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2.
Exp Cell Res ; 319(8): 1220-8, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23500413

RESUMO

Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Proteínas de Ligação a DNA/fisiologia , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Análise em Microsséries , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/fisiologia , Proteínas de Ligação a RNA , Nicho de Células-Tronco/genética , Transfecção , Microambiente Tumoral/genética
3.
Clin Exp Allergy ; 43(4): 413-24, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23517037

RESUMO

BACKGROUND: The thromboxane A2 receptor (TBXA2R) gene is associated with asthma, but no functional genetic variations are known to associate with the disease or its related phenotypes. OBJECTIVE: To investigate the association of TBXA2R polymorphisms with asthma susceptibility and related phenotypes and to identify functionally relevant polymorphisms. METHODS: We performed comprehensive sequencing of the TBXA2R gene in 48 Japanese control subjects and found a set of variants (SNP1 G>T rs2238634, SNP2 T>G rs2238633, SNP3 C>T rs2238632 and SNP4 G>A rs2238631) in intron 1 in linkage disequilibrium with c.795 T>C rs1131882, which was previously reported to be associated with asthma and related phenotypes. To investigate the effect of four common haplotypes (H1, H2, H3 and H4) on transcriptional activity, we performed a luciferase assay in primary bronchial smooth muscle cells (BSMCs) and human airway epithelial cells (BEAS-2B). We also studied the haplotype association with lung function, TBXA2R mRNA levels, and eosinophil fraction/count in peripheral blood in childhood-onset asthma patients and/or controls. RESULTS: H2 and H4, containing minor alleles of SNP2 and SNP3, had significantly higher transcriptional activities than H1 consisting of major alleles (P < 0.001 in BSMCs and BEAS-2B). Homozygotes for redefined haplotype h2 corresponding to minor alleles of SNP2 and SNP3 were associated with lower lung function in childhood-onset asthma patients compared to other zygotes (baseline Forced expiratory volume in one second (FEV1)/ Forced vital capacity (FVC) and Forced expiratory flow between 25% and 75% of the FVC (%FEF(25-75%)): P = 0.00201 and 0.0128, respectively, and post-bronchodilator FEV1/FVC and %FEF(25-75%): P = 0.00224 and 0.0393 respectively). Haplotype h2 was also associated with higher mRNA levels in control peripheral blood cells and higher blood eosinophil fractions and counts in female controls. CONCLUSIONS AND CLINICAL RELEVANCE: Genetic variants were identified in the TBXA2R gene that influenced transcriptional activity and were associated with asthma-related phenotypes. Thromboxane pathways may therefore play important roles in airway inflammation and remodelling in asthma patients.


Assuntos
Asma/genética , Asma/fisiopatologia , Receptores de Tromboxano A2 e Prostaglandina H2/genética , Adolescente , Adulto , Idade de Início , Asma/sangue , Estudos de Casos e Controles , Criança , Eosinófilos , Feminino , Estudos de Associação Genética , Haplótipos , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Íntrons , Contagem de Leucócitos , Desequilíbrio de Ligação , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Receptores de Tromboxano A2 e Prostaglandina H2/metabolismo , Testes de Função Respiratória , Fatores de Transcrição/metabolismo , Adulto Jovem
4.
JAR Life ; 12: 56-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519417

RESUMO

Background: Exercise, education, and social engagement are critical interventions for older adults for a healthy life expectancy and to improve their physical function. Objective: To conduct a combined exercise and education (CEE) program for improved social engagement and physical function of older adults. Design: Based on a short-term program we conducted in our previous study, in this study, the program was conducted for half the number of participants of the earlier study but for a longer duration. Setting: A community of older adults in Ami, Japan, was the setting of the study. Participants: 23 healthy older adults >65 years living in the community were the participants in the study. Interventions: Five 80-minute sessions conducted once in two weeks comprised 60-min exercise instruction and 20-min educational lectures per session on health. We examined the improvement in physical and social engagement before and after participation. Physical function and health-related questionnaire data were collected before and after the program. Results: Data analysis from 15 participants showed improved physical performance but no effect on social engagement. Conclusions: A higher program frequency, rather than program duration, may be vital to improving exercise performance and social engagement and maximizing the effects of high group cohesion in small groups. Further studies are needed to develop more effective interventions to extend healthy life expectancy.

