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1.
Encephale ; 49(3): 211-218, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35331466

RESUMO

OBJECTIVES: Behavior problems are one of the most common reasons for seeking mental health services in pediatric populations. The objectives are to evaluate the effects of the EQUIPE program (Étude Québécoise d'Intervention pour les Parents d'Enfants avec des problèmes de comportement) and to analyze the impact of the severity of behavior problems and of parental characteristics. METHODS: This program was translated from the Community Parent Education Program. The effects of EQUIPE, as compared to a control group, were evaluated by using Child Behavior Checklist and Parent Stress Index questionnaires before (T0) and after the intervention program (T1), and at 6 (T2) and 12months (T3) follow-up visits. RESULTS: In total, 533 participants were enrolled in intervention (n=465) (with "severe" or "mild" subgroups according to CBCL-T score) and a control group (n=68). In the two groups, the results showed a statistically significant decrease in Child Behavior Checklist and Parent Stress Index total scores at T1, T2 and T3, with the exception of Child Behavior Checklist total scores in the control group at T2. In the intervention group Child Behavior Checklist total scores were significantly higher in the "severe"; which was not the case for Parent Stress Index total scores at T2 and T3. DISCUSSION: Socioeconomic characteristics, family details, parental medical history and the age of the children appeared to influence changes in Child Behavior Checklist and Parent Stress Index total scores. CONCLUSION: The EQUIPE program is an effective intervention for reducing behavior problems and parents' stress in a French-Canadian population.


Assuntos
Serviços de Saúde Mental , Pais , Humanos , Criança , Canadá , Pais/psicologia , Relações Mãe-Filho , Comportamento Infantil/psicologia
2.
Oncogene ; 34(44): 5536-47, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-25772245

RESUMO

DEP-1/PTPRJ is a receptor-like protein tyrosine phosphatase mainly known for its antiproliferative and tumor-suppressive functions. Many identified substrates are growth factor receptors, and DEP-1 is deleted and/or mutated in human cancers including that of the breast. However, DEP-1 was also identified as a promoter of Src activation and proinvasive functions in the endothelium, suggesting it could perhaps mediate breast cancer invasiveness that is likewise driven by Src family kinases. We show here that DEP-1 expression was greater in highly invasive breast cancer cells (MDA-MB-231, Hs578T, BT-549) than in the less invasive or untransformed cell lines tested (MCF-7, T47D, SK-BR3 and MCF10A). DEP-1 silencing experiments in invasive cells demonstrated that moderately expressed and catalytically active DEP-1 was required, in collaboration with basal epidermal growth factor receptor activity, for Src activation and the phosphorylation of its substrate Cortactin, and for their colocalization at the cell's leading edge. This correlated with an increased number of cell protrusions, and an enhanced capacity of the cells to migrate and invade. Similarly, moderate overexpression of DEP-1 in the low-invasive cells resulted in the promotion of their invasiveness in an Src-dependent manner. Consistent with these data, the expression of endogenous DEP-1 was elevated in a bone metastatic cell line derived from MDA-MB-231 cells, and promoted increased Src Y418 and Cortactin Y421 phosphorylation, as well as pro-MMP9 secretion and Matrigel invasion. Importantly, the silencing of DEP-1 in MDA-MB-231 cells greatly decreased their ability to metastasize, despite having no effect on tumor growth or angiogenesis. Hence, we found that moderate expression of DEP-1 was associated with the increased relapse and decreased survival of breast cancer patients. These results therefore identify a new and unsuspected role for DEP-1 as a mediator of an invasive cell program implicating Src activation and the promotion of breast cancer progression.


