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PURPOSE: Leptomeningeal enhancement (LME) suggests leptomeningeal dissemination (LMD) of tumor cells, which is a complication of end-stage glioblastoma, and is associated with a poor prognosis. However, magnetic resonance imaging (MRI) occasionally indicates the disappearance of peri-brainstem LME after surgical resection of glioblastoma. Since preoperative LMD may affect treatment indications, we aimed to analyze the clinical significance of preoperative LME of the brainstem in glioblastoma. METHODS: We retrospectively collected clinical and radiological data from consecutive patients with glioblastoma and preoperative LME of the brainstem, who were treated at our hospital between 2017 and 2020. RESULTS: Among 112 patients with glioblastoma, nine (8%) showed preoperative LME of the brainstem. In comparison with tumors without LME, tumor size was significantly associated with the preoperative LME of the brainstem (p = 0.016). In addition, there was a trend toward significance for a relationship between deep tumor location and preoperative LME of the brainstem (p = 0.058). Notably, among six patients who underwent surgical resection for glioblastoma with LME of the brainstem, four showed significant radiological disappearance of the LME on postoperative MRI. This suggests that the LME did not result from LMD in these cases. Moreover, these four patients lived longer than would be expected from the presence of LMD. However, this LME disappearance was not observed after biopsy or chemoradiotherapy. CONCLUSIONS: These findings suggest that preoperative LME does not necessarily indicate the presence of untreatable LMD; moreover, LME may disappear after surgical tumor resection. Thus, transient preoperative LME could be attributed to other mechanisms, including impaired venous flow due to intratumoral arteriovenous shunts, which can be resolved by reducing the tumor burden.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/cirurgia , Glioblastoma/patologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Quimiorradioterapia , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/cirurgia , Tronco Encefálico/patologia , Neoplasias Encefálicas/patologiaRESUMO
A thermocell is an emerging alternative to thermoelectric devices and exhibits a high Seebeck coefficient (Se) due to the large change of solvation entropy associated with redox reactions. Here, the Se of p-chloranil radicals/dianions (CAË-/2-) in acetonitrile was drastically increased from -1.3 to -2.6 mV K-1 by the addition of ethanol, and the increment surpassed the estimation of the classical Born model with continuum solvent media. UV-vis spectroscopy and electrochemical measurements at various mixing ratios of acetonitrile to ethanol revealed that the strong hydrogen bonding between ethanol and oxygen atoms of CA2- forms a 4 : 1 solvent-ion pair, while the ethanol molecules binding to CA2- dissociate upon its oxidation to CAË-. The local solvation structures of CA2- are in good agreement with density functional theory. This order-disorder transition of the local solvation structure around the CAË-/2- ions produces a large entropy change and results in a large Se value. The tailored solvation structure of redox ions by hydrogen bonding is a versatile method applicable to a variety of redox pairs and solvents, contributing to the development of electrolyte engineering for thermocells.
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Background: A previous report suggested that functional status does not differ between patients who received tranexamic acid and those who received placebo within the early hours of intracerebral hemorrhage (ICH). Our pilot study tested the hypothesis that 2 weeks administration of tranexamic acid would contribute to functional improvement. Methods: Consecutive patients with ICH were administered 250 mg tranexamic acid 3 times a day continuously for 2 weeks. We also enrolled historical control consecutive patients. We collected clinical data that involved hematoma size, level of consciousness, and Modified Rankin Scale (mRS) scores. Results: Univariate analysis showed that the mRS score on day 90 was better in the administration group (P = 0.0095). The mRS scores on the day of death or discharge suggested a favorable effect of the treatment (P = 0.0678). Multivariable logistic regression analysis also showed that the treatment was associated with good mRS scores on day 90 (odds ratio [OR] = 2.81, 95% confidence interval [CI]: 1.10-7.21, P = 0.0312). In contrast, ICH size was associated with poor mRS scores on day 90 (OR = 0.92, 95% CI: 0.88-0.97, P = 0.0005). After propensity score matching, there was no difference in the outcomes between the two groups. We did not detect mild and serious adverse events. Conclusion: The study could not show the significant effect of 2 weeks administration of tranexamic acid on functional outcomes of ICH patients after the matching; however, suggested that this treatment is at least safe and feasible. A larger and adequately powered trial is needed.
