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1.
Phys Rev Lett ; 110(23): 237003, 2013 Jun 07.
Article in English | MEDLINE | ID: mdl-25167525

ABSTRACT

We theoretically study spin current through ferromagnet (F) in a Josephson junction composed of s-wave superconductors and two layers of ferromagnets. Using quasiclassical theory, we show that the long-range spin current can be driven by the superconducting phase difference without a voltage drop. The origin of this spin current is due to spin-triplet Cooper pairs (STCs) formed by electrons of equal spin, which are induced by the proximity effect inside the F. We find that the spin current carried by the STCs exhibits long-range propagation in the F even where the Josephson charge current is practically zero. We also show that this spin current persists over a remarkably longer distance than the ordinary spin current carried by spin polarized conduction electrons in the F. Our results thus indicate the promising potential of Josephson junctions based on multilayer ferromagnets for spintronics applications with long-range propagating spin current.

2.
J Perinatol ; 31(4): 246-50, 2011 Apr.
Article in English | MEDLINE | ID: mdl-20706192

ABSTRACT

OBJECTIVE: The aim of this study was to assess the genetic effects of the vascular endothelial growth factor (VEGF) pathway on retinopathy of prematurity (ROP). STUDY DESIGN: A prospective study from a tertiary center that enrolled 204 Japanese infants (<35 weeks of gestational age (GA)) having no anomalies. ROP developed in 127, but not in 77 infants. The relative severity was defined as non-severe, moderate and severe ROP for GA, based on the staging criteria. VEGF (g.-634G>C, g.+13553C>T) and VEGF-receptor (KDR g.+4422(AC)11 to 14, Flt-1 c.+6724(TG)13 to 23) gene polymorphisms and clinical variables were assessed by uni/multivariate analyses. RESULT: The frequency of polymorphisms did not differ between ROP and non-ROP patients. The TT genotype of g.+13553 showed a higher odds ratio for non-severe ROP than CC genotype (P=0.006). Multivariate analyses indicated that low birth weight, blood transfusion and respiratory distress syndrome, but not polymorphisms, were the risk factors of advanced ROP (≥ stage 3). CONCLUSION: A genotype of the VEGF pathway weakly affects the severity of ROP compared with other clinical factors.


Subject(s)
Infant, Low Birth Weight , Respiratory Distress Syndrome, Newborn/complications , Retinopathy of Prematurity , Transfusion Reaction , Vascular Endothelial Growth Factor Receptor-1 , Female , Genotype , Gestational Age , Humans , Infant, Newborn , Infant, Premature , Male , Polymorphism, Genetic , Premature Birth/physiopathology , Premature Birth/therapy , Prospective Studies , Retinopathy of Prematurity/complications , Retinopathy of Prematurity/genetics , Retinopathy of Prematurity/physiopathology , Risk Factors , Severity of Illness Index , Vascular Endothelial Growth Factor A
3.
Phys Rev Lett ; 99(5): 057003, 2007 Aug 03.
Article in English | MEDLINE | ID: mdl-17930781

ABSTRACT

A Josephson current through a half-metallic ferromagnet between two conventional superconductors is theoretically studied. The spin dynamics such as magnon excitation plays a crucial role not only for the conversion between spin-singlet and spin-triplet pairs but also for the formation of the composite state of a triplet Cooper pair and magnon, by which the Josephson current flows between the superconductors. We propose the supercurrent pumping driven by the coherent precession of the magnetization by tuning the microwave frequency to the ferromagnetic resonance frequency in a ferromagnetic Josephson junction.