Assuntos
Neoplasias da Mama/genética , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Proteínas Tirosina Fosfatases/genética , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cortactina/genética , Receptores ErbB/genética , Feminino , Humanos , Camundongos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Fosforilação/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Quinases da Família src/genética
3.
Ann Bot ; 104(4): 703-13, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19520701

RESUMO

BACKGROUND AND AIMS: Rubus chamaemorus (cloudberry) is a herbaceous clonal peatland plant that produces an extensive underground rhizome system with distant ramets. Most of these ramets are non-floral. The main objectives of this study were to determine: (a) if plant growth was source limited in cloudberry; (b) if the non-floral ramets translocated carbon (C) to the fruit; and (c) if there was competition between fruit, leaves and rhizomes for C during fruit development. METHODS: Floral and non-floral ramet activities were monitored during the period of flower and fruit development using three approaches: gas exchange measurements, (14)CO(2) labelling and dry mass accumulation in the different organs. Source and sink activity were manipulated by eliminating leaves or flowers or by reducing rhizome length. KEY RESULTS: Photosynthetic rates were lower in floral than in deflowered ramets. Autoradiographs and (14)C labelling data clearly indicated that fruit is a very strong sink for the floral ramet, whereas non-floral ramets translocated C toward the rhizome but not toward floral ramets. Nevertheless, rhizomes received some C from the floral ramet throughout the fruiting period. Ramets with shorter rhizomes produced smaller leaves and smaller fruits, and defoliated ramets produced very small fruits. CONCLUSIONS: Plant growth appears to be source-limited in cloudberry since a reduction in sink strength did not induce a reduction in photosynthetic activity. Non-floral ramets did not participate directly to fruit development. Developing leaves appear to compete with the developing fruit but the intensity of this competition could vary with the specific timing of the two organs. The rhizome appears to act both as a source but also potentially as a sink during fruit development. Further studies are needed to characterize better the complex role played by the rhizome in fruit C nutrition.


Assuntos
Carbono/metabolismo , Frutas/metabolismo , Rosaceae/crescimento & desenvolvimento , Rosaceae/metabolismo , Análise de Variância , Autorradiografia , Biomassa , Metabolismo dos Carboidratos , Dióxido de Carbono/metabolismo , Radioisótopos de Carbono , Fotossíntese , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Rizoma/metabolismo , Coloração e Rotulagem
4.
Rev Epidemiol Sante Publique ; 55(6): 401-12, 2007 Dec.
Artigo em Francês | MEDLINE | ID: mdl-18054187

RESUMO

BACKGROUND: Reforms of care and services have affected primary care physicians, but very little attention has been devoted to their actual participation in Integrated Health Services Network (IHSN). METHODS: From a literature review of articles published from January 1985 to December 2006, we selected 24 studies on physicians' participation in IHSN and their perceptions on practices. RESULTS: This literature review suggests that physicians' perceptions of IHSN are linked to their actual level of participation. Physicians who participated fully perceived improvements in all practice dimensions. Physicians who participated partially were dissatisfied with physician-patient relationships, perceived a loss of professional autonomy and increased gate-keeping constraints. They had however a positive perception of the overall quality of care. When physicians received capitation payments, they were overall dissatisfied. CONCLUSIONS: In order to improve primary care physicians' participation in IHSN, quality of care should be reinforced, capitation payment avoided and gate-keeping should be transformed into coordination of care.


Assuntos
Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Médicos de Família/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Atitude do Pessoal de Saúde , Humanos , Qualidade da Assistência à Saúde , Estados Unidos
5.
Clin Microbiol Infect ; 9(11): 1091-103, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14616725

RESUMO

OBJECTIVE: To evaluate the applicability and adaptability of the bioMérieux VITEK 2 Advanced Expert System (AES) to the customized interpretive susceptibility guidelines used at Dynacare Kasper Medical Laboratories (DKML). METHODS: Three hundred isolates of Enterobacteriaceae (not more than 30% Escherichia coli) were tested on the VITEK 2 system and the API 20E for identification. Susceptibility testing for these isolates was performed on the VITEK 2 system and the Pasco broth microdilution panels. Minimal inhibitory concentrations (MICs) and interpreted results according to the AES and DKML antimicrobial susceptibility guidelines were compared. RESULTS: Of 300 isolates tested for susceptibility, 13 did not give AES interpretations. Of the remaining 287 isolates, interpretations between AES and DKML guidelines were compared for 10 antibiotics. The overall correlation between the AES and DKML interpretations was 96.2%. CONCLUSION: This study demonstrated the benefits and limitations of the bioMérieux AES. Automated knowledge-based systems provide a useful laboratory tool for the interpretation of susceptibility results.