5.
Epidemiol Infect ; 140(6): 1111-21, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21875450

RESUMO

The 7-valent pneumococcal conjugate vaccine (PCV7) is reported to decrease the incidence of community-acquired pneumonia (CAP) in children. To determine the annual incidence of CAP before the introduction of PCV7, we counted the number of children hospitalized with CAP between 2008 and 2009 in Chiba City, Japan. We investigated serotype and multilocus sequence typing (MLST) for Streptococcus pneumoniae isolates in CAP cases. The annual incidence of hospitalized CAP in children aged <5 years was 17.6 episodes/1000 child-years. In 626 episodes, S. pneumoniae was dominant in 14.7% and 0.8% of sputum and blood samples, respectively. The most common serotypes were 6B, 23F and 19F. The coverage rates of PCV7 were 66.7% and 80% in sputum samples and blood samples, respectively. MLST analysis revealed 37 sequence types. Furthermore, 54.1% of the sputum isolates and 40% of the blood isolate were related to international multidrug-resistant clones.


Assuntos
Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/microbiologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/genética , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , Humanos , Incidência , Lactente , Japão/epidemiologia , Filogenia
6.
Allergy ; 66(10): 1287-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21781135

RESUMO

BACKGROUND: Asthma and rhinitis are common co-morbidities everywhere in the world but nation-wide studies assessing rhinitis in asthmatics using questionnaires based on guidelines are not available. OBJECTIVE: To assess the prevalence, classification, and severity of rhinitis using the Allergic Rhinitis and its Impact on Asthma (ARIA) criteria in Japanese patients with diagnosed and treated asthma. METHODS: The study was performed from March to August 2009. Patients in physicians' waiting rooms, or physicians themselves, filled out questionnaires on rhinitis and asthma based on ARIA and Global Initiative for Asthma (GINA) diagnostic guides. The patients answered questions on the severity of the diseases and a Visual Analog Scale. Their physicians made the diagnosis of rhinitis. RESULTS: In this study, 1910 physicians enrolled 29,518 asthmatics; 15,051 (51.0%) questionnaires were administered by physician, and 26,680 (90.4%) patients were evaluable. Self- and physician-administered questionnaires gave similar results. Rhinitis was diagnosed in 68.5% of patients with self-administered questionnaires and 66.2% with physician-administered questionnaires. In this study, 994 (7.6%) patients with self-administered and 561 (5.2%) patients with physician-administered questionnaires indicated rhinitis symptoms on the questionnaires without a physician's diagnosis of rhinitis. Most patients with the physician's diagnosis of rhinitis had moderate/severe rhinitis. Asthma control was significantly impaired in patients with a physician's diagnosis of rhinitis for all GINA clinical criteria except exacerbations. There were significantly more patients with uncontrolled asthma as defined by GINA in those with a physician's diagnosis of rhinitis (25.4% and 29.7%) by comparison with those without rhinitis (18.0% and 22.8%). CONCLUSION: Rhinitis is common in asthma and impairs asthma control.


Assuntos
Asma/complicações , Rinite/complicações , Rinite/epidemiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Adulto Jovem
7.
J Exp Med ; 156(5): 1486-501, 1982 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-6813419

