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1.
Eur J Clin Microbiol Infect Dis ; 34(11): 2191-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26282790

RESUMEN

Surveillance of Streptococcus pneumoniae serotypes is important for the successful implementation of vaccination strategies to prevent the spread of invasive pneumococcal diseases. The standard method of serotyping of pneumococcal isolates is the phenotypic Neufeld test, which is cost- and labor-intensive. Recently, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been implemented as a rapid, simple and inexpensive method for identifying species. We evaluated the performance of MALDI-TOF MS for serotyping ten major serotypes of S. pneumoniae in Japan (serotypes 3, 6B, 15A, 15C, 19A, 19 F, 23A, 24 F, 35B and 38) using the Biotyper and ClinProTools. After optimizing the settings, we validated their serotyping performance for serotypes 3, 15A and 19A using a separate set of isolates that were not used in the creation of the classification algorithms. A total of 574 isolates of S. pneumoniae collected from Japanese nationwide surveillance studies were included. Of these, 407 isolates belonged to the ten major serotypes. Biotyper and ClinProTools correctly identified 77.9 % and 84.0 %, respectively, of the ten major serotype isolates. The validation analysis included a total of 113 isolates of the serotypes 3, 15A and 19A isolates. Biotyper and ClinProTools correctly identified 85.0 % and 69.9 % of the validation cohort isolates, respectively. MALDI-TOF MS has the potential to discriminate the ten major S. pneumoniae serotypes prevalent in Japan.


Asunto(s)
Serotipificación/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Streptococcus pneumoniae/química , Streptococcus pneumoniae/clasificación , Adolescente , Niño , Preescolar , Monitoreo Epidemiológico , Humanos , Lactante , Recién Nacido , Japón , Infecciones Neumocócicas/microbiología
2.
Phys Rev Lett ; 110(24): 247601, 2013 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-25165961

RESUMEN

The interface between LaAlO(3) and SrTiO(3) hosts a two-dimensional electron system of itinerant carriers, although both oxides are band insulators. Interface ferromagnetism coexisting with superconductivity has been found and attributed to local moments. Experimentally, it has been established that Ti 3d electrons are confined to the interface. Using soft x-ray angle-resolved resonant photoelectron spectroscopy we have directly mapped the interface states in k space. Our data demonstrate a charge dichotomy. A mobile fraction contributes to Fermi surface sheets, whereas a localized portion at higher binding energies is tentatively attributed to electrons trapped by O vacancies in the SrTiO(3). While photovoltage effects in the polar LaAlO(3) layers cannot be excluded, the apparent absence of surface-related Fermi surface sheets could also be fully reconciled in a recently proposed electronic reconstruction picture where the built-in potential in the LaAlO(3) is compensated by surface O vacancies serving also as a charge reservoir.

3.
J Med Case Rep ; 17(1): 186, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37101309

RESUMEN

BACKGROUND: Chromosome 5p partial monosomy (5p-syndrome) and chromosome 6p partial trisomy are chromosomal abnormalities that result in a variety of symptoms, but liver dysfunction is not normally one of them. Alagille syndrome (OMIM #118450) is a multisystem disorder that is defined clinically by hepatic bile duct paucity and cholestasis, in association with cardiac, skeletal, and ophthalmologic manifestations, and characteristic facial features. Alagille syndrome is caused by mutations in JAG1 on chromosome 20 or NOTCH2 on chromosome 1. Here, we report a preterm infant with karyotype 46,XX,der(5)t(5,6)(p15.2;p22.3) and hepatic dysfunction, who was diagnosed as having incomplete Alagille syndrome. CASE PRESENTATION: The Japanese infant was diagnosed based on the cardiac abnormalities, ocular abnormalities, characteristic facial features, and liver pathological findings. Analysis of the JAG1 and NOTCH sequences failed to detect any mutations in these genes. CONCLUSIONS: These results suggest that, besides the genes that are known to be responsible for Alagille syndrome, other genetic mutations also may cause Alagille syndrome.


