Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
1.
ACS Appl Mater Interfaces ; 16(3): 3509-3519, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38225735

RESUMO

Not all encapsulation techniques are universally apt for every type of phase change material (PCM), highlighting the imperative for methodological precision. This study addresses the challenges of microencapsulated PCM (MEPCM) arising from the immiscible pairing of α-Al2O3 nanoparticles with Sn microparticles. The high-speed impact blending (HIB) dry synthesis technique is employed, facilitating large-volume production of Sn@α-Al2O3 MEPCMs. The resulting MEPCMs not only seamlessly endure 100 cycles of melting-solidification but also, with the strategic incorporation of a glass frit, exhibit remarkable thermal durability, withstanding up to 1000 melting-solidification cycles. Even under ultrafast thermal fluctuations, the α-Al2O3 shell remained resilient through 100 cycles. A marked reduction in supercooling is observed, which is attributed to the formation of SnO and SnO2 nanoparticles within the α-Al2O3 crystal lattice. The atomically resolved interface dynamics between SnO2 and α-Al2O3 play a pivotal role, lowering the energy barrier for Sn nuclei formation during solidification. This affects the accelerated Sn nucleation rate, effectively suppressing supercooling. Such insights offer a deeper understanding of the interplay between nanoscale crystal lattice imperfections and their implications for energy storage applications.

2.
Heliyon ; 9(10): e20167, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800060

RESUMO

Background: We performed molecular epidemiological analyses of Clostridioides difficile isolates in a university hospital in Japan to reveal the risk of C. difficile infection. Methods: Cultured isolates from 919 stool samples from 869 patients obtained from July 2015 to August 2016 were subjected to toxin gene detection, ribotyping, multilocus sequence typing, antimicrobial susceptibility testing, and quantitative real-time polymerase chain reaction testing for C. difficile toxin gene expression. Results: Of the 919 stool samples from 869 patients, C. difficile was isolated from 153 samples (16.6%), of which 49 (32%) and 104 (68%) were from patients with and without C. difficile infection, respectively. Analyses showed genetic diversity, with ST8 and ST17 strains of healthcare-associated infections, some of which caused C. difficile infections. There was no significant difference in the transcription levels of C. difficile toxin genes between isolates from patients with and without C. difficile infection. Conclusions: Major Japanese clonal strains, ST8 and ST17, have been in the hospital environment for a long time and cause healthcare-associated C. difficile infections. The C. difficile toxin genes were transcribed in the isolates from both patients with and without C. difficile infection but were no significant relationship with the development of C. difficile infection.

3.
Antimicrob Agents Chemother ; 67(4): e0161922, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36975786

RESUMO

Antimicrobial resistance (AMR) of bacterial pathogens, including enterococci, is a global concern, and plasmids are crucial for spreading and maintaining AMR genes. Plasmids with linear topology were identified recently in clinical multidrug-resistant enterococci. The enterococcal linear-form plasmids, such as pELF1, confer resistance to clinically important antimicrobials, including vancomycin; however, little information exists about their epidemiological and physiological effects. In this study, we identified several lineages of enterococcal linear plasmids that are structurally conserved and occur globally. pELF1-like linear plasmids show plasticity in acquiring and maintaining AMR genes, often via transposition with the mobile genetic element IS1216E. This linear plasmid family has several characteristics enabling long-term persistence in the bacterial population, including high horizontal self-transmissibility, low-level transcription of plasmid-carried genes, and a moderate effect on the Enterococcus faecium genome alleviating fitness cost and promoting vertical inheritance. Combining all of these factors, the linear plasmid is an important factor in the spread and maintenance of AMR genes among enterococci.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Humanos , Enterococcus faecium/genética , Antibacterianos/farmacologia , Enterococcus , Plasmídeos/genética , Vancomicina/farmacologia , Infecções por Bactérias Gram-Positivas/microbiologia
4.
ACS Omega ; 7(32): 28313-28323, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35990461

