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2.
Nanotechnology ; 20(20): 204015, 2009 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-19420663

RESUMO

Mg50Co50 alloy before and after hydrogenation was investigated by means of transmission electron microscopy (TEM). Mg50Co50 alloy before hydrogenation was found to contain crystals not larger than 5 nm in size. Selected-area electron diffraction patterns (SAEDPs) revealed that these nanocrystals have a body-centered cubic (BCC) structure with a lattice parameter of about 0.3 nm. Distribution of Mg and Co elements in the Mg50Co50 alloy was uniform, indicated by energy dispersive x-ray spectroscopy (EDS) analysis. Crystallization and decomposition occurred in the Mg50Co50 alloy during hydrogenation. A large number of crystals larger than 10 nm were observed in the hydrogenated sample. The SAEDPs showed polycrystalline rings corresponding to the BCC phase and the Co metal phase. The existence of Mg-rich Mg-Co crystals and Co particles was also confirmed by TEM-EDS analysis.


Assuntos
Cobalto/química , Cristalização/métodos , Hidrogênio/química , Compostos de Magnésio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Ligas/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
3.
J Thromb Haemost ; 4(11): 2478-85, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16970803

RESUMO

Disruptions of circadian rhythms are associated with the development of many disorders. However, whether a disruption of the circadian clock can cause anomalies of the hemostatic balance remains unknown. The present study examines coagulation and fibrinolytic activities in circadian clock mutants, a homozygous Clock mutant and Cry1/Cry2 double knockout (Cry1/2-deficient) mice. The euglobulin clot lysis time (ELT) showed circadian variations that peaked at 21:00 (early night) in wild-type mice, suggesting that fibrinolytic activity is lowest at this time. The ELT was continuously reduced in Clock mutants, while the ELT was significantly increased and did not differ between day and night (9:00 and 21:00) in Cry1/2-deficient mice. The prothrombin time (PT) and activated partial prothrombin time (APTT) were constant in all genotypes. To identify which factors cause the loss of ELT rhythm, we measured fibrinolytic parameters in Clock mutant and Cry1/2-deficient mice. The robust circadian fluctuation of plasma plasminogen activator inhibitor 1 (PAI-1) that peaked at early night was damped to trough levels in Clock mutant mice. On the other hand, PAI-1 levels in Cry1/2-deficient mice remained equivalent to the peak levels of those in wild-type mice at both 9:00 and 21:00. Circadian changes in plasma PAI-1 levels seemed to be regulated at the level of gene expression, because the plasma PAI-1 levels in Clock mutant and Cry1/2-deficient mice were closely correlated with the level of PAI-1 mRNA transcript in these mice. Plasma plasminogen and hepatic mRNA levels were not rhythmic in wild-type mice, and continuously higher in Clock mutant than in wild-type or Cry1/2-deficient mice. In contrast, the activity and mRNA levels of tissue type plasminogen activator (t-PA), plasma levels and mRNA levels of plasminogen, and plasma levels of alpha2 plasmin inhibitor (alpha2PI) in all genotypes were constant throughout the day. Coagulation parameters such as factor VII, factor X, prothrombin and fibrinogen remained constant throughout the day, and were not affected by clock gene mutations. These results suggest that circadian clock molecules play an important role in hemostatic balance by regulating the fibrinolytic systems.


Assuntos
Ritmo Circadiano , Fibrinólise , Flavoproteínas/metabolismo , Inibidor 1 de Ativador de Plasminogênio/sangue , Transativadores/metabolismo , Animais , Antifibrinolíticos/sangue , Proteínas CLOCK , Ritmo Circadiano/genética , Criptocromos , Fibrinólise/genética , Flavoproteínas/genética , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Mutantes , Inibidor 1 de Ativador de Plasminogênio/genética , Transativadores/genética
4.
J Thromb Haemost ; 4(8): 1774-80, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16879220