Asunto(s)
Síndrome de Alagille , Lactante , Humanos , Recién Nacido , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Síndrome de Alagille/patología , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Recien Nacido Prematuro , Cariotipo
4.
Sci Rep ; 11(1): 18654, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34545160

RESUMEN

Band-gap engineering is one of the fundamental techniques in semiconductor technology and also applicable in next generation spintronics using the spin degree of freedom. To fully utilize the spintronic materials, it is essential to optimize the spin-dependent electronic structures in the operando conditions by applying magnetic and/or electric fields. Here we present an advanced spectroscopic technique to probe the spin-polarized electronic structures by using magnetic circular dichroism (MCD) in resonant inelastic soft X-ray scattering (RIXS) under an external magnetic field. Thanks to the spin-selective dipole-allowed transitions in RIXS-MCD, we have successfully demonstrated the direct evidence of the perfectly spin-polarized electronic structures for the prototypical halfmetallic Heusller alloy [Formula: see text]. RIXS-MCD is a promising tool to probe the spin-dependent carriers and band-gap induced in the buried magnetic layers in an element specific way under the operando conditions.

5.
Nature ; 403(6768): 396-8, 2000 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-10667784

RESUMEN

Electron correlations are known to play an important role in determining the unusual physical properties of a variety of compounds. Such properties include high-temperature superconductivity, heavy fermion behaviour and metal-to-insulator transitions. High-resolution photoelectron spectroscopy (PES) provides a means of directly probing the electronic states (particularly those near the Fermi level) in these materials, but the short photoelectron mean free paths (< or = 5 A) associated with the low excitation energies conventionally used (< or = 120 eV) make this a surface-sensitive technique. Now that high-resolution PES is possible at much higher energies, with mean free paths as long as 15 A (ref. 6), it should become feasible to probe the bulk electronic states in these materials. Here we demonstrate the power of this technique by applying it to the cerium compounds CeRu2Si2 and CeRu2. Previous PES studies of these compounds revealed very similar spectra for the Ce 4f electronic states, yet it is expected that such states should be different owing to their differing degrees of hybridization with other valence bands. Our determination of the bulk Ce 4f electronic states of these compounds resolves these differences.

6.
J Hosp Infect ; 104(2): 200-206, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31568809

RESUMEN

BACKGROUND: Infection control strategies are implemented in all neonatal intensive care units (NICUs); however, the details of the strategies seem to differ among institutions. The purpose of this survey was to investigate the current implementation status of infection control strategies in NICUs in Japan and to identify and recommend appropriate strategies for the prevention of outbreaks in neonatal units. METHODS: This survey documented the current implementation status and methods of selected infection prevention and control measures (active surveillance cultures and standard precaution) in 453 Japanese NICUs/neonatal units registered with the Japan Society of Perinatal and Neonatal Medicine, using questionnaires, in May 2018. FINDINGS: The response rate was 48.1% (level I institutions, 25.5%; level II, 55.9%; level III, 64.2%). Surveillance cultures were performed every week and targeted all bacteria in most units. The proportion of level III institutions that experienced outbreaks over the previous five years was significantly higher than that of level II institutions (55% vs 27%, P=0.0003). However, wearing a mask was less frequently recommended in level III institutions (55.7%) than in level II institutions (67.9%). Meticillin-resistant Staphylococcus aureus (MRSA) was the most frequently reported bacterial pathogen responsible for NICU outbreaks. CONCLUSION: Infection prevention and control practices regarding active pathogen surveillance cultures and the use of barrier precautions varied widely in Japanese neonatal units. National guidelines and evidence-based recommendations are needed to rationalize and standardize current infection prevention and control practices in neonatal units in Japan.


Asunto(s)
Infección Hospitalaria/prevención & control , Control de Infecciones/métodos , Control de Infecciones/estadística & datos numéricos , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Encuestas de Atención de la Salud , Humanos , Japón/epidemiología , Estudios Retrospectivos
7.
J Neonatal Perinatal Med ; 13(1): 135-138, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32280067

RESUMEN

Placental chorioangioma (CA) is a benign placental tumor. No specific treatment is required for asymptomatic cases. We report a female infant born to a mother with giant placental CA. However fetal growth was normal and, fetal hydrops was not detected by ultrasound examination until delivery, she had hydrops, subgaleal hematoma, thrombocytopenia, hemolytic anemia, respiratory distress and circulatory failure after birth. She was successfully treated without any neurological sequelae. At 2 months of age, infantile hemangioma appeared in her lower lip. The present case suggested that giant placental CA might cause postnatal problems and be associated with the development of infantile hemangioma.


