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2.
Adv Sci (Weinh) ; 10(19): e2301876, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37096836

RESUMO

Determination of a reaction pathway is an important issue for the optimization of reactions. However, reactions in solid-state compounds have remained poorly understood because of their complexity and technical limitations. Here, using state-of-the-art high-speed time-resolved synchrotron X-ray techniques, the topochemical solid-gas reduction mechanisms in layered perovskite Sr3 Fe2 O7- δ (from δ ∼ 0.4 to δ = 1.0), which is promising for an environmental catalyst material is revealed. Pristine Sr3 Fe2 O7- δ shows a gradual single-phase structural evolution during reduction, indicating that the reaction continuously proceeds through thermodynamically stable phases. In contrast, a nonequilibrium dynamically-disordered phase emerges a few seconds before a first-order transition during the reduction of a Pd-loaded sample. This drastic change in the reaction pathway can be explained by a change in the rate-determining step. The synchrotron X-ray technique can be applied to various solid-gas reactions and provides an opportunity for gaining a better understanding and optimizing reactions in solid-state compounds.

3.
Pacing Clin Electrophysiol ; 45(10): 1194-1206, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35989415

RESUMO

INTRODUCTION: Pulmonary vein (PV) isolation (PVI) including the left atrial posterior wall (LAPW) (Box-PVI) is proposed as an additional strategy for non-paroxysmal atrial fibrillation (NPAF), however, the efficacy remains controversial. The more reliable and durable the Box-PVI we can create, the better the rhythm outcomes might be than with a conventional PVI alone. This study focused on the potential exit conduction of the box lesion and investigated whether the conventional Box-PVI would be sufficient. METHODS AND RESULTS: We enrolled 350 consecutive patients with NPAF that underwent a conventional encircling Box-PVI and examined whether latent exit conduction and dormant "exit" conduction independently remained on the LAPW and in the PVs using high frequency stimulation (HFS) and an adenosine triphosphate (ATP) injection. All electrograms inside the box lesion were eliminated in all cases, however, HFS inside the box propagated outward in 23 cases (6.6%) without any exit conduction by conventional burst stimulation, and 24 cases (6.9%) exhibited only dormant "exit" conduction of the LAPW. Additional ablation where positive HFSs were observed created a complete bidirectional Box-PVI in 43 (41.3%) of the cases without a first pass Box-PVI. The recurrence rates depended on the groups classified according to the HFS response. CONCLUSION: HFS delivered with an ATP injection on the LAPW and in the PVs following a Box-PVI could not only elucidate true exit block but also identified possible incomplete lesions or connections outside the ablation line, whose elimination could achieve a complete Box-PVI leading to a better rhythm outcome.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Fibrilação Atrial/cirurgia , Resultado do Tratamento , Ablação por Cateter/métodos , Veias Pulmonares/cirurgia , Adenosina , Trifosfato de Adenosina , Recidiva
5.
J Nippon Med Sch ; 88(4): 335-341, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32999179

RESUMO

BACKGROUND: This study sought to assess the efficacy of a deep-tissue thermal therapy system with a resonant cavity applicator (DTT-RCA), which safely heats deep joint tissue for treating osteoarthritis (OA) of the knee. METHODS: Two groups of participants were recruited. The DTT-RCA group comprised 20 knees. Kellgren-Lawrence (K-L) grade was I and II in 8 knees (DTT-RCA I/II group) [mean age 73.3 years (standard deviation 11.4) ], III and VI in 12 knees (DTT-RCA III/IV group) [75.4 (8.6) years]. The control group comprised 13 knees [68.2 (10.8) years]. K-L grade was I in 7 knees and II in 6 knees. This group received exercise therapy. The DTT-RCA I/II group and the control group were imaged by MRI T2 mapping at baseline and 6 months to determine the area of cartilage degeneration. RESULTS: Visual Analogue Scale improved only in the DTT-RCA I/II post-intervention (p < 0.01). Japanese Orthopedic Association knee rating scores (DTT-RCA I/II: p < 0.01, control group: p < 0.01), the Japanese Knee Osteoarthritis Measure (DTT-RCA I/II: p < 0.05, control: p < 0.01), and the Knee injury and Osteoarthritis Outcome Score (DTT-RCA I/II: p < 0.01, DTT-RCA III/IV: p < 0.05, control: p < 0.01) post-intervention. The magnitude of change did not differ significantly between the three groups. The area of cartilage degeneration did not change significantly post-intervention in the DTT-RCA I/II group, not even relative to the control group. CONCLUSIONS: This was the first study to test a DTT-RCA system in patients with knee OA. The system reduced the clinical symptoms of knee OA and could potentially be effective for conservative therapy.