Assuntos
Infecções por Enterobacteriaceae/diagnóstico , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Testes de Sensibilidade Microbiana/métodos , Alberta , Interpretação Estatística de Dados , Humanos , Testes de Sensibilidade Microbiana/normas
6.
Can J Vet Res ; 66(1): 8-14, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11858652

RESUMO

An autogenous vaccine was developed, using sonicated bacteria, with a strain of Streptococcus suis capsular type 1/2. The objectives of this study were to evaluate the antibody response following vaccination and to assess the changes in antibody levels in pigs from a herd showing clinical signs of S. suis capsular type 1/2 infection in 6- to 8-week-old pigs. An enzyme-linked immunosorbent assay using the vaccine antigen was standardized. Results from a preliminary study involving 2 control and 4 vaccinated 4-week-old pigs indicated that all vaccinated pigs produced antibodies against 2 proteins of 34 and 43 kDa, respectively, and, in 3 out of 4 vaccinated pigs, against the 117-kDa muramidase-released protein. For the serologic profile, groups of 30 pigs from the infected herd were blood sampled at 2, 4, 6, 8, and 10 weeks of age. The lowest antibody level was observed between weeks 6 and 8, presumably corresponding to a decrease in maternal immunity. A marked increase was seen at 10 weeks of age, shortly after the onset of clinical signs in the herd. For the vaccination field trial, newly weaned, one-week-old piglets were divided into 2 groups of 200 piglets each (control and vaccinated); blood samples were collected from 36 piglets in each group at 2-week intervals for 12 weeks. A significant increase (P < 0.05) in antibody response was observed 4 weeks following vaccination and the level of antibodies stayed high until the end of the experiment. In the control group, the increase was only observed at 13 weeks of age, probably in response to a natural infection. The response to the vaccine varied considerably among pigs and was attributed, in part, to the levels of maternal antibodies at the time of vaccination. No outbreak of S. suis was observed in the control or vaccinated groups, so the protection conferred by the vaccine could not be evaluated.


Assuntos
Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/imunologia , Doenças dos Suínos/imunologia , Animais , Western Blotting/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Projetos Piloto , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Testes Sorológicos/veterinária , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/prevenção & controle , Streptococcus suis/genética , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária
7.
Vet Res ; 32(2): 175-83, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11361153

RESUMO

Actinobacillus suis is a commensal opportunistic pathogen in swine. However, in recent years, an increasing prevalence of clinical signs associated with A. suis has been observed in high health status herds in North America. The objectives of the study were to assess the kinetics of antibodies to A. suis in pigs from a herd showing clinical signs of A. suis infection and, to evaluate the antibody response in gilts following vaccination with an autogenous vaccine. An enzyme-linked immunosorbent assay (ELISA) using a saline extract of boiled-formalinized whole cells of a field strain as the coating antigen was standardized. This ELISA was used as a tool for monitoring, in a comparative way, the variations in A. suis antibody levels. The herd selected for the serologic profile was negative for Actinobacillus pleuropneumoniae infection and showed clinical signs of A. suis infection in 16 to 19-week-old pigs. A cohort of 20 pigs was blood sampled at 5, 8, 12, and 16 weeks of age. The lowest level of serum antibodies was observed between weeks 8 and 12, this probably corresponding to a decrease in maternal immunity. A marked increase in the antibody response was seen at 16-week of age, at the approximate time of onset of A. suis clinical signs in the herd. The evaluation of serum antibody responses to an autogenous vaccine revealed that the humoral immunity of gilts further increased following vaccination although the level of antibodies was already high prior to vaccination. The magnitude of the response to vaccination was higher when the level of antibodies was low prior to the first injection. The ELISA test seems to detect antibodies against the O-chain LPS.


