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1.
Appl Opt ; 55(5): 1164-9, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26906392

RESUMO

We demonstrate frequency offset locking between two laser sources using a waveguide-type electro-optic modulator (EOM) with 10th-order sidebands for magneto-optical trapping of Fr atoms. The frequency locking error signal was successfully obtained by performing delayed self-homodyne detection of the beat signal between the repumping frequency and the 10th-order sideband component of the trapping light. Sweeping the trapping-light and repumping-light frequencies with keeping its frequency difference of 46 GHz was confirmed over 1 GHz by monitoring the Doppler absorption profile of I2. This technique enables us to search for a resonance frequency of magneto-optical trapping of Fr.

2.
J Exp Med ; 181(3): 1027-36, 1995 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7532674

RESUMO

Autoantibodies specific against fibrillarin, a 34-kD nucleolar protein associated with U3-snRNP, are present in patients with systemic sclerosis (SSc). To understand the mechanisms involved in the induction of these autoantibodies, we prepared a series of human fibrillarin recombinant proteins covering the entire molecule and analyzed their interaction with the autoantibodies present in various connective tissue diseases. Our results showed that antifibrillarin autoantibodies are present not only in SSc, as previously reported, but also in a variety of other connective tissue diseases. Patients with SSc (58%), mixed connective tissue diseases (60%), CREST syndrome (calcinosis, Raynaud phenomenon, esophageal dismotility, sclerodactyly, and telangiectasia syndrome) (58%), systemic lupus erythematosus (39%), rheumatoid arthritis (60%), and Sjogern's syndrome (84%) showed presence of antifibrillarin autoantibodies. Results obtained from competitive inhibition radioimmunoassay and Western blot analyses with purified recombinant fusion proteins revealed that these autoantibodies react primarily with epitope(s) present in the NH2- (AA 1-80) and COOH-terminal (AA 276-321) domains of fibrillarin. Autoantibodies reacting with internal regions of fibrillarin are less frequent. Analysis of the hydrophilicity profiles of reactive peptides showed presence of three potential antigenic sites in the NH2- and two in the COOH-terminal regions. While a hexapeptide sequence NH2 terminus of fibrillarin is shared with an Epstein-Barr virus-encoded nuclear antigen, the COOH-terminal region shares sequence homology with P40, the capsid protein encoded by herpes virus type 1. Interestingly, these two regions of fibrillarin also contain the most immunodominant sequences, as predicted by surface probability and the Jameson and Wolf antigenic index. These observations suggest that molecular mimicry might play an important role in the induction of antifibrillarin autoantibodies.


Assuntos
Autoanticorpos/análise , Proteínas Cromossômicas não Histona/imunologia , Doenças do Tecido Conjuntivo/imunologia , Epitopos , Escleroderma Sistêmico/imunologia , Sequência de Aminoácidos , Especificidade de Anticorpos , Sequência de Bases , Proteínas Cromossômicas não Histona/biossíntese , Imunofluorescência , Humanos , Dados de Sequência Molecular , Radioimunoensaio , Proteínas Recombinantes/biossíntese
3.
Curr Top Microbiol Immunol ; 210: 299-306, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8565570

RESUMO

The possible role of silicone in the pathogenesis of a scleroderma-like syndrome is still unresolved. It has been proposed that silicone escaping from breast implants potentiates the progression of the disease. To clarify whether silicone enhances development of fibrotic skin lesions and autoantibodies, we tested its effect on tight skin (TSK/+) mice. TSK/+ mice spontaneously develop skin fibrosis and characteristic autoantibodies which resemble human scleroderma. The results of the present study indicate that silicone administration does not enhance development of skin fibrosis nor synthesis of autoantibodies to RNA polymerase and topoisomerase in TSK/+ mice.


