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1.
Food Microbiol ; 91: 103542, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32539947

ABSTRACT

Psychrotolerant species of the Bacillus cereus group, Bacillus mycoides and Bacillus weihenstephanensis, can grow at ≥ 7 °C and are significant concerns for the food industry due to their ability to cause spoilage of refrigerated food. In addition to that, some strains of B. weihenstephanensis can produce emetic toxin, namely cereulide, which is known to cause vomiting. Therefore, rapid and simple methods to discriminate psychrotolerant B. cereus group species are crucial. Here, matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) and the S10-spc-alpha operon gene encoded ribosomal protein mass spectrum (S10-GERMS) method were used to discriminate psychrotolerant species of the B. cereus group based on a set of four ribosomal subunit proteins (S10, S16, S20 and L30). A total of 36 strains of B. cereus group were cultured on LB agar, and analyzed by MALDI-TOF MS. The four biomarkers successfully discriminated 12 strains of psychrotolerant species from mesophilic species of the B. cereus group. Furthermore, the four biomarkers also classified some Bacillus thuringiensis strains. MALDI-TOF MS analysis using the S10-GERMS method allowed simple and rapid discrimination of psychrotolerant species of the B. cereus group from other mesophilic species. This method has a possibility to enable manufacturers and distributors of refrigerated foods to control psychrotolerant species of the B. cereus group effectively.


Subject(s)
Bacillus/classification , Bacterial Proteins/analysis , Ribosomal Proteins/analysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Bacillus/chemistry , Bacillus/genetics , Bacillus/growth & development , Bacterial Proteins/genetics , Bacterial Typing Techniques , Biomarkers/analysis , Cold Temperature , Food Microbiology , Operon , Ribosomal Proteins/genetics , Species Specificity
4.
Appl Microbiol Biotechnol ; 101(23-24): 8557-8569, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29032472

ABSTRACT

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based microbial identification is a popular analytical method. Strain Solution proteotyping software available for MALDI-TOF MS has great potential for the precise and detailed discrimination of microorganisms at serotype- or strain-level, beyond the conventional mass fingerprinting approaches. Here, we constructed a theoretically calculated mass database of Salmonella enterica subspecies enterica consisting of 12 biomarker proteins: ribosomal proteins S8, L15, L17, L21, L25, and S7, Mn-cofactor-containing superoxide dismutase (SodA), peptidyl-prolyl cis-trans isomerase C (PPIase C), and protein Gns, and uncharacterized proteins YibT, YaiA, and YciF, that can allow serotyping of Salmonella. Strain Solution ver. 2 software with the novel database constructed in this study demonstrated that 109 strains (94%), including the major outbreak-associated serotypes, Enteritidis, Typhimurium, and Infantis, could be correctly identified from others by colony-directed MALDI-TOF MS using 116 strains belonging to 23 kinds of typed and untyped serotypes of S. enterica from culture collections, patients, and foods. We conclude that Strain Solution ver. 2 software integrated with the accurate mass database will be useful for the bacterial proteotyping by MALDI-TOF MS-based microbial classification in the clinical and food safety fields.


Subject(s)
Bacterial Proteins/analysis , Bacterial Proteins/chemistry , Computational Biology/methods , Salmonella enterica/chemistry , Salmonella enterica/classification , Serotyping/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Food Microbiology , Humans , Salmonella Infections/microbiology , Salmonella enterica/isolation & purification , Software
5.
Bioorg Med Chem ; 21(11): 2968-74, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23611768

ABSTRACT

Although flavones act as potent androgen receptor (AR) antagonists, it remains unclear how flavones interact with AR. The aim of this in silico study was to investigate the molecular recognition processes of newly synthesized 5,4'-difluoroflavone with the highest activity (IC50 value=0.19 µM) in the AR-ligand binding domain (AR-LBD). The results demonstrated that at its 4'-position of 5,4'-difluoroflavone the substituents may face Arg752 and that in AR-LBD, the submolecular bulk of substituents is unfavorable for AR antagonists and the negative electrostatic interaction site prefers the stronger hydrogen bond capability of substituents of AR antagonists. The prediction model is a valuable tool for designing a novel AR antagonist.