Assuntos
Infecções por Actinobacillus/veterinária , Actinobacillus/imunologia , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Doenças dos Suínos/imunologia , Infecções por Actinobacillus/imunologia , Fatores Etários , Animais , Vacinas Bacterianas/administração & dosagem , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Sensibilidade e Especificidade , Testes Sorológicos , Suínos
8.
Genes Dev ; 15(7): 833-8, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11297507

RESUMO

The orphan nuclear receptor ERR beta is expressed in undifferentiated trophoblast stem cell lines and extraembryonic ectoderm, and genetic ablation of ERR beta results in abnormal trophoblast proliferation and precocious differentiation toward the giant cell lineage. Here, we show that the synthetic estrogen diethylstilbestrol (DES) promotes coactivator release from ERR beta and inhibits its transcriptional activity. Strikingly, treatment of trophoblast stem cells with DES led to their differentiation toward the polyploid giant cell lineage. In addition, DES-treated pregnant mice exhibited abnormal early placenta development associated with an overabundance of trophoblast giant cells and an absence of diploid trophoblast. These results define a novel pathway for DES action and provide evidence for steroidlike control of trophoblast development.


Assuntos
Dietilestilbestrol/farmacologia , Estrogênios não Esteroides/farmacologia , Etiocolanolona/análogos & derivados , Receptores de Estrogênio/antagonistas & inibidores , Células-Tronco/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , Animais , Células COS , Diferenciação Celular/efeitos dos fármacos , Chlorocebus aethiops , Estradiol/farmacologia , Etiocolanolona/farmacologia , Feminino , Fatores de Crescimento de Fibroblastos/farmacologia , Fluorometria , Genes Reporter , Idade Gestacional , Células Gigantes/patologia , Ligantes , Luciferases/biossíntese , Luciferases/genética , Camundongos , Estrutura Molecular , Coativador 2 de Receptor Nuclear , Placenta/efeitos dos fármacos , Placenta/patologia , Gravidez , Pregnanolona/farmacologia , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores de Estrogênio/fisiologia , Proteínas Recombinantes de Fusão/biossíntese , Células-Tronco/patologia , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Transfecção , Trofoblastos/patologia , Receptor ERRalfa Relacionado ao Estrogênio
9.
Am J Bot ; 88(4): 594-607, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11302844

RESUMO

Because environmental filters are temporally and spatially heterogeneous, there often is a lack of significant relationship between the spatial patterns of successive life stages in plant populations. In this study, we determined the spatiotemporal relationships between different life stages in two populations of an annual plant of the deciduous forests of eastern North America, Floerkea proserpinacoides. Demographic surveys were done over a 4-yr period, and experiments were performed in the field and under controlled conditions to test for the effects of various environmental factors on population dynamics. There was a general lack of relationship between the spatial patterns of seed bank and seedling density, and a lack of similarity between their spatial correlograms. This was related mostly to the effects of spatially variable environmental filters operating on germination and emergence. However, environmental filters acting on plant survival were stable through time and contributed to stabilize the density and spatial patterns of the populations. Despite density-dependent presenescence mortality, spatial patterns of seedlings and mature individuals were similar and their correlograms were alike, suggesting that mortality did not fully compensate for density. Estimated fecundity was negatively correlated with population density over the study period. Although flower production started only 2-3 wk after emergence, seed maturation mostly occurred at the end of the life cycle, just before the onset of plant senescence. Yet, individual fecundity was low for an annual plant, i.e., 3.0 ± 0.5 mature seeds/plant (mean ± 1 SE). Seed predation by vertebrates was not significant. Low soil moisture had little effect on the total number of seeds germinating, although it slowed down the germination process. In quadrats where leaf litter was experimentally doubled, seedling emergence was lower than in control quadrats; in quadrats where leaf litter was completely removed, emergence did not differ from that in control quadrats. Susceptibility to drought stress was higher for seedlings than for mature plants. Although the species does not maintain a long-term persistent soil seed bank, other factors, such as density-dependent fecundity and autogamy, may temper population fluctuations through time and reduce the probability of local extinction.

