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1.
Phys Rev Lett ; 128(12): 127401, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394320

RESUMEN

Competition and cooperation among orders is at the heart of many-body physics in strongly correlated materials and leads to their rich physical properties. It is crucial to investigate what impact many-body physics has on extreme nonlinear optical phenomena, with the possibility of controlling material properties by light. However, the effect of competing orders and electron-electron correlations on highly nonlinear optical phenomena has not yet been experimentally clarified. Here, we investigated high-order harmonic generation from the Mott-insulating phase of Ca_{2}RuO_{4}. Changing the gap energy in Ca_{2}RuO_{4} as a function of temperature, we observed a strong enhancement of high order harmonic generation at 50 K, increasing up to several hundred times compared to room temperature. We discovered that this enhancement can be well reproduced by an empirical scaling law that depends only on the material gap energy and photon emission energy. Such a scaling law can hardly be explained by the electronic structure change in the single particle model and has not been predicted by previous theoretical studies on HHG in the simple Mott-Hubbard model. Our results suggest that the highly nonlinear optical response of strongly correlated materials is influenced by competition among the multiple degrees of freedom and electron-electron correlations.

2.
Science ; 376(6591): 397-400, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35446631

RESUMEN

Translational symmetry breaking is antagonistic to static fluidity but can be realized in superconductors, which host a quantum-mechanical coherent fluid formed by electron pairs. A peculiar example of such a state is the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, induced by a time-reversal symmetry-breaking magnetic field applied to spin-singlet superconductors. This state is intrinsically accompanied by the superconducting spin smecticity, spin density-modulated fluidity with spontaneous translational-symmetry breaking. Detection of such spin smecticity provides unambiguous evidence for the FFLO state, but its observation has been challenging. Here, we report the characteristic "double-horn" nuclear magnetic resonance spectrum in the layered superconductor Sr2RuO4 near its upper critical field, indicating the spatial sinusoidal modulation of spin density that is consistent with superconducting spin smecticity. Our work reveals that Sr2RuO4 provides a versatile platform for studying FFLO physics.

3.
Lett Appl Microbiol ; 52(5): 491-6, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21299580

RESUMEN

AIMS: The gram-positive bacterial genus Lactococcus has been taxonomically classified into seven species (Lactococcus lactis, Lactococcus garvieae, Lactococcus piscium, Lactococcus plantarum, Lactococcus raffinolactis, Lactococcus chungangensis and Lactococcus fujiensis). This study aimed to develop a novel multiplex polymerase chain reaction (PCR) primer set for the identification of the seven lactococcal species, as well as to differentiate the two industrially important dairy subspecies, L. lactis subsp. lactis and L. lactis subsp. cremoris. METHODS AND RESULTS: A multiplex PCR primer set was designed based on the nucleotide sequences of the 16S rRNA gene of the seven lactococcal species. The specificity of the established one-step multiplex PCR scheme was verified using more than 200 bacterial strains, in which a complete sequence match was confirmed by partial sequencing of their 16S rRNA gene. CONCLUSIONS: The one-step multiplex PCR enables the identification and speciation of bacterial strains belonging to the genus Lactococcus and the differentiation of strains of L. lactis subsp. lactis and L. lactis subsp. cremoris. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides an efficient method for identification of lactococcal strains of industrial importance.


Asunto(s)
Técnicas Bacteriológicas/métodos , Cartilla de ADN/genética , Lactococcus/genética , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Lactococcus/clasificación , Lactococcus lactis/clasificación , Lactococcus lactis/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Especificidad de la Especie
4.
J Dairy Sci ; 94(3): 1112-21, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21338777

RESUMEN

The poor survival of probiotic bacteria in commercial yogurts may limit their potential to exert health benefits in humans. The objective was to improve the survival of bifidobacteria in fermented milk. Cocultivation with some strains of Lactococcus lactis ssp. lactis improved the survival of bifidobacteria in fermented milk during refrigerated storage. Studies on one strain, Lc. lactis ssp. lactis MCC866, showed that the concentrations of dissolved oxygen were kept lower in the cocultivated fermented milk during storage compared with monocultured Bifidobacterium longum BB536 or samples cocultured with another noneffective Lc. lactis ssp. lactis strain. Degradation of genomic DNA was suppressed in the cocultivating system with Lc. lactis ssp. lactis MCC866. Several genes that participated in protection from active oxygen species (e.g., genes coding for alkyl hydroperoxide reductase and Fe(2+) transport system) were expressed at higher levels during refrigerated storage in Lc. lactis ssp. lactis MCC 866 compared with another noneffective Lc. lactis ssp. lactis strain. Concentration of free iron ion was also lower in supernatants of fermented milk cocultivated with B. longum BB536 and Lc. lactis ssp. lactis MCC866. These results suggest that Lc. lactis ssp. lactis MCC 866 is potentially superior in reducing oxygen damage and consequently improves the survival of bifidobacteria in the cocultivating system. This cocultivation system is of industrial interest for producing fermented milk containing viable bifidobacteria with long shelf life.