Assuntos
Tratamento Conservador/métodos , Hipertermia Induzida/métodos , Osteoartrite do Joelho/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Articulação do Joelho , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Medição da Dor , Resultado do Tratamento , Escala Visual Analógica
6.
Odontology ; 109(1): 193-200, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32253625

RESUMO

PURPOSE: The aim of this study was to investigate root canal configurations in maxillary first and second molars from a Japanese population, as well as the relationship between the root canal number and root concavity depth, using micro-computed tomography. METHODS: Maxillary first (N = 74) and second (N = 70) molars from a Japanese population were used. Virtual horizontal sections were created, and the number of root canals and the degree of root concavity were measured. Mesiobuccal (MB) roots were categorized into Group 1 (with a single root canal) or Group 2 (with two or more root canals). The relationship between the root canal number and root concavity depth was evaluated using the Mann-Whitney U test. RESULTS: Approximately 51% and 35% of the MB roots in the three-rooted maxillary first and second molars, respectively, had two or more root canals. The depths of the root concavities in maxillary first molars differed significantly between Groups 1 and 2 at the mesial and distal sides of the MB root, in the section 2 mm apical to the furcation area (p < 0.05). CONCLUSIONS: A significant relationship between the number of root canals and the depth of root concavity in the MB root of the maxillary first molars was observed. Close clinical monitoring is needed during the removal of calculus and cleaning of the root surfaces of maxillary first molars: specifically, excessive removal of cementum and dentin should be avoided, particularly when the molar has already undergone root canal treatment.


Assuntos
Cavidade Pulpar , Dente Molar , Cavidade Pulpar/diagnóstico por imagem , Japão , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem , Microtomografia por Raio-X
7.
J Phys Ther Sci ; 32(12): 823-827, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33362353

RESUMO

[Purpose] Heat can prevent cartilage degeneration when applied to articular cartilage, but the size of the human knee joint makes it difficult to target cartilage during heat treatment. In this study, we aimed to establish a heat therapy method capable of safely applying heat to deep intra-articular tissues utilizing a resonant cavity applicator and to confirm the extent of cartilage heating in the human knee when using this system. [Participants and Methods] Heating experiments were carried out on the knees of healthy three volunteers using a resonant cavity applicator and a microwave diathermy system. After heat application, temperature distributions inside the knee were measured noninvasively using our measurement method based on ultrasound imaging techniques. [Results] We observed an increase in the temperature around the cartilage tissue in the knees of the volunteers using an ultrasonic thermometer; there was no increase in temperature in the overlying layers. During heating with up to 20 W of power, none of the volunteers experienced adverse reactions. [Conclusion] This study indicates the potential safety and effectiveness of the resonant cavity heat therapy system for knee osteoarthritis in a clinical setting.

8.
Phys Chem Chem Phys ; 22(42): 24181-24190, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33000816

RESUMO

Improvement of the low-temperature activity for NO oxidation catalysts is a crucial issue to improve the NOx storage performance in automotive catalysts. We have recently reported that the lattice oxygen species in SrFeO3-δ (SFO) are reactive in the oxidation of NO to NO2 at low temperatures. The oxidation of NO using lattice oxygen species is a powerful means to oxidize NO in such kinetically restricted temperature regions. This paper shows that Fe-site substitution of SFO with Mn or Co improves the properties of lattice oxygen such as the temperature and amount of oxygen release/storage, resulting in the enhancement of the activity for NO oxidation in a low-temperature range. In particular, NO oxidation on SrFe0.8Mn0.2O3-δ is found to proceed even at extremely low temperatures <423 K. From oxygen release/storage profiles obtained by temperature-programmed reactions, Co doping into SFO increases the amount of released oxygen owing to the reducibility of the Co species and promotes the phase transformation to the brownmillerite phase. On the other hand, Mn doping does not increase the oxygen release amount and suppresses the phase transformation. However, it significantly decreases the oxygen migration barrier of SFO. Substitution with Mn renders the structure of SFO more robust and maintains the perovskite structure after the release of oxygen. Thus, the oxygen release properties are strongly dependent on the crystal structure change before and after oxygen release from the perovskite structure, which has a significant effect on NO oxidation and the NOx storage performance.

