N2-CAP. Microarray and pathway analyses revealed that a newly identified gene network containing a number of heat shock proteins (HSPs), anti-apoptotic genes, was mainly associated with the biological function of the prevention of apoptosis. Quantitative PCR revealed that the expression levels of HSPs were significantly elevated in the cells exposed to Ar + N2-CAP than those exposed to Ar­CAP. These results indicate that N2 gas in Ar­CAP modifies the ratio of ROS to RNS, and suppresses the apoptosis induced by Ar­CAP. The modulation of gaseous conditions in CAP may thus prove to be useful for future clinical applications, such as for switching from a sterilizing mode to cytocidal effect for cancer cells.


Subject(s)
Apoptosis Regulatory Proteins/genetics , Gene Expression Regulation, Neoplastic/drug effects , Neoplasm Proteins/genetics , Nitrogen/pharmacology , Plasma Gases/pharmacology , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Argon/pharmacology , Atmospheric Pressure , Gene Expression Profiling , Humans , Hydroxyl Radical/metabolism , Microarray Analysis , Neoplasm Proteins/metabolism , Signal Transduction , U937 Cells
6.
Arch Biochem Biophys ; 605: 19-25, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27085689

ABSTRACT

Plasma medicine is increasingly recognized interdisciplinary field combining engineering, physics, biochemistry and life sciences. Plasma is classified into two categories based on the temperature applied, namely "thermal" and "non-thermal" (i.e., cold atmospheric plasma). Non-thermal or cold atmospheric plasma (CAP) is produced by applying high voltage electric field at low pressures and power. The chemical effects of cold atmospheric plasma in aqueous solution are attributed to high voltage discharge and gas flow, which is transported rapidly on the liquid surface. The argon-cold atmospheric plasma (Ar-CAP) induces efficient reactive oxygen species (ROS) in aqueous solutions without thermal decomposition. Their formation has been confirmed by electron paramagnetic resonance (EPR) spin trapping, which is reviewed here. The similarities and differences between the plasma chemistry, sonochemistry, and radiation chemistry are explained. Further, the evidence for free radical formation in the liquid phase and their role in the biological effects induced by cold atmospheric plasma, ultrasound and ionizing radiation are discussed.


Subject(s)
Cold Temperature , Plasma Gases/chemistry , Radiation, Ionizing , Ultrasonics , Atmospheric Pressure , Electricity , Electrochemistry , Electron Spin Resonance Spectroscopy , Free Radicals/chemistry , Helium/chemistry , Reactive Oxygen Species/chemistry , Solutions
7.
PLoS One ; 10(8): e0136956, 2015.
Article in English | MEDLINE | ID: mdl-26318000

ABSTRACT

Electron paramagnetic resonance (EPR)-spin trapping and flow cytometry were used to identify free radicals generated using argon-cold atmospheric plasma (Ar-CAP) in aqueous solutions and intracellularly in comparison with those generated by X-irradiation. Ar-CAP was generated using a high-voltage power supply unit with low-frequency excitation. The characteristics of Ar-CAP were estimated by vacuum UV absorption and emission spectra measurements. Hydroxyl (·OH) radicals and hydrogen (H) atoms in aqueous solutions were identified with the spin traps 5,5-dimethyl-1-pyrroline N-oxide (DMPO), 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO), and phenyl N-t-butylnitrone (PBN). The occurrence of Ar-CAP-induced pyrolysis was evaluated using the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) in aqueous solutions of DNA constituents, sodium acetate, and L-alanine. Human lymphoma U937 cells were used to study intracellular oxidative stress using five fluorescent probes with different affinities to a number of reactive species. The analysis and quantification of EPR spectra revealed the formation of enormous amounts of ·OH radicals using Ar-CAP compared with that by X-irradiation. Very small amounts of H atoms were detected whereas nitric oxide was not found. The formation of ·OH radicals depended on the type of rare gas used and the yield correlated inversely with ionization energy in the order of krypton > argon = neon > helium. No pyrolysis radicals were detected in aqueous solutions exposed to Ar-CAP. Intracellularly, ·OH, H2O2, which is the recombination product of ·OH, and OCl- were the most likely formed reactive oxygen species after exposure to Ar-CAP. Intracellularly, there was no practical evidence for the formation of NO whereas very small amounts of superoxides were formed. Despite the superiority of Ar-CAP in forming ·OH radicals, the exposure to X-rays proved more lethal. The mechanism of free radical formation in aqueous solutions and an intracellular milieu is discussed.


Subject(s)
Argon/chemistry , Free Radicals/analysis , Intracellular Fluid/chemistry , Plasma Gases/chemistry , Solutions/chemistry , Cell Line , Electron Spin Resonance Spectroscopy/methods , Flow Cytometry/methods , Humans , Intracellular Fluid/radiation effects , Oxidative Stress/radiation effects , Solutions/radiation effects , Spin Trapping/methods , X-Rays
8.
Gene ; 424(1-2): 141-6, 2008 Nov 15.
Article in English | MEDLINE | ID: mdl-18760339

ABSTRACT

Adiponectin plays protective roles against the development of insulin resistance and atherosclerosis. To clarify the regulation of adiponectin gene expression, reporter gene assay by using the several truncated mouse adiponectin 5'-flanking regions was performed after the differentiation of 3T3-L1 preadipocytes. The results indicated that a novel mouse adiponectin enhancer exists in the-2228 to -2066 region. Nuclear proteins from the differentiated adipocytes bound to two DNA fragments, namely, -2153 to -2114 and -2093 to -2054. Both fragments had a common motif, CACAATGC, which was similar to the CCAAT/enhancer binding protein (C/EBP) binding motif. A gel mobility shift assay with anti-C/EBPs antibodies showed that C/EBP alpha, beta, and delta bound to this motif. These data provide the first evidence that the transcriptional activity of the mouse adiponectin gene during adipocyte differentiation is enhanced by the motif in a novel adiponectin enhancer region, via the recruitment of the C/EBPs.