Asunto(s)
Bifidobacterium/crecimiento & desarrollo , Productos Lácteos Cultivados/microbiología , Viabilidad Microbiana , Bifidobacterium/metabolismo , Técnicas de Cocultivo , Manipulación de Alimentos/métodos , Lactococcus lactis/crecimiento & desarrollo , Simbiosis
5.
Clin Exp Immunol ; 161(2): 348-56, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20550546

RESUMEN

It has been suggested that alveolar and interstitial macrophages play a key role in the pathogenesis of idiopathic pulmonary fibrosis (IPF) by producing proinflammatory and/or fibrogenic cytokines. We showed that inflammatory macrophages expressed folate receptor beta (FRbeta) while resident macrophages in normal tissues expressed no or low levels of FRbeta. In the present study, we examined the distribution of FRbeta-expressing macrophages in the lungs of patients with usual idiopathic pulmonary fibrosis (UIP) and mice with bleomycin-induced pulmonary fibrosis (PF) and tested whether the depletion of FRbeta-expressing macrophages could suppress bleomycin-induced PF in mice. Immunostaining with anti-human or -mouse FRbeta monoclonal antibody (mAb) revealed that FRbeta-expressing macrophages were present predominantly in fibrotic areas of the lungs of patients with UIP and mice with bleomycin-induced PF. Intranasal administration of a recombinant immunotoxin, consisting of immunoglobulin heavy and light chain Fv portions of an anti-mouse FRbeta mAb and truncated Pseudomonas exotoxin A, increased survival significantly and reduced levels of total hydroxyproline and fibrosis in bleomycin-induced PF. In immunohistochemical analysis, decreased numbers of tumour necrosis factor-alpha-, chemokines CCL2- and CCL12-producing cells were observed in the immunotoxin-treated group. These findings suggest a pathogenic role of FRbeta-expressing macrophages in IPF. Thus, targeting FRbeta-expressing macrophages may be a promising treatment of IPF.


Asunto(s)
ADP Ribosa Transferasas/uso terapéutico , Toxinas Bacterianas/uso terapéutico , Bleomicina/farmacología , Proteínas Portadoras/inmunología , Exotoxinas/uso terapéutico , Inmunotoxinas/uso terapéutico , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Receptores de Superficie Celular/inmunología , Factores de Virulencia/uso terapéutico , ADP Ribosa Transferasas/administración & dosificación , ADP Ribosa Transferasas/genética , ADP Ribosa Transferasas/farmacología , Animales , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Toxinas Bacterianas/administración & dosificación , Toxinas Bacterianas/genética , Toxinas Bacterianas/farmacología , Proteínas Portadoras/metabolismo , Quimiocina CCL2/metabolismo , Exotoxinas/administración & dosificación , Exotoxinas/genética , Exotoxinas/farmacología , Receptores de Folato Anclados a GPI , Humanos , Hidroxiprolina/metabolismo , Fibrosis Pulmonar Idiopática/patología , Fragmentos de Inmunoglobulinas/genética , Inmunotoxinas/administración & dosificación , Inmunotoxinas/farmacología , Pulmón/metabolismo , Pulmón/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Quimioatrayentes de Monocitos/metabolismo , Fibrosis Pulmonar/patología , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/uso terapéutico , Análisis de Supervivencia , Factor de Crecimiento Transformador beta1/metabolismo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/metabolismo , Factores de Virulencia/administración & dosificación , Factores de Virulencia/genética , Factores de Virulencia/farmacología , Exotoxina A de Pseudomonas aeruginosa
6.
J Dairy Sci ; 93(5): 1815-23, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20412895

