ABSTRACT
Recently, nanocarriers that transport bioactive substances to a target site in the body have attracted considerable attention and undergone rapid progression in terms of the state of the art. However, few nanocarriers can enter the brain via a systemic route through the blood-brain barrier (BBB) to efficiently reach neurons. Here we prepare a self-assembled supramolecular nanocarrier with a surface featuring properly configured glucose. The BBB crossing and brain accumulation of this nanocarrier are boosted by the rapid glycaemic increase after fasting and by the putative phenomenon of the highly expressed glucose transporter-1 (GLUT1) in brain capillary endothelial cells migrating from the luminal to the abluminal plasma membrane. The precisely controlled glucose density on the surface of the nanocarrier enables the regulation of its distribution within the brain, and thus is successfully optimized to increase the number of nanocarriers accumulating in neurons.There are only a few examples of nanocarriers that can transport bioactive substances across the blood-brain barrier. Here the authors show that by rapid glycaemic increase the accumulation of a glucosylated nanocarrier in the brain can be controlled.
Subject(s)
Blood Glucose/metabolism , Blood-Brain Barrier/metabolism , Brain/metabolism , Drug Carriers/pharmacokinetics , Animals , Brain/blood supply , Drug Carriers/metabolism , Female , Glucose/metabolism , Glucose Transporter Type 1/metabolism , Glycosylation , Humans , Mice, Inbred BALB C , Micelles , Microscopy, Confocal , Nanoparticles/metabolism , Neurons/metabolism , Polymers/chemistry , Polymers/metabolismABSTRACT
Strain, magnetization, dielectric relaxation, and unpolarized and polarized neutron diffraction measurements were performed to study the magnetic and structural properties of spinel Co_{1-x}V_{2+x}O_{4}. The strain measurement indicates that, upon cooling, ΔL/L in the order of â¼10^{-4} starts increasing below T_{C}, becomes maximum at T_{max}, and then decreases and changes its sign at T^{*}. Neutron measurements indicate that a collinear ferrimagnetic order develops below T_{C} and upon further cooling noncollinear ferrimagnetic ordering occurs below T_{max}. At low temperatures, the dielectric constant exhibits a frequency dependence, indicating slow dynamics. These results indicate the existence of an orbital glassy state at low temperatures in this nearly metallic frustrated magnet.
ABSTRACT
Numerous attempts have been made to realize crossed coupling between ferroelectricity and magnetism in multiferroic materials at room temperature. BiFeO3 is the most extensively studied multiferroic material that shows multiferroicity at temperatures significantly above room temperature. Here we present high-field experiments on high-quality mono-domain BiFeO3 crystals reveal substantial electric polarization orthogonal to the widely recognized one along the trigonal c axis. This novel polarization appears to couple with the domains of the cycloidal spin order and, hence, can be controlled using magnetic fields. The transverse polarization shows the non-volatile memory effect at least up to 300 K.
ABSTRACT
A high-speed polarizing microscope system combined with a 37 T pulse magnet has been developed. This system was applied to successfully visualize the field-induced collapse of charge-orbital ordering in a layered manganite La(1/2)Sr(3/2)MnO(4). Quantitative analyses of the obtained polarizing microscope images provided clear evidence of this transition in contrast to rather moderate changes in magnetization and magnetoresistance. The ability of this system to carry out quantitative analysis was further tested through the observation of Faraday rotation in a Tb(3)Ga(5)O(12) crystal. The Verdet constant determined from the polarizing images is in reasonable agreement with that in literature. Local intensity analyses of the images indicate that we can investigate magneto-optical signals within an accuracy of 0.85% in an area of 9.6 x 9.6 microm(2).
ABSTRACT
The dispersion of nanomaterials in solutions is of primary importance for the improvement of their processability, but it also provides a way to investigate phase behavior and to assemble nanostructures in solvents. Several methods based on different interactions have been developed to disperse carbon nanotubes, whereas little development has been made for their boron nitride nanotube (BNNT) counterparts. A direct way to obtain long-range ordering may be through spontaneous nematic ordering in solutions at sufficiently high concentrations of the nanomaterial fraction. Lyotropic nematics have been observed in various organic and inorganic systems. In this work, the strong interactions between DNA and BNNTs were exploited to fabricate high-concentration BNNTs aqueous solutions by a simple method, and then, for the first time, nematic ordered ensembles of BNNTs were obtained by filtration. It is proposed that a localized liquid-crystal phase appears during filtration, as the ordering trend for the BNNTs was found to depend on the concentration of the aqueous solutions of the BNNTs. Moreover, BNNTs were successfully localized on a predefined area by using a thiol-modified DNA-BNNT hybrid.
