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1.
Sci Rep ; 11(1): 10750, 2021 05 24.
Article in English | MEDLINE | ID: mdl-34031431

ABSTRACT

The management of wavelength routed optical mesh networks is complex with many potential light path routes and numerous physical layer impairments to transmission performance. This complexity can be reduced by applying the ideas of abstraction from computer science where different equipment is described in the same basic terms. The noise-to-signal ratio can be used as a metric to describe the quality of transmission performance of a signal propagated through a network element and accumulates additively through a sequence of such elements allowing the estimation of end-to-end performance. This study aims to explore the robustness of the noise-to-signal ratio metric in an installed fibre infrastructure. We show that the abstracted noise-to-signal ratio is independent of the observers and their location. We confirm that the abstracted noise-to-signal ratio can reasonably predict the performance of light-paths subsequently set in our network. Having a robust network element abstraction that can be incorporated into routeing engines allows the network management controller to make decisions on the most effective way to use the network resources in terms of the routeing and data coding format.

2.
Oncogene ; 32(45): 5292-301, 2013 Nov 07.
Article in English | MEDLINE | ID: mdl-23318428

ABSTRACT

Shp2 is a positive regulator for Erk activation downstream of receptor tyrosine kinases for growth factors. It has been controversial how Shp2 induces Erk activation. We here demonstrate that EphA2 is responsible for Shp2-mediated Erk activation by phosphorylating Tyr542 and Tyr580 of Shp2 in the cells stimulated with growth factors. In NMuMG mammary epithelial cells stimulated with hepatocyte growth factor (HGF), HGF-dependent Erk phosphorylation was prolonged only in the presence of EphA2. This Erk activation paralleled the phosphorylation of Tyr542/580 of Shp2 and the association of Grb2 with Shp2, suggesting the positive signal involving Grb2 signal to activate Ras-Erk pathway. Immunohistochemical studies of mammary cancer specimens revealed that the cancer progression was associated with both Tyr580 phosphorylation of Shp2 and increased expression of EphA2, which were also correlated with increased Erk phosphorylation. Overexpression of either Shp2Thr468Met (a phosphatase-defective mutant found in Lentigines, Electrocardiographic abnormalities, Ocular hypertelorism, Pulmonary stenosis, Abnormal genitalia, Retardation of growth and sensorineural Deafness (LEOPARD) syndrome) or Shp2Asn308Asp (a phosphatase-active mutant found in Noonan syndrome) with EphA2 exhibited comparable activation of Erk and stronger activation than wild-type Shp2, suggesting the phosphatase-independent Erk activation. Expression of Shp2Thr468Met with Tyr542/580Phe mutations resulted in the suppression of Erk activation. Phosphatase-active and -inactive, and wild-type Shp2s bound equally to Grb2, suggesting that phosphorylation of Tyr542/580 of Shp2 was essential but not sufficient for Shp2-mediated Erk activation. We found that Gab1 (Grb2-associated binder 1) was involved in the mutant Shp2-mediated Erk activation. Zebrafish injected with Shp2Thr468Met mRNA showed cardiac edema, whereas those depleted of EphA2b showed less phenotype, suggesting that EphA2 might partly account for the phenotype of LEOPARD syndrome. Collectively, tyrosine phosphorylation of Shp2 by EphA2 contributes to the phosphatase-independent Shp2-mediated activation of Erk and might be involved in Shp2-associated diseases.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/metabolism , GRB2 Adaptor Protein/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Receptor, EphA2/metabolism , Animals , Edema, Cardiac , Enzyme Activation , Hepatocyte Growth Factor , Humans , LEOPARD Syndrome/genetics , LEOPARD Syndrome/metabolism , Noonan Syndrome/genetics , Noonan Syndrome/metabolism , Phosphorylation , Signal Transduction/genetics , Zebrafish
3.
Phys Chem Chem Phys ; 13(13): 6280-5, 2011 Apr 07.
Article in English | MEDLINE | ID: mdl-21359347