RESUMO

BACKGROUND: An increased level of obesity-induced plasma plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular disease. AIM: The present study investigates whether the circadian clock component CLOCK is involved in obesity-induced PAI-1 elevation. METHODS: We examined plasma PAI-1 and mRNA expression levels in tissues from leptin-deficient obese and diabetic ob/ob mice lacking functional CLOCK protein. RESULTS: Our results demonstrated that plasma PAI-1 levels were augmented in a circadian manner in accordance with the mRNA expression levels in ob/ob mice. Surprisingly, a Clock mutation normalized the plasma PAI-1 concentrations in accordance with the mRNA levels in the heart, lung and liver of ob/ob mice, but significantly increased PAI-1 mRNA levels in adipose tissue by inducing adipocyte hypertrophy in ob/ob mice. The Clock mutation also normalized tissue PAI-1 antigen levels in the liver but not in the adipose tissue of ob/ob mice. CONCLUSION: These observations suggest that CLOCK is involved in obesity-induced disordered fibrinolysis by regulating PAI-1 gene expression in a tissue-dependent manner. Furthermore, it appears that obesity-induced PAI-1 production in adipose tissue is not closely related to systemic PAI-1 increases in vivo.


Assuntos
Fibrinólise , Regulação da Expressão Gênica , Obesidade/genética , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Transativadores/fisiologia , Tecido Adiposo/metabolismo , Animais , Proteínas CLOCK , Ritmo Circadiano , Heterozigoto , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Obesos , Fatores de Tempo , Transativadores/metabolismo
5.
J Hosp Infect ; 63(3): 298-305, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16650506

RESUMO

Although 2% glutaraldehyde is often the first-line agent for endoscopic disinfection, its adverse reactions are common among staff and it is less effective against certain mycobacteria and spore-bearing bacteria. Chlorine dioxide is a possible alternative and an automated washer-disinfector fitted with this agent is currently available. This study was conducted to evaluate the effectiveness of chlorine dioxide in endoscopic disinfection after upper gastrointestinal examination. In vitro microbicidal properties of chlorine dioxide solutions were examined at high (600 ppm) and low (30 ppm) concentrations against various microbes including Pseudomonas aeruginosa, Helicobacter pylori, Mycobacterium avium-intracellulare and Bacillus subtilis in the presence or absence of bovine serum albumin (BSA). Immediately following endoscopic procedures and after application to the automated reprocessor incorporating chlorine dioxide at 30 ppm for 5 min, endoscopic contamination with infectious agents, blood, H. pylori ureA gene DNA and HCV-RNA was assessed by cultivation, sensitive test tape, polymerase chain reaction (PCR) and reverse transcriptase-PCR analysis, respectively. Chlorine dioxide at 30 ppm has equivalent microbicidal activity against most microbes and faster antimicrobial effects on M. avium-intracellulare and B. subtilis compared with 2% glutaraldehyde, but contamination with BSA affected the microbicidal properties of chlorine dioxide. Endoscopic contamination with microbes, blood and bacterial DNA was eliminated after application of the automated reprocessor/chlorine dioxide system. Thus, chlorine dioxide is a potential alternative to glutaraldehyde. The use of automated reprocessors with compatibility to chlorine dioxide, coupled with thorough pre-cleaning, can offer effective, faster and less problematic endoscopic disinfection.


Assuntos
Bactérias/isolamento & purificação , Compostos Clorados , Desinfetantes de Equipamento Odontológico , Desinfecção/métodos , Endoscópios Gastrointestinais/microbiologia , Glutaral , Óxidos , Contaminação de Equipamentos
6.
Cytogenet Genome Res ; 113(1-4): 223-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16575184