9.
Arch Oral Biol ; 117: 104777, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32592930

RESUMO

OBJECTIVE: To clarify the fluoride/mineral kinetics in an oral biofilm following concurrent application of fluoride and other mineral ions released from experimental toothpaste containing S-PRG filler using depth-specific analysis. STUDY DESIGN: Twenty subjects wore in situ plaque-generating devices, comprised of a pair of enamel slabs, and a biofilm was allowed to form. The devices were removed after three days, immersed in the toothpaste filtrate containing Al, B, Sr and F ions for 1 min, and then reinserted at the same location. After 30 min, the devices were removed and samples were obtained by sectioning into outer, middle and inner biofilm layers (300-µm thick). Samples treated with filtrate containing F without S-PRG filler extract served as the control. Fluoride and the three other mineral ions extracted from 4-µm sections were quantified using a fluoride electrode and ICP-AES, respectively. The results were corrected for biomass volume, estimated by the area measurement of stained 2-µm sections. RESULTS: The mean uptake ratios (S-PRG/control, ng/mm3) of Al, B, Sr and F were 186.6/53.7, 58.4/25.0, 456.9/125.7 and 43.6/12.0, respectively, in the outer layer, indicating that the mineral ions could easily diffuse into the biofilm. F concentrations in the outer biofilm treated using filtrate with S-PRG filler extract were significantly higher than those in controls, although both biofilms were exposed to filtrates containing the same level of F. CONCLUSIONS: The results suggest that toothpaste containing S-PRG filler promotes fluoride retention in oral biofilms via the uptake of other mineral ions.


Assuntos
Biofilmes , Placa Dentária , Fluoretos/metabolismo , Cimentos de Ionômeros de Vidro/química , Minerais/metabolismo , Cremes Dentais/química , Esmalte Dentário , Placa Dentária/tratamento farmacológico , Humanos
10.
Phys Chem Chem Phys ; 22(22): 12368-12372, 2020 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-32373805

RESUMO

The structural characterization of a hardly-isolatable molybdenum-dinitrogen complex bearing a PNP-type pincer ligand, which is assumed to be a key reactive complex in the stoichiometric transformation of a molybdenum triiodide complex [MoI3(PNP)] into the corresponding molybdenum nitride complex under an atmospheric pressure of dinitrogen, was carried out by using dispersive XAFS.

11.
Arerugi ; 69(3): 204-208, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32435021

RESUMO

A 5-year-old girl living in Koriyama, Fukushima Prefecture was admitted in April with cough persisting for 1 month and fever. Chest X-ray showed diffuse ground-glass shadows in both lungs. After treatment with antibiotics, her fever went down on the 2nd day, and her cough subsided gradually. She was discharged on the 7th day, but her symptoms relapsed on the 8th day. Due to her worsening symptoms, she was readmitted on the 16th day. Chest CT scans showed enhancement of interstitial density. Serum anti-Trichosporon asahii antibody was positive. Her symptoms rapidly improved on a steroid regimen, and she was discharged on the 23th day. She was diagnosed as having summer-type hypersensitivity pneumonitis (SHP). She was instructed not to use a moldy humidifier and not to go to her grandmother's 57 years old wooden house. She has had no symptom after discharge. However, suspected mold was not found at her grandmother's house, and a provocation test there was negative. The HLA typing of the patient showed HLA-DQ8, which was previously described as SHP-sensitive.


Assuntos
Alveolite Alérgica Extrínseca/microbiologia , Umidificadores , Estações do Ano , Tricosporonose/etiologia , Anticorpos Antifúngicos/sangue , Pré-Escolar , Feminino , Humanos , Trichosporon
12.
J Cardiovasc Electrophysiol ; 30(12): 2743-2750, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31596017