Asunto(s)
Anemia Hemolítica/etiología , Edema/etiología , Hemangioma/complicaciones , Neoplasias de los Labios/patología , Enfermedades Placentarias/patología , Complicaciones Neoplásicas del Embarazo/patología , Síndrome de Dificultad Respiratoria del Recién Nacido/etiología , Choque/etiología , Antagonistas Adrenérgicos beta/uso terapéutico , Anemia Hemolítica/terapia , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/terapia , Edema/terapia , Transfusión de Eritrocitos , Femenino , Hemangioma/diagnóstico por imagen , Hemangioma/tratamiento farmacológico , Hemangioma/patología , Hepatomegalia/etiología , Humanos , Hipoalbuminemia/etiología , Hipoalbuminemia/terapia , Recién Nacido , Neoplasias de los Labios/tratamiento farmacológico , Enfermedades Placentarias/diagnóstico por imagen , Plasma , Embarazo , Complicaciones Neoplásicas del Embarazo/diagnóstico por imagen , Propranolol/uso terapéutico , Púrpura/etiología , Púrpura/terapia , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Choque/terapia , Esplenomegalia/etiología , Trombocitopenia/etiología , Trombocitopenia/terapia , Carga Tumoral , Ultrasonografía Prenatal , Vasoconstrictores/uso terapéutico
8.
J Indian Soc Pedod Prev Dent ; 27(2): 125-30, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19736508

RESUMEN

Traumatic lesions in primary teeth are frequent in pediatric patients and can cause problems both to the deciduous tooth and permanent successor. The impact strength on deciduous tooth can reach the growing permanent tooth, affecting its morphology, structure and position, or even hampering its proper development. This report describes an aesthetic-functional rehabilitation process in an 8 year 10 month old boy during a multidisciplinary treatment held at the Clinical Center of Dental Trauma in Primary Teeth of the Pediatric Dentistry of Dental College of University of São Paulo, Brazil. The patient presented bilateral posterior cross bite and the permanent left upper central incisor with ectopic eruption and enamel hypoplasy, preceded by avulsion of element 61, occurred when the patient was 1.6 years old. After diagnosis and treatment planning, a quick expansion of jaws was recommended with Hass-type rapid expander and orthodontic leveling with fixed braces. Due to the ectopic eruption, the gingival contour had been altered and hypertrophia was found, compromising aesthetics and avoiding local hygienic procedures. Gingivoplasty was carried out with high-intensity Diode Laser, followed by aesthetic restoration with compound resin. It was concluded that after deciduous teeth traumatism it is important that the patient undergoes clinic and radiographic assistance until the permanent teeth erupt so that an adequate multidisciplinary treatment can be offered to the patient.


Asunto(s)
Avulsión de Diente/complicaciones , Diente Primario/lesiones , Niño , Hipoplasia del Esmalte Dental/etiología , Hipoplasia del Esmalte Dental/terapia , Restauración Dental Permanente , Hipertrofia Gingival/etiología , Hipertrofia Gingival/cirugía , Gingivoplastia , Humanos , Masculino , Maloclusión/etiología , Maloclusión/terapia , Técnica de Expansión Palatina , Grupo de Atención al Paciente , Erupción Ectópica de Dientes/etiología , Erupción Ectópica de Dientes/terapia
9.
Nat Commun ; 10(1): 505, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30705281

RESUMEN

Many properties of real materials can be modeled using ab initio methods within a single-particle picture. However, for an accurate theoretical treatment of excited states, it is necessary to describe electron-electron correlations including interactions with bosons: phonons, plasmons, or magnons. In this work, by comparing spin- and momentum-resolved photoemission spectroscopy measurements to many-body calculations carried out with a newly developed first-principles method, we show that a kink in the electronic band dispersion of a ferromagnetic material can occur at much deeper binding energies than expected (Eb = 1.5 eV). We demonstrate that the observed spectral signature reflects the formation of a many-body state that includes a photohole bound to a coherent superposition of renormalized spin-flip excitations. The existence of such a many-body state sheds new light on the physics of the electron-magnon interaction which is essential in fields such as spintronics and Fe-based superconductivity.