RESUMO

The imprinted region on mouse distal chromosome 12 covers about 1 Mb and contains at least three paternally expressed genes (Pegs: Peg9/Dlk1, Peg11/Rtl1, and Dio3) and four maternally expressed genes (Megs: Meg3/Gtl2, antiPeg11/antiRlt1, Meg8/Rian, and Meg9/Mirg). Gtl2(lacZ) (Gene trap locus 2) mice have a transgene (TG) insertion 2.3 kb upstream from the Meg3/Gtl2 promoter and show about 40% growth retardation when the TG-inserted allele is paternally derived. Quantitative RT-PCR experiments showed that the expression levels of Pegs in this region were reduced below 50%. These results are consistent with the observed phenotype in Gtl2lacZ mice, because at least two Pegs(Peg9/Dlk1 and Dio3) have growth-promoting effects. The aberrant induction of Megs from silent paternal alleles was also observed in association with changes in the DNA methylation level of a differentially methylated region (DMR) located around Meg3/Gtl2 exon 1. Interestingly, a 60 approximately 80% reduction in all Megs was observed when the TG was maternally derived, although the pups showed no apparent growth or morphological abnormalities. Therefore, the paternal or maternal inheritance of the TG results in the down-regulation in cis of either Pegs or Megs, respectively, suggesting that the TG insertion influences the mechanism regulating the entire imprinted region.


Assuntos
Impressão Genômica , Proteínas/genética , Animais , Sequência de Bases , Aberrações Cromossômicas , Mapeamento Cromossômico , Primers do DNA , Feminino , Regulação da Expressão Gênica , Transtornos do Crescimento/genética , Masculino , Camundongos , Camundongos Transgênicos , Mutagênese Insercional , RNA Longo não Codificante , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta-Galactosidase/genética
7.
Lupus ; 12(2): 117-23, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12630756

RESUMO

We conducted this study to confirm whether or not Ca2+-dependent antiprothrombin antibody (aPT) in patients' sera with systemic lupus erythematosus and/or primary antiphospholipid syndrome would react to prothrombin/phosphatidylserine in the presence of Sr2+, Mn2+ or Ba2+, or divalent metal ions like Ca2+, utilizing ELISA, and to analyze the clinical significance of these metal-dependent aPT. We found the presence of Ba2+- and Sr2+-dependent IgG, IgM and IgA-aPT in up to 65% of patients negative for Ca2+-dependent IgG-, IgM and IgA-aPT. Maximally 69% of them were complicated by antiphospholipid syndrome-related symptoms. These data suggest that the measurement of Ba2+- and Sr2+- along with Ca2+-dependent aPT may become a clinically useful tool to correctly detect patients with antiphospholipid-related complications. However, further study is needed to clarify the clinicopathological differences among these aPTs in the future.


Assuntos
Síndrome Antifosfolipídica/imunologia , Autoanticorpos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Protrombina/imunologia , Adulto , Síndrome Antifosfolipídica/complicações , Bário , Cátions Bivalentes , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Fosfatidilserinas/imunologia , Estrôncio
8.
Acta Paediatr Suppl ; 92(443): 54-62; discussion 45, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14989467

RESUMO

UNLABELLED: Spontaneously occurring genetic lysosomal storage diseases are as rare in other mammalian species as in man. However, the advent of gene targeting technology has revolutionized the state of animal models of genetic diseases. Nearly all lysosomal storage diseases known in man have been duplicated in the mouse. The technology now allows, not only complete inactivation of endogenous genes, but also the introduction of essentially any type of mutation. These animal models can overcome many of the limitations inherent in studies of human patients--rarity of the disease, extremely complex genetic background and logistical and ethical constraints in the design and execution of experiments with human subjects. For example, genetic manipulations of germ cells or cross-breeding experiments between two mutants are readily feasible with animal models. Two major areas of the utility of animal models are the clarification of the pathophysiology/pathogenetic mechanism of disease and the exploration of therapeutic approaches. Examples of experiments using animal models of lysosomal storage disease are presented, primarily from studies undertaken in our own laboratory. CONCLUSION: Animal models have proved invaluable in extending our knowledge of the lysosomal storage diseases and exploring potential therapies.