RESUMEN

Cultivation of bifidobacteria in milk is a difficult and industrially valuable task. In this paper, we report the finding of a novel technique to improve the growth of bifidobacteria in dairy products and the results of mechanism studies. The growth of bifidobacteria in skim milk medium was found to be stimulated upon cocultivation with certain strains of Lactococcus lactis ssp. lactis. Bifidobacterium growth-stimulating (BGS) activity was observed on a wide range of bifidobacterial species. Bifidobacterium growth-stimulating activity was associated with the ability to grow in skim milk medium and the presence of a cell wall-anchored proteinase (PrtP) in Lc. lactis ssp. lactis. Studies on one strain, Lc. lactis ssp. lactis MCC857, showed that crude PrtP extracts and casein hydrolysates exhibited BGS activity. The casein hydrolysate BGS activity was found in the low molecular weight fraction by HPLC separation. A combination of 2 AA, Met and Leu, was found to account for a large portion of the casein hydrolysate BGS activity. In conclusion, this cocultivation system is highly efficient and industrially applicable for the production of fermented milk with high cell counts of bifidobacteria.


Asunto(s)
Bifidobacterium/crecimiento & desarrollo , Productos Lácteos Cultivados/microbiología , Lactococcus lactis/crecimiento & desarrollo , Animales , Proteínas Bacterianas/metabolismo , Bifidobacterium/metabolismo , Leche/microbiología
7.
Br J Cancer ; 100(2): 344-51, 2009 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-19127263

RESUMEN

Mucin 4 (MUC4) is a high molecular weight transmembrane mucin that is overexpressed in many carcinomas and is a risk factor associated with a poor prognosis. In this study, we show that the DNA methylation pattern is intimately correlated with MUC4 expression in breast, lung, pancreas and colon cancer cell lines. We mapped the DNA methylation status of 94 CpG sites from -3622 to +29 using MassARRAY analysis that utilises base-specific cleavage of nucleic acids. MUC4-negative cancer cell lines and those with low MUC4 expression (eg, A427) were highly methylated near the transcriptional start site, whereas MUC4-positive cell lines (eg, NCI-H292) had low methylation levels. Moreover, 5-aza-2'-deoxycytidine and trichostatin A treatment of MUC4-negative cells or those with low MUC4 expression caused elevation of MUC4 mRNA. Our results suggest that DNA methylation in the 5' flanking region play an important role in MUC4 gene expression in carcinomas of various organs. An understanding of epigenetic changes in MUC4 may contribute to the diagnosis of carcinogenic risk and prediction of outcome in patients with cancer.


Asunto(s)
Islas de CpG , Metilación de ADN , Mucina 4/genética , Neoplasias/genética , Regiones Promotoras Genéticas/genética , Acetilación , Azacitidina/análogos & derivados , Azacitidina/farmacología , Línea Celular Tumoral , Metilasas de Modificación del ADN/antagonistas & inhibidores , ADN de Neoplasias/genética , Decitabina , Inhibidores Enzimáticos/farmacología , Epigénesis Genética , Inhibidores de Histona Desacetilasas , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Neoplasias/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Sci Rep ; 9(1): 15827, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31676832

RESUMEN

Spin-polarized supercurrents can be generated with magnetic inhomogeneity at a ferromagnet/spin-singlet-superconductor interface. In such systems, complex magnetic inhomogeneity makes it difficult to functionalise the spin-polarized supercurrents. However, spin-polarized supercurrents in ferromagnet/spin-triplet-superconductor junctions can be controlled by the angle between magnetization and spin of Copper pairs (d-vector), that can effectively be utilized in developing of a field of research known as superconducting spintronics. Recently, we found induction of spin-triplet correlation into a ferromagnet SrRuO3 epitaxially deposited on a spin-triplet superconductor Sr2RuO4, without any electronic spin-flip scattering. Here, we present systematic magnetic field dependence of the proximity effect in Au/SrRuO3/Sr2RuO4 junctions. It is found that induced triplet correlations exhibit strongly anisotropic field response. Such behaviour is attributed to the rotation of the d-vector of Sr2RuO4. This anisotropic behaviour is in contrast with the vortex dynamic. Our results will stimulate study of interaction between ferromagnetism and unconventional superconductivity.