RESUMO

Gallium has been considered for application in the thermal management of electronic equipment because of its high heat transfer ability and heat storage density. To address the issues of metal corrosion and leakage, a microencapsulation method, through which a stable corrosion-resistant ceramic shell can be formed from the liquid metal, is proposed. In this study, an optimized fabrication method for a microencapsulated phase change material (MEPCM) consisting of liquid-state Ga droplets, possessing high durability and heat storage density, is presented. A fabrication route comprising particle formation, hydrothermal treatment, and calcination is proposed. In particular, the thickness and crystal size of the GaOOH shell are controlled by changing the pH during hydrothermal treatment to produce a highly durable shell. The morphology and microstructure, phase composition, heat storage capacity, and durability of the prepared Ga-MEPCM are investigated. In addition, treatment conditions and the shell formation mechanism are analyzed. The results show that pH 9 is the most suitable shell-forming condition, at which the thickest Ga2O3 shell with the smallest crystal size can be produced, which is beneficial for ensuring durability. The MEPCM achieved 200 cycles without leakage and 300 cycles without shape deformation with a high heat storage density of 369.4 J·cm-3.

5.
Zoolog Sci ; 39(4)2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35960030

RESUMO

The effects of mechanical stress on cultured muscle cells were examined with particular interest in myofibril assembly by using a cell-stretching system. We observed that formation and maintenance of cross-striated myofibrils in chick muscle cell cultures was suppressed in the media containing higher concentration of KCl, tetrodotoxin, or ML-9 (an inhibitor of myosin light chain kinase), but periodic stretching of myotubes for several days enabled formation of striated myofibrils just as in standard muscle cultures. However, ryanodine (a blocker of the Ca2 + channel in sarcoplasmic reticulum) and BDM (an inhibitor of myosin-actin interaction) suppressed the stretch-induced myofibrillogenesis. We further found that stretching of myotubes causes quick and transient elevation of the intracellular Ca2 + concentration and this elevation is disturbed by inhibition of Ca2 + channels of sarcoplasmic reticulum and suppression of Ca2 + influx from culture medium. These observations indicate that periodic stretching induces elevation of intracellular Ca2 + concentration and that this elevation may be due to release of Ca2 + from sarcoplasmic reticulum and Ca2 + influx from outside of the cells. The increased Ca2 + may activate actin-myosin interaction by interacting with troponin that is located along actin filaments and/or inducing phosphorylation of myosin light chains and thereby promote myofibril assembly.


Assuntos
Actinas , Miofibrilas , Animais , Células Cultivadas , Desenvolvimento Muscular , Fibras Musculares Esqueléticas , Miosinas/farmacologia
6.
Nucleosides Nucleotides Nucleic Acids ; 41(12): 1296-1304, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35921584

RESUMO

Hospital meals are prepared with the nutrients required by the patient's medical condition in consideration. However, no research on the purine content of hospital meals has been conducted, and it is not shown on the purine content. The recommended purine consumption for patients with gout and hyperuricemia is 400 mg/day based on the Japanese guidelines for the management of hyperuricemia and gout. In this study, the purine content in hospital meals was evaluated using the purine content of foods previously determined by our laboratory as a reference. The serum uric acid levels and uric acid excretion in admitted patients who consumed these diets were examined.


Assuntos
Gota , Hiperuricemia , Humanos , Ácido Úrico , Purinas , Refeições , Concentração de Íons de Hidrogênio , Hospitais
7.
JAC Antimicrob Resist ; 4(1): dlab189, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34993479

RESUMO

BACKGROUND: VanD is a rare type of vancomycin resistance worldwide. However, the host diversity of the vanD gene cluster and the structural similarity of their genomic islands are not well understood. METHODS: Three VanD-type Enterococcus faecium strains (AA620, AA622 and AA624) isolated from a Japanese patient who underwent vancomycin treatment in 2017 were analysed. This study utilized WGS analysis to characterize the three VanD-type E. faecium strains and describes the diversity of hosts possessing VanD-carrying genomic islands. RESULTS: The three isolates exhibited variable MICs of vancomycin. In the relatively vancomycin-resistant AA620, mutations were identified in vanSD and ddl. The strains AA622 and AA624 had intact ddl and harboured two vanD gene clusters. qRT-PCR results revealed the ddl mutation to be a factor affecting the high vancomycin resistance range of AA620. WGS data showed the 155 kb and 185 kb genomic islands harbouring the vanD gene cluster inserted in the coding region of the lysS gene, located in the chromosome in AA620 and AA622/624, respectively. Comparing the VanD-carrying genomic islands to available sequences of other enterococci and enteric anaerobes revealed how the genomic islands of these organisms isolated worldwide shared similar core genes and backbones. These anaerobes belonged to various genera within the order Eubacteriales. The phylogenetic cluster of the genomic island core genome alignment did not correlate with the host-species lineage, indicating horizontal gene transfer in the gut microbiota. CONCLUSIONS: By horizontal gene transfer, various bacteria forming the gut microbiota maintain VanD-carrying genomic islands.