Subject(s)
Boron Compounds/chemistry , DNA/chemistry , Nanotubes/chemistry , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Models, Molecular , Molecular Conformation , Nanotubes/ultrastructureABSTRACT
Interleukin-10 (IL-10) and transforming growth factor-beta (TGF-beta) are well known anti-inflammatory cytokines. We have studied the effect of adenovirus-mediated IL-10 and TGF-beta gene delivery on the induction of Graves' hyperthyroidism in our mouse model that involves repeated injections of adenovirus expressing the thyrotropin receptor A subunit (AdTSHR). We first constructed adenoviruses encoding the two cytokines (AdIL10 and AdTGF(beta)) and confirmed expression by in vitro infection of COS cells. Susceptible BALB/c mice were injected twice with AdTSHR alone or together with AdIL10 or AdTGF(beta), and bled two weeks after the second immunization. Significantly elevated serum thyroxine levels were seen in 26% of mice immunized with AdTSHR and AdIL10 versus 61% with AdTSHR alone. Levels of thyroid stimulating antibody, but not nonstimulating antibody, were also decreased, and TSHR-specific splenocyte secretion of interferon-gamma in recall assays was impaired in mice treated with AdIL10. In contrast, AdTGF(beta) had little effect on hyperthyroidism. Overall, our findings demonstrate that gene delivery of IL-10, but not TGF-beta, suppresses the induction of Graves' hyperthyroidism in a mouse model. However, the effect of IL-10 is less powerful than we observed previously with T helper type 2-inducers including adenovirus expressing IL-4, Shistosoma mansoni infection or alpha-galactosylceramide.
Subject(s)
Autoantibodies/immunology , Graves Disease/immunology , Interleukin-10/immunology , Transforming Growth Factor beta/immunology , Adenoviridae/genetics , Animals , Antibodies/immunology , Female , Genetic Vectors/administration & dosage , Immunoglobulins, Thyroid-Stimulating/immunology , Interleukin-10/genetics , Mice , Mice, Inbred BALB C , Models, Animal , Protein Binding , Receptors, Thyrotropin/immunology , Thyroid Gland/immunology , Transduction, Genetic/methods , Transforming Growth Factor beta/geneticsABSTRACT
OBJECTIVE: Drinking ethanol stimulates the appetite, producing a positive energy balance. The mechanism by which ethanol regulates the appetite in the central nervous system, however, has not been fully understood. The aim of this study is to investigate the interaction of ethanol with the satiety effect of leptin, a hormone which suppresses the appetite in the hypothalamic region. DESIGN: : Leptin (7.5 micro g) or the same dose of phosphate buffer saline (PBS) was administered into the third ventricle (i.c.v.), 30 min after an intraperitoneal injection (i.p.) of ethanol (0.5 g/kg body weight) or the same dose of PBS. MATERIALS: Adult male Sprague-Dawley rats weighing 290-320 g were used. MEASUREMENTS: Food intake was measured 2, 12 and 24 h after leptin i.c.v. infusion. The tyrosine phosphorylation of signal transducer and activator transcription factor 3 (STAT3) in the hypothalamus was analyzed by Western blotting. RESULTS: The cumulative food intakes in the saline/leptin group (saline i.p.+leptin i.c.v.) were markedly reduced to about 45% of the saline/PBS group (saline i.p.+PBS i.c.v.) at 2, 12 and 24 h time points (P<0.05, 0.001, and 0.005, respectively). As compared with the saline/leptin group, those of the ethanol/leptin group (ethanol i.p.+leptin i.c.v.) were significantly increased to the level seen in the saline/PBS group at 12 and 24 h time points (P<0.05, and P<0.005 vs the saline/leptin group, respectively). Ethanol administration resulted in about a 50% reduction of the leptin-induced STAT3 tyrosine phosphorylation seen in the hypothalamic protein as compared to that of the saline/leptin group. CONCLUSION: These findings suggest that ethanol-induced enhancement of the appetite may, in part, result from leptin resistance transiently caused by ethanol to attenuate the leptin signal transduction.