Subject(s)
Androgen Receptor Antagonists/chemistry , Flavones/chemistry , Molecular Docking Simulation , Receptors, Androgen/chemistry , Binding Sites , Drug Design , Halogenation , Humans , Hydrogen Bonding , Kinetics , Protein Binding , Static Electricity , Structure-Activity Relationship
6.
J Invasive Cardiol ; 35(8): E375-E383, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37983097

ABSTRACT

A 57-year-old woman with critical limb-threatening ischemia (CLTI) of the left lower leg underwent endovascular therapy. She had undergone a femoropopliteal (F-P) bypass for treatment of chronic total occlusion (CTO) of the superficial femoral artery (SFA) four years prior.


Subject(s)
Femoral Artery , Vascular Diseases , Female , Humans , Middle Aged , Femoral Artery/diagnostic imaging , Femoral Artery/surgery , Leg , Stents
7.
Oxf Med Case Reports ; 2023(4): omad038, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37091683

ABSTRACT

Left anterior descending artery (LAD) occlusion normally develops into precordial ST-segment elevation; however, we describe a case of a 50-year-old man with inferior and precordial ST-segment elevation myocardial infarction that resulted from proximal occlusion of the wrap-around LAD perfusing the anterior and inferior wall. We performed early and prompt reperfusion and were able to save the patient without any complications. A wrap-around LAD perfuses a large myocardial area; therefore, this type of coronary occlusion causes severe myocardial damage and has a poor prognosis. The rates of new-onset heart failure and heart failure rehospitalization are also high. Simultaneous inferior and precordial ST-segment elevations on electrocardiography suggest acute myocardial infarction with a wrap-around LAD lesion, which requires prompt revascularization. More careful medications for heart failure and follow-up should be also required even after discharge in such case.

8.
Eur Heart J Case Rep ; 7(2): ytad040, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36761282

ABSTRACT

A 77-year-old man presented with dyspnoea and was diagnosed with chronic thromboembolic pulmonary hypertension. Balloon pulmonary angioplasty was attempted; however, the balloons could not be advanced to the total occlusion lesion in the right A3 segment. The obstruction was overcome using a microcatheter Corsair (AsahiKASEI). This technique may be useful in managing a total occlusion lesion.

9.
Cureus ; 15(2): e34846, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36923181

ABSTRACT

Pulmonary endarterectomy (PEA) is the standard treatment for chronic thromboembolic pulmonary hypertension (CTEPH). However, repeating surgery in recurrent cases is generally deemed high-risk. Balloon pulmonary angioplasty (BPA), an alternative treatment for organized thrombotic lesions of the peripheral pulmonary artery, has also shown a good prognosis in cases of inoperable CTEPH. Here, we report the case of a 65-year-old woman who presented with dyspnea. She had been admitted to our hospital in 2015 and diagnosed with University of San Diego (USD)-California classification CTEPH of level II. PEA had been performed, which resolved her respiratory discomfort, and her WHO functional class had improved from IV to I. Post-surgery pulmonary angiography had shown several residual lesions; nonetheless, pulmonary hypertension had not been noted, and the patient had not experienced dyspnea thereafter. We had decided to continue medical therapy; however, the patient stopped taking anticoagulation and pulmonary vasodilators due to the absence of symptoms. In 2021, dyspnea recurred, and she was hospitalized for examination. Chest radiography showed no cardiomegaly, and heart failure and tricuspid regurgitation were absent on echocardiography. The six-minute walk test distance was 565 m, and the lowest oxygen saturation during the test was 92%. Right heart catheterization demonstrated a mean pulmonary arterial pressure (PAP) of 15 mmHg without pulmonary hypertension; however, pulmonary angiography showed new organized thrombotic lesions in the left segments of the lower lobe. Based on the advancement of the lesions, we speculated that they were the cause of the symptoms even without concurrent pulmonary hypertension. Therefore, we performed two additional BPA procedures. Subsequently, the mean PAP decreased further to 13 mmHg. The patient's symptoms improved, the six-minute walk test distance increased to 656 m, and the WHO functional class returned to I. In conclusion, BPA for recurrent lesions after surgery for CTEPH can improve the patient's symptoms and exercise tolerance.