Assuntos
Escleroderma Sistêmico/etiologia , Silicones/toxicidade , Animais , Autoanticorpos/sangue , Camundongos , Pele/patologia
4.
Neurology ; 49(3): 870-1, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9305356

RESUMO

The virus-associated hemophagocytic syndrome (VAHS) is a lymphoproliferative disorder induced by viral infection. The peripheral nervous system is rarely involved in this syndrome and, when reported, the involvement has been axonal in nature. This paper presents a case of Guillain-Barré syndrome accompanied by VAHS subsequent to Epstein-Barr virus infection. The patient's condition improved following treatment with intravenous immunoglobulin infusion and high-dose corticosteroids.


Assuntos
Infecções por Herpesviridae/complicações , Herpesvirus Humano 4 , Transtornos Linfoproliferativos/etiologia , Polirradiculoneuropatia/etiologia , Corticosteroides/uso terapêutico , Idoso , Medula Óssea/patologia , Histiocitose/patologia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Transtornos Linfoproliferativos/terapia , Masculino , Infecções Tumorais por Vírus/complicações
5.
Am J Med ; 91(4): 355-62, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1951379

RESUMO

PURPOSE: The role that circulating anti-DNA immune complexes play in autoimmunity has not yet been elucidated in humans. The aim of this study was to relate circulating anti-DNA immune complexes to a variety of renal histologic features and to immunoglobulin deposits in active lupus nephritis. PATIENTS AND METHODS: The study population consisted of 47 patients with active lupus nephritis, 28 with active systemic lupus erythematosus (SLE) in the absence of renal lesions, and 40 with other categories of the disease. All patients were examined for anti-DNA circulating immune complexes (CIC) and their anti-DNA idiotype expression by an isoelectrofocusing analysis. Patients with renal lesions were also examined for renal histologic and immunofluorescent findings in renal biopsy specimens. RESULTS: Anti-DNA CIC expressing an anti-DNA idiotype termed 0-81 Id occurred in patients with active lupus nephritis but not in acute episodes lacking renal involvement or in remission. Positive test results for anti-DNA CIC were associated with the incidence of diffuse proliferative glomerulonephritis (DPGN). Patients with anti-DNA CIC were also found to have a statistically significant increase in the prevalence of immunoglobulin immune deposits in the subendothelial area of the renal glomeruli. CONCLUSION: The findings suggest that anti-DNA CIC preferentially occurred in lupus patients with DPGN. Examination for anti-DNA CIC may be a useful predictor of renal lesions, and therefore may contribute to the management of SLE. The results also indicate that anti-DNA CIC may be associated with immunoglobulin deposition in the subendothelial area of the renal glomeruli.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Antinucleares/imunologia , Complexo Antígeno-Anticorpo/imunologia , Imunoglobulina G , Nefrite Lúpica/imunologia , Adolescente , Adulto , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Antinucleares/sangue , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo/sangue , Biópsia , Feminino , Humanos , Incidência , Focalização Isoelétrica , Nefrite Lúpica/epidemiologia , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência
6.
Int Rev Immunol ; 13(4): 317-25, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8884428

RESUMO

Tdt deficient mice show lack of N region in V(D)J junctions of immunoglobulin and T cell receptor genes and revealed that "immature recombinase" in fetal stage would boil down to no more than a lack of Tdt. Although particular junctions which are thought to be created by homology-mediated joining are frequently observed, one fourth of junctions lacked even one bp of overlap, indicating the existence of a V(D)J joining pathway that is homology independent. Lymphocyte repertoire which express VH81X gene without N region is negatively selected, which shows that the repertoire of Tdt deficient mice is not a truly fetal repertoire. Positive selection of thymocytes is more efficient in Tdt deficient mice. Furthermore Tdt-/- mice produce significant amounts of anti-dsDNA antibodies as Tdt+/+ mice, indicating that increased diversity of the third complementarity-determining region (CDR3) by Tdt is not essential for the expansion of precursor B cells programmed to produce anti-DNA antibodies.