12.
J Speech Lang Hear Res ; 43(4): 989-96, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11386484

RESUMO

Listeners judged the dissimilarity of pairs of synthesized nasal voices that varied on 3 dimensions. Separate nonmetric multidimensional scaling (MDS) solutions were calculated for each listener and the group. Similar 3-dimensional solutions were derived for the group and each of the listeners, with the group MDS solution accounting for 83% of the total variance in listeners' judgments. Dimension 1 ("Nasality") accounted for 54% of the variance, Dimension 2 ("Loudness") for 18% of the variance, and Dimension 3 ("Pitch") for 11% of the variance. The 3 dimensions were significantly and positively correlated with objective measures of nasalization, intensity, and fundamental frequency. The results of this experiment are discussed in relation to other MDS studies of voice perception, and there is a discussion of methodological issues for future research.


Assuntos
Qualidade da Voz , Humanos , Julgamento , Fonética , Projetos Piloto , Distribuição Aleatória , Reprodutibilidade dos Testes , Percepção da Fala , Voz Alaríngea
13.
Semin Speech Lang ; 20(1): 5-16; quiz 16-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10100373

RESUMO

This article considers quality of life (QOL) with aphasia. The problems surrounding definition and measurement of QOL are reviewed. Dimensions of QOL that have been suggested include elements relating to physical problems, the toxicity dimension, body image and mobility, communication, and psychological, interpersonal, spiritual, and financial issues. These issues are placed in the context of wider dimensions of satisfaction and life quality related to individuality, culture, and philosophical and time elements. Research on the illness experience is related to QOL. Research on QOL after stroke and aphasia is reviewed. Clinical approaches that integrate models of betterment of life quality in aphasia are suggested. Notions of coping and of Aristos, "making the best of a given situation," are considered in the discussion of adjustment and accommodation to life with aphasia.


Assuntos
Afasia/psicologia , Qualidade de Vida , Adaptação Psicológica , Imagem Corporal , Humanos , Satisfação Pessoal
14.
Brain Cogn ; 37(2): 205-23, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9665743

RESUMO

This study investigated the relationship between working memory capacity and reading comprehension in aphasia. A measurement of working memory capacity was obtained using a modified version of Daneman and Carpenter's (1980) Reading Span Task. Sets of sentences ranging in length from one to six words were presented to 22 aphasic subjects who were required to retain the terminal words following each sentence for subsequent recognition. The maximum number of words retrieved was used as an index of working memory capacity. Two versions of the task (listening and reading) were presented depending on the subjects' ability to read. Strong positive correlations were found between working memory capacity, reading comprehension, and language function. These results support the notion that the ability of aphasic individuals to comprehend language is predictable from their working memory capacities.


Assuntos
Afasia/diagnóstico , Transtornos da Memória/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Afasia/etiologia , Transtornos Cerebrovasculares/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
15.
Plant Physiol ; 117(1): 183-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9576787

RESUMO

Leaves are the main source of carbon for fruit maturation in most species. However, in plants seeing contrasting light conditions such as some spring plants, carbon fixed during the spring could be used to support fruit development in the summer, when photosynthetic rates are low. We monitored carbohydrate content in the rhizome (a perennating organ) and the aboveground stem of trillium (Trillium erectum) over the entire growing season (May-November). At the beginning of the fruiting stage, stems carrying a developing fruit were harvested, their leaves were removed, and the leafless stems were maintained in aqueous solution under controlled conditions up to full fruit maturation. These experiments showed that stem carbohydrate content was sufficient to support fruit development in the absence of leaves and rhizome. This is the first reported case, to our knowledge, of complete fruit development sustained only by a temporary carbohydrate reservoir. This carbohydrate accumulation in the stem during the spring enables the plant to make better use of the high irradiances occurring at that time. Many other species might establish short-term carbohydrate reservoirs in response to seasonal changes in growing conditions.

