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1.
Chemistry ; 27(2): 785-793, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32996641

RESUMO

Generally, cage-shaped hosts for saccharides can bind strongly to guest molecules because of the three-dimensional preorganized hydrogen-bonding sites. However, the preparation of cage molecules is often difficult because of the low yield of the macrocyclization step. Here, we report a three-arm-shaped molecule possessing pyridine-acetylene-phenol units as a new kind of host having a preorganized three-dimensional hydrogen-bonding site. This three-arm-shaped host was readily prepared compared to a cage-shaped analogue. This host associated with lipophilic glycosides to form chiral complexes, and the association constants were sufficiently high as to be comparable to those of the cage-shaped analogue. Furthermore, this host extracted native monosaccharides into a lipophilic solvent.

2.
J Org Chem ; 83(6): 3132-3141, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29473751

RESUMO

Coordination cages were composed by self-organization of rigid C3 v-symmetric heptaarene tridentates and Pd(II) precursors. The heptaarene framework involves one mesitylene, three phenol, and three pyridine moieties, which were connected by Suzuki coupling reactions. The treatment of the tridentates with Pd(dppp)(OTf)2 or Pd(en)(NO3)2 in a 2:3 molar ratio furnished coordination cages, which was ascertained by crystallography, 1H NMR and DOSY measurements, and ESI-TOFMS and UV-vis spectra. The cages have six phenolic hydroxy groups inside and were expected to incorporate hydrogen-bonding guest molecules such as saccharides. CD and DOSY measurements showed that octyl hexoside guests could be incorporated into the cage.

3.
Br J Nutr ; 111(4): 625-32, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24073873

RESUMO

The consumption of probiotics by pregnant and lactating women may prevent the onset of allergic disorders in their children by increasing the concentrations of immunoactive agents such as cytokines in breast milk. Prebiotics such as fructo-oligosaccharides (FOS) increase the number of beneficial organisms such as bifidobacteria. Thus, prebiotics may have an effect similar to that of probiotics. The objective of the present study was to carry out a comprehensive analysis of mRNA expression in human milk cells to identify changes in the concentrations of cytokines in breast milk after the consumption of FOS (4 g × 2 times/d) by pregnant and lactating women. The microarray analysis of human milk cells demonstrated that the expression levels of five genes in colostrum samples and fourteen genes in 1-month breast milk samples differed more than 3-fold between the FOS and control groups (sucrose group). The mRNA expression level of IL-27, a cytokine associated with immunoregulatory function, was significantly higher in 1-month breast milk samples obtained from the FOS group than in those obtained from the control group. In addition, the protein concentrations of IL-27 in colostrum and 1-month breast milk samples were significantly higher in the FOS group than in the control group. In conclusion, the consumption of FOS by pregnant and lactating women increases the production of IL-27 in breast milk. Future studies will address the association of this phenomenon with the onset of allergic disorders in children.


Assuntos
Interleucina-27/metabolismo , Lactação/metabolismo , Leite Humano/metabolismo , Oligossacarídeos/farmacologia , Prebióticos , Gravidez/efeitos dos fármacos , Adulto , Método Duplo-Cego , Feminino , Humanos , Lactação/imunologia , Leite Humano/imunologia , Oligossacarídeos/imunologia , Gravidez/imunologia , Gravidez/metabolismo , RNA Mensageiro/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-31449013

RESUMO

The viscosity and the surface profile of a thixotropic gel were controlled via ultrasound vibrations. The ultrasound device consisted of two piezoelectric lead zirconate titanate transducers glued to each end of a 60-mm-long rectangular glass substrate. It generated a 71-kHz flexural standing wave along the length. A 0.9-mm-thick thixotropic gel film made from silicone oil and hydrophobic fumed silica was formed on the glass substrate. The ultrasound vibration decreased the film viscosity, and its surface profile could be changed by the acoustic radiation force acting from the gel to the surrounding air, generated by the flexural vibration of the substrate. The transient response of the surface profile was observed by switching the ultrasound excitation ON and OFF. When the excitation was switched OFF, the gel displacement gradually decreased, but the surface profile did not return to that of the initial steady state, indicating that the viscosity recovered in time to preserve the surface profile. When a pulsed megahertz (MHz) signal was used to control the gel deformation, the surface profile rapidly approached the initial steady-state profile after the excitation.

