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1.
Nat Mater ; 23(5): 627-632, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38321239

RESUMO

When excited, the magnetization in a magnet precesses around the field in an anticlockwise manner on a timescale governed by viscous magnetization damping, after which any information carried by the initial actuation seems to be lost. This damping appears to be a fundamental bottleneck for the use of magnets in information processing. However, here we demonstrate the recall of the magnetization-precession phase after times that exceed the damping timescale by two orders of magnitude using dedicated two-colour microwave pump-probe experiments for a Y3Fe5O12 microstructured film. Time-resolved magnetization state tomography confirms the persistent magnetic coherence by revealing a double-exponential decay of magnetization correlation. We attribute persistent magnetic coherence to a feedback effect, that is, coherent coupling of the uniform precession with long-lived excitations at the minima of the spin-wave dispersion relation. Our finding liberates magnetic systems from the strong damping in nanostructures that has limited their use in coherent information storage and processing.

2.
Allergy ; 73(2): 395-404, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28914974

RESUMO

BACKGROUND: Our genomewide association study documented an association between cold medicine-related Stevens-Johnson syndrome/toxic epidermal necrolysis (CM-SJS/TEN) and Ikaros Family Zinc Finger 1 (IKZF1). Few studies examined biological and pathological functions of IKZF1 in mucosal immunity. We hypothesized that IKZF1 contributes to the mucocutaneous inflammation. METHODS: Human skin and conjunctival tissues were obtained for immunohistological studies. Primary human conjunctival epithelial cells (PHCjECs) and adult human epidermal keratinocytes (HEKa) also used for gene expression analysis. We also generated K5-Ikzf1-EGFP transgenic mice (Ikzf1 Tg) by introducing the Ik1 isoform into cells expressing keratin 5, which is expressed in epithelial tissues such as the epidermis and conjunctiva, and then examined them histologically and investigated gene expression of the epidermis. Moreover, Ikzf1 Tg were induced allergic contact dermatitis. RESULTS: We found that human epidermis and conjunctival epithelium expressed IKZF1, and in PHCjECs and HEKa, the expression of IKZF1 mRNA was upregulated by stimulation with polyI:C, a TLR3 ligand. In Ikzf1 Tg, we observed dermatitis and mucosal inflammation including the ocular surface. In contact dermatitis model, inflammatory infiltrates in the skin of Ikzf1 Tg were significantly increased compared with wild type. Microarray analysis showed that Lcn2, Adh7, Epgn, Ifi202b, Cdo1, Gpr37, Duoxa1, Tnfrsf4, and Enpp5 genes were significantly upregulated in the epidermis of Ikzf1 Tg compared with wild type. CONCLUSION: Our findings support the hypothesis that Ikaros might participate in mucocutaneous inflammation.


Assuntos
Fator de Transcrição Ikaros/genética , Inflamação/imunologia , Queratina-5/imunologia , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/imunologia , Animais , Modelos Animais de Doenças , Humanos , Fator de Transcrição Ikaros/imunologia , Inflamação/genética , Queratina-5/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Reação em Cadeia da Polimerase , Pele/imunologia
3.
Phys Rev Lett ; 110(25): 255001, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23829741

RESUMO

We report simulation results for turbulent magnetic reconnection obtained using a newly developed Reynolds-averaged magnetohydrodynamics model. We find that the initial Harris current sheet develops in three ways, depending on the strength of turbulence: laminar reconnection, turbulent reconnection, and turbulent diffusion. The turbulent reconnection explosively converts the magnetic field energy into both kinetic and thermal energy of plasmas, and generates open fast reconnection jets. This fast turbulent reconnection is achieved by the localization of turbulent diffusion. Additionally, localized structure forms through the interaction of the mean field and turbulence.