ABSTRACT

Photo-induced carrier processes at the heteromolecular interface of N,N'-dioctyl-3,4,9,10-perylenedicarboximide (PTCDI-C(8)) and quaterrylene (QT) on a molecular scale were examined by optical and photoelectron spectroscopy. The energy level alignments of the molecules were determined by X-ray photoelectron spectroscopy and the optical absorption spectra for detailed investigation of the photo-induced carrier process were analysed. A reduction in photoluminescence from PTCDI-C(8) on QT was observed, clearly demonstrating that the excitons generated in the PTCDI-C(8) layer are effectively dissociated at the heteromolecular interface. One important factor inducing this effective charge dissociation is the highly ordered molecular packing, which acts to increase the exciton diffusion length. Moreover, a specific increase in the photoluminescence excitation spectrum was observed around 3 eV, indicating that simultaneous exciton generation in both the QT and PTCDI-C(8) layers effectively suppresses such charge dissociation of the excitons. In other words, the existence of excitons in each molecule at the heteromolecular interface and HOMO-LUMO level alignment at the interface play an essential role in charge dissociation. Our results provide a striking insight into intermolecular interactions in the carrier process at the heteromolecular interface such as exciton generation, the recombination and dissociation processes, and the photovoltaic effect in organic semiconductors.

4.
J Chem Phys ; 133(21): 214703, 2010 Dec 07.
Article in English | MEDLINE | ID: mdl-21142310

ABSTRACT

Metal-organic interfaces based on copper-phthalocyanine monolayers are studied in dependence of the metal substrate (Au versus Cu), of its symmetry [hexagonal (111) surfaces versus fourfold (100) surfaces], as well as of the donor or acceptor semiconducting character associated with the nonfluorinated or perfluorinated molecules, respectively. Comparison of the properties of these systematically varied metal-organic interfaces provides new insight into the effect of each of the previously mentioned parameters on the molecule-substrate interactions.


Subject(s)
Copper/chemistry , Indoles/chemistry , Gold/chemistry , Halogenation , Isoindoles , Membranes, Artificial , Models, Molecular , Molecular Structure , Particle Size , Quantum Theory , Surface Properties
5.
J Biol Regul Homeost Agents ; 24(2): 157-65, 2010.
Article in English | MEDLINE | ID: mdl-20487629

ABSTRACT

We previously reported that 2-night/3-day trips to forest parks enhanced human NK activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that this increased NK activity lasted for more than 7 days after the trip in both male and female subjects. In the present study, we investigated the effect of a day trip to a forest park on human NK activity in male subjects. Twelve healthy male subjects, aged 35-53 years, were selected after giving informed consent. The subjects experienced a day trip to a forest park in the suburbs of Tokyo. They walked for two hours in the morning and afternoon, respectively, in the forest park on Sunday. Blood and urine were sampled in the morning of the following day and 7 days after the trip, and the NK activity, numbers of NK and T cells, and granulysin, perforin, and granzyme A/B-expressing lymphocytes, the concentration of cortisol in blood samples, and the concentration of adrenaline in urine were measured. Similar measurements were made before the trip on a weekend day as the control. Phytoncide concentrations in the forest were measured. The day trip to the forest park significantly increased NK activity and the numbers of CD16(+) and CD56(+) NK cells, perforin, granulysin, and granzyme A/B-expressing NK cells and significantly decreased CD4(+) T cells, the concentrations of cortisol in the blood and adrenaline in urine. The increased NK activity lasted for 7 days after the trip. Phytoncides, such as isoprene, alpha-pinene, and beta-pinene, were detected in the forest air. These findings indicate that the day trip to the forest park also increased the NK activity, number of NK cells, and levels of intracellular anti-cancer proteins, and that this effect lasted for at least 7 days after the trip. Phytoncides released from trees and decreased stress hormone levels may partially contribute to the increased NK activity.