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OBJECTIVE: To evaluate the relationship between the change of titer and adverse events after the third vaccination for COVID-19 among healthcare workers. DESIGN AND SETTING: This was a prospective cohort study, and the follow-up period was from December 2021 to November 2023. PARTICIPANTS: A total of 392 healthcare workers aged over 20 years who worked at the facility and wished to have vaccine antibody titers measured participated in this study. EXPOSURES: A third dose of BNT162b2 COVID-19 vaccine was administered to healthcare workers working at the hospital, and we evaluated the changes in antibody titers before and after the vaccine, as well as adverse reactions after vaccination. MAIN OUTCOMES AND MEASURES: The primary endpoints were adverse reactions within 7 days after the third dose of COVID-19 vaccine and the rate of increase in COVID-19 vaccine antibody titer at 4 weeks. RESULTS: A total of 392 people participated in the study, of whom 358 participants had their antibody titers measured before and after the booster vaccination. The overall IgG geometric mean was 609 U/mL (561-663) before booster vaccination and increased to 18,735 U/mL (17,509-20,049) at 4 weeks after vaccination (p < 0.001). Multivariate analysis showed no statistically significant relationship between the primary endpoints, such as a change in antibody titer due to the presence of fever after vaccination or a change in antibody titer due to swelling at the vaccination site. Factors affecting the rate of increase in antibody titer, evaluated as secondary endpoints, were suggested to be age (1.02 (95 % confidence interval (CI): 1.01-1.03)) and hypertension (0.66 (95 % CI: 0.47-0.93)). CONCLUSIONS AND RELEVANCE: In relation to the booster effect of the third dose of COVID-19 vaccination, there was no statistically significant difference in the presence of fever or use of antipyretic or other drugs.
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Vacinas contra COVID-19 , COVID-19 , Humanos , Adulto , Vacina BNT162 , Estudos Prospectivos , Vacinação , Febre , Anticorpos AntiviraisRESUMO
Thermocells are a thermoelectric conversion technology that utilizes the shift in an electrochemical equilibrium arising from a temperature difference. This technology has a long history; however, its low conversion efficiency impedes its practical usage. Recently, an increasing number of reports have shown drastic improvements in thermoelectric conversion efficiency, and thermocells could arguably represent an alternative to solid thermoelectric devices. In this Minireview, we regard thermocells as molecular systems consisting of successive molecular processes responding to a temperature change to achieve energy generation. Various molecular technologies have been applied to thermocells in recent years, and could stimulate diverse research fields, including supramolecular chemistry, physical chemistry, electrochemistry, and solid-state ionics. These research approaches will also provide novel methods for achieving a sustainable society in the future.
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Carbon nanotubes (CNTs) exhibit extremely high nanoscopic thermal/electrical transport and mechanical properties. However, the macroscopic properties of assembled CNTs are significantly lower than those of CNTs because of the boundary structure between the CNTs. Therefore, it is crucial to understand the relationship between the nanoscopic boundary structure in CNTs and the macroscopic properties of the assembled CNTs. Previous studies have shown that the nanoscopic phonon transport and macroscopic thermal transport in CNTs are improved by Joule annealing because of the improved boundary Van-der-Waals interactions between CNTs via the graphitization of amorphous carbon. In this study, we investigate the mechanical strength and thermal/electrical transport properties of CNT yarns with and without Joule annealing at various temperatures, analyzing the phenomena occurring at the boundaries of CNTs. The obtained experimental and theoretical results connect the nanoscopic boundary interaction of CNTs in CNT yarns and the macroscopic mechanical and transport properties of CNT yarns.
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We report the one-step fabrication of aligned and high-quality carbon nanotubes (CNTs) using floating-catalyst chemical vapor deposition (FCCVD) with controlled fluidic properties assisted by a gas rectifier. The gas rectifier consists of one-dimensional straight channels for regulating the Reynolds number of the reaction gas. Our computational fluid dynamics simulation reveals that the narrow channels of the gas rectifier provide steady and accelerated laminar flow of the reaction gas. In addition, strong shear stress is induced near the side wall of the channels, resulting in the spontaneous formation of macroscopic CNT bundles aligned along the direction of the gas flow. After a wet-process using chlorosulfonic acid, the inter-tube voids inherently observed in as-grown CNT bundles are reduced from 16 to 0.3%. The resulting CNT fiber exhibits a tensile strength of 2.1 ± 0.1 N tex-1 with a Young's modulus of 39 ± 4 N tex-1 and an elongation of 6.3 ± 0.6%. FCCVD coupled with the strong shear stress of the reaction gas is an important pre-processing route for the fabrication of high-performance CNT fibers.