Subject(s)
Adipocytes/physiology , Adiponectin/genetics , CCAAT-Enhancer-Binding Proteins/genetics , Enhancer Elements, Genetic/genetics , Gene Expression Regulation , 3T3 Cells , 5' Untranslated Regions/genetics , Adipocytes/cytology , Adiponectin/isolation & purification , Animals , Base Sequence , Cell Differentiation , DNA Primers , Electrophoretic Mobility Shift Assay , Humans , Mice , Molecular Sequence Data , Plasmids , Sequence Alignment , Sequence Homology, Nucleic Acid
11.
Protein Eng Des Sel ; 18(6): 265-71, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15928005

ABSTRACT

We have developed an efficient optimization technique, 'biased mutation-assembling', for improving protein properties such as thermostability. In this strategy, a mutant library is constructed using the overlap extension polymerase chain reaction technique with DNA fragments from wild-type and phenotypically advantageous mutant genes, in which the number of mutations assembled in the wild-type gene is stochastically controlled by the mixing ratio of the mutant DNA fragments to wild-type fragments. A high mixing ratio results in a mutant composition biased to favor multiple-point mutants. We applied this strategy to improve the thermostability of prolyl endopeptidase from Flavobacterium meningosepticum as a case study and found that the proportion of thermostable mutants in a library increased as the mixing ratio was increased. If the proportion of thermostable mutants increases, the screening effort needed to find them should be reduced. Indeed, we isolated a mutant with a 1200-fold longer activity half-life at 60 degrees C than that of wild-type prolyl endopeptidase after screening only 2000 mutants from a library prepared with a high mixing ratio. Our results indicate that an aggressive accumulation of advantageous mutations leads to an increase in the quality of the mutant library and a reduction in the screening effort required to find superior mutants.


Subject(s)
Chryseobacterium/enzymology , Directed Molecular Evolution , Hot Temperature , Mutation , Serine Endopeptidases/genetics , Chryseobacterium/genetics , Gene Expression , Gene Library , Genetic Vectors , Prolyl Oligopeptidases , Protein Engineering , Serine Endopeptidases/chemistry , Serine Endopeptidases/metabolism , Thermodynamics
12.
Biochem Biophys Res Commun ; 325(4): 1487-94, 2004 Dec 24.
Article in English | MEDLINE | ID: mdl-15555596

ABSTRACT

Ghrelin, discovered in rat stomach as an endogenous growth hormone secretagogue, is octanoylated at the Ser3 residue. Since this octanoylation is essential for the functions of ghrelin, the enzymes that catalyze acylation for ghrelin biosynthesis and deacylation (deactivation step) must be considered as important regulators. We found that rat stomach homogenate contained ghrelin deacylation activity, and we isolated the active fractions by column chromatography. After sequencing and expressing candidate proteins, the ghrelin deacylation enzyme in the stomach was identified as lysophospholipase I (LysoPLA I). The enzyme properties were examined using recombinant rat LysoPLA I expressed in Escherichia coli. K(m) and V(max) values were determined as 6.5 microM and 2.3 micromol/min/mg for ghrelin and 2.2 x 10(2) microM and 0.5 micromol/min/mg for lysophosphatidylcholine (LysoPC), respectively. The deacylation of both substrates was inhibited by methyl arachidonyl fluorophosphonate (MAFP), which is known as an irreversible inhibitor of LysoPLA I. These results reveal that LysoPLA I catalyzes the removal of n-octanoic acid from ghrelin to form des-acyl ghrelin. Identification of the ghrelin deacylation enzyme in the stomach and a deacylation inhibitor will be helpful in investigating ghrelin biosynthesis.


Subject(s)
Gastrointestinal Contents/chemistry , Gastrointestinal Contents/enzymology , Peptide Hormones/chemistry , Peptide Hormones/metabolism , Stomach/enzymology , Thiolester Hydrolases/chemistry , Thiolester Hydrolases/metabolism , Acylation , Amino Acid Sequence , Animals , Enzyme Activation , Ghrelin , Molecular Sequence Data , Molecular Weight , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Substrate Specificity , Thiolester Hydrolases/genetics
13.
Biopolymers ; 64(2): 95-105, 2002 Jul 05.
Article in English | MEDLINE | ID: mdl-11979520

ABSTRACT

We present a method for analysis of a fitness landscape of a biopolymer with significantly epistatic sites. The analysis is based on a quasi-additive fitness model. The fitness model is constructed with additive terms conducted by "site-fitness" and epistatic terms conducted by "pair-fitness," where the site-fitness is a fitness contribution from an independent residue and the pair-fitness is a fitness contribution from a pair of epistatic residues. As a case study, we analyzed the sequence-fitness data for 45 clones of thermostable prolyl endopeptidase mutants. They were generated by a mutation scrambling method, which can accumulate advantageous mutations. The fitness contributions from 14 single-point mutations including E67Q and Q656R were identified by the analysis. As a result, we found that the fitness model with a significant epistatic term by a pair of the 67th site and 656th site was in good agreement with the experimental data and that the explored landscape in the binary 14-dimensional sequence space is still a mountainous landscape with twin peaks. The validity was supported by the analysis of mutant fitness distributions derived from another mutation scrambling experiment and by (3D) structural data.


Subject(s)
Serine Endopeptidases/chemistry , Directed Molecular Evolution , Half-Life , Models, Molecular , Mutation , Prolyl Oligopeptidases , Serine Endopeptidases/genetics , Thermodynamics
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