RESUMO

We studied the genetic restrictions on the interaction between T cells, B cells, and antigen-presenting cells (APC) involved in the H-2-linked Ir gene control of the in vitro secondary antibody response to sperm whale myoglobin (Mb) in mice. The B cells in this study were specific for Mb itself, rather than for a hapten unrelated to the Ir gene control, as in many previous studies. Low responder mice immunized in vivo with Mb bound to an immunogenic carrier, fowl gamma globulin (F gamma G), produced B cells competent to secrete anti-Mb antibodies in vitro if they received F gamma G-specific T cell help. However, (high-responder X low responder) F1 T cells from Mb-immune mice did not help these primed low responder (H-2k or H-2b) B cells in vitro, even in the presence of various numbers of F1 APC that were demonstrated to be component to reconstitute the response of spleen cells depleted by APC. Similar results were obtained with B6 leads to B6D2F1 radiation bone marrow chimeras. Genotypic low responder (H-2b) T cells from these mice helped Mb-primed B6D2F1B cells plus APC, but did not help syngeneic chimeric H-2b B cells, even in the presence of F1 APC. In contrast, we could not detect any Ir restriction on APC function during these in vitro secondary responses. Moreover, in the preceding paper, we found that low responder mice neonatally tolerized to higher responder H-2 had competent Mb-specific helper T cells capable of helping high responder but not low responder B cells and APC. Therefore, although function Mb-specific T cells and B cells both exist in low responder mice, the Ir gene defect is a manifestation of the failure of syngeneic collaboration between these two cell types. This genetic restriction on the interaction between T cells and B cells is consistent with the additional new finding that Lyb-5-negative B cells are a major participant in ths vitro secondary response because it is this Lyb-5-negative subpopulation of B cells that have recently been shown to require genetically restricted help. The Ir gene defect behaves operationally as a failure of low responder B cells to receive help from any source of Mb-specific T cells either high responder, low responder, or F1. The possible additional role of T cell-APC interactions, either during primary immunization in vivo or in the secondary culture is discussed.


Assuntos
Linfócitos B/imunologia , Genes MHC da Classe II , Cooperação Linfocítica , Mioglobina/imunologia , Linfócitos T/imunologia , Animais , Formação de Anticorpos , Antígenos Ly/análise , Memória Imunológica , Camundongos
8.
J Exp Med ; 156(3): 791-809, 1982 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6213732

RESUMO

We sought to examine the role of immune response (Ir) genes in helper T cells. To eliminate allogeneic effects, we used neonatally tolerized mice. The results bear not only on the mechanism of Ir genes, but also on the development of the T cell repertoire. B 10.BR (H-2(k)) or C57BL/10 (H-2(b)) mice, which were low responders to myoglobin (Mb), were neonatally tolerized to high responder H-2(d) alloantigens, and B10.D2 mice, which were high responders to Mb, were neonatally tolerized to low responder H-2(k) or H-2(b) alloantigens. Spleen cells from these tolerized mice did not show any reactivity in mixed-lymphocyte reaction or cell-mediated lympholysis against alloantigens used in tolerization. Mb-immune F(1) B cells were helped comparably by Mb-immune tolerized low or high responder T cells. Thus, low responder T cells functioned equivalently to high responder T cells. The failure of nonimmune T cells from tolerized low responder mice to help F(1) B cells and antigen-presenting cells (APC) indicated that collaboration between B10.BR or C57BL/10 T cells and F(1) B cells was not caused by a positive allogeneic effect. Spleen cells from tolerized mice were contaminated with 2-4 percent chimeric F(1) cells, as judged by fluorescence-activated cell sorter analysis, and no F(1) alloantigens were detectable in the thymus. However, removal of chimeric F(1) T cells from the tolerized cell population by treatment with anti-H-2 and complement did not change the helper activity of tolerized low responder T cells. These data indicated that helper activity in the T cell population from low responder mice was not due to F(1) cells. Also, the level of contamination was not sufficient to quantitatively account for the help. In examining the genetic restriction of these tolerized T cells, we found that T cells from tolerized low responder B10.BR or C57BL/10 mice helped F(1) or high responder B10.D2 B cells and APC but not syngeneic B10.BR or C57BL/10 B cells and APC, which were immunized with Mb-coupled fowl gamma globulin instead of Mb to prime low responder B cells with Mb. On the other hand, high responder B 10.D2 tolerized T cells helped syngeneic B 10.D2 B cells but not allogeneic low responder B10.BR B cells. These data indicated that clones of helper T cells specific for Mb exist in low responder mice, and these are not phenotypically different from those in high responder mice, in that both help high responder and F(1) but not low responder B cells and APC. These data are discussed in terms of the mechanism for Ir gene control, and the mechanism of T cell repertoire development- whether intra- or extrathymically-in neonatally tolerized mice.