4.
Genes Immun ; 13(2): 139-45, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21918539

RESUMO

Although the MHC class II 'u' haplotype is strongly associated with type 1 diabetes (T1D) in rats, the role of MHC class II in the development of tissue-specific autoimmune diseases including T1D and autoimmune thyroiditis remains unclear. To clarify this, we produced a congenic strain carrying MHC class II 'a' and 'u' haplotypes on the Komeda diabetes-prone (KDP) genetic background. The u/u homozygous animals developed T1D similar to the original KDP rat; a/u heterozygous animals did develop T1D but with delayed onset and low frequency. In contrast, none of the a/a homozygous animals developed T1D; about half of the animals with a/u heterozygous or a/a homozygous genotypes showed autoimmune thyroiditis. To investigate the role of genetic background in the development of thyroiditis, we also produced a congenic strain carrying Cblb mutation of the KDP rat on the PVG.R23 genetic background (MHC class II 'a' haplotype). The congenic rats with homozygous Cblb mutation showed autoimmune thyroiditis without T1D and slight to severe alopecia, a clinical symptom of hypothyroidism such as Hashimoto's thyroiditis. These data indicate that MHC class II is involved in the tissue-specific development of autoimmune diseases, including T1D and thyroiditis.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Tireoidite Autoimune/imunologia , Animais , Diabetes Mellitus Tipo 1/genética , Mutação , Ratos , Tireoidite Autoimune/genética , Tireoidite Autoimune/patologia
5.
Allergy ; 67(10): 1241-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22845063

RESUMO

BACKGROUND: FcεRIß reportedly functions as an amplifier of the FcεRIγ-mediated activation signal using a reconstitution system. However, the amplification mechanisms in human mast cells (MCs) are poorly understood. We previously reported the hyperexpression of FcεRIß of MCs in giant papillae from vernal keratoconjunctivitis patients, compared with that in conjunctivae from nonallergic conjunctivitis patients. Elucidation of the molecular mechanisms of the amplification induced by FcεRIß should provide new targets for novel therapeutic interventions. The aim is to understand in greater details the function of FcεRIß in human MC FcεRI expression and signaling. METHODS: FcεRIß and Lyn expression was reduced using a lentiviral shRNA silencing technique. Localization of Lyn and FcεRIß in cultured MCs was examined by confocal microscopic analysis. Mediators were measured by ELISAs. RESULTS: The diminution of FcεRIß significantly downregulated cell surface FcεRI expression and FcεRI-mediated mediator release/production. The downregulation of FcεRI-mediated degranulation was not only due to the decrease in FcεRI expression. The diminution of FcεRIß inhibited the redistribution of Lyn within the cell membrane following IgE sensitization. The diminution of Lyn in MCs significantly downregulated FcεRI-mediated degranulation. The recombinant cell-penetrating forms of phosphorylated FcεRIß immunoreceptor tyrosine-based activation motif (ITAM) for intracellular delivery disturbed the interaction between Lyn and phosphorylated endogenous FcεRIß ITAM, resulted in inhibiting IgE-dependent histamine release from MCs in vitro and from giant papillae specimens ex vivo. CONCLUSION: The interaction between Lyn and FcεRIß is indispensable for FcεRI-mediated human MC activation, and specific inhibition of the interaction may represent a new therapeutic strategy for the treatment of human allergic diseases.


Assuntos
Mastócitos/imunologia , Receptores de IgE/imunologia , Quinases da Família src/metabolismo , Adulto , Degranulação Celular/imunologia , Células Cultivadas , Regulação para Baixo , Humanos , Receptores de IgE/metabolismo , Transdução de Sinais
6.
Nat Commun ; 9(1): 4922, 2018 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-30467312

RESUMO

A rectenna, standing for a rectifying antenna, is an apparatus which generates d.c. electricity from electric fluctuations. It is expected to realize wireless power transmission as well as energy harvesting from environmental radio waves. To realize such rectification, devices that are made up of internal atomic asymmetry such as an asymmetric junction have been necessary so far. Here we report a material that spontaneously generates electricity by rectifying environmental fluctuations without using atomic asymmetry. The sample is a common superconductor without lowered crystalline symmetry, but, just by putting it in an asymmetric magnetic environment, it turns into a rectifier and starts generating electricity. Superconducting vortex strings only annihilate and nucleate at surfaces, and this allows the bulk electrons to feel surface fluctuations in an asymmetric environment: a vortex rectenna. The rectification and generation can be switched on and off with only a slight change in temperature or external magnetic fields.

