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1.
J Stroke Cerebrovasc Dis ; 26(5): 1144-1153, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28256416

RESUMO

BACKGROUND: Vertigo or dizziness is a common occurrence, but it remains a challenging symptom when encountered in the emergency department (ED). A diagnostic score for stroke with high accuracy is therefore required. METHODS: A single-center observational study (498 patients) was conducted. The predictor variables were derived from a multivariate logistic regression analysis with Akaike information criterion. The outcome was the occurrence of stroke. We evaluated the utility of a new diagnostic score (TriAGe+) and compared it with the ABCD2 score. RESULTS: The cohorts included 498 patients (147 with stroke [29.4%]). Eight variables were included: triggers, atrial fibrillation, male gender, blood pressure ≥140/90 mm Hg, brainstem or cerebellar dysfunction, focal weakness or speech impairment, dizziness, and no history of vertigo or dizziness or labyrinth or vestibular disease. We derived the TriAGe+ score from these variables. In the cohort, the prevalence of stroke increased significantly using the diagnostic score: 5.9% for a score of 0-4; 9.1% for 5-7; 24.7% for 8-9; and 57.3% for 10-17. At a cutoff value of 10 points, the sensitivity of the score was 77.5%, the specificity was 72.1%, and the positive likelihood ratio was 3.2. When the cutoff was defined as 5 points, the score obtained a high sensitivity (96.6%) with a good negative likelihood ratio (.15). The new score outperformed the ABCD2 score for the occurrence of stroke (C statistic, .818 versus .726; P < .001). CONCLUSIONS: The TriAGe+ score can identify the occurrence of stroke in patients with vertigo or dizziness presenting to the ED.


Assuntos
Técnicas de Apoio para a Decisão , Tontura/epidemiologia , Serviço Hospitalar de Emergência , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Triagem/métodos , Vertigem/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prevalência , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco
2.
Clin Radiol ; 69(6): 559-66, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24625689

RESUMO

AIM: To assess the relationship between thin-section computed tomography (CT) features of primary tumour and high preoperative serum carcinoembryonic antigen (CEA) levels that reportedly suggest poor prognoses in early-stage lung adenocarcinoma. MATERIALS AND METHODS: Two hundred and seventy-five consecutive patients who underwent resection of pathological stage I (T1-2aN0M0) adenocarcinomas with a maximum diameter of ≤ 3 cm (144 men, 131 women; mean age 67.8 years) were enrolled. CT features of the primary tumours and clinical characteristics of these patients were statistically evaluated to identify the factors associated with high serum CEA levels (>5 ng/ml). RESULTS: Eighty-one patients (29.5%) had high serum CEA levels. In univariate analysis, lower ground-glass opacity ratio (p < 0.001), lower tumour shadow disappearance rate (TDR: the ratio of tumour area in mediastinal window to that of lung window, p < 0.001), presence of notch (p = 0.015), and coexistence with bullae or honeycomb cysts (p < 0.001) were observed more frequently in the group with high serum CEA levels than that of the group with normal levels. TDR [odds ratio (OR) 0.984; 95% confidence interval (CI): 0.976-0.993; p < 0.001] and coexistence with bullae or honeycomb cysts (OR = 3.08; 95% CI: 1.55-6.12; p = 0.001) remained significant, even after adjusting patients' age, gender, and smoking status. CONCLUSIONS: Adenocarcinomas with lower TDR and coexisting with bullae or honeycomb cysts are associated with high preoperative serum CEA levels. Although some CEA elevations may be due to benign pulmonary diseases, such tumours are suspected to have poor prognoses, even for early-stage diseases.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Antígeno Carcinoembrionário/sangue , Neoplasias Pulmonares/diagnóstico por imagem , Adenocarcinoma/sangue , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Cuidados Pré-Operatórios , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
Int J Hyperthermia ; 26(5): 465-74, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20377361