Assuntos
Modelos Animais de Doenças , Doenças por Armazenamento dos Lisossomos/fisiopatologia , Animais , Transplante de Medula Óssea , Dependovirus , Feminino , Galactosilceramidase/metabolismo , Vetores Genéticos , Glicoproteínas/genética , Humanos , Hibridização Genética , Leucodistrofia de Células Globoides/fisiopatologia , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/terapia , Complexo Principal de Histocompatibilidade/fisiologia , Camundongos , Camundongos Knockout , Gravidez , Saposinas , Transgenes
9.
Blood Coagul Fibrinolysis ; 13(8): 697-702, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12441908

RESUMO

Recently, an enzyme-linked immunosorbent assay (ELISA) using prothrombin (PT) as the antigen has become a widely used test. Two ELISA methods for the detection of antiprothrombin antibody have been used extensively: one method employs PT as an antigen (aPT), and the other employs PT and phosphatidyl serine (aPT/PS) as antigens along with Ca. However, the results obtained by the two methods are not necessarily consistent with each other even using the same samples, suggesting the possibility that aPT and aPT/PS are different antibodies. We conducted an investigation to determine whether aPT and aPT/PS are identical or different antibodies. Five patients who were positive for both tests become negative to aPT after absorption with an aPT-ELISA plate or fluid-phase PT; however, they retained reactivity to aPT/PS after the same absorption procedure. These results suggest that aPT and aPT/PS are partially identical, yet still different antibodies. However, further examination employing more samples may be needed to verify our hypothesis including clarification of the clinicopathological significance of these antibodies in the future.


Assuntos
Autoanticorpos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Fosfatidilserinas/imunologia , Protrombina/imunologia , Adulto , Especificidade de Anticorpos , Autoanticorpos/sangue , Cálcio , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Inibidor de Coagulação do Lúpus/imunologia , Masculino , Pessoa de Meia-Idade
11.
Hum Mol Genet ; 10(23): 2709-15, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11726558

RESUMO

Globoid cell leukodystrophy is one of the classical genetic leukodystrophies in humans. The typical infantile disease in man (Krabbe disease) is caused by deficiency of lysosomal galactosylceramidase. We recently generated a new mouse model of a late-onset, chronic form of the disease by inactivating saposin A, the essential activator of galactosylceramidase. The phenotypic features of saposin A(-/-) mice are qualitatively identical but milder than those of twitcher mice, which is caused by genetic galactosylceramidase deficiency. During intercrossing of saposin A(-/-) mice, we observed that affected females that are continually pregnant showed greatly improved neurological symptoms compared to affected females that do not experience pregnancy, or affected males. The pathological hallmark of globoid cell leukodystrophy, demyelination with infiltration of globoid cells, largely disappeared. The immune-related gene expression (MCP-1, TNF-alpha) was significantly down-regulated in the brain of pregnant saposin A(-/-) mice. In addition, we found intense expression of the estrogen receptors (ER alpha and ER beta) on the globoid cells, activated astrocytes and microglia in the demyelinating area of saposin A(-/-) mice. When saposin A(-/-) mice were subcutaneously implanted with time-release 17 beta-estradiol (E2) pellets from 30 to 90 days, the pathology was vastly improved. These findings suggest that a higher level of estrogen during pregnancy is one of the important factors in the protective effect of pregnancy. While we should be cautious in extrapolating these observations in the mouse to human disease, the phenomenon is spectacularly dramatic and estrogen administration might be worth a consideration as a supplementary treatment for some chronic genetic leukodystrophies.


Assuntos
Leucodistrofia de Células Globoides/genética , Animais , Antígenos CD/genética , Encéfalo/metabolismo , Quimiocina CCL2/genética , Modelos Animais de Doenças , Estradiol/farmacologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios/farmacologia , Feminino , Expressão Gênica , Glicoproteínas/genética , Imuno-Histoquímica , Interleucina-10/genética , Leucodistrofia de Células Globoides/patologia , Leucodistrofia de Células Globoides/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Mutantes , Mutação , Sistema Nervoso/patologia , Nervos Periféricos/patologia , Fenótipo , Gravidez , Psicosina/metabolismo , RNA/genética , RNA/metabolismo , Receptores de Estrogênio/biossíntese , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saposinas , Taxa de Sobrevida , Fatores de Tempo , Fator de Necrose Tumoral alfa/genética
12.
J Neuropathol Exp Neurol ; 60(11): 1062-74, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11706936