7.
J Clin Invest ; 100(8): 2015-21, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9329965

RESUMO

The Long-Evans Tokushima Lean (LETL) rat, characterized by rapid onset of insulin-dependent (type I) diabetes mellitus (IDDM), no sex difference in the incidence of IDDM, autoimmune destruction of pancreatic beta cells, and no significant T cell lymphopenia, is a desirable animal model for human IDDM. We have established a diabetes-prone substrain of the LETL rat, named Komeda Diabetes-Prone (KDP) rat, showing a 100% development of moderate to severe insulitis within 220 d of age. The cumulative frequency of IDDM was 70% at 120 d of age, and reached 82% within 220 d of age. Here, we performed the first genome-wide scan for non-MHC IDDM susceptibility genes in this strain. The analysis of three crosses has led to the revelation of a major IDDM susceptibility gene, termed Iddm/kdp1, on rat chromosome (Chr) 11. Homozygosity for the KDP allele at this locus is shown to be essential for the development of moderate to severe insulitis and the onset of IDDM. Comparative mapping suggests that the homologues of Iddm/ kdp1 are located on human Chr 3 and mouse Chr 16 and would therefore be different from previously reported IDDM susceptibility genes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Ilhotas Pancreáticas/patologia , Pancreatite/genética , Animais , Mapeamento Cromossômico , Cromossomos Humanos Par 3 , Cruzamentos Genéticos , Diabetes Mellitus Tipo 1/etiologia , Suscetibilidade a Doenças , Ligação Genética , Marcadores Genéticos , Genoma , Genótipo , Haplótipos , Homozigoto , Humanos , Camundongos , Ratos , Ratos Endogâmicos , Índice de Gravidade de Doença , Especificidade da Espécie
8.
Phys Rev E ; 93(3): 033125, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27078465

RESUMO

The effect of kinetic helicity (velocity-vorticity correlation) on turbulent momentum transport is investigated. The turbulent kinetic helicity (pseudoscalar) enters the Reynolds stress (mirror-symmetric tensor) expression in the form of a helicity gradient as the coupling coefficient for the mean vorticity and/or the angular velocity (axial vector), which suggests the possibility of mean-flow generation in the presence of inhomogeneous helicity. This inhomogeneous helicity effect, which was previously confirmed at the level of a turbulence- or closure-model simulation, is examined with the aid of direct numerical simulations of rotating turbulence with nonuniform helicity sustained by an external forcing. The numerical simulations show that the spatial distribution of the Reynolds stress is in agreement with the helicity-related term coupled with the angular velocity, and that a large-scale flow is generated in the direction of angular velocity. Such a large-scale flow is not induced in the case of homogeneous turbulent helicity. This result confirms the validity of the inhomogeneous helicity effect in large-scale flow generation and suggests that a vortex dynamo is possible even in incompressible turbulence where there is no baroclinicity effect.

9.
Eye (Lond) ; 30(6): 857-64, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27055679

RESUMO

PurposeTo investigate the effect of 3% diquafosol sodium ophthalmic solution (DQS) on aqueous tear volume increase in dry-eye patients with Sjögren's syndrome (SS).MethodsIn this pilot study, 17 dry-eye patients with SS (1 male and 16 females; mean age: 66.4 years) were enrolled and underwent topical instillation of two ophthalmic solutions, artificial tears (AT) in one eye and DQS in the fellow eye, in a masked manner. The central lower tear meniscus radius (TMR) curvature was measured before and at 15 min after instillation by video-meniscometry. Simultaneously, all patients self-evaluated their symptoms of wetness and stinging using a visual analog scale (VAS, in millimeters).ResultsTopical instillation of DQS significantly increased the TMR at 15 min (mean: 0.21±0.08 (SD) mm) compared with at baseline (mean: 0.16±0.07 mm) (P<0.001, paired t-test), whereas AT had no effect at baseline (mean: 0.18±0.09 mm) or at 15 min (mean: 0.18±0.09 mm). The visual VAS score of wetness at 15-min post-instillation increased in both groups compared with at baseline. In the DQS-treated eyes, the post-instillation change in TMR from baseline was not correlated with the baseline value of the Schirmer test, corneal staining score, or conjunctival staining score.ConclusionsTopical instillation of DQS increased aqueous tear volume on the ocular surface of dry-eye patients with SS, with its action being independent of lacrimal gland function.