RESUMO

BACKGROUND: Ethanol injections into the vein of Marshall (VOM) (EIM) are considered to be a good therapeutic option for atrial tachyarrhythmias, however, the safety remains to be determined. To elucidate what would affect the safety and potential complications of an EIM, we investigated the anatomical features of the VOM and patient background. METHODS: We performed the EIM before the conventional pulmonary vein isolation for drug-resistant atrial fibrillation in 88 patients and evaluated the anatomical features of the VOM and their background. RESULTS: All procedures were completed, however, other than myocardial staining, trivial contrast medium leaked out of the VOM into the pericardial space, that is, extravasation of contrast medium with capillary rupture, during the EIM in 20 patients (22.7%) regardless of the features of the VOM. No pericardial effusions requiring further intervention developed after the extravasation, which resolved by the next day on echocardiography in 18 of those patients. However, two patients who had extravasation other than during the initial contrast injection required additional therapeutic intervention for nonnegligible pericardial effusions. Their body weights were significantly lower and the latter two patients were also small lean women with heart failure and a preserved ejection fraction. CONCLUSIONS: The physical constitution, regardless of the characteristics of the VOM, could be strongly associated with adverse events during the EIM. We must take extreme care in smaller patients with poor compliant hearts during the EIM.


Assuntos
Técnicas de Ablação/efeitos adversos , Fibrilação Atrial/cirurgia , Vasos Coronários , Etanol/efeitos adversos , Complicações Pós-Operatórias/etiologia , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Peso Corporal , Etanol/administração & dosagem , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 2521-2524, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946410

RESUMO

We developed a resonant cavity applicator for noninvasive deep hyperthermia treatment of osteoarthritis. In previous studies, we confirmed its viability by heating agar phantoms and conducting computer simulations. To evaluate the heating performance of this system on human subjects, it is necessary to develop a new noninvasive temperature measurement system. In this study, we developed a new temperature measurement system utilizing ultrasound imaging techniques. After heating an agar phantom with our resonant cavity applicator, temperature measurements from both our custom-made noninvasive ultrasonic thermometer and an optical fiber thermometer were collected and compared. Both temperature distributions showed a reliable trend, with heat energy concentrated at the center of the agar phantom. Average error rates were less than 13% for temperatures. The results of this study describe the viability of the temperature measurement system and the resonant cavity applicator for clinical applications.


Assuntos
Temperatura Alta , Hipertermia Induzida , Ultrassonografia , Ágar , Desenho de Equipamento , Tecnologia de Fibra Óptica , Humanos , Imagens de Fantasmas , Termômetros
14.
J Thorac Dis ; 10(6): 3289-3297, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30069325

RESUMO

BACKGROUND: Lung cancer adjoining bullae (LC-AB) is an uncommon manifestation. The clinical characteristics and prognosis of LC-AB remain unclear. The aim of this study is to investigate the clinical features and overall survival (OS) of patients with LC-AB following lung resection compared to non-LC-AB group. METHODS: We retrospectively investigated 291 consecutive patients with lung cancer who underwent curative resection in a single institution between April 2007 and March 2015. A total of LC-AB was 52 patients. LC-AB was determined using thin slice computed tomography (CT) imaging and pathological findings. Survival analysis was calculated using the Kaplan-Meier method. We used a Cox proportional hazards model for the univariate and multivariate analysis to identify prognostic factors. RESULTS: The LC-AB group showed a higher frequency of younger patients (P=0.017), former or current smokers (P=0.011), men (P=0.021), tumor location in the upper lobe (P=0.031), moderately or poorly differentiated tumor histology (P<0.001), pleural indentation (P=0.007), and non-adenocarcinoma histology (P=0.016) than the non-LC-AB group. The 5-year survival and recurrence-free survival (RFS) rates were significantly higher in the LC-AB group than the non-LC-AB group (88.5% vs. 74.9%, P=0.010, 75.4% vs. 61.3%, P=0.030, respectively). Multivariate analysis using a Cox proportional hazard model of OS showed that LC-AB was an independent prognostic factor [hazard ratio (HR): 0.30, 95% confidence interval (CI): 0.12-0.77, P=0.012]. CONCLUSIONS: Patients with LC-AB had better OS than those with non-LC-AB. Thus, LC-AB may be an independent favorable prognostic factor following curative resection.

16.
J Am Chem Soc ; 140(1): 176-184, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29224338

RESUMO

The dynamic behavior of Rh species in 1 wt% Rh/Al2O3 catalyst during the three-way catalytic reaction was examined using a micro gas chromatograph, a NOx meter, a quadrupole mass spectrometer, and time-resolved quick X-ray absorption spectroscopy (XAS) measurements at a public beamline for XAS, BL01B1 at SPring-8, operando. The combined data suggest different surface rearrangement behavior, random reduction processes, and autocatalytic oxidation processes of Rh species when the gas is switched from a reductive to an oxidative atmosphere and vice versa. This study demonstrates an implementation of a powerful operando XAS system for heterogeneous catalytic reactions and its importance for understanding the dynamic behavior of active metal species of catalysts.