10.
J Clin Invest ; 90(3): 1145-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1522222

RESUMEN

C-type natriuretic peptide (CNP), the third member of the natriuretic peptide family, is thus far known to be distributed mainly in the central nervous system and is considered to act as a neuropeptide, in contrast to atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), which act as cardiac hormones. Recently, we and others have demonstrated that the ANP-B receptor, which is selectively activated by CNP, is localized not only in the central nervous system but in peripheral tissues, including blood vessels. This finding has made us speculate regarding the peripheral production of CNP. In the present study, cultured endothelial cells were examined for CNP production by RIA and Northern blot analysis. CNP-like immunoreactivity was detected in the conditioned media of endothelial cells. Northern blot analysis detected CNPmRNA with a size of 1.2 kb. In addition, transforming growth factor (TGF)-beta, one of the key growth factors for vascular remodeling, markedly stimulated the expression of CNPmRNA and induced a tremendous increase in CNP secretion. We could also detect CNP transcript in the bovine thoracic aorta using the reverse transcription-polymerase chain reaction method. The present study demonstrates the endothelial production of CNP and suggests that a member of the natriuretic peptide family may act as a local regulator in vascular walls. Since evidence for the pathophysiological importance of the vascular renin-angiotensin system has been accumulating and the natriuretic peptide system is known to be antagonistic to the renin-angiotensin system, the possible existence of "vascular natriuretic peptide system" may prove to be of physiological and clinical relevance.


Asunto(s)
Endotelio Vascular/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Factor de Crecimiento Transformador beta/farmacología , Animales , Secuencia de Bases , Bovinos , Células Cultivadas , Expresión Génica/efectos de los fármacos , Datos de Secuencia Molecular , Péptido Natriurético Tipo-C , Proteínas del Tejido Nervioso/genética , ARN Mensajero/análisis , Sistema Renina-Angiotensina/fisiología
11.
J Clin Invest ; 96(3): 1280-7, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7657802

RESUMEN

We previously demonstrated that brain natriuretic peptide (BNP) is a cardiac hormone mainly produced in the ventricle, while the major production site of atrial natriuretic peptide (ANP) is the atrium. To assess the pathophysiological role of BNP in ventricular overload, we have examined the gene expression of BNP, In comparison with that of ANP, in a model of cardiac hypertrophy using cultured neonatal rat ventricular cardiocytes. During cardiocyte hypertrophy evoked by endothelin-1, Phenylephrine, or PMA, the steady state level of BNP mRNA increased as rapidly as the "immediate-early" induction of the c-fos gene expression, and reached a maximal level within 1 h. Actinomycin D, a transcriptional inhibitor, completely diminished the response, while the translational blocked with cycloheximide did not inhibit it. In contrast, ANP mRNA began to increase 3 h after the stimulation, and accumulated during cardiocyte hypertrophy. The BNP secretion from ventricular cardiocytes was also stimulated, more rapidly than the ANP secretion. Furthermore, the turnover of BNP mRNA was significantly faster than that of ANP mRNA, being consistent with the existence of AUUUA motif in the 3'-untranslated region of BNP mRNA. These results demonstrate that the gene expression of BNP is distinctly regulated from that of ANP at transcriptional and posttranscriptional levels, and indicate that the characteristics of the BNP gene expression are suitable for its possible role as an " emergency" cardiac hormone against ventricular overload.