Assuntos
Soluções Oftálmicas/administração & dosagem , Polifosfatos/administração & dosagem , Agonistas do Receptor Purinérgico P2Y/administração & dosagem , Síndrome de Sjogren/tratamento farmacológico , Lágrimas/metabolismo , Nucleotídeos de Uracila/administração & dosagem , Administração Tópica , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Síndrome de Sjogren/metabolismo
10.
Diabetes ; 50(4): 891-4, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11289058

RESUMO

The allele frequencies for a Pro12-->Ala substitution in peroxisome proliferator-activated receptor-gamma differ among ethnic groups, and its relationship with diabetes and associated diseases is controversial. The prevalence of this polymorphism and its effects on clinical characteristics have now been evaluated with a large number of Japanese individuals with type 2 diabetes (n = 2,201) and normal control subjects (n = 1,212) recruited by 10 institutions located in seven different cities in Japan. The allele frequency for the Ala12 variant was significantly lower in the type 2 diabetic group than in the control group (2.39 vs. 4.13%, P = 0.000054). However, compared with subjects without the Ala12 variant, the diabetic subjects with this variant exhibited a significantly higher serum concentration of total cholesterol (P = 0.001), manifested a reduced capacity for insulin secretion as evaluated by homeostasis model assessment (P = 0.007), and tended to possess a higher level of HbA1c. These data suggest that the Ala12 variant is associated with a reduced risk for the development of diabetes in the general population, but that it may be also a risk factor for insulin deficiency and disease severity in individuals with type 2 diabetes.


Assuntos
Substituição de Aminoácidos , Diabetes Mellitus/genética , Predisposição Genética para Doença , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Adulto , Idoso , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Insulina/metabolismo , Secreção de Insulina , Masculino , Pessoa de Meia-Idade
11.
Prog Retin Eye Res ; 20(5): 639-73, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11470454

RESUMO

An appreciation of the biological characteristics of the human ocular surface epithelium affords us a great insight into the physiology of the human ocular surface in health and disease. Here, we review five important aspects of the human ocular surface epithelium. First, we recognize the discovery of corneal epithelial stem cells, and note how the palisades of Vogt have been suggested as a clinical marker of their presence. Second, we introduce the concept of the gene expression profile of the ocular surface epithelium as arrived at using a new strategy for the systematic analysis of active genes. We also provide a summary of several genes abundantly or uniquely expressed in the human corneal epithelium, namely clusterin, keratin 3, keratin 12, aldehyde dehydrogenase 3 (ALDH3), troponin-I fast-twitch isoform, ssig-h3, cathepsin L2 (cathepsin V), uroplakin Ib, and Ca(2+)-activated chloride channel. Genes related to limbal and conjunctival epithelia are also described. Third, we touch upon the genetic abnormalities thought to be involved with epithelial dysfunction in Meesmann's dystrophy, gelatinous drop-like corneal dystrophy, and the ssig-h3-mutated corneal dystrophies. Fourth, we provide an update regarding the current state of knowledge of the role of cytokines, growth factors and apoptosis in relation to ocular surface homeostasis and tissue reconstruction; the main factors being epidermal growth factor (EGF), keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), transforming growth factor-ss (TGF-ss), and some inflammatory cytokines. Fifth, corneal epithelial barrier function and dysfunction as measured by fluorophotometry is remarked upon, with an explanation of the FL-500 fluorophotometer and its ability to detect corneal epithelial dysfunction at a subclinical level. The research described in this review has undoubtedly generated a complete understanding of corneal epithelial pathophysiology-an understanding that, directly or indirectly, has helped advance the development of new therapeutic modalities for ocular surface reconstruction.