16.
Brain Cogn ; 30(2): 244-53, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8812002

RESUMO

Previous research (LaPointe & Erickson, 1991) has shown that aphasic individuals have difficulty, relative to control subjects, in monitoring for spoken words while performing a secondary task. This finding may indicate that aphasics have fundamental deficits in attention or that their linguistic deficits are simply exacerbated by dividing attention. Twenty subjects, 10 nonfluent aphasic and 10 nonaphasic adults, listened to two 10-min series of nonlinguistic acoustic stimuli across conditions of focused and divided attention. Subjects tried to identify target sounds interspersed with nontarget sounds. As in prior research, aphasic subjects performed less accurately on the auditory vigilance task during the divided attention condition, relative to the undivided attention condition and to control subjects. The findings suggest that deficient cognitive processing, intertwined with linguistic deficit, may underlie auditory comprehension deficits in aphasia and may help explain performance variation within aphasic individuals across tasks.


Assuntos
Afasia de Broca/fisiopatologia , Nível de Alerta , Percepção Auditiva , Encéfalo/fisiopatologia , Idoso , Afasia de Broca/complicações , Nível de Alerta/fisiologia , Atenção/fisiologia , Transtornos Cognitivos/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Invest Radiol ; 30(10): 604-10, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8557500

RESUMO

RATIONALE AND OBJECTIVES: Target-specific magnetic resonance (MR) contrast agents are being developed to improve the accuracy of MR imaging. The purpose of this study was to determine the mechanism of cell uptake, and modes of intracellular trafficking of a prototypical iron oxide label (RMA) used in the synthesis of some target-specific MR contrast agents. METHODS: The prototypical agent (RMA) consisted of a dextran-coated monocrystalline iron oxide that was modified with rhodamine (fluorescent label) and opsonized with albumin. Fluorescence microscopy was performed in a phagocytic C6 cell line and in murine bone marrow macrophages. Immunohistochemistry against lysosomal markers was used to confirm the intracellular location of the label. RESULTS: RMA was identified inside cells after incubation at concentrations as low as 4.0 x 10(-10) M Fe, typically observed with receptor mediated endocytosis and several orders of magnitude lower than that expected with fluid phase pinocytosis. Cell uptake could be inhibited by excess protein but not by dextran. RMA localized initially to tubular and to round intracellular organelles and co-localized with an antibody against a murine lysosomal glycoprotein antibodies (LGP-A) in macrophages. Three days after incubation, RMA was concentrated in perinuclear vesicles, which most likely represent terminal lysosomes where final breakdown appears to occur. CONCLUSIONS: The mechanism of cellular uptake of a prototypical opsonized iron oxide label is consistent with receptor-mediated endocytosis. Immediately after cell contact, RMA localizes to the lysosomal compartment and at long time points reside in vesicles that by morphology and distribution appear to be terminal lysosomes. Iron oxides therefore demonstrate metabolism via the lysosomal pathway.


Assuntos
Meios de Contraste/farmacocinética , Ferro/farmacocinética , Imageamento por Ressonância Magnética , Óxidos/farmacocinética , Albuminas/química , Animais , Células da Medula Óssea , Linhagem Celular , Meios de Contraste/química , Dextranos/química , Dextranos/farmacocinética , Endocitose , Óxido Ferroso-Férrico , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Imuno-Histoquímica , Ferro/química , Lisossomos/metabolismo , Lisossomos/ultraestrutura , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos , Microscopia de Fluorescência , Organelas/metabolismo , Organelas/ultraestrutura , Óxidos/química , Fagócitos/metabolismo , Fagócitos/ultraestrutura , Rodaminas/química , Rodaminas/farmacocinética , Vacúolos/metabolismo , Vacúolos/ultraestrutura
18.
Radiology ; 196(2): 521-7, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7617871

RESUMO

PURPOSE: To map the distribution of an iron oxide label in the central nervous system with in vivo magnetic resonance (MR) imaging. MATERIALS AND METHODS: Unilateral osmotic disruption of the blood-brain barrier (BBB) in rats (n = 40) was followed by injection of monocrystalline iron oxide nanoparticles (MION) into the carotid artery. MR images (1.5 T) were obtained in and ex vivo, and results were correlated with histologic section-matched iron maps. RESULTS: A mean of 0.2% of the injected MION was found in the brain 24 hours after unilateral osmotic disruption of the BBB. The spatial distribution of iron oxide within the brain correlated with areas known to have high relative perfusion. Iron was found in cell bodies and dendrites of cortical neurons and astrocytes and in the interstitial space. The threshold in concentration for detection of MION in the brain was 62.2 ng Fe/mm2. CONCLUSION: MR imaging is well suited to noninvasive in vivo mapping of the intracerebral iron oxide distribution.