Subject(s)
Affect , Killer Cells, Natural/immunology , Leisure Activities , T-Lymphocytes/immunology , Walking/physiology , Adult , Antigens, Differentiation, T-Lymphocyte/blood , Azepines/blood , Epinephrine/urine , Female , Flow Cytometry , Granzymes/blood , Humans , Hydrocortisone/blood , Leukocyte Count , Male , Middle Aged , Organometallic Compounds/blood , Perforin/blood , Trees
6.
Int J Immunopathol Pharmacol ; 22(4): 951-9, 2009.
Article in English | MEDLINE | ID: mdl-20074458

ABSTRACT

We previously reported that the forest environment enhanced human natural killer (NK) cell activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that the increased NK activity lasted for more than 7 days after trips to forests both in male and female subjects. To explore the factors in the forest environment that activated human NK cells, in the present study we investigate the effect of essential oils from trees on human immune function in twelve healthy male subjects, age 37-60 years, who stayed at an urban hotel for 3 nights from 7.00 p.m. to 8.00 a.m. Aromatic volatile substances (phytoncides) were produced by vaporizing Chamaecyparis obtusa (hinoki cypress) stem oil with a humidifier in the hotel room during the night stay. Blood samples were taken on the last day and urine samples were analysed every day during the stay. NK activity, the percentages of NK and T cells, and granulysin, perforin, granzyme A/B-expressing lymphocytes in blood, and the concentrations of adrenaline and noradrenaline in urine were measured. Similar control measurements were made before the stay on a normal working day. The concentrations of phytoncides in the hotel room air were measured. Phytoncide exposure significantly increased NK activity and the percentages of NK, perforin, granulysin, and granzyme A/B-expressing cells, and significantly decreased the percentage of T cells, and the concentrations of adrenaline and noradrenaline in urine. Phytoncides, such as alpha-pinene and beta-pinene, were detected in the hotel room air. These findings indicate that phytoncide exposure and decreased stress hormone levels may partially contribute to increased NK activity.


Subject(s)
Chamaecyparis , Killer Cells, Natural/drug effects , Plant Oils/administration & dosage , Administration, Inhalation , Adult , Affect/drug effects , Biomarkers/blood , Biomarkers/urine , CD3 Complex/analysis , Epinephrine/urine , Granzymes/blood , Humans , Killer Cells, Natural/immunology , Lymphocyte Count , Male , Middle Aged , Norepinephrine/urine , Perforin/blood , Plant Stems , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Vesicular Transport Proteins/blood , Volatilization
7.
Opt Express ; 16(26): 21321-32, 2008 Dec 22.
Article in English | MEDLINE | ID: mdl-19104562

ABSTRACT

A high-Q photonic crystal (PC) microcavity for TM-like modes, which can be applied to quantum cascade lasers (QCLs), was successfully designed in an air-hole based PC slab with semiconductor cladding layers. In spite of no photonic badgaps for TM-like modes in air-hole based PC slabs, cavity Q reached up to 2,200 by utilizing a graded square lattice PC structure. This is approximately 18 times higher than those previously reported for PC defect-mode microcavities for QCLs. This large improvement is attributed to a suppression of the coupling between the cavity mode and the leaky modes thanks to the dielectric perturbation in the graded structure. We also predicted a dramatic reduction of the threshold current in the designed cavity down to one-fifteenth of that of a conventional QCL, due to a decreased optical volume.

8.
J Biol Regul Homeost Agents ; 22(1): 45-55, 2008.
Article in English | MEDLINE | ID: mdl-18394317

ABSTRACT

We previously reported that forest bathing trips enhanced human NK activity, number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that the increased NK activity lasted for more than 7 days after the trip in male subjects. In the present study, we investigated the effect of forest bathing trip on human NK activity in female subjects. Thirteen healthy nurses, age 25-43 years, professional career 4-18 years, were selected with informed consent. The subjects experienced a three-day/two-night trip to forest fields. On day 1, the subjects walked for two hours in the afternoon in a forest field; on day 2, they walked for two hours each in the morning and afternoon in two different forest fields; and on day 3, the subjects finished the trip and returned to Tokyo after drawing blood and completing a questionnaire. Blood and urine were sampled on the second and third days during the trip, and on days 7 and 30 after the trip. NK activity, numbers of NK and T cells, and granulysin, perforin, and granzymes A/B-expressing lymphocytes in the blood samples, the concentrations of estradiol and progesterone in serum, and the concentrations of adrenaline and noradrenaline in urine were measured. Similar control measurements were made before the trip on a normal working day. The concentrations of phytoncides in the forests were measured. The forest bathing trip significantly increased NK activity and the numbers of NK, perforin, granulysin, and granzymes A/B-expressing cells and significantly decreased the percentage of T cells, and the concentrations of adrenaline and noradrenaline in urine. The increased NK activity lasted for more than 7 days after the trip. Phytoncides, such as alpha-pinene and beta-pinene were detected in forest air. These findings indicate that a forest bathing trip also increased NK activity, number of NK cells, and levels of intracellular anti-cancer proteins in female subjects, and that this effect lasted at least 7 days after the trip. Phytoncides released from trees and decreased stress hormone levels may partially contribute to the increased NK activity.