Assuntos
Epitélio Corneano , Apoptose , Distrofias Hereditárias da Córnea/fisiopatologia , Citocinas/fisiologia , Epitélio Corneano/citologia , Epitélio Corneano/fisiologia , Proteínas do Olho/biossíntese , Proteínas do Olho/genética , Expressão Gênica/fisiologia , Substâncias de Crescimento/fisiologia , Humanos , Linhagem , Células-Tronco/fisiologia
12.
Eye (Lond) ; 29(9): 1204-12, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26160526

RESUMO

PURPOSE: To investigate the long-term results of 3% diquafosol ophthalmic solution as an alternative therapy to existing ophthalmic solutions, including topical immunosuppression, for the treatment of dry eye in patients with Sjögren's syndrome. METHODS: This study involved 14 female dry-eye patients (mean age: 62.4 years) with Sjögren's syndrome who insufficiently responded to their current therapy. In all patients, 3% diquafosol ophthalmic solution was administered six times daily for 12 months in substitution for artificial tears and sodium hyaluronate ophthalmic solution. Their use of corticosteroid eye drops remained unchanged from that prior to the treatment with diquafosol sodium. The subjective symptoms assessed, and ocular signs including tear meniscus radius and the tear film breakup time, and ocular-surface epithelial damage score were examined at 1, 2, 3, 4, 5, 6, 9, and 12 months after initiating treatment. RESULTS: Among the subjective symptoms, significant improvement was obtained in dryness at 2 months post treatment, in eye fatigue at 1, 2, 3, 4, and 12 months post treatment, and in pain at 1, 2, 6, and 12 months post treatment. Difficulty in opening the eye, foreign body sensation, and redness were also significantly ameliorated at various time-points. The tear meniscus radius and the tear film breakup time were significantly improved throughout the observation period, and the corneal epithelial staining scores were significantly decreased at 3 months post treatment. CONCLUSIONS: In dry-eye patients with Sjögren's syndrome, treatment with 3% diquafosol ophthalmic solution improved both symptoms and signs, and that effectiveness was maintained for 12 months.


Assuntos
Síndromes do Olho Seco/tratamento farmacológico , Lubrificantes Oftálmicos/uso terapêutico , Soluções Oftálmicas/uso terapêutico , Polifosfatos/uso terapêutico , Síndrome de Sjogren/complicações , Nucleotídeos de Uracila/uso terapêutico , Idoso , Esquema de Medicação , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Agonistas do Receptor Purinérgico P2Y , Lágrimas/metabolismo
13.
FEBS Lett ; 448(2-3): 254-6, 1999 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-10218486

RESUMO

A cDNA clone encoding angiopoietin-3 protein (Ang3), a novel member of the angiopoietin family, was identified. Ang3 cDNA was cloned from a human aorta cDNA library. Ang3 is a 503 amino acid protein having 45.1% and 44.7% identity with human angiopoietin-1 and human angiopoietin-2, respectively. Ang3 mRNA is expressed in lung and cultured human umbilical vein endothelial cells (HUVECs). Ang3 mRNA expression in HUVECs was slightly decreased by vascular endothelial cell growth factor treatment, suggesting that the regulation of Ang3 mRNA expression is different from that of Ang2.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular , Proteínas/metabolismo , Sequência de Aminoácidos , Proteína 1 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas , Northern Blotting , Mapeamento Cromossômico , Cromossomos Humanos Par 20 , Clonagem Molecular , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Família Multigênica , Mapeamento Físico do Cromossomo , Homologia de Sequência de Aminoácidos , Sitios de Sequências Rotuladas , Distribuição Tecidual
14.
Invest Ophthalmol Vis Sci ; 35(8): 3289-94, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8045718

RESUMO

PURPOSE: To study spatial distribution of TGF-beta isoforms (TGF-beta 1, -beta 2, and -beta 3) in the human cornea and to elucidate their biologic roles in corneal maintenance. METHODS: Frozen sections obtained from eight human autopsy eyes were placed on gelatin-coated slides. After blocking of nonspecific binding sites, the slides were incubated with rabbit polyclonal antibody to the latency-associated peptide (LAP) region of human TGF-beta 1, TGF-beta 2, and TGF-beta 3 precursors, followed by the incubation with biotinylated swine anti-rabbit IgG. Subsequently, a streptavidin-labeled alkaline phosphatase technique was used. RESULTS: In the corneal region, beta 1-LAP antibody did not stain either epithelium or stroma, beta 2-LAP antibody stained all epithelial cell layers and the corneal stroma, and beta 3-LAP antibody stained the subepithelial region alone. The staining pattern in the limbal region was almost the same as in the corneal region, except in the limbal stroma, which was stained with beta 1-LAP antibody in three of eight samples. In the trabecular meshwork, all samples showed clear staining with beta 2-LAP antibody, whereas beta 1-LAP and beta 2-LAP antibody stained faintly in five of eight and four of eight samples, respectively. CONCLUSION: beta 2-LAP was found in the corneal epithelium and stroma and beta 3-LAP in the subepithelial region, suggesting that TGF-beta 2 and TGF-beta 3 may play essential roles in normal corneal epithelial maintenance in vivo.