Assuntos
Linfócitos B/imunologia , Genes MHC da Classe II , Antígenos H-2/imunologia , Mioglobina/imunologia , Linfócitos T/imunologia , Animais , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Antígenos H-2/genética , Tolerância Imunológica , Isoantígenos/imunologia , Teste de Cultura Mista de Linfócitos , Camundongos , Camundongos Endogâmicos , Linfócitos T Reguladores/imunologia
9.
J Exp Med ; 160(3): 659-78, 1984 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6432932

RESUMO

A rabbit antiidiotypic antiserum raised against an A.SW IgG1K monoclonal anti-sperm whale myoglobin (Mb) antibody, HAL19, and extensively absorbed with normal mouse immunoglobulin and MOPC 21 (IgG1K), was found to detect a common or major anti-Mb idiotype expressed by some but not all anti-Mb monoclonal antibodies, regardless of immunoglobulin G (IgG) subclass, and by 40-50% of the anti-Mb antibodies in immune serum from five high responder strains of mice representing five different Igh allotypes. It did not inhibit antibodies to three unrelated protein antigens. The fraction of antibodies expressing this idiotype, denoted IdHAL19, was regulated by H-2-linked genes that correlated exactly in four independent haplotypes and an F1 with the known Mb immune response (Ir) genes and may be identical to these. Whereas less than 50% of antibodies from high responder mice were inhibitable by anti-IdHAL19, greater than 80% of antibodies from low responder mice, tested at comparable final antibody concentration, were inhibitable. This result was true for both low responder haplotypes, H-2b (B10) and H-2k (B10.BR). The idiotype was found to be present on antibodies that bound to native Mb but not fragments 1-55 or 132-153 of Mb or a denatured form, S-methyl Mb. This specificity for native Mb paralleled that of the monoclonal idiotype HAL19 itself. Therefore, the production of antibodies specific for native in contrast to denatured Mb was studied in H-2-congenic high and low responder strains. Strikingly, low responders produced antibodies that reacted almost exclusively with the native conformation, whereas a larger proportion of antibodies from high responder mice also reacted with the denatured form, S-methyl Mb. Bypassing of the Ir gene defect by immunization with Mb attached to a carrier, F gamma G, resulted in low responder antisera resembling higher responder sera in both idiotype expression and conformational specificity. The simplest explanation of these results is that H-2-linked Ir genes control antibody fine specificity, which is reflected in the idiotypes of the variable regions expressed. We suggest that low responder mice produce a more limited repertoire of antibodies consisting primarily of IdHAL19-positive antibodies specific for the native conformation of Mb. High responder mice produce a greater diversity of antibodies to Mb, so that the IdHAL19-positive, conformation-specific population represents a smaller proportion of the total. Similarly, the use of carrier-specific helper T cells in low responder mice results in a greater diversity of antibodies, which dilutes out the IdHAL19 subset.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Anticorpos Anti-Idiotípicos/genética , Genes MHC da Classe II , Antígenos H-2/genética , Idiótipos de Imunoglobulinas/genética , Mioglobina/imunologia , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Sítios de Ligação de Anticorpos , Ligação Competitiva , Proteínas de Transporte/fisiologia , Ligação Genética , Alótipos de Imunoglobulina/genética , Alótipos de Imunoglobulina/fisiologia , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Coelhos
10.
Osteoarthritis Cartilage ; 17(4): 529-38, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18922704