4.
Clin Exp Immunol ; 138(1): 47-53, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15373904

ABSTRACT

To continue the search for immunological roles of breast milk, cDNA microarray analysis on cytokines and growth factors was performed for human milk cells. Among the 240 cytokine-related genes, osteopontin (OPN) gene ranked top of the expression. Real-time PCR revealed that the OPN mRNA levels in colostrum cells were approximately 100 times higher than those in PHA-stimulated peripheral blood mononuclear cells (PBMNCs), and 10 000 times higher than those in PB CD14(+) cells. The median levels of OPN mRNA in early milk or mature milk cells were more than three times higher than those in colostrum cells. Western blot analysis of human milk showed appreciable expression of full-length and short form proteins of OPN. The concentrations of full-length OPN in early milk or mature milk whey continued to be higher than those in colostrum whey and plasma as assessed by ELISA. The early milk (3-7 days postpartum) contained the highest concentrations of OPN protein, while the late mature milk cells (1 years postpartum) had the highest expression of OPN mRNA of all the lactating periods. The results of immunohistochemical and immunocytochemical staining indicated that OPN-producing epithelial cells and macrophages are found in actively lactating mammary glands. These results suggest that the persistently and extraordinarily high expression of OPN in human milk cells plays a potential role in the immunological development of breast-fed infants.


Subject(s)
Lactation/immunology , Milk, Human/immunology , Oligonucleotide Array Sequence Analysis/methods , Sialoglycoproteins/analysis , Blotting, Western/methods , Cells, Cultured , Colostrum/chemistry , Colostrum/immunology , Cytokines/genetics , Cytokines/immunology , Enzyme-Linked Immunosorbent Assay/methods , Female , Growth Substances/genetics , Growth Substances/immunology , Humans , Immunohistochemistry/methods , Leukocytes, Mononuclear/chemistry , Leukocytes, Mononuclear/immunology , Milk, Human/cytology , Osteopontin , Pregnancy , RNA, Messenger/analysis
5.
Pediatr Res ; 50(6): 732-6, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11726732

ABSTRACT

GH and IGF-I are important for physical growth. We measured serum levels of these factors in preterm infants. The study population (n = 81) was divided into three groups according to the gestational age. We evaluated differences in serum GH and IGF-I levels among groups with regard to physical growth and development of retinopathy of prematurity. Serum GH levels in extremely preterm infants born at <28 wk of gestational age were significantly higher than levels in those born between 28 and 34 wk at 1 and 2 mo of age. In contrast, serum IGF-I levels in extremely preterm infants remained low, whereas those in the other two groups gradually increased. Evaluation of the effects of GH and IGF-I on physical growth in very low birth weight infants (<1500 g) showed that IGF-I concentrations were positively related to physical growth for several months after birth, whereas no relationship was observed between GH and physical growth. Multivariate analysis demonstrated that high GH concentration at 1 mo of age was significantly associated with development of severe retinopathy of prematurity. In conclusion, persistent low serum IGF-I levels may explain the slow physical growth during neonatal life, and exposure of high GH may cause, at least in part, severe retinopathy of prematurity in preterm infants.


Subject(s)
Growth/physiology , Human Growth Hormone/physiology , Infant, Premature/growth & development , Insulin-Like Growth Factor I/physiology , Retinopathy of Prematurity/physiopathology , Disease Progression , Female , Human Growth Hormone/blood , Humans , Infant, Newborn , Infant, Premature/blood , Insulin-Like Growth Factor I/metabolism , Longitudinal Studies , Male , Regression Analysis , Retinopathy of Prematurity/blood , Risk Factors
6.
J Clin Neurosci ; 8(6): 586-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11683616

ABSTRACT

Two cases with posterior protruding cervical dysraphic lesions are presented; neuroimaging and clinical features of this rare clinical entity are discussed.


Subject(s)
Meningomyelocele/pathology , Meningomyelocele/surgery , Spinal Dysraphism/pathology , Spinal Dysraphism/surgery , Cervical Vertebrae , Female , Humans , Infant , Magnetic Resonance Imaging
7.
Pediatr Neurol ; 25(3): 236-8, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11587879

ABSTRACT

Multiple cerebral arteriovenous fistulas with malformations in the fetus or neonate are rare. Here we describe a patient who had these lesions with pulmonary stenosis, resulting in severe brain atrophy in utero and intractable heart failure after birth. The pathophysiology of this patient is discussed in hemodynamic terms.