8.
Sci Rep ; 11(1): 7539, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824354

RESUMO

CO2 methanation is a promising technology to enable the use of CO2 as a resource. Thermal control of CO2 methanation, which is a highly active exothermic reaction, is important to avoid thermal runaway and subsequent degradation of the catalyst. Using the heat storage capacity of a phase change material (PCM) for thermal control of the reaction is a novel passive approach. In this study a novel structure was developed, wherein catalysts were directly loaded onto a micro-encapsulated PCM (MEPCM). The MEPCM was prepared in three steps consisting of a boehmite treatment, precipitation treatment, and heat oxidation treatment, and an impregnation process was adopted to prepare a Ni catalyst. The catalyst-loaded MEPCM did not show any breakage or deformation of the capsule or a decrease in the heat storage capacity after the impregnation treatment. MEPCM demonstrated a higher potential as an alternative catalyst support in CO2 methanation than the commercially available α-Al2O3 particle. In addition, the heat storage capacity of the catalyst-loaded MEPCM suppressed the temperature rise of the catalyst bed at a high heat absorption rate (2.5 MW m-3). In conclusion, the catalyst-loaded MEPCM is a high-speed, high-precision thermal control device because of its high-density energy storage and resolution of a spatial gap between the catalyst and cooling devices. This novel concept has the potential to overcome the technical challenges faced by efficiency enhancement of industrial chemical reactions.

9.
Jpn J Infect Dis ; 74(1): 79-81, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-32741928

RESUMO

Five novel strains of Serratia fonticola that produce FONA, a minor extended-spectrum beta-lactamase (ESBL), were isolated during routine surveillance of ESBL-producing Enterobacteriaceae in imported chicken meat in Japan in 2017 and 2018. These strains exhibited a clear ESBL phenotype in susceptibility tests carried out in the presence of clavulanic acid; however, all strains tested negative in a multiplex polymerase chain reaction assay used to detect TEM, SHV, and CTX-M ß-lactamase genes. After identification of the bacterial species as S. fonticola, full length blaFONA genes were amplified and the DNA sequences were determined. The blaFONA genes from all 5 strains were different from those previously reported (blaFONA-1 to blaFONA-6); they clustered close to one another but were distinct from previously reported blaFONA genes in a phylogenic analysis based on amino acid sequences.


Assuntos
Proteínas de Bactérias/metabolismo , Carne/microbiologia , Serratia/isolamento & purificação , beta-Lactamases/metabolismo , Animais , Proteínas de Bactérias/genética , Galinhas , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Humanos , Japão , Testes de Sensibilidade Microbiana , Serratia/enzimologia , Serratia/genética
10.
Eur Heart J Case Rep ; 4(3): 1-6, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32617485

RESUMO

BACKGROUND: Limited research has been conducted on the surgical management of the aortic valve in congenitally corrected transposition of great arteries (ccTGA) and to our knowledge there have been no reports on the treatment of bicuspid aortic regurgitation (AR) in ccTGA. We report on a ccTGA patient with bicuspid AR and systemic right ventricule (SRV) dysfunction who underwent transcatheter aortic valve replacement (TAVR). CASE SUMMARY: A 17-year-old male with a history of ccTGA and cerebral palsy diagnosed at birth presented with heart failure. During childhood, he did not experience any heart failure symptoms, however, secondary to progressive bicuspid AR he experienced worsening SRV dysfunction beginning at 15-year-old. Echocardiography showed reduced SRV ejection fraction and severe bicuspid AR. The heart team, including a cardiac surgeon and paediatric cardiologist, discussed the treatment strategies and decided to proceed with TAVR as surgical aortic valve replacement was deemed high risk. TAVR was performed with the 34 mm Evolut R (Medtronic, Minneapolis, MN, USA). Post-operative echocardiography showed severe paravalvular leak (PVL). Therefore, valve-in-valve TAVR using a 29 mm Edwards SAPIEN 3 (Edwards Lifesciences, Irvine, CA, USA) was performed on post-operative Day 2 for PVL reduction. Following second procedure, PVL was significantly improved. The patient was discharged in stable condition. DISCUSSION: This is the first case wherein TAVR was performed for bicuspid AR in a patient with ccTGA. With appropriate preparation and planning and a collaborative multi-disciplinary team approach, TAVR can be a treatment option for severe AR in patients with ccTGA at high risk for surgery.