RESUMO

OBJECTIVE: The effect of the prostaglandin E2 (PGE2) signal through prostaglandin E receptor 2 (EP2) receptors on the repair of injured articular cartilage was investigated using a selective agonist for EP2. METHODS: Chondral and osteochondral defects were prepared on the rabbit femoral concave in both knee joints, and gelatin containing polylactic-co-glycolic acid microspheres conjugated with or without the EP2 agonist was placed nearby. Animals were sacrificed at 4 or 12 weeks post-operation, and regenerated cartilage tissues and subchondral structure remodeling were evaluated by histological scoring. The quality of regenerated tissues was also evaluated by the immunohistochemical staining of EP2, type II collagen, and proliferating cell nuclear antigen (PCNA). As an evaluation of side effects, the inflammatory reaction of the synovial membrane was analyzed based on histology and the mRNA expression of matrix metalloproteinase3 (MMP3), tissue inhibitor of metalloproteinase 3 (TIMP3), and interleukin-1 beta (IL-1 beta). Also, the activity of MMP3 and the amount of tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein in joint fluid were measured. RESULTS: In both models, the EP2 agonist enhanced the regeneration of the type II collagen-positive tissues containing EP2- and PCNA-positive chondrocytes, and the histological scale of regenerated tissue and subchondral bone was better than that of on the control side, particularly at 12 weeks post-operation. No inflammatory reaction in the synovial membrane was observed, and no induction of pro-inflammatory cytokines was found in joint fluid. CONCLUSION: Selective stimulation of the PGE2 signal through EP2 receptors by a specific agonist promoted regeneration of cartilage tissues with a physiological osteochondral boundary, suggesting the potential usefulness of this small molecule for the treatment of injured articular cartilages.


Assuntos
Cartilagem Articular/lesões , Dinoprostona/fisiologia , Receptores de Prostaglandina E/fisiologia , Regeneração/fisiologia , Animais , Proteína C-Reativa/metabolismo , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Cartilagem Articular/fisiologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Metaloproteinase 3 da Matriz/metabolismo , Coelhos , Receptores de Prostaglandina E/agonistas , Receptores de Prostaglandina E Subtipo EP2 , Regeneração/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Líquido Sinovial/metabolismo , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia , Fator de Necrose Tumoral alfa/metabolismo
11.
Plant Biol (Stuttg) ; 11 Suppl 1: 70-5, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19778370

RESUMO

Surface ozone pollution may cause reductions in rice (Oryza sativa L.) yield. Ozone sensitivity in rice cultivars is often evaluated based on visible leaf injury at an early growth stage. However, it is not clear whether reduction in grain yield is related to visible injury. Therefore, visible damage and grain yield reduction were examined in Japanese and Asian rice cultivars exposed to ozone. In experiment 1, 3-week-old rice seedlings were exposed to ozone (min.: 20 nl.l(-1), max.:120 nl.l(-1)) for 12 h in open-top chambers (OTCs). Visible leaf injury was quantified according to a leaf bronzing score. In experiment 2, rice plants were exposed to ozone in OTCs throughout the cropping season until grain harvest. Daily mean ozone concentrations were maintained at 2, 23, 28, 42, and 57 nl.l(-1) with a regular diurnal pattern of exposure. After harvest, grain yield was determined. Based on visible injury to the uppermost fully expanded leaf, the indica cultivar 'Kasalath' was most tolerant, and the japonica cultivar 'Kirara 397' was most sensitive to ozone. However, grain yields for both 'Kasalath' and 'Kirara 397' were significantly decreased after ozone exposure. The indica cultivar 'Jothi' suffered severe injury after ozone exposure but had no reduction in grain yield. Therefore, ozone sensitivity of rice cultivars evaluated by visible injury did not coincide with that evaluated by the reductions in grain yield. These results suggest that mechanisms that induce acute leaf injury do not relate to chronic ozone toxicity that reduces yield.