9.
Int J Pharm ; 336(2): 391-5, 2007 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-17234372

RESUMEN

Since liposomes are known as strong adjuvants, we attempted to use liposomes in immunotherapy as adjuvants, and to achieve desensitization in pre-sensitized mice. At first, we sensitized mice with intraperitoneal injection of model antigen, 100 microg ovalbumin (OVA), with Alum and treated them with liposome composed of distearoylphosphatidylcholine (DSPC) and cholesterol (2:1 as a molar ratio), which was coupled with a small amount of OVA (10 microg OVA in 400 nmol DSPC and 200 nmol cholesterol-liposome was injected into 20 g mouse). It is well known that antigen-specific immunotherapy increases IgG blocking antibodies and decreases in IgE antibodies. The treatment with i.v. injection of OVA-liposome at days 8, 10, and 12 after sensitization strongly suppressed OVA-specific IgE production without affecting IgG level after the boost (100 microg OVA with Alum). Moreover, the treatment with high-density OVA-liposome (10 microg OVA in 80 nmol DSPC and 40 nmol cholesterol-liposome/20 g mouse) not only strongly suppressed IgE levels but also reduced IgG production after the boost of OVA-sensitized mice suggesting the importance of liposomal characteristic in desensitization immunotherapy. Next we reduced the dose of OVA-liposome and the desensitization effect was also observed at the dose of as low as 1 microg OVA on OVA-liposome/mouse. On the contrary, free OVA did not affect the production of both IgG and IgE levels. Biodistribution study indicated that OVA-liposome was highly accumulated in spleen of OVA-sensitized mice compared to control liposome at 3 h after i.v. injection. These results suggest that the liposomal OVA effectively interacts with and desensitizes immune cells, therefore, liposomes coupling with a certain antigen may be effective in allergy immunotherapy.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antígenos/inmunología , Desensibilización Inmunológica , Inmunoglobulina E/metabolismo , Ovalbúmina/inmunología , Adyuvantes Inmunológicos/farmacocinética , Compuestos de Alumbre , Animales , Antígenos/administración & dosificación , Antígenos/farmacología , Colesterol , Relación Dosis-Respuesta Inmunológica , Esquema de Medicación , Ensayo de Inmunoadsorción Enzimática , Femenino , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/inmunología , Inmunoglobulina E/efectos de los fármacos , Inmunoglobulina G/efectos de los fármacos , Inmunoglobulina G/metabolismo , Liposomas , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/administración & dosificación , Ovalbúmina/farmacocinética , Ovalbúmina/farmacología , Fosfatidilcolinas , Bazo/metabolismo , Distribución Tisular
10.
J Natl Cancer Inst ; 69(4): 777-85, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6181281

RESUMEN

Cancerous lesions and nonneoplastic mucosa of surgically extirpated specimens from 94 patients with colorectal carcinoma (of the right colon, 31 patients; of the left colon, 29 patients; and of the rectum, 34 patients) and endoscopically polypectomized specimens from 18 patients with rectal adenoma were examined with fluorescein isothiocyanate-conjugated or horse-radish peroxidase-conjugated Ulex europaeus agglutinin-I (UEA-I) specific to a certain terminal alpha-L-fucosyl residue in glycoconjugates. Of the 31 patients with right colon cancers, 22 showed positive UEA-I binding in the neoplastic cell apexes, apical luminal borders, and luminal secretions. The adjacent nonneoplastic mucosa of all 31 patients, however, demonstrated positive UEA-I binding in the goblet cell mucus. UEA-I binding was positive for 23 of the 29 left colon cancers and for 28 of the 34 rectal cancers, although UEA-I binding was not revealed in the adjacent nonneoplastic mucosa for most of the cases. Of the 18 rectal adenomas, 12 specimens showed positive UEA-I binding in the apical secretions of their adenoma cells. Marked regional differences of UEA-I binding in the nonneoplastic mucosae indicated that the constituents of glycoprotein with UEA-I binding sites in goblet cell mucus differed significantly between the human right and left large bowels. Positive UEA-I binding in many rectal cancerous and adenomatous lesions suggested that a neoplastic glycoprotein with alpha-L-fucosyl residue was produced or that the terminal carbohydrate structure of glycoprotein present in the nonneoplastic mucosa was altered to bind easily with UEA-I after the neoplastic transformation had occurred. A possible relation of this UEA-I binding to blood group H(O) substance is discussed.