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BACKGROUND: Partially thrombosed anterior inferior cerebellar artery (AICA) aneurysms are extremely rare; thus, no established therapeutic approach exists. CASE DESCRIPTION: We report a large, partially thrombosed AICA aneurysm and discuss its therapeutic nuances. The aneurysm was asymptomatic; therefore, we aimed to treat it through a minimally invasive procedure. The aneurysm was of fusiform type and the proximal neck of the aneurysm was positioned at midline in front of the brainstem. To approach the neck, posterior transpetrosal approach is recommended. However, this approach can be invasive; thus, we performed distal clipping of the aneurysm using transcondylar fossa approach with occipital artery-AICA bypass to avoid ischemia of the AICA territory. Although the size of the aneurysm initially increased, it subsequently decreased. CONCLUSION: This is a rare case report describing the long-term clinical course after distal clipping in detail. We showed that traditional microsurgical techniques can be applied to treat patients with new, minimally invasive treatment strategies.
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BACKGROUND: Movement disorders are rare in brain tumors. We describe a 45-year-old woman with hemichorea, a concomitant contralateral sphenoid ridge meningioma. CASE DESCRIPTION: The meningioma enlarged as her hemichorea worsened, and after meningioma resection, the hemichorea gradually subsided. N-isopropyl-p-[123I]-iodoamphetamine single-photon emission computed tomography performed preoperatively showed decreased regional cerebral blood flow (CBF) to the basal ganglia circuit ipsilateral to the tumor and, when repeated postoperatively, confirmed improved regional CBF. CONCLUSION: We propose that the enlarging sphenoid ridge meningioma had a remote effect on regional CBF and the thalamocortical motor center and that complex changes in the basal ganglia output may have caused the hemichorea.
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BACKGROUND: Olanzapine 10 mg is recommended for breakthrough chemotherapy-induced nausea and vomiting. However, there is a possibility that 5 mg can be expected to be sufficiently effective. We aimed to investigate the efficacy and safety of olanzapine 5 mg for breakthrough chemotherapy-induced nausea and vomiting. METHODS: A single-arm prospective trial of olanzapine 5 mg every 24 h for 72 h was conducted to treat breakthrough chemotherapy-induced nausea and vomiting in patients receiving carboplatinbased chemotherapy. The primary endpoint was total control (i.e., no emesis, no nausea, and no rescue medications) over 72 h. The secondary endpoints were early efficacy using the nausea scores at 30, 60, and 120 min after taking olanzapine from baseline and adverse events. RESULTS: Among 84 potentially eligible patients, 19 patients who took olanzapine for breakthrough chemotherapy-induced nausea and vomiting were examined. The total control rate was 32% (95% CI: 13- 57%), 65% (95% CI: 38-89%), 65% (95% CI: 38-89%), and 29% (95% CI: 10-56%) during 2-24, 24-48, 48-72 h, and overall period, respectively. The nausea scale significantly reduced after 30 min (P=0.0078), and the scale had been reduced by 67% from the baseline after 60 min. The adverse event of somnolence of any grade was observed in 13 (68%) patients, 6 (32%) of whom had grade 2 and 1 (5%) grade 3 somnolence. CONCLUSIONS: Olanzapine 5 mg did not show the expected effect on the complete disappearance of breakthrough chemotherapy-induced nausea and vomiting within 24 h.
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Antieméticos , Antineoplásicos , Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Benzodiazepinas/efeitos adversos , Carboplatina/efeitos adversos , Humanos , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Olanzapina/uso terapêutico , Estudos Prospectivos , Vômito/induzido quimicamente , Vômito/tratamento farmacológicoRESUMO
BACKGROUND: Although it is well known that internal carotid-posterior communicating artery (ICA-PcomA) aneurysms compress the oculomotor nerve and cause nerve palsy, cases of ICA-PcomA aneurysms splitting the oculomotor nerve are extremely rare. CASE DESCRIPTION: We present the rare case of an asymptomatic, growing, left-sided ICA-PcomA aneurysm that was confirmed to split the oculomotor nerve. We report the clinical course and discuss the underlying mechanism. The oculomotor nerve, which is an aggregate of multiple fibers, exhibits age-related loss of compactness in the arrangement of its nerve fibers. CONCLUSION: We speculate that injury to the nerve fibers by aneurysmal compression was avoided because of the rare phenomenon of splitting of the oculomotor nerve.