Assuntos
DNA Nucleotidilexotransferase/deficiência , Linfócitos T/fisiologia , Animais , Autoanticorpos/biossíntese , Camundongos , Receptores de Antígenos de Linfócitos T/genética
7.
Autoimmunity ; 20(2): 113-20, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7578867

RESUMO

The kappa chain deficient mouse strain represents an excellent experimental system for studying the contribution of lambda light chains to the antibody repertoire. Here, we have studied the contribution of lambda chains to the generation of self reactive antibodies including RFs in kappa deficient mice with 129/sv background. These mutant mice produce rheumatoid factors similar to 129/sv mice and these antibodies are primarily encoded by lambda 2. This may be due to the production of RF by peritoneal B lymphocytes which belong to Ly1 B subset. Peritoneal B cell selectively produce lambda 2 and lambda 3 isotypes. Though lambda 1 positive RF is not detectable in the sera, lambda 1 positive specific precursor B cells are present in these mice and they can be activated by T-independent antigens. Our studies show that these mice also spontaneously produce anti-dsDNA antibodies bearing lambda 1 light chain but do not produce self reactive antibodies specific for eight different autoantigens. However, B cell precursors expressing lambda chains specific for autoantigens like collagen II, III, IV and histone 2A are present in the B cell repertoire of kappa-deficient mice. Thus, our results demonstrate that lambda light chain can compensate, to some extent, the lack of kappa chain repertoire, not only against foreign antigens, as observed previously, but also against a number of autoantigens.


Assuntos
Autoanticorpos/sangue , Cadeias kappa de Imunoglobulina/genética , Síndromes de Imunodeficiência/genética , Envelhecimento/genética , Envelhecimento/imunologia , Animais , Antígenos T-Independentes/farmacologia , Hemocianinas/imunologia , Síndromes de Imunodeficiência/imunologia , Cinética , Camundongos , Camundongos Mutantes , Fosforilcolina/imunologia , Fator Reumatoide/biossíntese , Fator Reumatoide/sangue
8.
Phys Rev Lett ; 84(7): 1407-10, 2000 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-11017529

RESUMO

At temperatures below 2.1 K, long-lived gaseous Rb atoms in glass cells have been generated with a simple method: irradiating the cells, containing 4He gas and Rb metal, with a cw laser. The obtained atomic Rb density ( approximately 10(8) cm(-3)) decreases with a 1/e time constant of about 10 s at 1.85 K. We have performed optical pumping of the Rb atoms and measured the longitudinal electronic spin relaxation time at 1.85 K as well. For processes (such as Rb-He collisions) which do not remove the atomic Rb from the vapor, this relaxation time is found to be about 60+/-15 s.

9.
Am J Ophthalmol ; 132(2): 280-2, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11476704

RESUMO

PURPOSE: We present favorable results with amniotic membrane transplantation in a patient who developed fat adherence syndrome after retinal surgery. DESIGN: Interventional case report. METHODS: A 37-year-old man had diplopia resulting from hypotropia of the left eye after retinal detachment surgery. Removal of a previously implanted silicon sponge had little effect because of fibrous adhesion between the inferior rectus muscle and adjacent periorbital fat. We performed amniotic membrane transplantation combined with conventional extraocular muscle surgery. RESULTS: Postoperatively, supraduction of the left eye became almost full. The field of binocular vision was extended markedly by treatment, both in the primary position and with downward gaze. These improvements remained stable over 1 year of follow-up. CONCLUSION: Amniotic membrane transplantation appears to be effective for preventing regrowth of restrictive scar tissue in the fat adherence syndrome.


Assuntos
Tecido Adiposo/cirurgia , Âmnio/transplante , Músculos Oculomotores/cirurgia , Doenças Orbitárias/cirurgia , Complicações Pós-Operatórias/cirurgia , Descolamento Retiniano/cirurgia , Tecido Adiposo/patologia , Adulto , Diplopia/etiologia , Diplopia/cirurgia , Humanos , Masculino , Transtornos da Motilidade Ocular/etiologia , Transtornos da Motilidade Ocular/cirurgia , Doenças Orbitárias/etiologia , Complicações Pós-Operatórias/patologia , Síndrome , Aderências Teciduais/cirurgia , Visão Binocular
10.
Intern Med ; 32(1): 50-2, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8495045

RESUMO

A 39-year-old woman presented clinical features of adult onset Still's disease. Seven years after the onset, she developed renal insufficiency and biopsy studies revealed amyloid deposits involving amyloid A protein, P component, lambda chain and kappa chain in the kidney and rectum. She died in 1992, primarily due to cardiac failure associated with amyloidosis, indicating that amyloidosis should be considered one of the fatal complications in adult onset Still's disease with a long history.