Subject(s)
Central Nervous System Depressants/pharmacology , DNA-Binding Proteins/metabolism , Ethanol/pharmacology , Feeding Behavior/drug effects , Hypothalamus/metabolism , Leptin/pharmacology , Trans-Activators/metabolism , Animals , Blotting, Western , Eating/drug effects , Male , Phosphorylation , Rats , Rats, Sprague-Dawley , STAT3 Transcription FactorABSTRACT
To investigate the mechanism of severe impairment of insulin action in type B insulin resistance, we extracted IgG from the serum of a patient with type B insulin resistance (B-IgG) and analyzed the inhibiting effect of B-IgG not only on insulin signaling but also on IGF-I signaling in Chinese hamster ovary (CHO) cells expressing human insulin receptor or human IGF-I receptor. Preincubation with 1 mg/ml B-IgG prevented insulin-induced phosphorylation of insulin receptor and insulin receptor substrate-1 (IRS-1) but did not alter the IGF-I-induced phosphorylation of the IGF-I receptor and IRS-1. (125)I-insulin binding was inhibited by 93% after preincubation with B-IgG at 37 degrees C and was recovered up to 50% of the control value by acid washing. However, when cells were preincubated with B-IgG at 4 degrees C, the insulin binding completely recovered the control value by acid washing. (125)I-IGF-I binding was not altered by B-IgG preincubation. Immunoblot study revealed that the protein level of the insulin receptor was strongly decreased by preincubation with 1 mg/ml B-IgG at 37 degrees C, but never at 4 degrees C. The IRS-1 protein level did not change by B-IgG preincubation. In order to know the role of the insulin receptor internalization in the inhibiting effect of B-IgG, we employed CHO cells expressing mutant insulin receptors which do not undergo internalization (CHO-K1018R). B-IgG incubation of CHO-K1018R at 37 degrees C failed to decrease the protein level of the insulin receptor. The present data indicate that IgG from the diabetic patient with type B insulin resistance decreased insulin receptor protein level, probably due to the enhanced degradation rate of the insulin receptor, in which insulin receptor tyrosine kinase activity and internalization are required for this process. This effect of B-IgG was specific for the insulin receptor with no effect on either IGF-I receptor or IRS-1, as reflected by the IGF-I effectiveness on glycemic control in this patient.
Subject(s)
Antibodies/pharmacology , Protein-Tyrosine Kinases/metabolism , Receptor, Insulin/antagonists & inhibitors , Receptor, Insulin/immunology , Animals , Binding Sites , CHO Cells , Cricetinae , Female , Humans , Immunoglobulin G/pharmacology , Insulin/metabolism , Insulin/pharmacology , Insulin Receptor Substrate Proteins , Insulin-Like Growth Factor I/metabolism , Insulin-Like Growth Factor I/pharmacology , Middle Aged , Mutation , Phosphoproteins/metabolism , Phosphorylation/drug effects , Receptor, Insulin/genetics , Receptor, Insulin/metabolismABSTRACT
Magnetic domain structures of Nd(1/2)Sr(1/2)MnO3 were investigated by means of low-temperature Lorentz electron microscopy. On cooling, magnetic domain walls started to appear at 250 K, and they were oriented straight along the [100] and [110] directions. With a further decrease in temperature, the volume of each magnetic domain increased with discontinuous domain-wall jumps. A characteristic granular image was observed at around 140 K, near the charge-ordering transition temperature. We consider that this originated from ferromagnetic nanoclusters that appeared in the antiferromagnetic matrix.