Assuntos
Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Ozônio/toxicidade , Oxidantes Fotoquímicos/toxicidade
12.
Acta Radiol ; 50(9): 1027-34, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19863413

RESUMO

BACKGROUND: Susceptibility-weighted imaging (SWI) is utilized in magnetic resonance (MR) venography and other applications, but can include artifacts caused by the phase-masking process. PURPOSE: To demonstrate risks of filter processes used in making phase masks for SWI, and to propose a simple method for reducing artifacts. MATERIAL AND METHODS: Phase linearity related to echo time (TE) was evaluated for the original phase and high-pass-filtered phase using a CuSO(4)-doped water phantom. Effect of filter size of the Hanning window and background homogeneity were also evaluated in a phantom study. Use of a phase mask generated by data with differing magnitudes of TE was attempted in a human study. Shorter TE was used for making the phase mask, and the number of multiplications was increased. As short and long TEs were necessary simultaneously for phase mask and T2* contrast, a dual-echo technique was used. RESULTS: Linearity of TE and phase value collapsed, and an unexpected negative phase appeared in the high-pass-filtered phase. Using a short-TE phase mask, phase-aliasing artifacts were reduced and visibility of deep veins was equivalent to that under conventional methods with an increased number of multiplications. CONCLUSION: Use of a short-echo phase mask in SWI is useful for reducing artifacts.


Assuntos
Artefatos , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Humanos , Imagens de Fantasmas
13.
Nat Commun ; 10(1): 2308, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31127111

RESUMO

Atomic-resolution electron microscopes utilize high-power magnetic lenses to produce magnified images of the atomic details of matter. Doing so involves placing samples inside the magnetic objective lens, where magnetic fields of up to a few tesla are always exerted. This can largely alter, or even destroy, the magnetic and physical structures of interest. Here, we describe a newly developed magnetic objective lens system that realizes a magnetic field free environment at the sample position. Combined with a higher-order aberration corrector, we achieve direct, atom-resolved imaging with sub-Å spatial resolution with a residual magnetic field of less than 0.2 mT at the sample position. This capability enables direct atom-resolved imaging of magnetic materials such as silicon steels. Removing the need to subject samples to high magnetic field environments enables a new stage in atomic resolution electron microscopy that realizes direct, atomic-level observation of samples without unwanted high magnetic field effects.

14.
J Neonatal Perinatal Med ; 11(4): 387-392, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30149477

RESUMO

BACKGROUND: We had reported on the left ventricular end-diastolic dimension (LVDd) in normal children from the premature/neonatal period to the adolescence period by using two-dimensional echocardiography, and formulated equations to evaluate normal LVDd values by using body height as an index. There was an inflection point at around birth that seemed relevant to the fetal and neonatal periods for the relation of LVDd and body height. METHODS: We aimed to reveal the true inflection point and its meaning by using change point regression analysis. The study group consisted of 421 neonates and infants. The ages at examination ranged from 24 weeks' gestation to 1 year after birth. The subjects' body heights at examination were between 31 and 75 cm. RESULTS: The analysis showed no definite inflection point in height, and a flat bottom was observed between body heights of 48 and 55 cm. The inflection range seemed to mean the duration of the neonatal period, which connects the fetal and infantile periods. CONCLUSION: The results revealed that neonates reach the infantile period slower than usually imagined, and the end of the neonatal period may be at the age when the body height is around 55 cm- in other words, at 2 months after birth. This manuscript might be the first one to consider the definition of the neonatal period using cardiovascular methods.


Assuntos
Desenvolvimento Infantil/fisiologia , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Volume Cardíaco , Feminino , Idade Gestacional , Ventrículos do Coração/anatomia & histologia , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência , Análise de Regressão
15.
Mol Cell Biol ; 20(17): 6300-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10938106