Assuntos
Amiloidose/etiologia , Doença de Still de Início Tardio/complicações , Adulto , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/patologia , Feminino , Humanos , Prognóstico
11.
J Nutr Sci Vitaminol (Tokyo) ; 47(4): 311-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11767213

RESUMO

The purpose of the current study was to assess the involvement of the branched-chain amino acid leucine in the regulation of translation initiation in the liver and to compare the time course of leucine action on the translation initiation in the liver and skeletal muscle of rats. The phosphorylation of the eukaryotic initiation factor (eIF)4E-binding protein 1 (4E-BP1) frees eIF4E and stimulates protein synthesis by accelerating translation initiation. Phosphorylation of the 70-kDa ribosomal protein S6 kinase (S6K) is thought to be involved in regulating the synthesis of certain ribosomal proteins and other selected proteins with polypyrimidine clusters near the transcription start site. Food-deprived (18 h) male rats were orally administered 135 mg/100 g body weight L-leucine and sacrificed at 0, 1, 3, or 6 h after administration. The oral administration of leucine resulted in an enhanced phosphorylation of 4E-BP1 and S6K1 in both the liver and skeletal muscle. A time-dependent change in the phosphorylation state of 4E-BP1 and S6K1 was more acute in the skeletal muscle than in the liver and closely paralleled the changes in plasma leucine concentration. Our results indicate that the primary mediator in 4E-BP1 phosphorylation and S6K1 phosphorylation by the oral administration of leucine is an increase in the plasma concentration of leucine. Furthermore, our findings suggest differential sensitivity in the tissue response to oral administration of leucine.


Assuntos
Proteínas de Transporte/fisiologia , Leucina/administração & dosagem , Fígado/fisiologia , Músculo Esquelético/fisiologia , Fosfoproteínas/fisiologia , Fosfotransferases/fisiologia , Proteínas Quinases S6 Ribossômicas/fisiologia , Administração Oral , Animais , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Fosforilação , Ratos , Ratos Wistar , Fatores de Tempo
12.
Adv Perit Dial ; 8: 116-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1361765

RESUMO

Pseudotumor of the craniocervical junction and destructive spondyloarthropathy (DSA) are the most serious forms of dialysis amyloidosis (DAA). Pain and paralysis due to these lesions significantly impair activity of a patients' daily life (ADL). CAPD improved ADL of a 54 year-old male patient complicated with various forms of DAA after 17 years of hemodialysis (HD) treatment. He was first diagnosed as having carpal tunnel syndrome 12 years after initiation of hemodialysis followed by dialysis shoulders(12 years), trigger fingers(12 years), bone cysts(15 years), tendon ruptures(17 years), DSA and a pseudotumor of the craniocervical junction(17 years). Magnetic resonance imaging (MRI) taken in May 1989 revealed a pseudotumor of the craniocervical junction, which was 30 mm in diameter, located in front of partially destroyed C1 and C2. Neck pain and muscle weakness rendered him bed ridden. Six months after switching to CAPD with administration of prednisolone, neck pain disappeared. He recovered the muscle power by physical rehabilitation. At last it became possible for him to perform the CAPD procedure by himself and drive a car to the hospital as an out patient. In such cases of pseudotumors of the craniocervical junction, CAPD is one of the best methods for relieving the pain and muscle weakness.