RESUMO

Twitcher (twi/twi) is a murine model of a human genetic demyelinating disease, globoid cell leukodystrophy (Krabbe disease). The affected mice usually die before reaching age 45 days, having demyelination associated with extensive glial activation. The twi/twi mice that receive wild-type bone marrow transplantation (BMT) survive up to 3 times longer with improved pathology. We hypothesize that immune-related molecules such as cytokines and chemokines are partly responsible for the demyelination in twi/twi, and that the decrease in the expression of such molecules following BMT contributes to clinico-pathological improvement. Cells expressing TNF-alpha, MCP-1, and MIP-1beta were conspicuous in the twi/twi CNS accompanied by infiltration of Ia+ and CD8+/CD3- hematogenous cells. These cells decreased gradually after BMT TNF-alpha mRNA and mRNA of C-C chemokine families, including MCP-1, IP-10, MIP-1alpha, MIP-1beta, and RANTES, were upregulated in the twi/twi CNS but downregulated gradually following BMT. In twi/twi that survived to 20 wk of age, cells expressing TNF-alpha, MCP-1, MIP-1beta, Ia, or CD8 were hardly detected and pathology was clearly improved. These results are consistent with the hypothesis that cytokine expression in glial cells contributes (to some extent) to the pathogenesis of demyelinating lesions in the twi/twi mice.


Assuntos
Transplante de Medula Óssea/imunologia , Citocinas/metabolismo , Leucodistrofia de Células Globoides/imunologia , Leucodistrofia de Células Globoides/terapia , Animais , Astrócitos/química , Astrócitos/patologia , Complexo CD3/análise , Antígenos CD8/análise , Quimiocina CCL2/análise , Quimiocina CCL2/metabolismo , Quimiocina CCL3 , Quimiocina CCL4 , Citocinas/análise , Regulação para Baixo/imunologia , Imuno-Histoquímica , Interleucina-10/análise , Interleucina-10/metabolismo , Leucodistrofia de Células Globoides/patologia , Proteínas Inflamatórias de Macrófagos/análise , Proteínas Inflamatórias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes Neurológicos , Camundongos Transgênicos , Microglia/química , Microglia/patologia , Microscopia Eletrônica , Fibras Nervosas Mielinizadas/imunologia , Fibras Nervosas Mielinizadas/ultraestrutura , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo
13.
Brain Dev ; 23(6): 379-84, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11578847

RESUMO

A deficiency of lysosomal acid beta-galactosidase leads to G(M1)-gangliosidosis in humans, which progressively and profoundly affects the brain and other organs mainly in the early infantile period. We report the pathology of mice with targeted disruption of the beta-galactosidase gene. In the central nervous system, vacuolated neurons appeared in the spinal cord 3 days after birth. The vacuolation extended to neurons in the brainstem, cerebral cortex, hippocampus and thalamus and ballooning neurons became prominent with age. The vacuolation also appeared in Purkinje cells without a marked ballooning change. Reactive astrogliosis in the entire brain was marked at the terminal stage of the disease. Immunohistochemical study using anti-ganglioside G(M1) and G(A1) antibodies revealed extensive accumulation of G(M1) and G(A1) in the cerebral neurons. In the liver, however, accumulation of G(M1) was localized in the cytoplasm of hepatocytes, whereas that of G(A1) was localized in foamy macrophages and Kupffer cells. There were no significant abnormalities in the bone, bone marrow, or cornea at any stage. Although there are some phenotypic and biochemical differences between this knockout mouse and human GM1 gangliosidosis, the mouse will be a useful model for therapeutic trials for the human disease.


Assuntos
Gangliosidose GM1/genética , Doenças por Armazenamento dos Lisossomos/genética , beta-Galactosidase/genética , Animais , Gangliosidose GM1/patologia , Humanos , Imuno-Histoquímica , Doenças por Armazenamento dos Lisossomos/patologia , Lisossomos/enzimologia , Lisossomos/patologia , Camundongos , Camundongos Knockout , Sistema Nervoso/patologia
14.
Proc Natl Acad Sci U S A ; 98(22): 12636-41, 2001 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-11592984