5.
ACS Appl Mater Interfaces ; 12(42): 47739-47746, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33047607

RESUMO

High-performance In-Ga-Zn-O (IGZO) Schottky diodes (SDs) were fabricated using hydrogenated IGZO (IGZO:H) at a maximum process temperature of 150 °C. IGZO:H was prepared by Ar + O2 + H2 sputtering. IGZO:H SDs on a glass substrate exhibited superior electrical properties with a very high rectification ratio of 3.8 × 1010, an extremely large Schottky barrier height of 1.17 eV, and a low ideality factor of 1.07. It was confirmed that the hydrogen incorporated during IGZO:H deposition increased the band gap energy from 3.02 eV (IGZO) to 3.29 eV (IGZO:H). Thus, it was considered that the increase in band gap energy (decrease in electron affinity) of IGZO:H contributed to the increase in the Schottky barrier height of the SDs. Angle-resolved hard X-ray photoelectron spectroscopy analysis revealed that oxygen vacancies in IGZO:H were much fewer than those in IGZO, especially in the region near the film surface. Moreover, it was found that the density of near-conduction band minimum states in IGZO:H was lower than that in IGZO. Therefore, IGZO:H played a key role in improving the Schottky interface quality, namely, the increase of Schottky barrier height, decrease of oxygen vacancies, and reduction of near-conduction band minimum states. Finally, we fabricated a flexible IGZO:H SD on a poly(ethylene naphthalate) substrate, and it exhibited record electrical properties with a rectification ratio of 1.7 × 109, Schottky barrier height of 1.12 eV, and ideality factor of 1.10. To the best of our knowledge, both the IGZO:H SDs formed on glass and poly(ethylene naphthalate) substrates achieved the best performance among the IGZO SDs reported to date. The proposed method successfully demonstrated great potential for future flexible electronic applications.

6.
Artigo em Inglês | MEDLINE | ID: mdl-30418873

RESUMO

This paper investigates acoustic levitation and noncontact transportation techniques for use with planar objects. An acoustic levitation system was developed which consists of a 1-mm-thick and 400-mm-long bending plate along with two bolt-clamped Langevin-type transducers (BLTs) that have stepped horns. A plane reflector was installed parallel to the vibrating plate to generate an ultrasound standing wave between the reflector and the plate. The sound pressure distribution in the ultrasound waveguide was calculated via finite-element analysis to investigate the effects of levitation of a planar object in the standing-wave field. A 1-mm-thick polystyrene plate was levitated along the nodal line of the acoustic standing wave in the waveguide. By controlling the driving phase difference between the two BLTs, the position at which flexural vibration occurs on the vibrating plate could be shifted along the length direction, and the trapped planar object could be moved by 9 mm along the same direction when the phase difference was varied from 0° to 360°.

7.
Nutrients ; 9(3)2017 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-28245628

RESUMO

Fructooligosaccharides (FOS) can selectively stimulate the growth of bifidobacteria. Here, we investigated the effect of maternal FOS ingestion on maternal and neonatal gut bifidobacteria. In a randomized, double-blind, placebo-controlled study, we administered 8 g/day of FOS or sucrose to 84 women from the 26th week of gestation to one month after delivery. The bifidobacteria count was detected using quantitative PCR in maternal (26 and 36 weeks of gestation) and neonatal (one month after delivery) stools. Maternal stool frequency was recorded from 24 to 36 weeks of gestation. The number of fecal Bifidobacterium spp. and Bifidobacterium longum in the FOS group was significantly higher than that in the placebo group at 36 weeks of gestation (2.7 × 1010/g vs. 1.1 × 1010/g and 2.3 × 1010/g vs. 9.7 × 108/g). In their neonates, these numbers did not differ between the groups. Also, stool frequency in the FOS group was slightly higher than that in the placebo group two weeks after the intervention (1.0 vs. 0.8 times/day), suggesting a potential constipation alleviation effect. In conclusion, the maternal FOS ingestion showed a bifidogenic effect in pregnant women but not in their neonates.