Assuntos
Atividades Cotidianas , Vértebras Cervicais , Processo Odontoide , Diálise Peritoneal Ambulatorial Contínua , Diálise Renal/efeitos adversos , Amiloidose/etiologia , Vértebras Cervicais/patologia , Humanos , Falência Renal Crônica/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pescoço/patologia , Processo Odontoide/patologia , Dor/etiologia , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/etiologia
13.
Rev Sci Instrum ; 85(2): 02A732, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593466

RESUMO

The search for the violation of the fundamental symmetry in a radioactive atom is the promising candidate for precision tests of the standard model and its possible extensions. The subtle signal arising from the symmetry violation is enhanced in heavy atoms, such as a francium (Fr). To realize high precision measurements, a large amount of radioactive isotopes is required. The Fr is produced via a nuclear fusion reaction using a melted gold target with a (18)O primary beam at Cyclotron and Radioisotope Center, Tohoku University. The maximum extraction efficiency of the Fr ion was achieved at approximately 35%. The beam line consists of an electrostatic deflector, three electrostatic quadrupole triplets to the measurement area at 10 m away from the reaction point, and several beam diagnosis systems. We optimized parameters of the beam line.

16.
Phys Rev Lett ; 102(8): 085502, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19257752

RESUMO

We present an experimental demonstration of an ingenious technique to control the alignment of the atomic internal state in the x-ray region using a periodic crystal field. The alignment directions of Ar16+ and Fe24+ ions were readily controlled by selecting the array of atomic planes using three-dimensional resonant coherent excitation, and were probed via the anisotropy of the deexcitation x-ray emission. We applied this method to a double resonance experiment, and succeeded in controlling the population of the specific magnetic substate in a Lambda-type three-level configuration.

17.
Phys Rev Lett ; 101(11): 113201, 2008 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-18851279

RESUMO

We report the Autler-Townes doublet demonstrating a novel type of coherent interaction of atoms not with photons but with a periodic crystal field when the atom is in flight through a crystal at high velocity. It was observed by the nonoptical X-VUV (vacuum-ultraviolet) double resonance of three-dimensional resonant coherent excitation with good coherence. The states strongly coupled in the VUV region were probed by the excitation in the x-ray region. The characteristic spectra are well interpreted by an analogy of the dressed atom concept often adopted for the atom-photon interaction.

18.
Phys Rev Lett ; 96(9): 095301, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16606273

RESUMO

The longitudinal electronic spin relaxation time of Cs atoms optically polarized in superfluid helium (He II, 1.5 K) has been measured with special care to cope with a serious decrease in the number of Cs atoms in the observation region. This decrease, mainly caused by helium convection in introducing the atoms into He II by laser sputtering, was significantly reduced using a new atom implantation method. Combined with a careful correction for the number of atoms, we have determined the relaxation time to be 2.24(19) s or longer, roughly twice as long as that in solid He.

19.
Phys Rev Lett ; 97(13): 135503, 2006 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-17026044

RESUMO

We have observed resonant coherent excitation (RCE) of H-like Ar(17+) ions traveling through a 1 microm-thick Si crystal at an energy of 391 MeV/u in the nonchanneling condition. A three-dimensional periodic array of atomic planes induces RCE of the nonchanneling ions. The high energy heavy ions together with the thin crystal allow us to observe this new RCE through the measurements of the charge-state distribution of the emerging ions. The observed resonances are much narrower than those of planar-channeling ions due to the absence of the large Stark shift caused by the planar potential.

20.
Phys Rev Lett ; 95(25): 253003, 2005 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-16384456

RESUMO

We demonstrate that transitions between Zeeman-split sublevels of Rb atoms are resonantly induced by the motion of the atoms (velocity: approximately 100 m/s) in a periodic magnetostatic field (period: 1 mm) when the Zeeman splitting corresponds to the frequency of the magnetic field experienced by the moving atoms. A circularly polarized laser beam polarizes Rb atoms with a velocity selected using the Doppler effect and detects their magnetic resonance in a thin cell, to which the periodic field is applied with the arrays of parallel current-carrying wires.

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