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Ethylated α-cyclodextrin (Et18-α-CD) is used as a host matrix for I-/I3- thermocells. Although Et18-α-CD is not soluble in water at ambient temperature, it becomes soluble by complexation of the I3- anion. Meanwhile, the complex is precipitated upon elevating the temperature. The change in thermo-responsive solubility of the I3-/Et18-α-CD complex increases the Seebeck coefficient (Se) of the thermocell up to 2.6 mV K-1. The underlying mechanism of the increased Se is elucidated by UV-vis spectroscopy, Raman spectroscopy, and electrochemical measurements. This result shows the temperature-dependent solubility changes of redox-active species as a potential means to improve the performance of electrochemical thermocells.
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Flexible, light-weight and robust thermoelectric (TE) materials have attracted much attention to convert waste heat from low-grade heat sources, such as human body, to electricity. Carbon nanotube (CNT) yarn is one of the potential TE materials owing to its narrow band-gap energy, high charge carrier mobility, and excellent mechanical property, which is conducive for flexible and wearable devices. Herein, we propose a way to improve the power factor of CNT yarns fabricated from few-walled carbon nanotubes (FWCNTs) by two-step method; Joule-annealing in the vacuum followed by doping with p-type dopants, 2,3,5,6-tetrafluo-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). Numerical calculations and experimental results explain that Joule-annealing and doping modulate the electronic states (Fermi energy level) of FWCNTs, resulting in extremely large thermoelectric power factor of 2250 µW m-1 K-2 at a measurement temperature of 423 K. Joule-annealing removes amorphous carbon on the surface of the CNT yarn, which facilitates doping in the subsequent step, and leads to higher Seebeck coefficient due to the transformation from (semi) metallic to semiconductor behavior. Doping also significantly increases the electrical conductivity due to the effective charge transfers between CNT yarn and F4TCNQ upon the removal of amorphous carbon after Joule-annealing.
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Radiation therapy is associated with the subsequent development of cerebral aneurysms; however, stereotactic radiosurgery (SRS)-associated aneurysm cases have not been well documented, with only 18 cases reported to date. We present a case of intracranial aneurysms with the rupture occurring 20 years after SRS for a growth hormone-producing pituitary adenoma. This is the first report of aneurysms diagnosed following transsphenoidal surgery and SRS for pituitary adenoma. We believe that the aneurysm reported here is a consequence of the SRS treatment, and thus this may be a very rare long-term complication following radiation treatments.
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Adenoma/radioterapia , Doenças das Artérias Carótidas/etiologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/radioterapia , Aneurisma Intracraniano/etiologia , Radiocirurgia/efeitos adversos , Adulto , Doenças das Artérias Carótidas/diagnóstico , Artéria Carótida Interna/patologia , Humanos , Aneurisma Intracraniano/diagnóstico , MasculinoRESUMO
BACKGROUND AND PURPOSE: Gastrointestinal bleeding is an important complication in the acute phase of hemorrhagic stroke. In this study, we aimed to identify the risk factors for gastrointestinal bleeding in patients with hemorrhagic stroke despite the administration of antiulcer drugs. METHODS: We conducted a retrospective cohort study of our hemorrhagic stroke cases. We analyzed the background factors associated with gastrointestinal bleeding in the study population and their outcomes. RESULTS: The study included 837 patients: 598 with intracerebral hemorrhages and 239 with subarachnoid hemorrhages. Among them, 22 patients developed gastrointestinal bleeding. Intraventricular hemorrhage (P=0.0019) and ongoing oral anticoagulant use (P=0.0177) were significantly associated with gastrointestinal bleeding. Gastrointestinal bleeding was significantly associated with severe disability at discharge (P=0.0333) and number of days of hospitalization (P=0.0190). CONCLUSIONS: The risk factors of poorly controlled gastrointestinal bleeding during the acute phase of hemorrhagic strokes were intraventricular hemorrhage and use of anticoagulant drugs. Patients with a high risk for gastrointestinal bleeding need to be identified and to be given effective prophylactic therapy. (Received October 12, 2017; Accepted March 29, 2018; Published August 1, 2018).