Assuntos
Bifidobacterium , Fezes/microbiologia , Prebióticos/administração & dosagem , Gravidez , DNA Bacteriano/isolamento & purificação , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Oligossacarídeos/administração & dosagem
8.
In Vitro Cell Dev Biol Anim ; 52(8): 799-805, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27251159

RESUMO

The main constituent of green tea, (-)-Epigallocatechin-3-O-gallate (EGCG), is known to have cancer-specific chemopreventive effects. In the present work, we investigated how EGCG suppresses cell adhesion by comparing the adhesion of human pancreatic cancer cells (AsPC-1 and BxPC-3) and their counterpart, normal human embryonic pancreas-derived cells (1C3D3), in catechin-containing media using organosilane monolayer templates (OMTs). The purpose of this work is (1) to evaluate the quantitativeness in the measurement of cell adhesion with the OMT and (2) to show how green-tea catechins suppress cell adhesion in a cancer-specific manner. For the first purpose, the adhesion of cancer and normal cells was compared using the OMT. The cell adhesion in different type of catechins such as EGCG, (-)-Epicatechin-3-O-gallate (ECG) and (-)-Epicatechin (EC) was also evaluated. The measurements revealed that the anti-adhesion effect of green-tea catechins is cancer-specific, and the order is EGCG≫ECG>EC. The results agree well with the data reported to date, showing the quantitativeness of the new method. For the second purpose, the contact area of cells on the OMT was measured by reflection interference contrast microscopy. The cell-OMT contact area of cancer cells decreases with increasing EGCG concentration, whereas that of normal cells remains constant. The results reveal a twofold action of EGCG on cancer cell adhesion-suppressing cell attachment to a candidate adhesion site and decreasing the contact area of the cells-and validates the use of OMT as a tool for screening cancer cell adhesion.


Assuntos
Catequina/análogos & derivados , Adesão Celular/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Catequina/administração & dosagem , Catequina/química , Linhagem Celular Tumoral , Humanos , Neoplasias Pancreáticas/patologia , Chá/química
9.
J Phys Chem B ; 120(7): 1221-7, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26845066

RESUMO

Adhesion of cancer cells with different metastatic potential and anticancer drug resistance has been quantitatively evaluated by using self-assembled monolayer (SAM)-patterned substrates and reflection interference contrast microscopy (RICM). Cell-adhesive SAM spots with optimized diameter could prevent cell-cell adhesion and thus allowed the systematic evaluation of statistically reliable numbers of contact area between single cancer cells and substrates by RICM. The statistical image analysis revealed that highly metastatic mouse melanoma cells showed larger contact area than lowly metastatic cells. We also found that both cancer cell types exhibited distinct transition from the "strong" to "weak" adhesion states with increase in the concentration of (-)-epigallocatechin gallate (EGCG), which is known to exhibit cancer preventive activity. Mathematical analysis of the adhesion transition revealed that adhesion of the highly metastatic mouse melanoma cells showed more EGCG tolerance than that of lowly metastatic cells. Moreover, time-lapse RICM observation revealed that EGCG weakened cancer cell adhesion in a stepwise manner, probably via focal adhesion complex. These results clearly indicate that contact area can be used as a quantitative measure for the determination of cancer phenotypes and their drug resistance, which will provide physical insights into the mechanism of cancer metastasis and cancer prevention.