Subject(s)
Abnormalities, Multiple , Arteriovenous Fistula/congenital , Brain/pathology , Heart Failure/etiology , Intracranial Arteriovenous Malformations/diagnosis , Arteriovenous Fistula/complications , Atrophy , Brain/blood supply , Fatal Outcome , Female , Hemodynamics , Humans , Infant, Newborn , Magnetic Resonance Angiography , Pulmonary Valve Stenosis/diagnosis
8.
Acta Paediatr ; 90(8): 850-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11529529

ABSTRACT

UNLABELLED: The prevalence rates of food allergy and atopic dermatitis in low birthweight infants were evaluated. In Fukuoka City, Japan, between July 1994 and September 1997, sufficient information including birthweight, gestational age, sex, feeding method and a history of food allergy was obtained from questionnaires at the well-baby check-ups of 21766 infants (18 mo of age) and 4378 children (3 y of age). All the children were examined by pediatricians with regard to the existence of atopic dermatitis. The prevalence rate (8.1%) of food allergy in infants with low birthweight (<2,500 g) was significantly lower than that (11.2%) in infants with normal birthweight (> or = 2,500 g) at 18 mo of age (p = 0.0002). Atopic dermatitis was also observed at a lower prevalence rate (1.2%) in infants with low birthweight than in those with normal birthweight (2.3%) at the same age (p = 0.0041). However, this significance was lost at 3 y of age. Other characteristics including male sex and breast-feeding showed independent risks for the development of food allergy and atopic dermatitis at both ages. CONCLUSION: This study found that low birthweight was significantly associated with a lower risk of both food allergy and atopic dermatitis at 18 mo of age.


Subject(s)
Dermatitis, Atopic/epidemiology , Food Hypersensitivity/epidemiology , Breast Feeding , Child, Preschool , Female , Humans , Infant , Infant, Low Birth Weight , Infant, Newborn , Japan/epidemiology , Male , Prevalence , Sex Factors , Surveys and Questionnaires
9.
Ryoikibetsu Shokogun Shirizu ; (33): 370-1, 2001.
Article in Japanese | MEDLINE | ID: mdl-11462480
10.
No To Shinkei ; 53(11): 1045-9, 2001 Nov.
Article in Japanese | MEDLINE | ID: mdl-11761914

ABSTRACT

We report 2 infants who were born as one of monochorial twins. Both of them had been suffering from twin-twin transfusion syndrome(TTTS) as a donor fetus. Case 1 was delivered by caesarean section at the 28th week of pregnancy. On day 0, intraventricular hemorrhage(IVH) occurred from the right subependymal germinal matrix layer, and progressive ventricular enlargement was followed. Case 2 was delivered by the caesarean section at the 31st week of pregnancy. On day 9, he developed IVH from the choroid plexus at the trigone of the left lateral ventricle, and progressive enlargement of the inferior and posterior horns, trigone and posterior part of the body of the left lateral ventricle was followed. IVH in patients with TTTS usually occur in recipient infant but it can also occur in donor infant as in our cases. Pathophysiology of central nervous system damages associated with TTTS is variable and complicated.


Subject(s)
Cerebral Hemorrhage/complications , Diseases in Twins , Fetofetal Transfusion/complications , Hydrocephalus/etiology , Cerebral Ventricles , Female , Humans , Infant, Newborn , Male , Pregnancy , Twins, Monozygotic
11.
J Inherit Metab Dis ; 23(6): 583-92, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11032333