Asunto(s)
Adenoma/metabolismo , Aglutininas/metabolismo , Carcinoma/metabolismo , Neoplasias del Colon/metabolismo , Glicoproteínas/metabolismo , Mucosa Intestinal/metabolismo , Sitios de Unión , Humanos , Moco/metabolismo , Proteínas de Neoplasias/análisis , Neoplasias del Recto/metabolismo , Coloración y Etiquetado
11.
J Natl Cancer Inst ; 71(1): 19-24, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6345880

RESUMEN

Our previous lectin-binding study of the human colorectal mucosa revealed that, in the distal large bowel, Ulex europaeus agglutinin-L (UEA-l) binding was detectable in adenocarcinomas and adenomas, whereas it usually was not found in the normal epithelium. The aim of the present study was to obtain further information about the chemical nature of the constituents of the epithelium in polyposis coli and solitary colorectal adenoma. UEA-l binding to demonstrate alpha-L-fucosyl residue-containing glycoproteins was conducted on entire colon specimens from 4 patients with polyposis coli and on polypectomy specimens from 23 patients with solitary adenomas of the sigmoid colon and rectum with the use of a highly sensitive lectin-antilectin immunoperoxidase method. In the rectosigmoid area of all 4 patients with polyposis coli, positive UEA-l staining was observed not only in the adenomatous epithelium but also in the nonneoplastic epithelium intervening between the polyps. In contrast, in 18 of 23 patients with solitary adenomas, positive UEA-l staining was observed only in the adenomatous epithelium but not in the adjacent nonneoplastic epithelium. In the remaining 5 solitary adenomas, UEA-l staining was shown neither in the adenomatous epithelium nor in the adjacent nonneoplastic epithelium.


Asunto(s)
Adenoma/metabolismo , Neoplasias Intestinales/metabolismo , Pólipos Intestinales/metabolismo , Lectinas/análisis , Receptores Mitogénicos/análisis , Adulto , Neoplasias del Colon/metabolismo , Femenino , Histocitoquímica , Humanos , Técnicas para Inmunoenzimas , Mucosa Intestinal/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias del Recto/metabolismo , Neoplasias del Colon Sigmoide/metabolismo
12.
J Natl Cancer Inst ; 75(2): 219-26, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3894751

RESUMEN

Glycoproteins binding to Ulex europaeus agglutinin-I (UEA-I) lectin, which recognizes the terminal alpha-L-fucose residue, were analyzed in 18 cases of human colorectal carcinoma by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by the Western blotting method. In the distal large bowel (descending and sigmoid colon and rectum), high-molecular-weight glycoproteins binding to UEA-I existed in carcinoma tissue but not in normal mucosa. In the proximal large bowel (ascending and transverse colon), high-molecular-weight glycoproteins binding to UEA-I were found both in normal mucosa and in carcinoma tissue, whereas those from the carcinoma tissue had an apparently lower molecular weight as compared to the weight of those from the normal mucosa. Thus there is a biochemical difference in UEA-I binding glycoproteins between the normal mucosa and the carcinoma tissue, although in our previous histochemical study no difference was observed in UEA-I binding glycoproteins of the proximal large bowel between the carcinoma tissue and the normal mucosa. Furthermore, carcinoembryonic antigen from the carcinoma tissue was found to have the same electrophoretical mobility as the UEA-I binding glycoproteins.


Asunto(s)
Antígeno Carcinoembrionario/análisis , Neoplasias del Colon/inmunología , Glicoproteínas/inmunología , Lectinas , Proteínas de Neoplasias/inmunología , Lectinas de Plantas , Neoplasias del Recto/inmunología , Anciano , Antígenos de Grupos Sanguíneos/inmunología , Colodión , Electroforesis en Gel de Poliacrilamida , Femenino , Histocitoquímica , Humanos , Técnicas para Inmunoenzimas , Mucosa Intestinal/análisis , Masculino , Persona de Mediana Edad , Receptores Mitogénicos/análisis
13.
Cancer Res ; 56(15): 3468-73, 1996 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8758913