17.
Clin Case Rep ; 5(9): 1510-1515, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28878915

RESUMO

An EIM (ethanol infusion into the vein of Marshall [VOM]) provoked a fatal complication in a chronic hemodialysis patient. Autopsy revealed a lacerated VOM covered with thrombi as the only potential cause. The EIM caused vascular damage and clots resulting in myocardial necrosis and interstitial bleeding around the lacerated VOM.

18.
J Phys Chem Lett ; 8(11): 2368-2372, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28459582

RESUMO

We previously reported that small (∼1.2 nm) gold clusters stabilized by poly(N-vinyl-2-pyrrolidone) (Au:PVP) exhibited a localized surface plasmon resonance (LSPR) band at ∼520 nm in the presence of NaBH4. To reveal the mechanism of this phenomenon, the electronic structure of Au:PVP during the reaction with NaBH4 in air was examined by means of in situ X-ray absorption spectroscopy at Au L3-edge and UV-vis spectroscopy. These measurements indicated that the appearance of the LSPR band is not associated with the growth in size but is ascribed to electron doping to the Au sp band by the adsorbed H atoms.

19.
Phys Chem Chem Phys ; 19(21): 14107-14113, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28524189

RESUMO

This study proves that a small amount of Pd loading (1 wt%) on Sr3Fe2O7-δ can dramatically enhance the oxygen-storage properties of Sr3Fe2O7-δ. The topotactic oxygen intake and release between Sr3Fe2O6.75 and Sr3Fe2O6 takes place in response to gas switching between an O2 flow and H2 flow, regardless of the presence or absence of Pd loading. The effect of Pd loading is significant for the oxygen-release process under H2 atmosphere; that is, highly dispersed Pd metal nanoparticles sized less than 1 nm formed on Pd/Sr3Fe2O7-δ to promote H2 dissociation, resulting in the improvement of the oxygen-release temperature and rate. Pd/Sr3Fe2O7-δ with a layered perovskite structure has a higher oxygen-release property at lower temperature than Pd/SrFeO3-δ with a perovskite phase without the layered structure. These facts indicate that the surface reaction as well as the crystal structure are responsible for the oxide ion mobility in perovskite structure, and also provide guidelines for designing novel oxygen-storage materials.

20.
J Knee Surg ; 30(5): 467-473, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27680889

RESUMO

This prospective pilot study investigated whether grafting ß-tricalcium phosphate (B-TCP) into the bone-patellar tendon-bone (BPTB)-harvesting site after anterior cruciate ligament reconstruction would accelerate bone and tendon regeneration in the grafted site. Overall, 19 patients agreed prospectively to undergo regular morphological and histological examinations of the B-TCP-grafted site. Postoperative radiographic, ultrasonographic, and magnetic resonance imaging (MRI) examinations were performed to evaluate the grafted site at 1, 3, 6, and 12 months. Postoperative knee function and donor-site morbidity were assessed at 12 months using the kneeling test. A histological examination was also performed at this time Radiographic examination and MRI showed that the grafted B-TCP was completely absorbed and remodeled into normal bone structure in the tibia and patella at 6 months postoperatively. Histological and ultrasonographic examinations of all subjects showed that the grafted B-TCP was substituted by normal bone tissue, and the patellar tendon - bone junction had regenerated at 12 months postoperatively. Clinical functional knee tests showed good recovery of the donor site. All patients could perform kneeling and knee walking on hard ground. The results of this pilot study suggest that grafting B-TCP into the BPTB-harvesting site promotes the remodeling process of the bone and patellar tendon structures. This surgical treatment would decrease an incidence of the anterior knee pain after ACLR using a BPTB autograft.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Enxerto Osso-Tendão Patelar-Osso , Fosfatos de Cálcio , Sítio Doador de Transplante/cirurgia , Cicatrização/fisiologia , Adolescente , Adulto , Materiais Biocompatíveis , Regeneração Óssea/fisiologia , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Patela/fisiopatologia , Patela/cirurgia , Projetos Piloto , Estudos Prospectivos , Tíbia/fisiopatologia , Tíbia/cirurgia , Transplante Autólogo , Ferimentos e Lesões/fisiopatologia , Ferimentos e Lesões/cirurgia , Adulto Jovem
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