Assuntos
Proteínas de Transporte/análise , Córnea/química , Peptídeos e Proteínas de Sinalização Intracelular , Fator de Crescimento Transformador beta/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Técnicas Imunoenzimáticas , Proteínas de Ligação a TGF-beta Latente , Limbo da Córnea/química , Masculino , Pessoa de Meia-Idade , Peptídeos/análise , Malha Trabecular/química
15.
Invest Ophthalmol Vis Sci ; 41(12): 3748-53, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11053272

RESUMO

PURPOSE: To elucidate the effect of the cotton thread test (CT-T) and Schirmer test (S-T) on the tear reservoir by evaluating the radius of tear meniscus curvature. METHODS: The radii (R) of the central lower tear menisci were measured by a newly developed video meniscometer in 11 eyes of 11 normal volunteers (6 men, 5 women; mean age, 27.7 +/- 3.6 years [SD]) and 9 eyes of 9 patients with tear deficiency and severe dry eye in whom the puncta had been therapeutically occluded (9 women; mean age, 50.6 +/- 10.4 years). In this dry eye group, the absence of reflex tearing, coupled with the absence of lacrimal drainage due to punctal occlusion allowed more precise observation of the removal of tears from the meniscus. A 1-minute CT-T was performed, followed after an interval of 10 minutes by a 1-minute S-T. Tear meniscus curvature was documented before (R:(0)) and during the tests at 30 seconds (R(30)) and 60 seconds (R:(60)). RESULTS: In the normal group, respective R values (CT-T; S-T; mean +/- SD mm) were R(0) (0.26 +/- 0.11; 0.26 +/- 0. 07), R(30) (0.27 +/- 0.16; 0.20 +/- 0.13), and R(60) (0.29 +/- 0.15; 0.23 +/- 0.21); and in the dry eye group, respective R: values (CT-T; S-T) were R(0) (0.59 +/- 0.23; 0.51 +/- 0.19), R(30) (0.52 +/- 0.25; 0.22 +/- 0.09), and R(60) (0.51 +/- 0.19; 0.21 +/- 0.08). It was demonstrated in the dry eye group that R was diminished more by the S-T than by the CT-T in the time course of the measurement (P = 0.01). In the dry eye group alteration of R occurred within the first 30 seconds, and in this group significant correlation was found between R(0) and the S-T result (r = 0.67; P = 0.05), and between R(60)- R(0) and the S-T result (r = -0.81; P = 0.01). Also, there was a significant correlation between R(60)- R(0) and the S-T result in the normal group (r = 0.71; P = 0.02). There were no significant correlations between R(0) or R(60)- R(0) and the CT-T results in either group. CONCLUSIONS: These studies afford some insight into the dynamics of the Schirmer test, suggesting that wetting is influenced by the negative hydrostatic pressure within the tear meniscus. With the protocol used, no conclusion could be drawn about the relation between meniscus radius and wetting of the cotton thread.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/metabolismo , Aparelho Lacrimal/metabolismo , Lágrimas/metabolismo , Adulto , Idoso , Síndromes do Olho Seco/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lágrimas/química
16.
Environ Health Perspect ; 87: 57-62, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2269241

RESUMO

Matched case-control studies have recently been used to evaluate the effectiveness of cancer screening. They enable us to estimate the odds ratios of dying of cancer or of getting invasive cancer. The study compares people with various patterns of screening history with those who were not screened. Criteria for eligible cases, controls, and screening histories that are compared as exposures are discussed. The results from a case-control study for evaluating screening for cervical cancer are shown as an example. Also, a study design of a case-control study for evaluating lung cancer screening in Japan is discussed, along with biases and applications of case-control studies in evaluating cancer screening.