Assuntos
Encéfalo/anatomia & histologia , Meios de Contraste , Ferro , Óxidos , Animais , Barreira Hematoencefálica , Encéfalo/metabolismo , Óxido Ferroso-Férrico , Humanos , Ferro/farmacocinética , Imageamento por Ressonância Magnética , Masculino , Óxidos/farmacocinética , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
19.
Genomics ; 24(2): 303-10, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7535287

RESUMO

Keratins are intermediate filament proteins expressed in epithelial cells. They are divided into two groups, type I and type II, that must associate to form filaments. The genes encoding these proteins are clustered in two type-specific loci. In stratified epithelia, differentiation of the basal cells is accompanied by a switch in the expression of keratin genes. However, how this switch is controlled is not yet understood. We report here the cloning and mapping of a 55-kb region surrounding the keratin 19 (K19) gene in the mouse genome. This gene encodes a type I subunit expressed in simple and complex epithelia, notably in nonkeratinizing stratified epithelia of internal organs. In these tissues, it is expressed in basal cells and not in suprabasal cells, where the main type I subunit is keratin 13. Using probes corresponding to highly conserved sequences in intermediate filament proteins, we mapped two other genes downstream from the K19 gene. Restriction mapping and sequencing data indicate that they encode the mouse K15 and K13. The three genes are separated by about 5-6 kb, and they are in the same transcriptional orientation. Because the three genes are expressed together in stratified epithelia and because their order of expression during differentiation is the same as their order on the chromosome, we suggest that there is a relationship between their genomic organization and the control of their expression.


Assuntos
Esôfago/citologia , Queratinas/genética , Família Multigênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/genética , Divisão Celular/genética , DNA Complementar , Células Epiteliais , Epitélio/metabolismo , Esôfago/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Endogâmicos C3H , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
20.
EMBO J ; 11(8): 2971-80, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1639068

RESUMO

Peripherin is a neurone-specific intermediate filament protein expressed mostly in the peripheral nervous system. To localize sequences that are important for the regulation of peripherin gene transcription, we have functionally dissected its promoter. Transfection into different cell lines and deletion mapping of peripherin-lacZ hybrid constructs indicated that the first 98 bp preceding the transcription start site of the gene were sufficient to confer cell-type specific expression. DNase I footprinting experiments revealed three protected sequences in this region, that were named PER1, PER2 and PER3. The PER2 and PER3 elements, localized between -98 to -46, interact with proteins that seem widely distributed. Deletion of these elements severely decreased the level of reporter gene activity. The PER1 element, which overlaps the TATA box, interacts with a DNA-binding protein prevailing in peripherin expressing cell lines. However, the core promoter, which contains the PER1 element, was inefficient in driving gene expression. Experiments designed to test the contribution of each element showed that PER2 and PER3 were important in determining the level of expression, while PER1 was important for cell-type specificity. In fact the polyoma virus enhancer linked to the peripherin gene core promoter was found to limit reporter gene activity to peripherin expressing cell lines. Together, these experiments indicate that co-operative interactions between different regions of the promoter are necessary for efficient and cell-type specific transcription of the peripherin gene in a subset of neuronal cells.


Assuntos
Núcleo Celular/fisiologia , Proteínas de Filamentos Intermediários/genética , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso , Neurônios/fisiologia , Neuropeptídeos/genética , Regiões Promotoras Genéticas , TATA Box , Transcrição Gênica , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Camundongos , Dados de Sequência Molecular , Neuroblastoma , Oligodesoxirribonucleotídeos , Células PC12 , Periferinas , Plasmídeos , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição , Transfecção , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
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