11.
Heart Vessels ; 35(8): 1060-1069, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32239276

RESUMO

Mechanical complications (MCs) following acute myocardial infarction (AMI), such as ventricular septal rupture (VSR), free-wall rupture (FWR), and papillary muscle rupture (PMR), are fatal. However, the risk factors of in-hospital mortality among patients with MCs have not been previously reported in Japan. The purpose of this study was to evaluate the prognostic factors of in-hospital mortality in these patients. The study cohort consisted of 233 consecutive patients with MCs from the registry of 10 facilities in the Cardiovascular Research Consortium-8 Universities (CIRC-8U) in East Japan between 1997 and 2014 (2.3% of 10,278 AMI patients). The authors conducted a retrospective observational study to analyse the correlation between the subtypes of MCs with in-hospital mortality, clinical data, and medical treatment. We observed a decreasing incidence of MC (1997-2004: 3.7%, 2005-2010: 2.1%, 2011-2014: 1.9%, p < 0.001). In-hospital mortality among patients with MCs was 46%. Thirty-three percent of patients with MCs were not able to undergo surgical repair due to advanced age or severe cardiogenic shock. In-hospital mortality among patients who had undergone surgical repair was 29% (VSR: 21%, FWR: 33%, PMR: 60%). In patients with MCs, hazard ratio for in-hospital mortality according to multivariate analysis of without surgical repair was 5.63 (95% CI 3.54-8.95). In patients with surgical repair, the hazard ratios of blow-out-type FWR (5.53, 95% confidence interval (CI) 2.22-13.76), those with renal dysfunction (3.11, 95% CI 1.37-7.05), and those receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) (3.79, 95% CI 1.81-7.96) were significantly high. Although primary percutaneous coronary intervention (PCI) is associated with decreased incidence of MCs, high in-hospital mortality persisted in patients with MCs that also presented with renal dysfunction and in those requiring VA-ECMO. Early detection and surgical repair of MCs are essential.


Assuntos
Ruptura Cardíaca Pós-Infarto/mortalidade , Mortalidade Hospitalar , Infarto do Miocárdio/mortalidade , Choque Cardiogênico/mortalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Ruptura Cardíaca Pós-Infarto/fisiopatologia , Ruptura Cardíaca Pós-Infarto/terapia , Hospitalização , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Choque Cardiogênico/fisiopatologia , Choque Cardiogênico/terapia , Fatores de Tempo , Resultado do Tratamento
12.
Sci Rep ; 10(1): 3462, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103095

RESUMO

By tuning the physical and chemical pressures of layered perovskite materials we can realize the quantum states of both superconductors and insulators. By reducing the thickness of a layered crystal to a nanometer level, a nanofilm crystal can provide novel quantum states that have not previously been found in bulk crystals. Here we report the realization of high-temperature superconductivity in Ca2RuO4 nanofilm single crystals. Ca2RuO4 thin film with the highest transition temperature Tc (midpoint) of 64 K exhibits zero resistance in electric transport measurements. The superconducting critical current exhibited a logarithmic dependence on temperature and was enhanced by an external magnetic field. Magnetic measurements revealed a ferromagnetic transition at 180 K and diamagnetic magnetization due to superconductivity. Our results suggest the co-appearance of superconductivity and ferromagnetism in Ca2RuO4 nanofilm crystals. We also found that the induced bias current and the tuned film thickness caused a superconductor-insulator transition. The fabrication of micro-nanocrystals made of layered material enables us to discuss rich superconducting phenomena in ruthenates.