RESUMO

Regulated cyclin-dependent kinase (CDK) levels and activities are critical for the proper progression of the cell division cycle. p12(DOC-1) is a growth suppressor isolated from normal keratinocytes. We report that p12(DOC-1) associates with CDK2. More specifically, p12(DOC-1) associates with the monomeric nonphosphorylated form of CDK2 (p33CDK2). Ectopic expression of p12(DOC-1) resulted in decreased cellular CDK2 and reduced CDK2-associated kinase activities and was accompanied by a shift in the cell cycle positions of p12(DOC-1) transfectants ( upward arrow G(1) and downward arrow S). The p12(DOC-1)-mediated decrease of CDK2 was prevented if the p12(DOC-1) transfectants were grown in the presence of the proteosome inhibitor clasto-lactacystin beta-lactone, suggesting that p12(DOC-1) may target CDK2 for proteolysis. A CDK2 binding mutant was created and was found to revert p12(DOC-1)-mediated, CDK2-associated cell cycle phenotypes. These data support p12(DOC-1) as a specific CDK2-associated protein that negatively regulates CDK2 activities by sequestering the monomeric pool of CDK2 and/or targets CDK2 for proteolysis, reducing the active pool of CDK2.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/metabolismo , Proteínas Supressoras de Tumor , Western Blotting , Ciclo Celular , Divisão Celular , Linhagem Celular , Cromatografia em Gel , Quinase 2 Dependente de Ciclina , Inibidores de Cisteína Proteinase/farmacologia , Humanos , Queratinócitos/metabolismo , Lactonas/farmacologia , Pulmão/metabolismo , Mutagênese Sítio-Dirigida , Fenótipo , Fosforilação , Ligação Proteica , Biossíntese de Proteínas , Proteínas/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Distribuição Tecidual , Transfecção
16.
J Sports Med Phys Fitness ; 47(3): 356-60, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17641605

RESUMO

AIM: Drug abuse, most notably anabolic-androgenic steroid (AAS) use, in athletes is widespread. As a result, athletes and exercise enthusiasts who abuse these drugs are troubled by the side effects of these illicit drugs, especially AAS. In an attempt to improve this situation, since 1993, we have counseled athletes who abuse drugs and others with questions about AAS via telephone and tabulated the results. METHODS: Counseling sessions took place by telephone every Monday between 19:00-23:00 h. The number of cases was tabulated each year and the specific items discussed during each consultation were categorized by key words. Cases consisted of both drug abusers and athletes who did not abuse drugs and were concerned about the side effects or other various problems surrounding the use of AAS. RESULTS: From 1993 to 1996, there were about 50 cases yearly; thereafter, the number of consultations dropped to about 30 to 40 cases each year. In 2002, consultations with drug abusers accounted for 52.2% of all consultations, compared with 46% of all consultations from 1993 to 2002. CONCLUSION: We have found that abusers of endocrine agents exist in Japan, as well as elsewhere. We hope these results will demonstrate the necessity of employing public institutional counseling systems for athletes who are drug abusers in Japan, similar to the successful system instituted by the Swedish National Service.


Assuntos
Anabolizantes/efeitos adversos , Aconselhamento Diretivo , Prescrições de Medicamentos , Encaminhamento e Consulta , Esportes , Transtornos Relacionados ao Uso de Substâncias/complicações , Telefone , Adulto , Dopagem Esportivo , Humanos , Japão , Masculino , Projetos Piloto , Fatores de Risco , Levantamento de Peso
17.
AJNR Am J Neuroradiol ; 27(3): 584-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16551996

RESUMO

We report the case of an asymptomatic 2-month-old infant with 6-pyruvoyltetrahydropterin synthetase deficiency detected through a neonatal phenylketonuria screening program. MR imaging revealed symmetrical lesions in the central tegmental tract with reduced diffusion, which resolved after treatment. A possible explanation for these lesions is intramyelinic edema resulting from brain insults in utero.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética , Fósforo-Oxigênio Liases/deficiência , Feminino , Humanos , Lactente
18.
Arch Dis Child Fetal Neonatal Ed ; 91(3): F175-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16449256