ABSTRACT

We investigated the quantitative expression of the human glucose-6-phosphate translocase gene (G6PT1) and its splicing variants in human tissues. The G6PT1 gene was strongly expressed in liver, kidney and haematopoietic progenitor cells, which might explain major clinical symptoms such as hepatomegaly, nephromegaly and neutropenia in glycogen storage diseases type Ib. Reverse transcriptase-mediated PCR amplification of G6PT1 cDNA revealed several splicing variants in tissue-specific manners. The brain-specific isoform, which has an additional 22 amino acids between exons 6 and 8, was also identified in heart and skeletal muscle. A new splicing variant, although less prominent in quantity and lacking polypeptide loops corresponding to exons 2 and 3, may have a distinct substrate affinity or specificity in leukocytes and haematopoietic progenitors. In conclusion, the G6PT1 gene was expressed in various tissues, and alternative splicing variants exist in tissue-specific manners.


Subject(s)
Gene Expression , Hematopoietic Stem Cells/enzymology , Organ Specificity , Phosphotransferases/genetics , Adolescent , Adult , Aged , Alternative Splicing , Antiporters , Brain/enzymology , Child , Female , Fetus , Humans , Isoenzymes/genetics , Kidney/embryology , Kidney/enzymology , Leukocytes/enzymology , Liver/embryology , Liver/enzymology , Male , Middle Aged , Monosaccharide Transport Proteins , Muscle, Skeletal/enzymology , Myocardium/enzymology , Pancreas/enzymology , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA
12.
Acta Paediatr ; 88(1): 24-8, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10090542

ABSTRACT

To search for an efficient method of management of non-immune hydrops fetalis (NIHF), the clinical outcome of 51 newborns with NIHF was retrospectively assessed in a single centre. As the short-term outcome, the mortality rate was mainly dependent on the causes of NIHF and the presence of pleural effusion. The survival rate of the patients with pleural effusion (7/28; 25%) was significantly lower than that of those without it (14/23; 61%) (p < 0.02). All 7 survivors with pleural effusion were diagnosed antenatally after 29 weeks of gestation and were delivered after 31 weeks of gestation. With respect to the long-term outcome, 13 (68.4%) of 19 patients who survived beyond 1 y of age showed normal development, 2 mild developmental delay at 1 y of age and 1 mental retardation at 8 y of age, while 3 (15.8%) had severe psychomotor retardation with marked growth failure. Two of these three patients were born as very-low-birthweight infants. The follow-up results indicate that pleural drainage in utero and prevention of premature delivery should be proposed to improve the outcome of NIHF patients.


Subject(s)
Hydrops Fetalis/therapy , Female , Gestational Age , Humans , Hydrops Fetalis/complications , Hydrops Fetalis/mortality , Infant, Newborn , Male , Pleural Effusion/complications , Psychomotor Performance , Retrospective Studies , Survival Analysis
13.
Eur J Pediatr ; 153(9): 687-90, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7957431

ABSTRACT

We describe two Japanese children with idiopathic pulmonary haemosiderosis (IPH), whose refractory haemorrhages were treated with an intravenous lipid emulsion containing dexamethasone (liposteroid). A 22-month-old boy and a 14-month-old girl have been observed with similar symptoms; periodic bouts of anaemia, reticulocytosis, diffuse infiltrates on chest X-ray and the finding of siderophages in sputum or gastric lavage fluid. The MRI of the lung was useful for the diagnosis. Methylprednisolone pulse therapy was successful in treating acute massive bleeding. Subsequent oral prednisolone could not prevent chronic recurrent haemorrhages. However, the intermittent administration of liposteroid (0.05 mg/kg/dose IV) led to a cessation of bleeding; the haemoglobin concentration rose to normal levels. This observation emphasizes the usefulness of liposteroid in the management of refractory IPH.


Subject(s)
Dexamethasone/therapeutic use , Hemorrhage/complications , Hemosiderosis/complications , Hemosiderosis/drug therapy , Lung Diseases/complications , Female , Hemorrhage/drug therapy , Hemosiderosis/diagnosis , Humans , Infant , Lung Diseases/drug therapy , Male , Methylprednisolone/therapeutic use , Recurrence
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