ABSTRACT
The DF3/MUC1 mucin-like, transmembrane glycoprotein is aberrantly overexpressed in most human carcinomas. The MUC1 cytoplasmic domain interacts with the c-Src tyrosine kinase and thereby increases binding of MUC1 and beta-catenin. In the present work, coimmunoprecipitation studies demonstrate that MUC1 associates constitutively with the epidermal growth factor receptor (EGF-R) in human ZR-75-1 breast carcinoma cells. Immunofluorescence studies show that EGF-R and MUC1 associate at the cell membrane. We also show that the activated EGF-R phosphorylates the MUC1 cytoplasmic tail on tyrosine at a YEKV motif that functions as a binding site for the c-Src SH2 domain. The results demonstrate that EGF-R-mediated phosphorylation of MUC1 induces binding of MUC1 to c-Src in cells. Moreover, in vitro and in vivo studies demonstrate that EGF-R increases binding of MUC1 and beta-catenin. These findings support a novel role for EGF-R in regulating interactions of MUC1 with c-Src and beta-catenin.
Subject(s)
Antigens, Neoplasm/metabolism , Cytoskeletal Proteins/metabolism , ErbB Receptors/metabolism , Mucin-1/metabolism , Proto-Oncogene Proteins pp60(c-src)/metabolism , Trans-Activators , Humans , Microscopy, Fluorescence , Phosphorylation , Protein Binding , Tumor Cells, Cultured , beta CateninABSTRACT
We report a rare hair follicle nevus that occurred in a three-month-old Japanese boy with mild frontonasal dysplasia. It had been present since birth. Histologically, numerous tiny vellus hair follicles were found within the dermis. The constituent cells of these follicles showed the features of follicular germ cells under the electron microscope. The fibroblasts around the follicles were active and merged with the colloid substance. Many myofibroblasts were found in a collagenous stroma in the atrophic lesion of the frontonasal dysplasia.
Subject(s)
Nevus/diagnosis , Skin Neoplasms/diagnosis , Diagnosis, Differential , Forehead , Hair Follicle , Humans , Infant , Male , Nevus/pathology , Nevus/ultrastructure , Nose , Skin Neoplasms/pathology , Skin Neoplasms/ultrastructureABSTRACT
We report a case of ganglioneuroma in a 67-year-old woman who presented with an abnormal shadow at a medical examination. She was admitted and chest radiography disclosed a mass in the upper right mediastinum. We suspected a mediastinal tumor after chest CT, chest MRI and bronchofiberscopic examination, and so surgical treatment was performed. The histopathological diagnosis was ganglioneuroma. Ganglioneuroma is thought of as a children's disease and adult onset is rare. We reasoned that ganglioneuroma should be included among the mediastinal tumors in patients over 60.
Subject(s)
Ganglioneuroma/diagnosis , Mediastinal Neoplasms/diagnosis , Aged , Diagnosis, Differential , Female , Humans , Magnetic Resonance Imaging , Radiography, Thoracic , Tomography, X-Ray ComputedABSTRACT
Pr(1--x)CaxMnO(3) and Nd(1--x)SrxMnO(3) were investigated with three-photon difference frequency generation (DFG). This method allows one to determine both the crystalline and the magnetic symmetry. In the highly ordered low-temperature phase of Nd(0.50)Sr(0.50)MnO(3), a DFG contribution coupling simultaneously to antiferromagnetic and charge ordering was observed and used to reveal the formation of domains. Thus, magnetically induced three-photon processes are introduced into the fields of both nonlinear magneto-optics and colossal magnetoresistance as a powerful new method.
ABSTRACT
We examined the differences between the results of an automatic sleep analysis system and inspection decision. Subjects were 10 males (average age 21.6 years). One section consists of 20 s records. The sections that deviated from the algorithm could not be decided. Each sleep stage decided by automatic analysis was compared with the inspection decision. The agreement ratio of stage 3 was 91.6% in the highest, and followed by stage 2, stage 4, stage W and stage 1. The lowest was 62.5% for movement time. The total agreement ratio was 85.8%. The agreement ratios of the apnea index (AI) and the apnea hypopnea index (AHI) were relatively high, but for types of sleep apnea, agreement ratios require improvement.