Asunto(s)
Factor Natriurético Atrial/biosíntesis , Cardiomegalia/metabolismo , Regulación de la Expresión Génica , Miocardio/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , ARN Mensajero/metabolismo , Transcripción Genética , Animales , Animales Recién Nacidos , Secuencia de Bases , Células Cultivadas , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Cartilla de ADN , Endotelinas/farmacología , Activación Enzimática/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Ventrículos Cardíacos , Cinética , Datos de Secuencia Molecular , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/aislamiento & purificación , Fenilefrina/farmacología , Proteína Quinasa C/metabolismo , ARN Mensajero/biosíntesis , Radioinmunoensayo , Ratas , Ratas Wistar , Mapeo Restrictivo , Acetato de Tetradecanoilforbol/farmacología
12.
J Clin Invest ; 87(4): 1402-12, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1849149

RESUMEN

Using a specific radioimmunoassay for human brain natriuretic peptide (hBNP) with a monoclonal antibody, we have investigated its synthesis, secretion, and clearance in comparison with those of atrial natriuretic peptide (ANP) in normal subjects and patients with congestive heart failure (CHF). Mean BNP-like immunoreactivity (-LI) levels in normal atrium and ventricle were 250 and 18 pmol/g, respectively. The plasma BNP-LI level in normal subjects was 0.90 +/- 0.07 fmol/ml, which was 16% of the ANP-LI level. In contrast, the plasma BNP-LI level markedly increased in patients with CHF in proportion to its severity, and surpassed the ANP-LI level in severe cases. There was a significant step-up of the plasma BNP-LI level in the coronary sinus (CS) compared with that in the aortic root (Ao) and the difference between these BNP-LI levels, delta(CS-Ao)BNP, also increased with the severity of CHF. In addition, the step-up of the BNP-LI level in the anterior interventricular vein [delta(AIV-Ao)BNP] was comparable to delta(CS-Ao)BNP, indicating that BNP is secreted mainly from the ventricle. Predominant BNP synthesis in the ventricle was also confirmed by Northern blot analysis. Catheterization and pharmacokinetic studies revealed that hBNP is cleared from the circulation more slowly than alpha-hANP; this was in part attributed to lower (about 7%) binding affinity of hBNP to clearance receptors than that of alpha-hANP. A predominant molecular form of BNP-LI in the heart and plasma was a 3-kD form corresponding to hBNP. These results indicate that BNP is a novel cardiac hormone secreted predominantly from the ventricle, and that the synthesis, secretion and clearance of BNP differ from those of ANP, suggesting discrete physiological and pathophysiological roles of BNP in a dual natriuretic peptide system.


Asunto(s)
Factor Natriurético Atrial/fisiología , Proteínas del Tejido Nervioso/fisiología , Anticuerpos Monoclonales/inmunología , Northern Blotting , Cateterismo Cardíaco , Insuficiencia Cardíaca/metabolismo , Humanos , Miocardio/metabolismo , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/farmacocinética , Radioinmunoensayo , Receptores del Factor Natriurético Atrial , Receptores de Superficie Celular/metabolismo
13.
J Clin Invest ; 93(5): 1911-21, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8182124

RESUMEN

Brain natriuretic peptide (BNP) is a cardiac hormone that occurs predominantly in the ventricle. To study the roles of BNP in chronic cardiovascular regulation, we isolated mouse BNP cDNA and genomic clones, and generated transgenic mice with elevated plasma BNP concentration. The mouse BNP gene was organized into three exons and two introns. Two BNP mRNA species were identified, which were generated by the alternative mRNA splicing. The ventricle was a major site of BNP production in mice. Mouse preproBNP was a 121- (or 120-) residue peptide, and its COOH-terminal 45-residue peptide was the major storage form in the heart. Transgenic mice carrying the human serum amyloid P component/mouse BNP fusion gene were generated so that the hormone expression is targeted to the liver. In the liver of these mice, considerable levels of BNP mRNA and peptide were detected, reaching up to 10-fold greater than in the ventricle. These animals showed 10- to 100-fold increase in plasma BNP concentration accompanied by elevated plasma cyclic GMP concentration, and had significantly lower blood pressure than their nontransgenic littermates. The present study demonstrates that these mice provide a useful model system with which to assess the roles of BNP in cardiovascular regulation and suggests the potential usefulness of BNP as a long-term therapeutic agent.