Assuntos
Estudos de Casos e Controles , Programas de Rastreamento/métodos , Neoplasias/epidemiologia , Adulto , Idoso , Feminino , Humanos , Japão/epidemiologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/prevenção & controle , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Neoplasias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle
17.
Arch Ophthalmol ; 117(6): 723-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10369581

RESUMO

OBJECTIVE: To study meibomian gland function in dry eyes using meibometry. METHODS: Forty-two patients with clinically diagnosed dry eye that was reclassified as meibomian gland dysfunction (MGD [n = 12]), aqueous-tear deficiency (AD [n = 10]), MGD combined with AD (n = 2), "incomplete" dry eye (n = 12), and non-dry eye (6 eyes) were compared with 41 healthy control subjects. The following 2 techniques of meibometry were applied: direct meibometry (DM) measuring lipid imprints using the Meibometer, and integrated meibometry (IM) using image-scanning and computer densitometry. Tear film lipid layer thickness was assessed using interference microscopy. RESULTS: Imprints were homogeneous for all subjects except those with MGD. Mean+/-SE readings on results of DM were 127.24+/-24.4 for MGD, 306.4+/-9.2 for AD, 248.6+/-13.2 for incomplete dry eye, and 268.5+/-6.3 for controls, showing lower values in the MGD group relative to all others (P<.001). Results of IM gave similar results (P<.001, P =.01, and P<.001, respectively). Lipid layers appeared lower for the MGD group than others. CONCLUSIONS: Compared with controls, lid lipid levels are reduced in patients with MGD, and increased in women with AD. Lipid layer thickness is increased in women with AD compared with patients with MGD. Both meibometric techniques may be useful for evaluating MGD. Although DM requires special equipment (the Meibometer), it provides a record of immediate diagnostic value. Although IM is less effective than DM, it offers visual documentation of the lipid imprint, which may itself be of diagnostic value, and uses equipment available in many laboratories.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/fisiopatologia , Glândulas Tarsais/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Síndromes do Olho Seco/metabolismo , Pálpebras/metabolismo , Feminino , Humanos , Metabolismo dos Lipídeos , Masculino , Glândulas Tarsais/metabolismo , Pessoa de Meia-Idade , Lágrimas/metabolismo
18.
Fertil Steril ; 72(1): 15-20, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10428142

RESUMO

OBJECTIVE: To evaluate disturbances of the hypothalamic-pituitary-adrenal axis in women with polycystic ovary syndrome (PCOS). DESIGN: Retrospective cohort study. SETTING: Yokohama City University, Yokohama, Japan. PATIENT(S): Sixty women with PCOS and 19 women with normal menstruation. INTERVENTION(S): Administration of human corticotropin-releasing hormone (hCRH), dexamethasone suppression testing, and stimulation of ovulation with clomiphene citrate. MAIN OUTCOME MEASURE(S): Plasma cortisol and ACTH levels, plasma androstenedione and DHEAS levels, and ovulation rates. RESULT(S): In women with PCOS, plasma ACTH and cortisol levels were significantly higher and the plasma ACTH level after the administration of hCRH was higher than in controls. Based on the response to hCRH, patients with PCOS could be classified into three categories: those with a normal response to hCRH (group 1), those with an exaggerated response of ACTH to hCRH (group 2), and those with a high basal level of cortisol and a poor response to hCRH (group 3). In groups 2 and 3, DHEAS levels were significantly higher, suppression of androstenedione by dexamethasone was significantly greater, and ovulation rates with clomiphene citrate were significantly lower than in group 1. CONCLUSION(S): This classification provides insight into the underlying cause of PCOS and thus is useful in selecting appropriate treatment.