RESUMO

CD1d-restricted natural killer (NK) T cells reactive with the glycolipid alpha-galactosylceramide (alpha-GalCer) are a distinct lymphocyte sublineage. They express an invariant Valpha14-Jalpha18 T cell receptor (TcR), but the role of the beta chain has been controversial. Here, we have used CD1d tetramers to identify and isolate NK T cells based on their antigen specificity. In mice lacking germline Vbeta8, most of the alpha-GalCer-reactive T cells express either Vbeta2 or Vbeta7, strong Vbeta selection being revealed by the lack of an increase in other Vbeta regions. By contrast to the selection for complementarity determining region (CDR) 3beta sequences in some anti-peptide responses, alpha-GalCer-reactive T cells have polyclonal CDR3beta sequences. There is little CDR3beta sequence redundancy between organs or individual mice, and, surprisingly, there also is no evidence for organ-specific CDR3beta sequence motifs. These data argue against a T cell receptor-mediated self-reactivity for tissue-specific CD1d-bound ligands. Each NKT clone is represented by only 5-10 cells. This clone size is similar to naive conventional T cells, and much lower than that reported for memory T cells, although NK T cells have an activated/memory phenotype.


Assuntos
Galactosilceramidas/imunologia , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T , Células Matadoras Naturais/imunologia , Animais , Antígenos CD1/imunologia , Antígenos CD1d , Regiões Determinantes de Complementaridade , Epitopos , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos
15.
Ann Surg Oncol ; 8(9 Suppl): 86S-89S, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11599910

RESUMO

Although the sentinel node (SN) concept has been validated in malignant melanoma and breast cancer, the application of this concept for other solid tumors, including gastrointestinal (GI) cancer, is still controversial. We have demonstrated the feasibility of radioguided SN mapping during laparotomy in patients with esophageal, gastric, and colorectal cancers. In 188 patients, the SNs identified by this technique had an overall diagnostic accuracy of 96% for regional lymph node metastasis. Aberrant drainage sites that have been called skip metastasis from the primary lesion were detectable using this method. More recently, we have undertaken SN mapping during laparoscopic surgery. A combination of radiotracer and blue dye optimized the identification of SNs that drained GI cancers. Our preliminary data indicate that laparoscopic mapping of the SN is a sensitive intraoperative technique for identifying lymph node micrometastasis, and we believe that it will become an important component of a minimally invasive approach to early-stage GI cancers.


Assuntos
Neoplasias Gastrointestinais/patologia , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/patologia , Corantes , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Neoplasias Gastrointestinais/diagnóstico por imagem , Humanos , Queratinas/análise , Laparoscopia/métodos , Metástase Linfática , Cintilografia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Agregado de Albumina Marcado com Tecnécio Tc 99m
16.
Nat Immunol ; 2(10): 971-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11550008

RESUMO

CD1d-reactive NKT cells are a separate T cell sublineage. Instructive models propose that NKT cells branch off the mainstream developmental pathway because of their T cell antigen receptor specificity, whereas stochastic models would propose that they develop from precursor cells committed to this sublineage before variable-gene rearrangement. We show here that immature double-positive (DP) thymocytes form the canonical rearranged Valpha gene of NKT cells at nearly equivalent frequencies in the presence or absence of CD1d expression. After interacting with CD1d in the thymus, these cells give rise to expanded populations of NKT cells-including both CD4+ and double-negative lymphocytes in the thymus and periphery-that express this alpha chain. These results confirm the existence of a DP intermediate for CD1d-reactive NKT cells. They also show that the early developmental stages of these T cells are not governed by a distinct mechanism, which is consistent with the TCR-instructive model of differentiation.