10.
Eur Heart J Case Rep ; 7(3): ytad106, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36949868

ABSTRACT

Background: Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare thromboembolic disease, with occasional critical consequences. Essential thrombocythaemia (ET) is associated with an increased incidence of venous and arterial thrombotic events. In addition, the JAK2-V617F mutation increases the risk of thrombosis. Few reports have evaluated the utility of balloon pulmonary angioplasty (BPA) for worsening CTEPH with ET and the JAK2-V617F mutation. Case Summary: A 76-year-old woman, diagnosed with ET and the JAK2-V617F mutation, presented with dyspnoea. Echocardiography showed severe tricuspid regurgitation with a flattened interventricular septum. Contrast-enhanced computed tomography showed an eccentric thrombus in the right main pulmonary artery (PA) and thrombi in bilateral peripheral PAs. Acute pulmonary embolism (PE) was initially diagnosed, and heparinization was initiated; however, her oxygen saturation gradually worsened despite continued anticoagulation therapy. Her oxygen saturation level decreased to 90% (under a reservoir mask of 10 L). Her haemodynamics suggested CTEPH comorbidity. We decided to perform emergency right heart catheterization (RHC) and pulmonary angiography (PAG). RHC showed severe pulmonary hypertension. PAG showed fresh and organized thrombi and web regions in several segmental PAs. These findings indicated a combination of acute PE and CTEPH. Rescue BPA was performed on the right A1, A3, A8, and A9 segments. After BPA, the patient's oxygen saturation showed marked improvement. The patient was discharged 18 days after hospitalization without complications. Discussion: Rescue BPA could be an effective treatment for worsening CTEPH in severely impaired conditions, even with ET and the JAK2-V617F mutation.

11.
Microorganisms ; 11(1)2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36677494

ABSTRACT

Identification of microorganisms by MALDI-TOF MS has become a popular method in the past 20 years. Strain Solution ver. 2 software appended with MALDI-TOF MS enables accurate discrimination of serotypes and strains beyond the genus and species level by creating a theoretical mass-based database. In this study, we constructed a theoretical mass database with the validated biomarkers to proteotype Campylobacter jejuni. Using 10 strains belonging to Campylobacter spp. available from culture collections and 41 Campylobacter jejuni strains isolated from humans and foods, the ribosomal protein subunits L36, L32, S14, L24, L23, L7/L12, and S11 could be selected as the effective biomarkers for the proteotyping of C. jejuni at MALDI-TOF MS. An accurate database of their theoretical mass-based values was constructed by matching these gene DNA sequences and the observed mass peaks. We attempted to automatically classify 41 strains isolated from nature using this database and Strain Solution ver. 2 software, and 38 strains (93%) were correctly classified into the intended group based on the theoretical mass-based values. Thus, the seven biomarkers found in this study and Strain Solution ver. 2 are promising for the proteotyping of C. jejuni by MALDI-TOF MS.

12.
J Pestic Sci ; 47(3): 111-117, 2022 Aug 20.
Article in English | MEDLINE | ID: mdl-36479453

ABSTRACT

Biological soil disinfestation (BSD) is biotechnology to control soil-borne plant pathogens based on the anaerobic-reducing environment in soil and the functions of indigenous microbes. A new sustainable agricultural technology, the GET system, which produces and recovers methane as renewable energy from paddy fields, has a structure and principles similar to those of BSD technology. To confirm the potential of the GET system as BSD technology, the microbial community structures in the GET system were analyzed using next-generation sequencing. Thirty-four phyla were detected: 31 bacterial and 3 archaeal. Firmicutes dominated during the experimental period, which plays an important role in BSD functions such as organic decomposition, nitrate removal, and soil-borne pathogen elimination. The ability of the GET system to control soil-borne pathogens as well as produce renewable energy was demonstrated.

13.
Clin Case Rep ; 10(12): e6738, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36523383

ABSTRACT

The standard treatment of chronic thromboembolic pulmonary hypertension (CTEPH) is pulmonary endarterectomy (PEA); however, it may be unsuitable in the presence of comorbidities such as cardiac shock and severe hypoxia. We describe a successful case of emergent balloon pulmonary angioplasty performed before PEA in a patient with deteriorating central-type CTEPH.

14.
J Food Prot ; 85(8): 1192-1202, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35687734

ABSTRACT

ABSTRACT: Cereulide-producing Bacillus cereus, which causes foodborne illnesses with vomiting, and psychrotolerant B. cereus group strains such as Bacillus mycoides, which can grow at ≥7°C and cause spoilage of refrigerated foods, are significant concerns for the food industry. Rapid and simple methods to discriminate the cereulide-producing B. cereus and psychrotolerant B. cereus group strains from other B. cereus group strains are needed. We developed a novel, rapid, and simple method with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analysis for simultaneous discrimination of these two groups from other B. cereus group strains. A potassium adduct of cereulide was used to detect cereulide-producing B. cereus, and three ribosomal subunit proteins (L30, S16, and S20) were used to detect psychrotolerant B. cereus group. A total of 51 B. cereus group strains were analyzed by MALDI-TOF MS. The biomarkers allowed successful discrimination of 16 cereulide-producing B. cereus and 15 psychrotolerant B. cereus group strains from other B. cereus group strains. The results showed that this MALDI-TOF MS analysis allows simultaneous discrimination of cereulide-producing B. cereus and psychrotolerant B. cereus group strains from other B. cereus group strains. This efficient method has the potential to be a valuable tool for ensuring food safety.