Subject(s)
Affect , Baths , Killer Cells, Natural/immunology , Nature , Adult , Epinephrine/urine , Estradiol/blood , Female , Humans , Japan , Leukocyte Count , Life Style , Norepinephrine/urine , Progesterone/blood , Surveys and Questionnaires , Time Factors
9.
Int J Immunopathol Pharmacol ; 21(1): 117-27, 2008.
Article in English | MEDLINE | ID: mdl-18336737

ABSTRACT

We previously reported that a forest bathing trip enhanced human NK activity, number of NK cells, and intracellular anti-cancer proteins in lymphocytes. In the present study, we investigated how long the increased NK activity lasts and compared the effect of a forest bathing trip on NK activity with a trip to places in a city without forests. Twelve healthy male subjects, age 35-56 years, were selected with informed consent. The subjects experienced a three-day/two-night trip to forest fields and to a city, in which activity levels during both trips were matched. On day 1, subjects walked for two hours in the afternoon in a forest field; and on day 2, they walked for two hours in the morning and afternoon, respectively, in two different forest fields; and on day 3, the subjects finished the trip and returned to Tokyo after drawing blood samples and completing the questionnaire. Blood and urine were sampled on the second and third days during the trips, and on days 7 and 30 after the trip, and NK activity, numbers of NK and T cells, and granulysin, perforin, and granzymes A/B-expressing lymphocytes in the blood samples, and the concentration of adrenaline in urine were measured. Similar measurements were made before the trips on a normal working day as the control. Phytoncide concentrations in forest and city air were measured. The forest bathing trip significantly increased NK activity and the numbers of NK, perforin, granulysin, and granzyme A/B-expressing cells and significantly decreased the concentration of adrenaline in urine. The increased NK activity lasted for more than 7 days after the trip. In contrast, a city tourist visit did not increase NK activity, numbers of NK cells, nor the expression of selected intracellular anti-cancer proteins, and did not decrease the concentration of adrenaline in urine. Phytoncides, such as alpha-pinene and beta-pinene were detected in forest air, but almost not in city air. These findings indicate that a forest bathing trip increased NK activity, number of NK cells, and levels of intracellular anti-cancer proteins, and that this effect lasted at least 7 days after the trip. Phytoncides released from trees and decreased stress hormone may partially contribute to the increased NK activity.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/biosynthesis , Cytotoxicity, Immunologic , Granzymes/biosynthesis , Killer Cells, Natural/immunology , Perforin/biosynthesis , Relaxation Therapy , Trees , Adult , Epinephrine/urine , Humans , Male , Middle Aged , Temperature
10.
J Phys Chem B ; 110(42): 20852-7, 2006 Oct 26.
Article in English | MEDLINE | ID: mdl-17048898

ABSTRACT

We have applied simultaneous horizontal and vertical bias to a single molecule (2 nm(2)) in an ordered and disordered matrix to virtually isolate and tune its property without taking it out physically from its environment. Using a dedicated electrode system, we have locally tuned nanoscale properties vertically by STM, while stabilizing its environment by applying a global electric field horizontally. Using this technique, we report tuning of molecular conformations in room temperature, whose evolution of states has been statistically investigated. We have also shown control on switching of a few selected conformations by applying dual bias simultaneously. As we avoid any direct injection of charge into the system via electrode contact, this technique could be used as a generalized method to tune phenomena evolved in an environment of weak interaction from a large distance without destroying the property.