Assuntos
Antígenos CD1/análise , Subpopulações de Linfócitos T/imunologia , Timo/imunologia , Animais , Antígenos CD1/genética , Antígenos CD1d , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Galactosilceramidas/metabolismo , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Região de Junção de Imunoglobulinas/biossíntese , Região de Junção de Imunoglobulinas/genética , Região Variável de Imunoglobulina/biossíntese , Região Variável de Imunoglobulina/genética , Imunofenotipagem , Ativação Linfocitária , Camundongos , Camundongos Knockout , RNA Mensageiro/biossíntese , Células-Tronco/citologia , Subpopulações de Linfócitos T/classificação , Timo/crescimento & desenvolvimento
17.
Jpn J Antibiot ; 54(7): 331-64, 2001 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-11560054

RESUMO

From October 1999 to September 2000, we collected the specimen from 430 patients with lower respiratory tract infections in 17 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and antibiotics and patients' characteristics. Of 515 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 506 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 101, Haemophilus influenzae 104, Pseudomonas aeruginosa (non-mucoid) 58, P. aeruginosa (mucoid) 11, Moraxella subgenus Branhamella catarrhalis 41, Klebsiella pneumoniae 18, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or above of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 57.7%. Vancomycin and arbekacin showed the most potent activities against MRSA without detection of ABK-resistant strain (MIC: 64 micrograms/ml) and decrease of VCM-sensitive strains those were found in 1998. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) decreased to 34.7% from 46.0% in 1998. The frequency of PRSP was 3.0%, being the least number after 1991. Carbapenems showed strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 101 strains with MIC of 0.063 microgram/ml. Generally, all drugs showed strong activities against H. influenzae with MIC80s of 4 micrograms/ml or below. MICs of ofloxacin ranged between 0.063 microgram/ml and 4 micrograms/ml in 1998, however, those were 0.125 microgram/ml or below in all H. influenzae in 1999 showing the strongest activity. Tobramycin and ciprofloxacin showed strong activities against P. aeruginosa (both mucoid and non-mucoid) with MIC80s of 1 microgram/ml. Number of isolated P. aeruginosa (mucoid) was little as 11, however, the susceptibilities to all drugs were better than P. aeruginosa (non-mucoid). K. pneumoniae showed good susceptibilities to all drugs except for ampicillin with decreasing of low-sensitive strains compared to those detected in 1998. Also, all drugs generally showed strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or below. The drug which showed the strongest activity was imipenem inhibiting all 41 strains with MIC of 0.063 microgram/ml. On the patients' characteristics, the number of patients aged 80 years or older who had been increased was decreased in 1999 in the distribution by age. The percentage of the elderly patients aged 70 years or older was 47.0%, which occupied almost a half number of the total patients as in the last year. As for the incidence by disease, bacterial pneumonia and chronic bronchitis were the highest. They were noted in 37.9% and 30.5% of the patients, respectively. In 1999, bronchial asthma was frequently observed as compared in recent years. It was noted in about 10% of the patients which is the same % as in bronchiectasis. We examined the number of strains from these patients with infections before and after administration of antibiotics. In patients with bacterial pneumonia, the number of isolated strains was almost the same between those before and after administration. However, in patients with chronic bronchitis, the number of strains remarkably decreased to less than the half of the total after administration of antibiotics in the last year, but it decreased to 2/3 of the total in 1999. On the administration of antibiotics and isolated bacteria by the day of administration, the bacteria which were isolated more before administration were H. influenzae in 28.4%, S. pneumoniae in 25.7%, M. (B.) catarrhalis in 12.0% and S. aureus in 10.6%. The frequency of S. aureus after administration over 15 days was almost the same as that before administration, but the frequency of P. aeruginosa (both mucoid and non-mucoid) was 36.8% which was higher than that before administration. The frequency of isolated S. pneumoniae was decreased after administration and none of them was isolated after completion of administration. However, that of H. influenzae was decreased to 7.1% after administration within 3 days, and many H. influenzae were isolated after completion of administration as 21.4%.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Respiratórias/microbiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Resistência a Medicamentos , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Fatores de Tempo
18.
Endocrinology ; 142(10): 4189-94, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11564673

RESUMO

Uncoupling protein 3 (UCP3), which uncouples electron transport from ATP synthesis, is expressed at high levels in the skeletal muscle, an important organ in glucose and lipid metabolism. Because several reports proposed that fatty acids induced UCP3 gene expression in skeletal muscle in vivo, in the present study we examined the regulation of UCP3 gene expression by various fatty acids using L6 myotubes. UCP3 gene expression was increased in L6 myotubes by various fatty acids or by alpha-bromopalmitate, a nonmetabolized derivative of palmitic acid. Because fatty acids are also known as agonists for PPARs, we examined the involvement of PPARs in the regulation of the UCP3 gene expression. L-165041, a PPAR delta agonist, increased UCP3 gene expression in L6 myotubes, whereas neither Wy 14,643, a PPAR alpha agonist, nor Pioglitazone, a PPAR gamma agonist, increased it. Therefore, we conclude that UCP3 gene expression is increased by the activation of PPAR delta in L6 myotubes and postulate that PPAR delta mediates at least some part of the increased UCP3 gene expression by fatty acids in skeletal muscle in vivo.