Subject(s)
Electroencephalography/instrumentation , Electroencephalography/standards , Sleep Stages/physiology , Adult , Equipment Design , Humans , Male , Sleep Apnea Syndromes/diagnosis , Sleep, REM/physiology , Time FactorsABSTRACT
To investigate the situation and problems contingent to hypnotic use and withdrawal, we conducted a questionnaire of outpatients. Only 41% of the patients were satisfied with their sleep and 53% of the patients took hypnotics. As regards the period, 83% of users had used them for more than 1 year and 19% had used them for more than 10 years. Although 90% of patients perceived efficacy of hypnotics, 67% felt more or less anxious about hypnotic use. Sixty-seven per cent of patients had actually withdrawn from the drugs or decreased dosage before. More than half the patients' conditions worsened after the withdrawal or reducing dosage.
Subject(s)
Hypnotics and Sedatives/adverse effects , Substance Withdrawal Syndrome/epidemiology , Substance Withdrawal Syndrome/etiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Hypnotics and Sedatives/administration & dosage , Male , Middle Aged , Substance Withdrawal Syndrome/psychology , Surveys and QuestionnairesABSTRACT
In order to evaluate anti-human Fas antibody, we have established a new graft-versus-host disease (GVHD) model wherein splenocytes of human Fas transgenic mice (hFas-TgM) were transferred to immune-deficient SCID mice. In this model, although host SCID cells are not activated by or responsive to graft hFas-TgM cells, graft hFas-TgM cells are activated by and responsive to host SCID cells and thus cause GVHD symptoms. SCID mice that received hFas-TgM splenocytes had increased human Fas-positive lymphocytes in lymph nodes, decreased in body weight, and developed skin diseases, including rash and alopecia. Administration of novel anti-human Fas antibody HFE7A, which did not induce liver toxicity after administration to mice, decreased the level of the human Fas-positive lymphocytes, blocked the decrease of body weight, and suppressed development of skin diseases in this model. These results indicate that induction of apoptosis to activated graft cells with nontoxic anti-Fas antibody could reduce GVHD symptoms.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Graft vs Host Disease/therapy , fas Receptor/physiology , Acute Disease , Animals , Apoptosis , Chronic Disease , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, SCID , Mice, TransgenicABSTRACT
OBJECTIVE: To investigate the therapeutic effect of anti-Fas monoclonal antibody (Mab, RK-8) in collagen induced arthritis (CIA). METHODS: CD1F1 mice were immunized with bovine type II collagen to induce CIA and were treated with RK-8 intravenously. The effect of RK-8 was monitored by visual scoring. ELISA to detect serum anti-type II collagen antibody was performed on Day 47 and 70. Histopathological analysis was performed on Days 31 and 72. Digital micrography was performed on Day 72. RESULTS: RK-8 treatment almost completely prevented CIA. This suppressive effect continued after RK-8 was discontinued. RK-8 significantly suppressed the serum anti-type II collagen antibody level on Day 47. Histological analysis revealed that RK-8 significantly reduced joint histopathology, as determined by the infiltration of inflammatory cells and cartilage damage, consistent with digital micrography. CONCLUSION: Administration of anti-Fas Mab may be a useful therapeutic strategy for rheumatoid arthritis if used early in the disease.
Subject(s)
Antibodies, Monoclonal/pharmacology , Arthritis/immunology , Arthritis/therapy , Collagen , fas Receptor/immunology , Animals , Antibody Formation/immunology , Apoptosis/immunology , Arthritis/chemically induced , Disease Models, Animal , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Species Specificity , Synovial Membrane/pathology , Synovitis/chemically induced , Synovitis/immunology , Synovitis/therapy , Thymus Gland/immunology , Thymus Gland/pathologyABSTRACT
To investigate patient attitudes towards open disclosure of malignant disease, we conducted a questionnaire survey of 17 patients with malignant lung tumors, to whom the nature of their disease was revealed. The questionnaire used a 100 mm analog scale. Ten of the patients were treated by chemotherapy and their questionnaire results before and after treatment were compared. It was found that they were mostly satisfied about being truthfully informed and that, indeed, they were anxious to know their true diagnoses. They were also keen to have their true prognosis revealed, but not as much as the diagnosis. They also wished to be informed about treatment and its effects. These attitudes showed no marked changes resulting from the administration of chemotherapy, and we therefore concluded that chemotherapy itself had no influence on patients' feelings about disclosure. The questionnaire was well accepted and was useful in judging attitudes to open disclosure.