Subject(s)
Electrochemistry/methods , Organic Chemicals/chemistry , Electrochemistry/instrumentation , Electrodes , Equipment Design , Methods , Molecular Conformation
11.
Histol Histopathol ; 21(1): 23-34, 2006 01.
Article in English | MEDLINE | ID: mdl-16267784

ABSTRACT

Alpha1-syntrophin, a scaffolding adapter and modular protein, is a cytoplasmic component of the dystrophin glycoprotein complex. This study investigated immunohistochemically the expression of alpha1-syntrophin in Duchenne and Fukuyama muscular dystrophies (DMD and FCMD, respectively). Biopsied muscles of five DMD, five FCMD, five normal controls and five disease controls (three myotonic and two facioscapulohumeral dystrophies) were analyzed. Immunoblot analysis showed that anti-alpha1-syntrophin antibody had a decreased reaction in both DMD and FCMD muscle extracts. Biopsied muscle sections and their serial sections were immunostained with rabbit anti-alpha1-syntrophin and rabbit anti-muscle-specific beta-spectrin antibodies, respectively. Immunoreactive patterns of sarcolemma were classified into (i) a continuously positive immunostaining pattern, (ii) a partially positive immunostaining pattern, (iii) a negative immunostaining pattern and (iv) a faint but entire surface positive immunostaining pattern. The group mean percentages of alpha1-syntrophin and beta-spectrin immunonegative myofibers in the DMD group were 39.3% and 10.8%, respectively, while those in the FCMD group were 45.5% and 10.4%, respectively. These values were statistically significant compared with those of disease control and normal control muscles. Thus we found that dystrophin-deficient DMD muscles contained significant numbers of alpha1-syntrophin-positive fibers and significant numbers of alpha1-syntrophin-negative fibers were present in dystrophin-positive muscles of severe muscular dystrophy such as FCMD. Alpha-dystrobrevin immunoreactivity was tested in DMD muscles and appreciable amounts of alpha-dystrobrevin that binds to syntrophin were found in DMD muscle membranes.


Subject(s)
Calcium-Binding Proteins/analysis , Membrane Proteins/analysis , Muscle Fibers, Skeletal/chemistry , Muscle Proteins/analysis , Muscular Dystrophies/congenital , Muscular Dystrophies/metabolism , Muscular Dystrophy, Duchenne/metabolism , Adolescent , Adult , Cell Membrane/chemistry , Child , Child, Preschool , Dystrophin-Associated Proteins/analysis , Female , Humans , Immunohistochemistry , Infant , Male , Middle Aged , Myofibrils/chemistry , Spectrin/analysis
12.
Virchows Arch ; 443(6): 761-7, 2003 Dec.
Article in English | MEDLINE | ID: mdl-12942324

ABSTRACT

This study was undertaken to investigate the expression of aquaporin 4 (AQP4) in the muscle plasma membrane of children with Fukuyama-type congenital muscular dystrophy (FCMD) at protein and mRNA levels. The biopsied six muscles with FCMD, six histochemically normal muscles and eight disease control muscles were analyzed by means of immunoblots, immunohistochemistry and reverse-transcription polymerase chain reaction (RT-PCR). Immunoblots showed that the band of FCMD muscle extracts stained with anti-AQP4 antibody was faint in comparison with that of normal muscle extracts. The immunohistochemistry revealed that most of the FCMD myofibers showed negative immunostaining with anti-AQP4 antibody, although the partially positive immunostaining of sporadic FCMD myofibers was noted. The immunoreactivity was positive with anti-dystrophin and anti-beta-spectrin antibodies in almost all FCMD myofibers. The quantitative RT-PCR demonstrated that the AQP4 mRNA level of the FCMD muscles was markedly reduced. On the basis of these findings, we conclude that the expression of AQP4 in FCMD myofibers is reduced and the reduced content of AQP4 mRNA in FCMD muscles may be related to the decreased expression of AQP4 at the muscle plasma membrane of FCMD myofibers.