RESUMO

BACKGROUND: The biochemical features of portosystemic venous shunt with high flow volume are hypergalactosaemia, hyperammonaemia, prolonged blood coagulation time, and raised serum bile acid concentration. The ductus venosus remains open with shunt flow in most neonates for a certain period after birth. However, the effects of blood flow through the ductus venosus on neonatal liver function remain unclear. OBJECTIVE: To elucidate the effect of patency of the ductus venosus on liver function in early neonates. METHODS: Subjects were divided into three groups by gestational age (group I, 29-32 weeks; group II, 33-36 weeks; group III, 37-41 weeks). The shunt flow volume through the ductus venosus was examined serially using ultrasonography, and correlations between flow volume and liver function in the respective groups were calculated during the first week after birth. RESULTS: Group I had a higher flow volume and later functional closure than the other two groups. Plasma ammonia and serum total bile acid concentrations correlated with flow volume in groups I and II, and blood galactose and galactose 1-phosphate concentrations correlated significantly with flow volume in group III. Percentage hepaplastin also correlated significantly with flow volume in all groups, but plasma vitamin K concentration did not in any group. CONCLUSIONS: Patent ductus venosus has a considerable effect on crucial liver functions such as ammonia detoxification, blood coagulation, and regulation of serum total bile acid concentration in early neonates.


Assuntos
Permeabilidade do Canal Arterial/fisiopatologia , Hepatopatias/fisiopatologia , Amônia/sangue , Ácidos e Sais Biliares/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Galactose/sangue , Idade Gestacional , Humanos , Hiperbilirrubinemia Neonatal/etiologia , Hiperbilirrubinemia Neonatal/fisiopatologia , Recém-Nascido , Grau de Desobstrução Vascular
19.
Oncogene ; 20(43): 6196-204, 2001 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-11593428

RESUMO

Large scale gene expression profiling was carried out on laser capture microdissected (LCM) tumor and normal oral epithelial cells and analysed on high-density oligonucleotide microarrays. About 600 genes were found to be oral cancer associated. These oral cancer associated genes include oncogenes, tumor suppressors, transcription factors, xenobiotic enzymes, metastatic proteins, differentiation markers, and genes that have not been implicated in oral cancer. The database created provides a verifiable global profile of gene expression during oral carcinogenesis, revealing the potential role of known genes as well as genes that have not been previously implicated in oral cancer.


Assuntos
Neoplasias Bucais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Idoso , Idoso de 80 Anos ou mais , Catepsina L , Catepsinas/biossíntese , Colagenases/biossíntese , Cisteína Endopeptidases , DNA Complementar/metabolismo , Bases de Dados Factuais , Regulação para Baixo , Células Epiteliais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Mucosa Bucal/patologia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Família Multigênica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Software , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/biossíntese
20.
Biochim Biophys Acta ; 1256(1): 52-6, 1995 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-7742356

RESUMO

The rate constant of quenching of singlet oxygen (kQ) by squalene (SQ) is found to be much larger than those of the lipids in human skin surface. SQ is the first target lipid in human skin surface by oxidative stresses such as sun light exposure. kQ of SQ is similar to that of 3,5-di-t-butyl-4-hydroxytoluene (BHT). The large kQ of SQ is due to the small ionization potential. SQ consists of six 2-methyl-2-pentene units and kQ of SQ is about 6-times as large as that of 2-methyl-2-pentene. The electron donating property of methyl groups bonded to quaternary carbons of SQ is essential to the large kQ. SQ is not very susceptible to peroxidation and is stable for attacks by peroxide radicals. The chain reaction of lipid peroxidation is unlikely to be propagated with SQ in human skin surface. It is concluded that SQ functions as an efficient quencher of singlet oxygen and prevents the corresponding part of lipid peroxidation in human skin surface.


Assuntos
Butanóis/química , Sequestradores de Radicais Livres , Oxigênio/química , Esqualeno/química , 1-Butanol , Radicais Livres , Humanos , Cinética , Peroxidação de Lipídeos , Estresse Oxidativo , Oxigênio Singlete , Pele/metabolismo , Esqualeno/metabolismo , Relação Estrutura-Atividade
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