13.
J Invasive Cardiol ; 32(2): E18-E26, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32005786

RESUMO

OBJECTIVES: Little information is available on computed tomography (CT)-based predictors of stroke related to transcatheter aortic valve replacement (TAVR). The objective of this study was to determine whether anatomical features of the aortic valve and aorta visualized by CT are predictive parameters of stroke. METHODS: The study included 1270 patients who underwent preprocedural contrast-enhanced CT assessment and TAVR for severe aortic valve stenosis. Twenty-six patients (2.5%) who developed acute strokes that occurred within 48 hours after TAVR and 104 matched patients without strokes were identified, using 1:4 propensity-score matching. The degree of hypoattenuation in the aortic valve leaflets, calcium volume of the aortic valve, and plaque thickness in the aortic wall (the ascending aorta, aortic arch, and descending thoracic aorta) were assessed. RESULTS: There were no differences between the two groups in the degree of hypoattenuation in the aortic valve leaflets and calcium volume of the aortic valve. The plaque thickness of the aortic arch and descending aorta were greater in the stroke group than in the non-stroke group: aortic arch, 2.4 mm (IQR, 1.3-2.8 mm) vs 1.8 mm (IQR, 1.4-2.2 mm), respectively (P<.01); and descending aorta, 2.9 mm (IQR, 2.1-4.2 mm) vs 2.8 mm (IQR, 2.1-3.6 mm); respectively (P=.049). CONCLUSION: Aortic wall plaque thickness measured by contrast-enhanced CT might be a predictive parameter of strokes that occur within 48 hours after TAVR.


Assuntos
Aorta , Estenose da Valva Aórtica , Valva Aórtica , Placa Aterosclerótica , Complicações Pós-Operatórias , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X/métodos , Substituição da Valva Aórtica Transcateter , Idoso , Aorta/diagnóstico por imagem , Aorta/patologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Feminino , Humanos , Masculino , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/prevenção & controle , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Risco Ajustado/métodos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos
15.
Front Microbiol ; 10: 2568, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798546

RESUMO

Vancomycin-resistant enterococci are troublesome pathogens in clinical settings because of few treatment options. A VanA/VanM-type vancomycin-resistant Enterococcus faecium clinical isolate was identified in Japan. This strain, named AA708, harbored five plasmids, one of which migrated during agarose gel electrophoresis without S1 nuclease treatment, which is indicative of a linear topology. We named this plasmid pELF1. Whole genome sequencing (WGS) analysis of the AA708 strain revealed that the complete sequence of pELF1 was 143,316 bp long and harbored both the vanA and vanM gene clusters. Furthermore, mfold analysis and WGS data show that the left end of pELF1 presumably forms a hairpin structure, unlike its right end. The pELF1 plasmid was not digested by lambda exonuclease, indicating that terminal proteins were bound to the 5' end of the plasmid, similar to the Streptomyces linear plasmids. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis results were also consistent with the exonuclease assay results. In retardation assays, DNAs containing the right end of proteinase K-untreated pELF1 did not appear to move as well as the proteinase K-treated pELF1, suggesting that terminal proteins might be attached to the right end of pELF1. Palindromic sequences formed hairpin structures at the right terminal sequence of pELF1; however, sequence similarity with the well-known linear plasmids of Streptomyces spp. was not high. pELF1 was unique as it possessed two different terminal structures. Conjugation experiments revealed that pELF1 could be transferred to E. faecalis, E. faecium, E. casseliflavus, and E. hirae. These transconjugants exhibited not only high resistance levels to vancomycin, but also resistance to streptomycin, kanamycin, and erythromycin. These results indicate that pELF1 has the ability to confer multidrug resistance to Enterococcus spp. simultaneously, which might lead to clinical hazards.

16.
J Invasive Cardiol ; 31(2): E15-E22, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30700626

RESUMO

BACKGROUND: Data are limited regarding the clinical impact of permanent pacemaker implantation (PPI) in patients with low left ventricular ejection fraction (LVEF) after transcatheter aortic valve replacement (TAVR). The aim of this study was to determine the impact of new PPI in patients with baseline low LVEF at 2-year follow-up after TAVR. METHODS: A total of 659 patients undergoing TAVR between January 2013 and December 2015 were included in the study. Patients were divided into two groups according to the need for PPI after TAVR. These patients were further divided by their baseline LVEF: low LVEF (≤50%) and preserved LVEF (>50%). RESULTS: A total of 104 patients (15.8%) needed PPI following TAVR. After a median follow-up of 19.1 months (interquartile range, 11.4-24.4 months), overall and cardiovascular survival showed no significant differences between new PPI and no PPI (overall, log-rank P=.94; cardiovascular, log-rank P=.51). Nonetheless, patients requiring PPI who had low LVEF had higher cardiovascular mortality compared to patients with low LVEF who didn't need PPI (log-rank P<.001). Multivariable Cox hazard model demonstrated that patients with new PPI and low LVEF had higher 2-year cardiovascular mortality after TAVR (hazard ratio, 5.76; P<.001). CONCLUSION: New PPI following TAVR was not associated with overall survival or cardiovascular survival difference at 2 years. However, receiving a new PPI in the setting of low LVEF adversely impacts mid-term cardiovascular survival.