Subject(s)
Bacillus cereus , Depsipeptides , Depsipeptides/analysis , Depsipeptides/metabolism , Lasers , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
15.
Neural Netw ; 143: 550-563, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34304003

ABSTRACT

Reservoir computing is a machine learning framework derived from a special type of recurrent neural network. Following recent advances in physical reservoir computing, some reservoir computing devices are thought to be promising as energy-efficient machine learning hardware for real-time information processing. To realize efficient online learning with low-power reservoir computing devices, it is beneficial to develop fast convergence learning methods with simpler operations. This study proposes a training method located in the middle between the recursive least squares (RLS) method and the least mean squares (LMS) method, which are standard online learning methods for reservoir computing models. The RLS method converges fast but requires updates of a huge matrix called a gain matrix, whereas the LMS method does not use a gain matrix but converges very slow. On the other hand, the proposed method called a transfer-RLS method does not require updates of the gain matrix in the main-training phase by updating that in advance (i.e., in a pre-training phase). As a result, the transfer-RLS method can work with simpler operations than the original RLS method without sacrificing much convergence speed. We numerically and analytically show that the transfer-RLS method converges much faster than the LMS method. Furthermore, we show that a modified version of the transfer-RLS method (called transfer-FORCE learning) can be applied to the first-order reduced and controlled error (FORCE) learning for a reservoir computing model with a closed-loop, which is challenging to train.


Subject(s)
Machine Learning , Neural Networks, Computer , Least-Squares Analysis
16.
Microorganisms ; 9(6)2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34201063

ABSTRACT

Matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is a widely used and reliable technology to identify microbial species and subspecies. The current methodology is based on spectral fingerprinting, analyzing protein peaks, most of which are yet to be characterized. In order to deepen the understanding of these peaks and to develop a more reasonable identification workflow, we applied proteogenomic approaches to assign the high-intensity peaks of MALDI-TOF spectra of two bacterial genera. First, the 3-22 kD proteomes of 5 Cutibacterium strains were profiled by UPLC-MS/MS, and the amino acid sequences were refined by referring to their genome in the public database. Then, the sequences were converted to m/z (x-axis) values based on their molecular masses. When the interspecies comparison of calculated m/z values was well-fitted to the observed peaks, the peak assignments for the five Cutibacterium species were confirmed. Second, the peak assignments for six Staphylococcus species were performed by using the above result for Cutibacterium and referring to ribosomal subunit proteins coded on the S10-spc-alpha operon (the S10-GERMS method), a previous proteomics report by Becher et al., and comprehensive genome analysis. We successfully assigned 13 out of 15 peaks for the Cutibacterium species and 11 out of 13 peaks for the Staphylococcus species. DNA-binding protein HU, the CsbD-like protein, and 50S ribosomal protein L7/L12 were observed in common. The commonality suggests they consist of high-intensity peaks in the MALDI spectra of other bacterial species. Our workflow may lead to the development of a more accurate species identification database of MALDI-TOF mass spectrometry based on genome data.

17.
Microorganisms ; 9(11)2021 Nov 12.
Article in English | MEDLINE | ID: mdl-34835467

ABSTRACT

Cutibacterium modestum is a new species coined in 2020 as the fifth species of genus Cutibacterium, which includes Cutibacterium acnes. The species is predicted as a minor but common member of skin microbiome and includes a group tentatively named as "Propionibacterium humerusii". The description of the species has been provided only with a single strain. To establish the characteristics of C. modestum and search for possible disease-related subtypes, we investigated the biochemical characteristics of eight live strains and performed in silico comparison of nine genomes. The common features, which included the morphology of Gram-stain positive short rods, the negativity of phenylalanine arylamidase, and several unique MALDI-TOF MS spectral peaks, were considered useful in laboratory identification. Pairwise comparisons of the genomes by in silico DNA-DNA hybridization showed similarity values of 98.1% or larger, which were far higher than the subspecies cutoff of 79-80%. The 16S rRNA gene sequences of thirteen isolates and genomes were identical. Their recA gene sequences were identical except for two strains, HM-510 (HL037PA2) and Marseille-P5998, which showed unique one-nucleotide polymorphisms. The biochemical features using API kits were slightly different among the isolates but far closer than those of the nearest other species, C. acnes and Cutibacterium namnetense. Spectra of MALDI-TOF mass spectrometry showed slight differences in the presence of m/z 10,512 (10 kD chaperonin GroS) and three other peaks, further clustering the eight isolates into three subtypes. These results indicated that these isolates did not separate to form subspecies-level clusters, but subtyping is possible by using recA gene sequences or MALDI-TOF mass spectrometry spectra. Moreover, this work has confirmed that a group "P. humerusii" is included in C. modestum.