RESUMO

PURPOSE: Although induction heating cancer therapy (IHCT) using magnetic nanoparticles can be a promising approach to treatment-less multi-nodular cancers, the objective requirement for successful clinical application has not clearly been elucidated. We intended to define objective heat doses suitable for IHCT, especially focusing on the sizes of liver cancer nodules. MATERIALS AND METHODS: Alternating magnetic fields were applied to three human pancreatic cancer cell lines, the intercellular space of those cell pellets were filled with magnetic nanoparticles, and confirmed the cytotoxic effect of IHCT. Subsequently, the temperatures of liver cancer nodules in IHCT were simulated using a computer software program and the required heat dose for various sized tumours were determined. RESULTS: Heating the cancer cells up to 50 degrees C for 10 min was sufficient for complete cell killing and the heat dose of 1.7 W/g(tumour) is required for 10 mm tumour. Larger tumours require a smaller heat dose, e.g. 20 mm and 40 mm tumours require 0.7 W/g(tumour) and 0.6 W/g(tumour), respectively, whereas smaller tumours require large amounts of heat, e.g. 5 mm and 1 mm tumours require 5.1 W/g(tumour) and 105 W/g(tumour), respectively. CONCLUSIONS: Integrating the presently available technologies, including high-quality magnetic nanoparticles (1000 W/g(material)) and effective drug delivery systems (1-2 mg(material)/g(tumour)), treatment of a 10 mm tumour seems possible. Since treatment of smaller tumours less than 5 mm require substantial heat dose, researchers involved in IHCT should target cancer nodules of 10 mm or more, and develop a heat delivery system providing a minimum of 1.7 W/g(tumour).


Assuntos
Temperatura Alta , Hipertermia Induzida/métodos , Neoplasias/terapia , Linhagem Celular Tumoral , Sobrevivência Celular , Simulação por Computador , Dextranos , Óxido Ferroso-Férrico , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Magnetismo , Nanopartículas de Magnetita , Nanopartículas , Neoplasias Pancreáticas/terapia
4.
Phys Med Biol ; 54(8): 2571-83, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19349659

RESUMO

Magnetic nanoparticles have recently been widely applied in the bio-medical field. Responding to the demand for a simple and sensitive magnetic assay system for bio-liquid samples, we employed a general-purpose superconducting quantum interference device (SQUID) magnetometer. Strips of filter paper were used as a liquid-specimen sample holder possessing a very small magnetic background signal. An aqueous solution of superparamagnetic iron-oxide nanoparticles (Resovist) was dropped in a tiny blot-like spot in the middle of the filter paper and the magnetization was measured. Magnetic moments of a dilution series of Resovist solutions versus the number of particles provided a linear graph, revealing that the magnetic moment per Resovist particle was 8.25 x 10(-17) emu. 1 x 10(5) cancer cells were incubated with Resovist, and the number of Resovist particles attached to the cell surface and surrounding a living cell was calculated to be 1.02 +/- 0.14 x 10(7) particles/cell. Our system using a commercial SQUID magnetometer should be more than enough to determine the number of magnetic nanoparticles biologically reacting with living cells, contributing to the application of magneto nanomaterials to the life-science field.


Assuntos
Magnetismo , Nanopartículas , Calibragem , Linhagem Celular Tumoral , Sobrevivência Celular , Filtração , Humanos , Papel , Sensibilidade e Especificidade
7.
J Magn Reson ; 135(1): 99-103, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9799682

RESUMO

This is a trial to simplize sequences to get the relaxation function f31(t), which is usually detected by the double- or triple-quantum filtered (DQF or TQF) NMR in an isotropic phase. The results indicate that only two phase cycling is needed to get the f31(t) function, which shows the advantage of S/N (signal-to-noise ratio) in a minimum acquisition time. The filtering of coherence levels in the creation time need not be limited to double- or triple-quantum coherences. An 87Rb signal from a 4% (w/w) agar powder in 500-mM RbCl solution is recorded at 130.9 MHz as a Larmor frequency using a Bruker MSL 400 spectrometer.


Assuntos
Aumento da Imagem , Espectroscopia de Ressonância Magnética/métodos , Soluções/química , Cloretos/química , Modelos Teóricos , Rubídio/análise , Rubídio/química
8.
Solid State Nucl Magn Reson ; 8(2): 123-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9203285

RESUMO

Lattice defects in a compound semiconductor, gallium-arsenide are evaluated by two-dimensional nutation nuclear magnetic resonance. Especially in the case of indium doped gallium-arsenide, analysis of the nutation patterns indicates that the electric field gradient exists in the whole crystal. Asymmetry parameters and quadrupolar coupling constants are determined as approximately 1.0 and 93 kHz, respectively. These results suggest that the whole crystal is under slight strain. Through this work, it is demonstrated that a two-dimensional nutation nuclear magnetic resonance is the useful method to investigate the lattice defects in gallium-arsenide.