Assuntos
Estenose da Valva Aórtica/cirurgia , Ventrículos do Coração/fisiopatologia , Marca-Passo Artificial , Volume Sistólico/fisiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda/fisiologia , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , Seguimentos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/fisiopatologia
17.
Circ J ; 83(3): 672-680, 2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30700661

RESUMO

BACKGROUND: Patients with severe aortic stenosis (AS) and an extra-large annulus (ELA) area (>683 mm2) can rarely be treated by transcatheter aortic valve replacement (TAVR) because of the size limitation of the transcatheter heart valves. This study aimed to evaluate the feasibility of TAVR using a 29-mm SAPIEN3 (S3) valve in patients with ELA and S3-dimensions by post-procedural computed tomography (post-CT). Methods and Results: We included 261 patients undergoing TAVR using a 29-mm S3: 30 patients with ELA and 231 with non-ELA were identified. S3-dimensions were evaluated at the S3 inflow and annulus level by post-CT in 129 patients. The ELA group had a greater aortic annulus area measured by pre-procedural CT (737.3±54.7 vs. 578.4±41.9 mm2, P<0.0001), higher balloon inflation volume (36 vs. 33 mL, P<0.0001), a larger S3 area at inflow by post-CT (729.6±42.2 vs. 682.2±35.0 mm2, P<0.001), and a correlation between the inflation volume and S3 area (r=0.71, P=0.0005). No differences were observed between groups in paravalvular aortic regurgitation (PAR) ≥mild (43.3% vs. 27.6%, P=0.09), PAR ≥moderate (3.3% vs. 1.3%, P=0.39) or 1-year mortality (10.0% vs. 9.1%, P=0.87). CONCLUSIONS: TAVR using a 29-mm S3 with extra inflation of the delivery balloon can be considered as a treatment option for patients with severe AS and ELA.


Assuntos
Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Idoso de 80 Anos ou mais , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Feminino , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Desenho de Prótese , Resultado do Tratamento
18.
BMC Microbiol ; 18(1): 213, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30545294

RESUMO

BACKGROUND: VanB-type vancomycin (VAN) resistance gene clusters confer VAN resistances on Enterococcus spp. over a wide range of MIC levels (MIC = 4-1000 mg/L). However, the epidemiology and the molecular characteristics of the VAN susceptible VanB-type Enterococcus still remain unclear. RESULTS: We characterized 19 isolates of VanB-type Enterococcus faecium that might colonize in the gut and were not phenotypically resistant to VAN (MIC = 3 mg/L). They were obtained from two hospitals in Japan between 2009 and 2010. These isolates had the identical vanB gene cluster and showed same multilocus sequence typing (MLST) (ST78) and the highly related profiles in pulsed-field gel electrophoresis (PFGE). The vanB gene cluster was located on a plasmid, and was transferable to E. faecium and E. faecalis. Notably, from these VanB-type VREs, VAN resistant (MIC≥16 mg/L) mutants could appear at a frequency of 10- 6-10- 7/parent cell in vitro. Most of these revertants acquired mutations in the vanSB gene, while the remainder of the revertants might have other mutations outside of the vanB gene cluster. All of the revertants we tested showed increases in the VAN-dependent expression of the vanB gene cluster, suggesting that the mutations affected the transcriptional activity and increased the VAN resistance. Targeted mutagenesis revealed that three unique nucleotide substitutions in the vanB gene cluster of these strains attenuated VAN resistance. CONCLUSIONS: In summary, this study indicated that stealthy VanB-type E. faecium strains that have the potential ability to become resistance to VAN could exist in clinical settings.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Proteínas de Bactérias/metabolismo , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/classificação , Enterococcus faecium/isolamento & purificação , Humanos , Japão , Família Multigênica , Tipagem de Sequências Multilocus , Mutação , Vancomicina/farmacologia , Resistência a Vancomicina
19.
J Invasive Cardiol ; 30(11): 421-427, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30373952