Assuntos
Proteínas de Transporte/genética , Músculo Esquelético/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Animais , Linhagem Celular , Ácidos Graxos/farmacologia , Canais Iônicos , Proteínas Mitocondriais , Ratos , Receptores Citoplasmáticos e Nucleares/agonistas , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/agonistas , Proteína Desacopladora 3 , Regulação para Cima/efeitos dos fármacos
19.
Brain Dev ; 23(5): 284-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504597

RESUMO

Ten low molecular compounds analogous to galactose were screened for inhibition of human beta-galactosidase activity. Among them, 1-deoxy-galactonojirimycin and N-(n-butyl)-deoxy-galactonojirimycin showed an inhibitory effect at high concentrations. However, they restored mutant enzyme activities expressed in enzyme-deficient knockout mouse fibroblasts and human beta-galactosidosis fibroblasts at lower intracellular concentrations. This effect was more remarkable on G(M1)-gangliosidosis mutations (R201C, I51T, R201H, R457Q) than Morquio B disease mutations (W273L, Y83H). These low molecular compounds pass though the blood-brain barrier in mice. We hope that this new therapeutic approach will become clinically applicable in the near future.


Assuntos
1-Desoxinojirimicina/farmacologia , Células Cultivadas/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gangliosidose GM1/tratamento farmacológico , Mucopolissacaridose IV/tratamento farmacológico , beta-Galactosidase/antagonistas & inibidores , 1-Desoxinojirimicina/análogos & derivados , Animais , Células Cultivadas/citologia , Células Cultivadas/enzimologia , DNA Complementar/efeitos dos fármacos , DNA Complementar/farmacologia , Fibroblastos/citologia , Fibroblastos/enzimologia , Gangliosidose GM1/enzimologia , Gangliosidose GM1/fisiopatologia , Humanos , Camundongos , Camundongos Knockout/genética , Camundongos Knockout/metabolismo , Mucopolissacaridose IV/enzimologia , Mucopolissacaridose IV/fisiopatologia , Mutação/efeitos dos fármacos , Mutação/fisiologia , beta-Galactosidase/deficiência , beta-Galactosidase/genética
20.
Neurochem Res ; 26(6): 667-71, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11519726

RESUMO

Cytotoxic capacity of psychosine (galactosylsphingosine) was evaluated in comparison with C6-ceramide in cultured fibroblasts and the glia-derived MOCH-1 cells that have characteristics of myelinating cells (1). Psychosine caused cytotoxic cell death and DNA fragmentation at concentrations similar to C6-ceramide and MOCH-1 cells were substantially more sensitive to their cytotoxic effects than fibroblasts. In this system, pretreatment with GM1-ganglioside failed to protect the cells from the deleterious effects of these compounds. These findings are consistent with the hypothesis that psychosine is the cytotoxic metabolite that causes apoptotic death of the oligodendrocyte in globoid cell leukodystrophy (Krabbe disease). They further suggest that the protective capacity of GM1-ganglioside is unlikely to be the explanation for the paradoxical improvement of the phenotype of globoid cell leukodystrophy in the mouse simultaneously deficient in two lysosomal beta-galactosidases, galactosylceramidase and GM1-ganglioside beta-galactosidase.


Assuntos
Ceramidas/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Psicosina/farmacologia , Sais de Tetrazólio/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ceramidas/antagonistas & inibidores , Fragmentação do DNA/efeitos dos fármacos , Gangliosídeo G(M1)/farmacologia , Camundongos , Psicosina/antagonistas & inibidores
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