18.
J Proteome Res ; 9(12): 6722-8, 2010 Dec 03.
Article in English | MEDLINE | ID: mdl-20945934

ABSTRACT

We have proposed a rapid phylogenetic classification at the strain level by MALDI-TOF MS using ribosomal protein matching profiling. In this study, the S10-spc-alpha operon, encoding half of the ribosomal subunit proteins and highly conserved in eubacterial genomes, was selected for construction of the ribosomal protein database as biomarkers for bacterial identification by MALDI-TOF MS analysis to establish a more reliable phylogenetic classification. Our method revealed that the 14 reliable and reproducible ribosomal subunit proteins with less than m/z 15,000, except for L14, coded in the S10-spc-alpha operon were significantly useful biomarkers for bacterial classification at species and strain levels by MALDI-TOF MS analysis of genus Pseudomonas strains. The obtained phylogenetic tree was consisted with that based on genetic sequence (gyrB). Since S10-spc-alpha operons of genus Pseudomonas strains were sequenced using specific primers designed based on nucleotide sequences of genome-sequenced strains, the ribosomal subunit proteins encoded in S10-spc-alpha operon were suitable biomarkers for construction and correction of the database. MALDI-TOF MS analysis using these 14 selected ribosomal proteins is a rapid, efficient, and versatile bacterial identification method with the validation procedure for the obtained results.


Subject(s)
Bacterial Proteins/analysis , Pseudomonas/metabolism , Ribosomal Proteins/analysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Bacterial Proteins/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Databases, Protein , Molecular Sequence Data , Operon , Phylogeny , Protein Subunits/analysis , Protein Subunits/genetics , Pseudomonas/classification , Pseudomonas/genetics , Ribosomal Proteins/genetics , Sequence Analysis, DNA , Species Specificity
19.
Bioorg Med Chem Lett ; 20(7): 2111-4, 2010 Apr 01.
Article in English | MEDLINE | ID: mdl-20226658

ABSTRACT

The effect of essential oils, such as raspberry ketone, on androgen (AR) receptor was investigated using a MDA-kb2 human breast cancer cell line for predicting potential AR activity. Among them, eugenol had the highest AR antagonistic activity with its IC(50) value of 19 microM. Raspberry ketone, which has threefold higher anti-obese activity than that of capsaicin, also had AR antagonist activity with its IC(50) value of 252 microM. Based on these findings, a more precise CoMFA model was proposed as follows: pIC(50) [log (1/IC(50))]=3.77+[CoMFA field terms] (n=39, s=0.249, r(2)=0.834, s(cv)=0.507, q(2)=0.311 (three components).


Subject(s)
Androgen Antagonists/pharmacology , Androgen Receptor Antagonists , Butanones/pharmacology , Oils, Volatile/pharmacology , Receptors, Androgen/metabolism , Androgen Antagonists/chemistry , Butanones/chemistry , Cell Line, Tumor , Genes, Reporter , Humans , Inhibitory Concentration 50 , Models, Molecular , Oils, Volatile/chemistry , Protein Binding , Receptors, Androgen/chemistry
20.
Chem Pharm Bull (Tokyo) ; 58(8): 1107-10, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20686270

ABSTRACT

A variety of 5,4'-disubstituted flavones, which are anticipated to be androgen receptor antagonists to treat diseases mediated by the androgen receptor, were synthesized. It was found that an intramolecular ipso-substitution reaction via cesium enolate using 2-fluoro-6-hydroxyacetophenone and various benzoyl chlorides was effective in the preparation of 5-hydroxy-4'-alkylflavones.


Subject(s)
Cesium/chemistry , Flavones/chemistry , Flavones/chemical synthesis , Androgen Receptor Antagonists/chemical synthesis , Androgen Receptor Antagonists/chemistry , Flavones/pharmacology , Molecular Structure , Stereoisomerism
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