Subject(s)
Aquaporins/genetics , Muscle, Skeletal/metabolism , Muscular Dystrophies/congenital , Muscular Dystrophies/metabolism , Aquaporin 4 , Humans , Immunoblotting , Immunohistochemistry , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction
13.
Microsc Res Tech ; 55(3): 154-63, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11747090

ABSTRACT

In order to investigate the mode of existence of the sarcoglycan complex, neuronal nitric oxide synthase (nNOS), beta-dystroglycan, and dystrophin in the normal skeletal myofiber, we examined the ultrastructural localization and mutual spatial relationship of nNOS, beta-dystroglycan, dystrophin, and the individual components of the sarcoglycan complex by using triple immunogold labeling electron microscopy. Each molecule of alpha-, beta-, gamma- and delta-sarcoglycans is located intracellularly or extracellularly near the muscle plasma membrane mostly in accordance with the sarcoglycan antigenic sites against which the antibodies were generated. The association of different two and/or three sarcoglycan molecules out of alpha-, beta-, gamma- and delta-sarcoglycan molecules was frequently observed. Each molecule of nNOS, beta-dystroglycan, and dystrophin was ultrastructurally noted along the cell surface of normal skeletal myofibers. Moreover, the close relation of a sarcoglycan molecule with beta-dystroglycan and dystrophin, and the association of nNOS with dystrophin were also confirmed ultrastructurally. Thus, this study demonstrated that the constituting molecules of the sarcoglycan complex, nNOS, beta-dystroglycan, and dystrophin existed in the form of a cluster at the normal muscle plasma membrane. The association of nNOS with dystrophin and its associated glycoproteins may form a macromolecular signaling complex at the muscle plasma membrane.


Subject(s)
Cytoskeletal Proteins/analysis , Dystrophin/analysis , Membrane Glycoproteins/analysis , Muscle, Skeletal/chemistry , Nitric Oxide Synthase/analysis , Amino Acid Sequence , Animals , Dystroglycans , Humans , Immunoblotting , Immunohistochemistry , Microscopy, Immunoelectron , Molecular Sequence Data , Nitric Oxide Synthase Type I , Rabbits , Sarcoglycans , Sheep
14.
Am J Physiol Heart Circ Physiol ; 281(5): H2133-42, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11668075

ABSTRACT

Rapid shortening of active cardiac muscle [quick release (QR)] dissociates Ca2+ from myofilaments. We studied, using muscle stretches and QR, whether Ca2+ dissociation affects triggered propagated contractions (TPCs) and Ca2+ waves. The intracellular Ca2+ concentration was measured by a SIT camera in right ventricular trabeculae dissected from rat hearts loaded with fura 2 salt, force was measured by a silicon strain gauge, and sarcomere length was measured by laser diffraction while a servomotor controlled muscle length. TPCs (n = 27) were induced at 28 degrees C by stimulus trains (7.5 s at 2.65 +/- 0.13 Hz) at an extracellular Ca2+ concentration ([Ca2+]o) = 2.0 mM or with 10 microM Gd3+ at [Ca2+]o = 5.2 +/- 0.73 mM. QR during twitch relaxation after a 10% stretch for 100-200 ms reduced both the time between the last stimulus and the peak TPC (PeakTPC) and the time between the last stimulus and peak Ca2+ wave (PeakCW) and increased PeakTPC and PeakCW (n = 13) as well as the propagation velocity (Vprop; n = 8). Active force during stretch also increased Vprop (r = 0.84, n = 12, P < 0.01), but Gd3+ had no effect (n = 5). These results suggest that Ca2+ dissociation by QR during relaxation accelerates the initiation and propagation of Ca2+ waves.


Subject(s)
Calcium/metabolism , Muscle Fibers, Skeletal/metabolism , Myocardial Contraction/physiology , Myocardium/cytology , Actin Cytoskeleton/physiology , Animals , Gadolinium/pharmacology , Membrane Potentials/drug effects , Membrane Potentials/physiology , Myocardium/metabolism , Rats , Rats, Sprague-Dawley
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