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Hemorragia Gastrointestinal/diagnóstico , Hemorragias Intracranianas/complicações , Acidente Vascular Cerebral/complicações , Anticoagulantes/efeitos adversos , Estudos de Coortes , Hemorragia Gastrointestinal/complicações , Humanos , Estudos Retrospectivos , Fatores de RiscoRESUMO
BACKGROUND: Thyroid-stimulating hormone-secreting pituitary adenomas (TSHomas) are uncommon, and majority of the patients present with symptoms of hyperthyroidism. Herein, we report the first case of TSHoma with differentiated thyroid carcinoma (DTC) that presented with visual disturbance without any clinical feature of hyperthyroidism. CASE DESCRIPTION: A 57-year-old man presented with left temporal hemianopsia of his left eye without any sign of hyperthyroidism. A mass lesion in the sellar and suprasellar region compressing the optic nerves was identified via magnetic resonance imaging. Free thyroxine and free triiodothyronine levels were slightly elevated, whereas the serum level of thyroid-stimulating hormone remained within normal range. Further endocrinologic examination led to the preoperative diagnosis of TSHoma. Ultrasonography and 111In-octreotide scan showed a mass lesion in left lobe of the thyroid gland, and subsequent thyroid aspiration biopsy confirmed the diagnosis of papillary thyroid carcinoma. After administration of short-acting octreotide to prevent thyrotoxic crisis in the perioperative period, the tumor was removed via endoscopic transnasal-transsphenoidal surgery, and the pathologic diagnosis of TSHoma was made. His visual acuity improved, and free triiodothyronine and free thyroxine levels normalized. He underwent thyroidectomy 3 months later after endoscopic transnasal-transsphenoidal surgery. CONCLUSIONS: Herein, we report the first case of TSHoma with DTC that presented with visual disturbance without any clinical feature of hyperthyroidism and reviewed the 13 reported cases of TSHoma coexisting with DTC. The optimal treatment strategy in patients with TSHoma and coexistent DTC has not been established, and individualized therapeutic strategies are needed.
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Adenoma/complicações , Neoplasias Hipofisárias/complicações , Câncer Papilífero da Tireoide/complicações , Tireotropina/metabolismo , Transtornos da Visão/complicações , Adenoma/diagnóstico por imagem , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos , Hipertireoidismo/complicações , Antígeno Ki-67/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico por imagem , Câncer Papilífero da Tireoide/diagnóstico por imagem , Transtornos da Visão/diagnóstico por imagemRESUMO
As a thermoelectric (TE) material suited to applications for recycling waste-heat into electricity through the Seebeck effect, poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) is of great interest. Our research demonstrates a comprehensive study of different post-treatment methods with nitric acid (HNO3) to enhance the thermoelectric properties of PEDOT:PSS. The optimum conditions are obtained when PEDOT:PSS is treated with HNO3 for 10 min at room temperature followed by passing nitrogen gas (N2) with a pressure of 0.2 MPa. Upon this treatment, PEDOT:PSS changes from semiconductor-like behaviour to metal-like behaviour, with a simultaneous enhancement in the electrical conductivity and Seebeck coefficient at elevated temperature, resulting in an increase in the thermoelectric power factor from 0.0818 to 94.3 µW m-1 K-2 at 150 °C. The improvement in the TE properties is ascribed to the combined effects of phase segregation and conformational change of the PEDOT due to the weakened coulombic attraction between PEDOT and PSS chains by nitric acid as well as the pressure of the N2 gas as a mechanical means.
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PURPOSE: We evaluated the effects of the highly selective phosphodiesterase type 5 inhibitor avanafil on electroretinogram and hemodynamics in dogs, and compared the effects with those of sildenafil. MATERIALS AND METHODS: Three experiments were performed in anesthetized dogs, including determination of the 1) influence on electroretinogram induced by a light adapted 30 Hz flicker stimulation, 2) direct hemodynamic changes and 3) potentiation of nitroglycerin induced hypotension. Avanafil was administered at doses that were pharmacologically equipotent to or higher than those of sildenafil for penile tumescence. RESULTS: 1) Intraduodenal doses of avanafil did not influence the electroretinogram waveform. In contrast, sildenafil changed the waveform shape and significantly delayed time to the peak of the electroretinogram positive waveform (vs vehicle p <0.05). 2) Intravenous infusion of avanafil or sildenafil (1 to 300 µg/kg per minute) significantly decreased systemic blood pressure, total peripheral resistance and pulmonary arterial pressure (vs vehicle p <0.05). Administration of sildenafil but not avanafil significantly decreased the resistance of common carotid and vertebral arteries (vs vehicle p <0.05). 3) Intraduodenal doses of avanafil or sildenafil (0.1 and 1 mg/kg) potentiated the AUC of nitroglycerin induced hypotension. However, the potentiating effect of avanafil at 1 mg/kg was significantly weaker than that of sildenafil (p <0.05). CONCLUSIONS: Data suggest that avanafil has a favorable safety profile for erectile dysfunction, which is attributable to its high inhibitory selectivity for phosphodiesterase type 5 against type 6 (retina) and 1 (vessels, etc), respectively, and its short acting pharmacodynamic property.