Asunto(s)
Química Encefálica , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Empalme Alternativo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Reacciones Cruzadas , GMP Cíclico/sangre , ADN Complementario/genética , Expresión Génica , Ventrículos Cardíacos/metabolismo , Hígado/química , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Datos de Secuencia Molecular , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/sangre , Radioinmunoensayo , Proteínas Recombinantes de Fusión/biosíntesis , Homología de Secuencia de Aminoácido , Distribución Tisular
14.
J Clin Invest ; 94(3): 1059-68, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8083346

RESUMEN

Brain and atrial natriuretic peptides (BNP and ANP) are cardiac hormones with diuretic, natriuretic, and vasodilatory activities. Cardiomyopathic hamsters are widely used animal models of heart failure. Due to the structural divergence of BNP among species, examination on pathophysiological roles of BNP using cardiomyopathic hamsters is so far impossible. We therefore isolated hamster BNP and ANP cDNAs, and investigated synthesis and secretion of these peptides in normal and cardiomyopathic hamsters. The COOH-terminal 32-residue peptide of cloned hamster preproBNP with 122 amino acids, preceded by a single arginine residue, supposedly represents hamster BNP showing < 50% homology to rat BNP. Alpha-hamster ANP, 28-residue peptide, is identical to alpha-rat ANP. In hamsters, BNP and ANP occur mainly in the ventricle and the atrium, respectively. The 32-wk-old hypertrophic cardiomyopathic BIO14.6 strain exhibited ventricular hypertrophy. The 32-wk-old dilated cardiomyopathic BIO53.58 strain remained at the stage without apparent heart failure. In BIO14.6 and BIO53.58 strains at this age, ventricular BNP and ANP gene expressions are augmented, and the plasma BNP concentration is elevated to 136 and 108 fmol/ml, respectively, three times greater than the elevated plasma ANP concentration, which well mimics changes of the plasma BNP and ANP concentrations in human heart failure. Cardiomyopathic hamsters, therefore, are useful models to investigate the implication of BNP in human cardiovascular diseases.


Asunto(s)
Factor Natriurético Atrial/biosíntesis , Cardiomiopatías/metabolismo , Expresión Génica , Miocardio/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Secuencia de Aminoácidos , Animales , Factor Natriurético Atrial/genética , Secuencia de Bases , Northern Blotting , Clonación Molecular , Secuencia Conservada , Cricetinae , Cartilla de ADN , Sondas de ADN , ADN Complementario/análisis , ADN Complementario/metabolismo , Atrios Cardíacos , Ventrículos Cardíacos , Humanos , Mesocricetus , Ratones , Datos de Secuencia Molecular , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/genética , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Ratas , Mapeo Restrictivo , Homología de Secuencia de Aminoácido
15.
J Perinatol ; 37(12): 1272-1277, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29022925

RESUMEN

OBJECTIVE: We evaluated cytomegalovirus (CMV) immunoglobulin M (IgM) titer in pregnant women with primary infection as a predictive factor for congenital infection. STUDY DESIGN: Maternal CMV antibody screening during the first trimester was conducted prospectively at 16 centers in Japan between September 2013 and 2015. Women with confirmed maternal primary infection underwent testing for fetal congenital infection, and we investigated the positive predictive value of CMV IgM titer levels for congenital infection in women with a low IgG avidity. RESULTS: We identified 6 (8.6%) cases of congenital infection among 70 pregnant women with positive/borderline IgG, positive IgM and IgG avidity index ⩽35.0% and 11 (39.3%) among 28 women with IgG and/or IgM seroconversion. IgM titer level ⩾6.00 index showed the highest positive predictive value (17.1%). CONCLUSION: High titer of CMV IgM during the first trimester in pregnant women with primary infection is a risk factor for congenital infection.