Assuntos
Anticarcinógenos/farmacologia , Catequina/análogos & derivados , Adesão Celular/efeitos dos fármacos , Microscopia de Interferência/métodos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Catequina/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologia
10.
Gynecol Obstet Invest ; 58(1): 32-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15056993

RESUMO

Multi-minicore disease (MmD) is a congenital non-progressive or slowly progressive myopathy associated with multifocal degeneration of muscle fibers. Obstetric management for patients with MmD has not been described previously. A 25-year-old primigravida with a history of muscular weakness from birth was diagnosed with MmD and found to be susceptible to malignant hyperthermia (MH) by muscle biopsy at 28 weeks of gestation. Pregnancy proceeded uneventfully and she had a successful vaginal delivery under sufficient preparation for the possible occurrence of MH. Pregnant women who exhibit myopathic symptoms from childhood should consult an anesthesiologist prior to delivery.


Assuntos
Hipertermia Maligna/etiologia , Miopatias Congênitas Estruturais/diagnóstico , Complicações na Gravidez , Adulto , Biópsia , Cálcio/metabolismo , Cálcio/farmacologia , Feminino , Idade Gestacional , Humanos , Hipertermia Maligna/metabolismo , Hipertermia Maligna/patologia , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miopatias Congênitas Estruturais/complicações , Miopatias Congênitas Estruturais/patologia , NADH Tetrazólio Redutase/análise , Gravidez , Resultado da Gravidez , Fatores de Risco
11.
Radiology ; 231(3): 887-92, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15118120

RESUMO

PURPOSE: To measure both volume and signal intensity of the fetal lung at magnetic resonance (MR) imaging and to evaluate the clinical use of this method to predict fetal pulmonary hypoplasia. MATERIALS AND METHODS: A total of 87 fetuses evaluated with MR imaging at 24-39 weeks of gestation were classified into a control group with good respiratory outcome (group A, n = 58) or a poor outcome group with severe respiratory disturbance after birth (group B, n = 29). Planimetric measurement of total lung volume and calculation of the ratio of lung signal intensity to spinal fluid signal intensity (L/SF) were performed on MR images by using region-of-interest analysis. Regression analysis, analysis of covariance, analysis of variance, and receiver operating characteristic (ROC) analysis were performed. RESULTS: The best fit for group A lung volume was represented by the regression line V = (2.41 x G) - 37.6 (r = 0.537, P <.001), in which V is lung volume and G is gestational weeks; that for group B, by V = (0.97 x G) - 14.0 (r = 0.378, P <.05). Results of analysis of covariance with gestational weeks used as a covariate showed a significant difference in lung volume between the two groups (P <.001). Mean +/- SEM for L/SF ratio was 0.817 +/- 0.013 and 0.598 +/- 0.019 in groups A and B, respectively (P <.001). For prediction of postnatal respiratory outcome, the area under the ROC curve for lung volume and L/SF ratio combined was 0.990, significantly higher than that for lung volume alone (P <.05). CONCLUSION: Simultaneous measurement of fetal lung volume and signal intensity on MR images is a promising method for predicting fetal pulmonary hypoplasia.


Assuntos
Maturidade dos Órgãos Fetais , Pulmão/embriologia , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Idade Gestacional , Humanos , Recém-Nascido , Pulmão/patologia , Medidas de Volume Pulmonar , Curva ROC , Transtornos Respiratórios/diagnóstico , Transtornos Respiratórios/terapia , Respiração Artificial , Sensibilidade e Especificidade
12.
Pediatr Res ; 52(5): 687-91, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12409514

RESUMO

G protein beta3 subunit C825T polymorphism, which has previously been studied in association with common disorders in adults such as hypertension and obesity, has been focused upon recently for a possible important role in fetal metabolism. Japanese are characterized by having equal allele frequencies for this polymorphism. In this study, we determined the maternal and infantile genotypes in 342 pairs of normal healthy mothers and their infants, and compared the genotype frequencies with various infantile somatoscopic characteristics converted into SD units according to sex, parity and gestational weeks. We observed an association of the maternal (but not infantile) G protein beta3 subunit 825T allele with reduced head circumference but not with reduced birth weight of the neonate. No association was observed between G protein beta3 subunit C825T polymorphism and various maternal somatoscopic characteristics. Although detailed mechanism of this association requires further research, our results suggest that expression of the beta3 subunit 825T allele in the mother may exert influence on fetal metabolic environment, perhaps through changes in the maternal uterine environment, or on maternal metabolism.