RESUMEN

The activities of GlcNAc:beta1-->3 and GlcNAc:beta1->4 galactosyltransferases in normal human colonic mucosa and well or moderately differentiated colonic adenocarcinomas and their enzyme-kinetic characteristics were investigated. After UDP-[3H]galactose and N-linked type monoantennary oligosaccharides GlcNAc beta1-->2Man alpha1-->3(6)Man beta1-->4GlcNAc) had been incubated with microsome fractions prepared from these tissues, the synthesized [3H]galactose-labeled oligosaccharides were analyzed by Ricinus communis agglutinin-I agarose chromatography, Streptococcus 6646K beta-galactosidase, Gal beta1-->4-specific diplococcal beta-galactosidase, and Gal beta1-->3GlcNAc-specific lacto-N-biosidase digestion. The beta-galactosyltransferases from normal mucosa synthesized both type 1 and type 2 chains at comparable levels, whereas those from adenocarcinomas predominantly synthesized type 2 chains. To our knowledge, this is the first quantitative estimation of GlcNAc:beta1-->3 galactosyltransferase activity toward N-linked sugar chains. Furthermore, we compared the two galactosyltransferase activities in 10 normal mucosa and adenocarcinoma samples and found that while there existed similar levels of GlcNAc:beta1-->4 galactosyltransferase activity in normal mucosa and adenocarcinomas, GlcNAc:beta1-->3 galactosyltransferase activity apparently decreased from 0.67 +/- 0.26 (normal mucosa) to 0.18 +/- 0.11 nmol/min/mg of protein (adenocarcinomas). These results are consistent with those of comparative structural studies on N-linked sugar chains of carcinoembryonic antigen and its normal counterparts and suggest that in the process of differentiated carcinogenesis of human colonic tissues, the expression of GlcNAc:beta1-->3 galactosyltransferase is negatively regulated.


Asunto(s)
Acetilglucosamina/metabolismo , Adenocarcinoma/enzimología , Colon/enzimología , Neoplasias del Colon/enzimología , Galactosiltransferasas/metabolismo , Mucosa Intestinal/enzimología , Oligosacáridos/metabolismo , Anciano , Anciano de 80 o más Años , Secuencia de Carbohidratos , Femenino , Humanos , Cinética , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular
14.
Cancer Res ; 55(18): 4196-200, 1995 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-7664297

RESUMEN

Thrombomodulin (TM) is thrombin receptor that was identified originally on the endothelium and acts as a natural anticoagulant. However, we reported previously that TM was also expressed in the squamous epithelium mainly at the intercellular bridges. In this study, we examined TM expression in the primary lesions of 106 patients with esophageal squamous cell carcinomas and in the lymph node metastatic lesions of 59 patients using immunohistochemical methods. The carcinoma tissues expressed TM mainly at the cell-cell boundaries and in the cytoplasm. When TM expression was compared between the primary and metastatic lesions in the 59 patients who had lymph node metastasis, 41 (69%) showed decreased TM expression, 18 (31%) showed no change, and none (0%) showed an increase in the metastatic lesions. Wilcoxon's signed-rank test indicated that tumor cells that were positive for TM expression were significantly rarer in the metastatic lesions than in the primary tumors (P < 0.0001). This result indicates that the decrease in TM expression is associated with metastasis of the carcinoma cells. This phenomenon is very similar to that of E-cadherin, although the structures of both molecules are quite different. The reduction of TM expression seems to play an important role in the metastatic process of esophageal cancer.


Asunto(s)
Carcinoma de Células Escamosas/química , Neoplasias Esofágicas/química , Trombomodulina/análisis , Adulto , Anciano , Anciano de 80 o más Años , Animales , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Esófago/química , Femenino , Humanos , Ganglios Linfáticos/química , Metástasis Linfática , Masculino , Persona de Mediana Edad , Conejos
15.
Nat Commun ; 7: 13220, 2016 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-27782151

RESUMEN

Efforts have been ongoing to establish superconducting spintronics utilizing ferromagnet/superconductor heterostructures. Previously reported devices are based on spin-singlet superconductors (SSCs), where the spin degree of freedom is lost. Spin-polarized supercurrent induction in ferromagnetic metals (FMs) is achieved even with SSCs, but only with the aid of interfacial complex magnetic structures, which severely affect information imprinted to the electron spin. Use of spin-triplet superconductors (TSCs) with spin-polarizable Cooper pairs potentially overcomes this difficulty and further leads to novel functionalities. Here, we report spin-triplet superconductivity induction into a FM SrRuO3 from a leading TSC candidate Sr2RuO4, by fabricating microscopic devices using an epitaxial SrRuO3/Sr2RuO4 hybrid. The differential conductance, exhibiting Andreev-reflection features with multiple energy scales up to around half tesla, indicates the penetration of superconductivity over a considerable distance of 15 nm across the SrRuO3 layer without help of interfacial complex magnetism. This demonstrates potential utility of FM/TSC devices for superspintronics.