Asunto(s)
Anticuerpos Antivirales/orina , Infecciones por Citomegalovirus/sangre , Citomegalovirus/inmunología , Inmunoglobulina M/sangre , Complicaciones Infecciosas del Embarazo/sangre , Primer Trimestre del Embarazo/sangre , Adolescente , Adulto , Estudios de Casos y Controles , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Recién Nacido , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Primer Trimestre del Embarazo/inmunología , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto Joven
16.
J Phys Condens Matter ; 29(5): 055002, 2017 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-27911879

RESUMEN

An interface electron state at the junction between a three-dimensional topological insulator film, Bi2Se3, and a ferrimagnetic insulator film, Y3Fe5O12 (YIG), was investigated by measurements of angle-resolved photoelectron spectroscopy and x-ray absorption magnetic circular dichroism. The surface state of the Bi2Se3 film was directly observed and localized 3d spin states of the Fe3+ in the YIG film were confirmed. The proximity effect is likely described in terms of the exchange interaction between the localized Fe 3d electrons in the YIG film and delocalized electrons of the surface and bulk states in the Bi2Se3 film.

17.
Diabetes ; 46(11): 1755-60, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9356022

RESUMEN

The whole-cell patch-clamp method was used to examine the effect of glucagon-like peptide I (GLP-I)(7-36) amide on the activation process of L-type Ca2+ channels of rat pancreatic beta-cells. After depolarization, GLP-I (1-100 nmol/l) caused action potentials in cells exposed to a glucose-free solution for 10 min. The percentage of cells producing action potential depended on the concentration of GLP-I. In some cells, GLP-I caused action potentials without the prior depolarization of the membrane. In cells exposed to the glucose-free solution for longer than 30 min, or in cells that were deprived of ATP by a means of the conventional whole-cell configuration, GLP-I (20 nmol/l) did not cause the electrical excitation. Application of GLP-I augmented the maximum Ba2+ current (IBa) through L-type Ca2+ channels and shifted the current voltage curve to the left. Values of changes in the maximum IBa depended on GLP-I concentration. Application of dibutyryl cAMP (dbcAMP, 1 mmol/l) also augmented IBa. In cells pretreated with Rp-cAMP, dbcAMP did not change the magnitude of IBa. Also in cells pretreated with Rp-cAMP, GLP-I failed to augment IBa. These results suggest that in pancreatic beta-cells, GLP-I, by a cAMP-dependent mechanism, increases opening of L-type Ca2+ channels. cAMP-dependent augmentation of Ca2+ entry as well as cAMP production itself by GLP-I plays a crucial role in controlling insulin secretion.


Asunto(s)
Bario/metabolismo , Canales de Calcio/fisiología , AMP Cíclico/metabolismo , Islotes Pancreáticos/fisiología , Fragmentos de Péptidos/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Adenosina Trifosfato/farmacología , Animales , Bucladesina/farmacología , Canales de Calcio/efectos de los fármacos , Canales de Calcio Tipo L , Células Cultivadas , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacología , Estimulación Eléctrica , Glucagón , Péptido 1 Similar al Glucagón , Péptidos Similares al Glucagón , Glucosa/farmacología , Islotes Pancreáticos/efectos de los fármacos , Cinética , Potenciales de la Membrana/efectos de los fármacos , Ratas , Tionucleótidos/farmacología , Tolbutamida/farmacología
18.
Diabetes ; 48(9): 1741-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10480603

RESUMEN

The effects of corticotropin-releasing factor (CRF) on the intracellular concentration of Ca2+ were studied in isolated single beta-cells of the rat islet. Immunohistochemical staining using CRF-receptor antibodies revealed the presence of both type 1 (CRF-R1) and type 2 (CRF-R2) receptors for CRF in the majority of islet cells. CRF (2 nmol/l) increased cytosolic Ca2+ concentration under 2.8 mmol/l glucose, dependent upon extracellular Ca2+. CRF caused depolarization of the cell membrane, which was followed by action potentials under 2.8 mmol/l glucose. The dose-response relationships of CRF-induced depolarization in the presence of 1 micromol/l nifedipine produced a bell-shaped curve, showing the peak response at 2 nmol/l. In the whole-cell patch-clamp recording, CRF enhanced Ca2+ currents through L-type Ca2+ channels in a dose-dependent manner similar to that for depolarization. In cells pretreated with Rp-deastereomer of adenosine cyclic 3',5'-phosphorothiolate (100 micromol/l), neither depolarization nor an increase in the Ca2+ current was caused by CRF at concentrations <2 nmol/l. In these cells, CRF at 20 nmol/l reduced the Ca2+ current. These results suggest that in single beta-cells of rat islets, CRF, through its own receptor, potentiates Ca2+ influx through the L-type Ca2+ channel by activation of the cAMP/protein kinase A signaling pathway. CRF at a high concentration also shows an inhibitory effect on the Ca2+ current through an unknown signaling pathway.