Assuntos
Arsenicais/química , Gálio/química , Espectroscopia de Ressonância Magnética , Simulação por Computador , Cristalografia , Eletroquímica , Índio , Modelos Químicos , Conformação Molecular , Semicondutores
9.
J Membr Biol ; 77(2): 77-91, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6142960

RESUMO

Effects of the reagents suppressing or supporting axoplasmic microtubule assembly were studied on the Na ionic current of squid giant axons by perfusing the axon internally with the solution containing the reagent. Among the reagents suppressing the assembly, colchicine, vinblastine, podophyllotoxin, sulfhydryl reagents such as DTNB and NEM, and chaotropic anions such as iodide and bromide, were examined. These reagents reduced maximum Na conductance and shifted the voltage dependence of steady-state Na activation in a depolarizing direction along the voltage axis. They also made the voltage dependence less steep, but did not affect sodium inactivation appreciably. Effects on Na ionic current of reagents which support microtubule assembly (Taxol, DMSO, D2O and temperature) were opposite the effects of those agents suppressing assembly. At the same time, we demonstrated that after Na currents were partially reduced, they could be restored by internally perfusing the axon with a solution containing microtubule proteins, 260K proteins and cAMP under conditions favorable for microtubule assembly. For full restoration, it was found that the following conditions were necessary: (1) The microenvironment within the axon is suitable for microtubule assembly. (2) Tubulins incorporated into microtubules are fully tyrosinated at their C-termini. (3) A peripheral protein having a molecular weight of 260,000 daltons (260K protein) is indispensable. These results suggest that axoplasmic microtubules and 260K proteins in the structure underlying the axolemma play a role in generating Na currents in squid giant axons.


Assuntos
Axônios/fisiologia , Microtúbulos/fisiologia , Sódio/metabolismo , Alcaloides/farmacologia , Animais , Axônios/efeitos dos fármacos , Colchicina/farmacologia , Decapodiformes , Deutério/farmacologia , Óxido de Deutério , Dimetil Sulfóxido/farmacologia , Ácido Ditionitrobenzoico/farmacologia , Etilmaleimida/farmacologia , Microtúbulos/efeitos dos fármacos , Paclitaxel , Podofilotoxina/farmacologia , Temperatura , Tubulina (Proteína)/análise , Tubulina (Proteína)/metabolismo , Vimblastina/farmacologia , Água/farmacologia
10.
J Membr Biol ; 77(2): 93-9, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6708090

RESUMO

Effect of internal colchicine on asymmetrical displacement currents was studied by internally perfusing squid giant axons with a solution containing colchicine. It was found that (1) asymmetrical displacement currents were composed of two parts; colchicine-sensitive and colchicine-resistant; that (2) the colchicine-sensitive part had a definite rising phase while the colchicine-resistant one showed an instantaneous jump, followed by exponential decay; and that (3) the colchicine-sensitive part related to normal Na channels.


Assuntos
Axônios/efeitos dos fármacos , Colchicina/farmacologia , Sódio/metabolismo , Animais , Axônios/fisiologia , Decapodiformes , Microtúbulos/efeitos dos fármacos , Microtúbulos/fisiologia , Podofilotoxina/farmacologia , Vimblastina/farmacologia
12.
Biochim Biophys Acta ; 251(3): 303-13, 1971 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-11452870

RESUMO

In this article, we have extensively studied and discussed the magnetic properties of acidic ferric hemoglobin and its isolated chains. The magnetic susceptibility, EPR and optical spectra of those samples were measured in the temperature region below 77 degrees K. By the magnetic susceptibility measurements, it could be made clear that at an acidic pH value, both ferric hemoglobin and its isolated chains were constituted of a mixture of two spin states (high-spin state S = 5/2 and low-spin state S = 1/2) and the ratio of this mixture varied in each protein sample, but was independent of the temperature change below 77 degrees K. The co-existence of these two components could be ascertained by the observation of EPR spectra at liquid hydrogen temperature. Acidic ferric hemoglobin and its isolated chains exhibited the two components of EPR spectra which corresponded to their magnetic susceptibility, and it was found that the relaxation time of the low-spin state was longer than that of the high-spin state. The low-spin component of EPR spectra was almost undetectable at liquid nitrogen temperature. The three principal g values of this low-spin were gz = 2.80, gy = 2.20, and gx = 1.70. At alkaline pH values these low-spin components and the high-spin component of EPR spectra were displaced by the different low-spin spectra which corresponded to the ferric hemoglobin-hydroxide complex. It seems that the magnetic properties of the high-spin component are the same as the acidic ferric myoglobin, and the fine structure of the iron ion also seems to be same. Optical spectroscopy also gave similar magnetic properties which corresponded to the magnetic measurements.


Assuntos
Carboxihemoglobina/química , Hemoglobinas/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Hemoglobinas/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Conformação Proteica , Espectrofotometria , Termodinâmica
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