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) in cases with left ventricular outflow tract calcification (LVOT-CA) remains a challenging procedure. The aim of this study was to compare the early outcomes of patients undergoing TAVR in LVOT-CA with new-generation devices vs early-generation devices. METHODS: Between January 2014 and December 2016, a total of 433 patients with severe aortic stenosis who had a preprocedural multidetector computed tomography underwent TAVR in a LVOT-CA. After propensity matching, data from 119 patients in each group were analyzed. TAVR endpoints and adverse events were defined according to the Valve Academic Research Consortium-2. RESULTS: Compared with early-generation devices (Edwards Sapien/Sapien XT/CoreValve), new-generation devices (Sapien 3/Evolut R) had significantly lower incidence of mild-moderate paravalvular leak (PVL) (1.7% new vs 7.6% early; P=.03), tended to have lower incidence of moderate or severe PVL (5.0% new vs 11.8% early; P=.06), had no significant difference in device success (89.1% new vs 83.2% early; P=.19), and had a significantly higher early safety rate at 30 days (93.3% new vs 84.9% early; P=.04). For cardiac conduction disturbances, new-generation and early-generation devices had similarly high rates of new permanent pacemaker implantation (16.8% new vs 15.1% early; P=.72), whereas the number of patients who developed new-onset left bundle-branch block (LBBB) were significantly higher in those with new-generation devices (16.0% new vs 6.7% early; P=.03). CONCLUSION: In the setting of LVOT-CA, patients with new-generation devices compared to those with early-generation devices had acceptable clinical outcomes except for cardiac conduction disturbances, especially in new-onset LBBB.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/patologia , Calcinose/cirurgia , Substituição da Valva Aórtica Transcateter/instrumentação , Obstrução do Fluxo Ventricular Externo/cirurgia , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico , Calcinose/complicações , Calcinose/diagnóstico , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/diagnóstico , Obstrução do Fluxo Ventricular Externo/etiologia
20.
Jpn J Ophthalmol ; 62(6): 699-705, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30324322

RESUMO

PURPOSE: Enterococcus faecalis causes severe acute endophthalmitis and often leads to poor visual outcomes. Conjunctival bacterial cultures occasionally grow atypical bacteria including E. faecalis, which can potentially contribute to the development of postoperative endophthalmitis. However, the characteristics of these ocular E. faecalis strains are unknown. This study is the first attempt to determine the population characteristics of E. faecalis clinical isolates from eye infections and ocular commensals. STUDY DESIGN: Retrospective METHODS: Twenty-eight E. faecalis ocular isolates were collected from 23 patients at 3 referring hospitals. The multilocus sequence typing (MLST) data were analyzed using the eBURST program. Phenotypes of cytolysin and gelatinase, antibiotic susceptibility, and mutations of the quinolone resistance-determining regions (QRDRs) of gyrA and parC were also examined. Pulsed-field gel electrophoresis (PFGE) was performed for strains from the same patients. RESULTS: PFGE revealed that 3 patients retained identical strains for 10 months to 2 and a half years. MLST identified 12 sequence types (STs), which were clustered into 3 clonal complexes (CCs) and 8 singletons, with ST179 the largest. Thirteen of the 23 isolates (56.5%) belonged to CC58, CC8, or CC2, which have previously been reported to be major CCs. Six of the 23 strains (26.0%) exhibited high-level quinolone resistance derived from mutations of the QRDRs in both gyrA and parC. CONCLUSIONS: The sequence types of E. faecalis ocular isolates were divergent, with no eye-specific lineages observed. Persistent colonization of E. faecalis on the ocular surface was demonstrated in patients with chronic ocular surface diseases.


Assuntos
DNA Bacteriano/análise , Endoftalmite/microbiologia , Enterococcus faecalis/genética , Infecções Oculares Bacterianas/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Idoso , Idoso de 80 Anos ou mais , Túnica Conjuntiva/microbiologia , Túnica Conjuntiva/patologia , Eletroforese em Gel de Campo Pulsado , Endoftalmite/diagnóstico , Enterococcus faecalis/isolamento & purificação , Infecções Oculares Bacterianas/diagnóstico , Feminino , Variação Genética , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA