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1.
Comput Methods Programs Biomed ; 242: 107810, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769417

RESUMO

BACKGROUND AND OBJECTIVE: We used a 2D fluid-solid interaction (FSI) model to investigate the critical conditions for the arrest of the CTCs traveling through the narrowed capillary with a platelet attached to the capillary wall. This computational model allows us to determine the deformations and the progression of the passage of the CTC through different types of microvessels with platelet included. METHODS: The modeling process is obtained using the strong coupling approach following the remeshing procedure. Also, the 1D FE rope element for simulating active ligand-receptor bonds is implemented in our computational tool (described below). RESULTS: A relationship between the CTCs properties (size and stiffness), the platelet size and stiffness, and the ligand-receptor interaction intensity, on one side, and the time in contact between the CTCs and platelet and conditions for the cell arrest, on the other side, are determined. The model is further validated in vitro by using a microfluidic device with metastatic breast tumor cells. CONCLUSIONS: The computational framework that is presented, with accompanying results, can be used as a powerful tool to study biomechanical conditions for CTCs arrest in interaction with platelets, giving a prognosis of disease progression.


Assuntos
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Ligantes , Prognóstico , Mama/patologia , Capilares/patologia
2.
Shokuhin Eiseigaku Zasshi ; 64(1): 29-33, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-36858589

RESUMO

A simultaneous analytical method was developed for the determination of alkyl furans (Furan, 2-methylfuran, 3-methylfuran and 2,5-dimethylfuran) in processed foods by headspace-GC-MS. Single-laboratory validation data of furan, 2-methylfuran, 3-methylfuran and 2,5-dimethylfuran showed good precision and accuracy. The mean recoveries ranged from 92 to 116%, the intermediate precision (RSDi) ranged from 0.9 to 12.9%. The level of LOQ ranged from 0.5 to 1.2 µg/kg (coffee), from 3.5 to 4.1 µg/kg (soy sauce), from 0.4 to 1.3 µg/kg (other foods: clear apple juice, infant formula and baby food), respectively. This method has the sensitivity to detect low levels of furan and alkyl furans contaminated in various foods and is thus applicable to surveillance for risk management in food safety.


Assuntos
Alimento Processado , Furanos , Lactente , Humanos , Café , Inocuidade dos Alimentos
3.
Eur J Cardiothorac Surg ; 54(6): 1081-1084, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29733357

RESUMO

OBJECTIVES: This study aimed to elucidate the physiological feasibility of aortic valve neocuspidization (AVNeo) by comparing the aortic annulus dimensions between patients after AVNeo and patients with normal aortic valves. METHODS: From December 2010 to October 2017, we performed AVNeo for various aortic valve pathologies in 147 patients. Of these patients, the aortic annulus dimensions were measured in 25 patients who underwent AVNeo for aortic valve disease as follow-up examination and compared with those measured in 15 patients who had normal aortic valves. Measurements were recorded using electrocardiography-gated transthoracic echocardiography. RESULTS: No significant differences in the aortic annulus dimensions were observed between the patients who had undergone AVNeo and those who had normal aortic valves. In a cardiac cycle, the annulus area in the systolic phase was consistently larger than that in the diastolic phase, which was a physiological condition. CONCLUSIONS: The movement of the aortic annulus after AVNeo is comparable with that of the aortic annulus of a normal aortic valve. Thus, AVNeo can be regarded as a more physiological operation in that it maintains the characteristics of the aortic valve similar to those of a normal aortic valve.


Assuntos
Valva Aórtica , Ecocardiografia , Doenças das Valvas Cardíacas , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/anatomia & histologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Estudos de Casos e Controles , Feminino , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Orthop Sci ; 21(4): 507-511, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27067290

RESUMO

BACKGROUND: In the Great East Japan Earthquake, the Japanese Red Cross Ishinomaki Hospital played an important role as a principal referral center within the Ishinomaki region, one of the most severely affected areas in eastern Japan. The present study describes the patient population, clinical characteristics, and time courses of the medical problems observed at this hospital. METHODS: A retrospective survey of medical logs and records was conducted on the first 2 weeks after the earthquake to characterize orthopedic traumas and related disorders treated during this catastrophe. Patient number, severity of injuries, number of patients secondarily transported to the referral medical centers in the inland area, and the number of surgeries performed during the study period were investigated. RESULTS: Totally, 7686 patients visited the hospital. Of which, 1807 patients suffered from exogenous diseases, such as trauma, burns, crush syndrome, deep venous thrombosis, and infectious diseases. Patients who suffered from hypothermia were the most frequently seen within the first 2 weeks after the earthquake. Interestingly, most patients' conditions were not severe and required only simple treatments. Four patients (0.2% of patients with exogenous diseases) were secondarily transported to the referral medical centers in the inland area and only four patients were surgically treated because of a lack of available implants, surgical devices, and electric power supply. DISCUSSION AND CONCLUSIONS: The Great East Japan Earthquake and subsequent tsunami, which occurred during an early spring afternoon, resulted in a unique orthopedic patient population, which included few severely injured patients compared with numerous deaths. We believe that each coastal region hospital should develop its own emergency medical care system to address future tsunami events while considering their surrounding environment. The information described in the present study should be important for preparation toward future events involving massive earthquakes followed by tsunami disasters.


Assuntos
Terremotos , Incidentes com Feridos em Massa , Sistema Musculoesquelético/lesões , Tsunamis , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
6.
Appl Spectrosc ; 68(10): 1181-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25198653

RESUMO

Differences in the hydrogen-bonding states of methanol in polar and nonpolar solvents were studied by using the first overtone of O-H stretching vibrations observed in the near-infrared (NIR) band ranging from 7500 to 6000 cm(-1). To eliminate the absorption of solvents, NIR-inactive nonpolar solvents carbon tetrachloride (CCl4) and tetrachloroethylene (C2Cl4) were chosen, along with deuterium-substituted polar solvents acetone-d6, acetonitrile-d3, 1,4-dioxane-d8, and tetrahydrofuran (THF)-d8. The changes in the hydrogen-bonding states of methanol during mixing with the solvents were estimated using the extended molar absorption spectrum, which was defined as the concentration difference. The extended molar absorption spectra in different concentrations were decomposed into a finite number of independent factors using a multivariate curve resolution-alternating least squares calculation. Two and three such factors were sufficient to reproduce the extended molar absorption spectra for the nonpolar and polar solvents, respectively. The detailed assignments of each factor were estimated using the calculated loadings and scores. A similarity analysis was also applied to the extended molar absorption spectra of methanol and effectively quantified the deviation from the spectrum of pure methanol. The methanol and solvent affinities were also compared.


Assuntos
Metanol/química , Solventes/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Deutério , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos
7.
Anal Chem ; 85(9): 4289-95, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23574608

RESUMO

The common derivatization method of primary amino groups by 2,4,6-trinitrobenzene sulfonate (TNBS) was applied to the detection of free adducts of advanced glycation end-products (AGEs), in combination with liquid chromatography-tandem mass spectrometry-multiple reaction monitoring (LC-MS/MS-MRM). The proposed TNBS-MS method provided a surprisingly significant improvement of the detection of AGE-free adducts (e.g., by a factor of >1000 for methylglyoxal-derived hydroimidazolone) with a detection limit of 1.0 nM (10 fmol/injection volume), which was due to the high ionization efficiency of the derived trinitrophenol moiety and its hydrophobicity. With the aid of stable-isotope-labeled internal standard (MG-H1-d3), the convenient TNBS method that allowed the derivation of AGE-free adducts bearing amino groups under mild reaction conditions (30 mM, pH 8.5, 30 min, 30 °C) also permitted successive detection and quantification of five typical AGE-free adducts at nanomolar levels in rat plasma (50 µL) with high reproducibility (2-9% of RSD) and recovery (93-113%), using LC-MS/MS-MRM.


Assuntos
Produtos Finais de Glicação Avançada/análise , Ácido Trinitrobenzenossulfônico/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
8.
Artigo em Inglês | MEDLINE | ID: mdl-27857602

RESUMO

The contraction process of living Vorticella sp. has been investigated by image processing using a high-speed video camera. In order to express the temporal change in the stalk length resulting from the contraction, a damped spring model and a nucleation and growth model are applied. A double exponential is deduced from a conventional damped spring model, while a stretched exponential is newly proposed from a nucleation and growth model. The stretched exponential function is more suitable for the curve fitting and suggests a more particular contraction mechanism in which the contraction of the stalk begins near the cell body and spreads downwards along the stalk. The index value of the stretched exponential is evaluated in the range from 1 to 2 in accordance with the model in which the contraction undergoes through nucleation and growth in a one-dimensional space.

9.
Biophysics (Nagoya-shi) ; 8: 11-19, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-27857603

RESUMO

The contraction process of living Vorticella sp. in polymer solutions with various viscosities has been investigated by image processing using a high-speed video camera. The viscosity of the external fluid ranges from 1 to 5mPa·s for different polymer additives such as hydroxypropyl cellulose, polyethylene oxide, and Ficoll. The temporal change in the contraction length of Vorticella sp. in various macromolecular solutions is fitted well by a stretched exponential function based on the nucleation and growth model. The maximum speed of the contractile process monotonically decreases with an increase in the external viscosity, in accordance with power law behavior. The index values approximate to 0.5 and this suggests that the viscous energy dissipated by the contraction of Vorticella sp. is constant in a macromolecular environment.

10.
J Org Chem ; 72(13): 4970-3, 2007 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-17536862

RESUMO

We encountered a unique phenomenon of reaction velocity reversal during the silylation between mixed simple alcohols (A; AOH) and alpha- or beta-hydroxyketones (B; BOH). The present reaction system using anilinosilanes 1a [PhNH(TMS)] (TMS-A) and 1b [PhNH(TES)] (TES-A) with the catalytic TBAF (0.02 equiv) reagent showed that the order of silylation-velocity between the independent system and the mixed system was distinctively reversed [nu(A) > nu(B) approximately nu(B(mix)) > nu(A(mix))]. A total of seven examples indicate its high generality: AOH = linalool, 3-octanol; BOH = valeroin, benzoin, 5-hydroxy-4-methyl-3-undecanone. Time-dependent IR spectroscopy analysis rationally supported this speculation.

11.
J Chem Phys ; 124(4): 044903, 2006 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-16460208

RESUMO

Just after poly(N-isopropylacrylamide) (PNIPA) gels are immersed into hot water over the critical temperature, they undergo a two- or three-step shrinking accompanied with the whitening. The size of gels and the destination temperature were changed and their effects on the shrinking process of PNIPA gels were studied. The following important knowledge in the volume phase transition process of PNIPA gels was obtained. The first is the fact that the fraction of first shrinking is determined by the shrinking rate in the first shrinking stage. The second is the fact that PNIPA gels are divided into small parts by the pinning of density fluctuation in the final stage of the first shrinking and that the shrinking process of each small part undergoes in the secondary shrinking stage. The volume phase transition process of PNIPA gels is briefly discussed from the viewpoint of the scaling theory.


Assuntos
Resinas Acrílicas/química , Algoritmos , Géis/química , Transição de Fase , Sítios de Ligação , Simulação por Computador , Temperatura
12.
Exp Anim ; 54(1): 101-5, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15725687

RESUMO

A case of spontaneous malignant lymphoma in a Japanese macaque (Macaca fuscata) was pathologically, etiologically and virologically studied. Nasal cavity was involved in the neoplastic lesions in addition to lymphoid and visceral tissues. Histopathological analyses revealed the presence of neoplastic cells classified into histiocytic Hodgkin-like cells and Reed-Sternberg-like cells. Histiocytic Hodgkin-like cells were CD16+ and CD20+, and the CD16+ cells were also positive for simian Epstein-Barr virus (sEBV)-encoded early RNA transcripts. RS-like cells were negative for CD3, CD16 and CD20. Antibodies to early antigen of sEBV were detected, while antibodies to simian T-cell leukemia virus-1 were negative. The case may correspond to EBV-associated nasal type NK/T-cell lymphoma in humans rather than Hodgkin lymphoma.


Assuntos
Animais de Laboratório , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/veterinária , Linfoma de Células T/diagnóstico , Linfoma de Células T/veterinária , Macaca , Doenças dos Macacos/diagnóstico , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/veterinária , Animais , Antígenos CD20 , Infecções por Vírus Epstein-Barr/etiologia , Infecções por Vírus Epstein-Barr/patologia , Tecido Linfoide/patologia , Linfoma de Células T/etiologia , Linfoma de Células T/patologia , Masculino , Doenças dos Macacos/etiologia , Doenças dos Macacos/patologia , Cavidade Nasal/patologia , Neoplasias Nasais/etiologia , Neoplasias Nasais/patologia , Receptores de IgG , Vísceras/patologia
13.
Primates ; 44(3): 273-80, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12884118

RESUMO

We examined growth changes in concentrations of plasma insulin-like growth factor-1 (IGF-1) and testosterone, and somatometric parameters in two captive male agile gibbons from birth to about 4 years of age, to examine the evolution of growth patterns in primates. Plasma IGF-1 concentrations in agile gibbons generally increased with age with values ranging from 200 to 1100 ng/ml. The growth profiles in plasma IGF-1 in the gibbons were similar to those reported for chimpanzees. The highest concentrations of plasma testosterone (230 and 296 ng/dl) were observed within the first 0.3 years from birth, then the concentrations rapidly decreased and fluctuated below 100 ng/dl. Continuously higher IGF-1 concentrations were observed after 2.6 and 3.5 years of age. The profiles of plasma testosterone in these gibbons also resembled those of other primates including humans. However, their plasma testosterone levels in both neonate and adult stages (60 ng/dl) were lower than those reported for macaques and chimpanzees of respective stages. The obtained growth profiles of plasma IGF-1 and testosterone suggest that the adolescent phase starts around 2.6 or 3.5 years of age in male agile gibbons. The growth trend in many morphological parameters including body weight showed a linear increase without a significant growth spurt at approximately the onset of puberty. Head length and first digit length had reached a plateau during the study period. Brachial index, which indicates the relative length of forearm to upper arm, significantly increased gradually through the growth period. This result indicates that forearm becomes relatively longer than the upper arm with growth, which may be an evolutionary adaptation for brachiation.


Assuntos
Hylobates/crescimento & desenvolvimento , Fator de Crescimento Insulin-Like I/análise , Maturidade Sexual/fisiologia , Testosterona/sangue , Adaptação Fisiológica , Animais , Locomoção , Masculino
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