16.
Nat Commun ; 7: 10903, 2016 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-27020134

RESUMEN

The magnetic field-induced changes in the conductivity of metals are the subject of intense interest, both for revealing new phenomena and as a valuable tool for determining their Fermi surface. Here we report a hitherto unobserved magnetoresistive effect in ultra-clean layered metals, namely a negative longitudinal magnetoresistance that is capable of overcoming their very pronounced orbital one. This effect is correlated with the interlayer coupling disappearing for fields applied along the so-called Yamaji angles where the interlayer coupling vanishes. Therefore, it is intrinsically associated with the Fermi points in the field-induced quasi-one-dimensional electronic dispersion, implying that it results from the axial anomaly among these Fermi points. In its original formulation, the anomaly is predicted to violate separate number conservation laws for left- and right-handed chiral (for example, Weyl) fermions. Its observation in PdCoO2, PtCoO2 and Sr2RuO4 suggests that the anomaly affects the transport of clean conductors, in particular near the quantum limit.

17.
Biochim Biophys Acta ; 1073(1): 155-60, 1991 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-1991130

RESUMEN

The distribution of cathepsins D and E in leukocytes and erythrocyte ghosts of several mammalian species, and in HL-60 and K-562 cells was examined by means of a combined application of electrophoretic and immunochemical methods. Cathepsin D was found in leukocytes of all species examined, but the distribution of cathepsin E was found to be species-specific: pigs, cows and goats had no cathepsin E activity in leukocytes or erythrocytes at all. In humans, cathepsin E occurred in erythrocytes but not in leukocytes, which contrasted with the guinea pig pattern of its presence in leukocytes and its absence in erythrocytes. No cathepsin E-related enzymes were found in HL-60 or K-562 cells, but these human leukemic cells contained cathepsin D-related enzyme forms that are electrophoretically distinct from normal leukocyte cathepsin D. The present results are inconsistent with the view that cathepsin E may be involved as an essential factor in the biological functions of leukocytes or erythrocytes.


Asunto(s)
Células Sanguíneas/enzimología , Catepsinas/sangre , Animales , Catepsina D/sangre , Catepsina E , Línea Celular , Membrana Eritrocítica/enzimología , Humanos , Leucocitos Mononucleares/enzimología , Neutrófilos/enzimología , Especificidad de la Especie
18.
J Clin Pathol ; 58(8): 845-52, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16049287

RESUMEN

BACKGROUND: Many patients with invasive ductal carcinoma of the pancreas (IDC) have a poor outcome. MUC4 expression has been implicated as a marker for diagnosis and progression of IDC, but there are no studies of the relation between MUC4 expression and patient prognosis in IDC. AIMS: To investigate the prognostic significance of MUC4 expression in IDC. METHODS: The expression profiles of MUC4, ErbB2, p27, and MUC1 were investigated in IDC tissues from 135 patients by means of immunohistochemistry. RESULTS: MUC4 was expressed in 43 of the 135 patients with IDC (31.9%). The survival of 21 patients with high MUC4 expression (>20% of neoplastic cells stained) was significantly worse than that of the 114 patients with low MUC4 expression (<20% of neoplastic cells stained) (p = 0.0043). Univariate analysis showed that high MUC4 expression (p = 0.0061), large primary tumour status (>T2) (p = 0.0436), distant metastasis (p = 0.0383), lymphatic invasion (p = 0.0243), and surgical margins (p = 0.0333) were significant risk factors affecting the outcome of patients with IDC. Backward stepwise multivariate analysis showed that MUC4 expression (p = 0.0121), lymph node metastasis (p = 0.0245), and lymphatic invasion (p = 0.0239) were significant independent risk factors. ErbB2, p27, and MUC1 were not independent risk factors. CONCLUSIONS: This study shows that MUC4 expression in IDC is a new independent factor for poor prognosis and predicts the outcome of patients with IDC.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Mucinas/metabolismo , Neoplasias Pancreáticas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/secundario , Progresión de la Enfermedad , Femenino , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , Persona de Mediana Edad , Mucina 4 , Invasividad Neoplásica , Proteínas de Neoplasias/metabolismo , Páncreas/metabolismo , Neoplasias Pancreáticas/patología , Pronóstico , Factores de Riesgo , Análisis de Supervivencia
19.
Clin Cancer Res ; 4(11): 2605-14, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9829723