Assuntos
Hormônio Liberador da Corticotropina , Síndrome do Ovário Policístico/classificação , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Hormônio Adrenocorticotrópico/sangue , Adulto , Androgênios/sangue , Clomifeno/administração & dosagem , Estudos de Coortes , Dexametasona , Feminino , Gonadotropinas Hipofisárias/sangue , Hirsutismo/complicações , Hirsutismo/epidemiologia , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Obesidade/complicações , Obesidade/epidemiologia , Ovulação/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações
19.
Fertil Steril ; 76(4): 748-52, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11591409

RESUMO

OBJECTIVE: To longitudinally evaluate disturbances of the hypothalamic-pituitary-adrenal (HPA) axis in women with secondary progestin-negative hypothalamic amenorrhea. DESIGN: Retrospective cohort study. SETTING: Yokohama City University, Yokohama, Japan. PATIENT(S): Twenty-four women with progestin-negative hypothalamic amenorrhea. INTERVENTION(S): Administration of human corticotropin-releasing hormone (hCRH) and treatment with a combination of estrogen and progesterone. MAIN OUTCOME MEASURE(S): Plasma cortisol and ACTH concentrations and period required for recovery from amenorrhea. RESULT(S): Plasma ACTH concentrations 30 and 60 minutes after injection of hCRH and the percent maximum increment (%Cmax) of ACTH were significantly lower in the amenorrheic patients compared with the control group patients. The basal cortisol was significantly higher, and the %Cmax of cortisol was significantly lower. In the 16 patients who recovered from amenorrhea, there was a significant positive correlation (Y = 1.93X-10.8, r = 0.629) between the basal cortisol concentrations (X) and the period for recovery (Y). The serum E2 gradually increased before recovery, and this E2 increase was preceded by changes in the plasma cortisol concentration and the %Cmax values of cortisol and ACTH. CONCLUSION(S): The CRH test might be useful for evaluating the roles of stress and for estimating the period required for recovery in hypothalamic amenorrhea.


Assuntos
Amenorreia/etiologia , Amenorreia/fisiopatologia , Doenças Hipotalâmicas/complicações , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Progestinas/sangue , Hormônio Adrenocorticotrópico/sangue , Adulto , Amenorreia/tratamento farmacológico , Hormônio Liberador da Corticotropina/farmacologia , Congêneres do Estradiol/uso terapêutico , Feminino , Humanos , Hidrocortisona/sangue , Estudos Longitudinais , Mestranol/uso terapêutico , Noretindrona/uso terapêutico , Congêneres da Progesterona/uso terapêutico , Valores de Referência , Fatores de Tempo
20.
Am J Ophthalmol ; 122(6): 818-24, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8956636

RESUMO

PURPOSE: To observe and classify tear film lipid layer interference patterns in normal volunteers and dry eye patients and to investigate the relation between the lipid layer interference patterns in the dry eyes and the results of other dry eye examinations. METHODS: Precorneal tear lipid layer interference patterns were observed at the central cornea in 25 eyes of 13 normal controls and 85 eyes of 48 dry eye patients. Observed patterns were classified in masked fashion by five physicians into five grades: grade 1, somewhat gray color, uniform distribution; grade 2, somewhat gray color, nonuniform distribution; grade 3, a few colors, nonuniform distribution; grade 4, many colors, nonuniform distribution; and grade 5, corneal surface partially exposed. Other methods of dry eye examination were also performed, including the cotton thread test, the Schirmer I test and modified Schirmer I test, measurement of tear film breakup time, scoring of corneal fluorescein staining density (grades 0 to 3) and area (grades 0 to 3), and rose bengal staining (grades 0 to 9). RESULTS: In 92 (84%) of 110 eyes, four or more of the five physicians agreed in their grade classifications. Among the 92 eyes, normal control eyes were classified into grades 1 and 2 (10 and 12 eyes, respectively) and dry eyes were classified into grades 2, 3, 4, and 5 (22, 26, 10, and 12 eyes, respectively). There was a significant correlation between the grading and the results of other dry eye examination modalities, including fluorescein staining, rose bengal staining, and tear film breakup time. CONCLUSIONS: Tear lipid layer interference patterns are highly correlated with dry eye severity.


Assuntos
Síndromes do Olho Seco/diagnóstico , Metabolismo dos Lipídeos , Lágrimas/metabolismo , Adolescente , Adulto , Idoso , Criança , Córnea/patologia , Síndromes do Olho Seco/classificação , Síndromes do Olho Seco/metabolismo , Epitélio/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Índice de Gravidade de Doença
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