Asunto(s)
Calcio/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Animales , Inmunohistoquímica , Potenciales de la Membrana/efectos de los fármacos , Técnicas de Placa-Clamp , Ratas , Transducción de Señal/efectos de los fármacos
19.
Diabetes ; 45 Suppl 3: S62-4, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8674895

RESUMEN

We have previously reported that C-type natriuretic peptide (CNP), the third member of the natriuretic peptide family, is produced in vascular endothelial cells (ECs) and acts as an endothelium-derived relaxing peptide. We further demonstrated the detection of the gene transcripts of CNP and atrial natriuretic peptide (ANP) B receptor, a specific receptor for CNP, in human blood vessels. We thus propose the existence of a vascular natriuretic peptide system (NPS). CNP secretion was also demonstrated to be stimulated by various growth factors and cytokines. To clarify the significance of vascular NPS in proliferative vascular complications associated with diabetes, hypertension, or atherosclerosis, in the present study we examined the effect of insulin on CNP secretion from cultured ECs. Insulin at a concentration in the physiological range (10(-10)-10(-7) mol/l) potently suppressed CNP secretion, whereas insulin at the same concentration did not suppress endothelin (ET) secretion from EC. IGF-I had no significant effect on CNP secretion. Insulin, therefore, can be a potent inhibitor of CNP secretion through the activation of insulin receptor. Since CNP has been shown to be a potent inhibitor of vascular smooth muscle cell proliferation, the present study suggests the possibility that attenuated activity of vascular NPS is associated with hyperinsulinemia, which might result in proliferative vascular lesions.


Asunto(s)
Endotelio Vascular/metabolismo , Insulina/farmacología , Proteínas/metabolismo , Animales , Bovinos , Células Cultivadas , Endotelinas/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Péptido Natriurético Tipo-C , Tasa de Secreción/efectos de los fármacos
20.
Cell Signal ; 12(1): 63-70, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10676849

RESUMEN

We investigated the effect of intracellular cAMP on the gating kinetics of L-type Ca2+ channel in an A7r5 smooth muscle-derived cell line using the whole-cell patch-clamp technique. Application of dibutyryl cyclic AMP (db-cAMP) to the cell increased the magnitude of Ca2+ currents through L-type Ca2+ channels (I(Ca)), and shifted the current-voltage relationship (I-V curve) for I(Ca) to the left. The magnitudes of maximum I(Ca) were 14.1 +/- 0.7 before and 16.0 +/- 1.1 pA/pF after application of 1 mM db-cAMP (P < 0.05). The values of the half-activation potential (V(1/2)) of I(Ca), estimated from activation curves, were -7.0 +/- 0.8 mV before and -10.8 +/- 1.0 mV after application of db-cAMP (P < 0.05). In cells pretreated with 10 microM Rp-cAMPS (a specific inhibitor of PKA), db-cAMP affected neither the I-V curve nor the activation curve for I(Ca). In cells pretreated with the antisense oligonucleotide for the beta-subunit of L-type Ca2+ channel, db-cAMP failed to enhance I(Ca) or alter the activation curve. On the other hand, in the cells pretreated with the nonsense oligonucleotide, application of db-cAMP caused an increase in magnitude of I(Ca) and shifted the activation curve to the left. Western blot analysis revealed that the pretreatment of cells with antisense oligonucleotide but nonsense oligonucleotide reduced the expression of the beta-subunit of the L-type Ca2+ channel. We conclude that the cAMP-dependent phosphorylation of the beta-subunit potentiates the voltage dependency of the activation kinetics of the L-type Ca2+ channel in A7r5 cells.


Asunto(s)
Canales de Calcio Tipo L/metabolismo , Músculo Liso Vascular/metabolismo , Transducción de Señal , Animales , Línea Celular , AMP Cíclico/metabolismo , Activación del Canal Iónico , Fosforilación , Ratas
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