RESUMEN

Our previous immunohistochemical studies for the expression of MUC1 mucin antigen (which was detected by monoclonal antibody DF3) and MUC2 mucin antigen (which was detected by polyclonal antibody anti-MRP) in pancreatic and intrahepatic bile duct tumors demonstrated that invasive carcinoma with poor outcome showed a pattern of MUC1+ and MUC2- expression, whereas many of the noninvasive tumors with favorable outcome showed a pattern of MUC1- and MUC2+ expression. To clarify the relationship between the expression of these mucin antigens and the biological properties of gastric cancers, the expression of MUC1 and MUC2 mucin antigens was examined immunohistochemically in 136 patients with gastric cancer invading the submucosa or the deeper layer, and the survival of the antigen-positive and antigen-negative patient groups was compared using the Kaplan-Meier method. For MUC1 mucin expression, different glycoforms of MUC1 were examined using four monoclonal antibodies (NCL-MUC-1-CORE, DF3, MY.1E12, and HMFG-1). The patients with MUC1+ mucin antigen staining in the carcinoma showed significantly worse survival than those with MUC1- mucin antigen staining. In contrast, the patients with MUC2+ mucin antigen staining in the carcinoma showed significantly better survival than those with MUC2- mucin antigen staining. In conclusion, MUC1 antigen expression was associated with a poor outcome in patients with gastric cancer, irrespective of its glycosylation status, and MUC1 is thus considered to be a useful prognostic factor for poor outcome in patients. In contrast, MUC2 antigen expression is a prognostic factor associated with a favorable outcome in patients. In addition, combined evaluation of the MUC1 and MUC2 mucin staining is clinically useful to predict outcome in patients with gastric cancer.


Asunto(s)
Mucina-1/biosíntesis , Mucinas/biosíntesis , Neoplasias Gástricas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/biosíntesis , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Glicosilación , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Mucina 2 , Pronóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/fisiopatología , Tasa de Supervivencia
20.
Gene ; 214(1-2): 77-86, 1998 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-9651486

RESUMEN

Filensin (also called CP94; CP95; CP97; 115kDa protein) is a component of the lens-specific beaded filament which is believed to be functionally important in lens fiber cell differentiation and in maintaining lens fiber cell conformation and transparency. A 17.2kb fragment containing the 5'-upstream sequence of the filensin gene was isolated. S1-mapping analysis determined the transcription start point (tsp; +1) which locates at 94base pairs upstream from the initiating ATG on the filensin gene. In addition to a major tsp, a minor tsp (-136) was observed. DNA sequence of the fragment around the tsp (-2144 to +155) was identified. Analysis of the DNA sequence of the promoter region around tsp revealed two motifs with sequence homology to Sox2 and Maf recognition sequences in addition to one GATA-1 site, two Sp1 binding sites, and three AP-2 binding motifs. No TATA-box or CCAAT-motif was found around the tsp region. A series of sequentially deleted fragments of (-2144 to +40) were fused to firefly luciferase reporter plasmid pGL2 and tested for activity in chicken embryonic lens explants. A minimal promoter region for mouse filensin of (-70 to +40) was identified. The lens-specific promoter activity was detected using lens explants cultured within 12h after dissection. The activity was remarkably enhanced by culture in the presence of 5ng/ml of basic fibroblast growth factor. Each one of the Sp1 and AP-2 binding motifs was localized to the fragment of (-27 to +40) using electrophoretic mobility shift assays. These are the first data to identify the basic elements to the 5'-upstream sequences of the filensin gene, namely the tsp and the minimal filensin promoter.


Asunto(s)
Proteínas del Ojo/genética , Proteínas de Filamentos Intermediarios/genética , Regiones Promotoras Genéticas , Animales , Secuencia de Bases , Sitios de Unión/genética , Embrión de Pollo , ADN/genética , ADN/metabolismo , Cartilla de ADN/genética , Proteínas de Unión al ADN/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Genes Reporteros , Cristalino/citología , Cristalino/metabolismo , Luciferasas/genética , Ratones , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/efectos de los fármacos , Mapeo Restrictivo , Eliminación de Secuencia , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción AP-2 , Factores de Transcripción/metabolismo
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