Assuntos
Cabeça/anatomia & histologia , Proteínas Heterotriméricas de Ligação ao GTP/genética , Polimorfismo Genético , Adulto , Alelos , Substituição de Aminoácidos , Povo Asiático/genética , Peso ao Nascer , Cefalometria , Códon/genética , Feminino , Genótipo , Idade Gestacional , Humanos , Recém-Nascido , Japão , Mutação Puntual , Gravidez
13.
J Ultrasound Med ; 21(8): 841-7, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12164567

RESUMO

OBJECTIVE: To prepare nomograms for normal fetal lung volume using three-dimensional ultrasonography and to evaluate the possibility of clinical applications of this procedure. METHODS: One hundred twenty-five healthy neonates with birth weights within +/-1.5 SD (group A), 9 neonates with intrauterine growth restriction (birth weight less than -1.5 SD) but no severe respiratory disturbance at birth (group B), and 10 neonates with severe respiratory disturbance but no intrauterine growth restriction (group C) were studied. With the use of a three-dimensional ultrasonographic device, continuous B-mode images centering on the fetal thorax were acquired as volume data. Analytical software was used to repeatedly trace the contours of bilateral fetal lungs on transverse slices to calculate the lung volume. RESULTS: In group A, the total volume of normal fetal lungs can be expressed by the second-degree regression equation: 0.08 x (gestational week - 30.1)2 + 3.28 x gestational week - 67.2 (R = 0.909; P < .001). The lung volumes of groups B and C were below the 25th and 2.5th percentiles, respectively, of this regression curve. For the same case, the lung volume increased with gestational week in group B but remained unchanged or even decreased in group C. The total volume of normal fetal lungs can also be expressed by the linear regression equation: 0.02 x estimated fetal weight + 0.29 (R = 0.902). The lung volumes of groups B and C were distributed below and above, respectively, the 2.5th percentile of the regression line. CONCLUSIONS: This analytical method may be applied to evaluate lung development.


Assuntos
Pulmão/embriologia , Ultrassonografia Pré-Natal , Desenvolvimento Embrionário e Fetal , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Recém-Nascido , Medidas de Volume Pulmonar , Variações Dependentes do Observador , Gravidez
14.
Gynecol Obstet Invest ; 56(4): 218-20, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14614252

RESUMO

Ewing's sarcoma of the bone is a malignant bone tumor occurring mostly in adolescence and was considered to have poor prognosis. With recent advances in multi-agent combined chemotherapy, prognosis has improved, and more patients with primary lesions in the pelvis opt for limb-saving surgeries. In the present case, Ewing's sarcoma in the left pelvis was diagnosed at the age of 11 and the patient underwent multi-agent chemotherapy combined with limb-sparing hemipelvectomy. She became pregnant at the age of 22. After an uneventful pregnancy, she delivered a healthy child at 37 weeks of gestation by cesarean section because of pelvic distortion. This is the first reported case of pregnancy and delivery after limb-sparing hemipelvectomy due to Ewing's sarcoma. Since the multi-modality treatment improves survival, the number of women with Ewing's sarcoma who desire pregnancy is expected to increase in the future. This is a valuable case that will provide useful information for such patients.


Assuntos
Neoplasias Ósseas/cirurgia , Hemipelvectomia , Complicações na Gravidez , Resultado da Gravidez , Sarcoma de Ewing/cirurgia , Adulto , Índice de Apgar , Cesárea , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez
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