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1.
Differentiation ; 79(4-5): 232-43, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20395036

RESUMO

The cellular response to materials implanted in the peritoneal cavity has been utilised to produce tissue for grafting to hollow smooth muscle organs (blood vessels, bladder, uterus and vas deferens). To gain insight into the regulatory mechanisms involved in encapsulation of a foreign object, and subsequent differentiation of encapsulating cells, the present study used microarray technology and real-time RT-PCR to identify the temporal changes in gene expression associated with tissue development. Immunohistochemical analysis showed that 3-7 days post-implantation of foreign objects (cubes of boiled egg white) into rats, they were encapsulated by tissue comprised primarily of haemopoietic (CD45(+)) cells, mainly macrophages (CD68(+), CCR1(+)). By day 14, tissue capsule cells no longer expressed CD68, but were positive for myofibroblast markers alpha-smooth muscle (SM) actin and SM22. In accordance with these results, gene expression data showed that early capsule (days 3-7) development was dominated by the expression of monocyte/macrophage-specific genes (CD14, CSF-1, CSF-1R, MCP-1) and pro-inflammatory mediators such as transforming growth factor (TGF-beta). As tissue capsule development progressed (days 14-21), myofibroblast-associated and pro-fibrotic genes (associated with TGF-beta and Wnt/beta-catenin signalling pathways, including Wnt 4, TGFbetaRII, connective tissue growth factor (CTGF), SMADs-1, -2, -4 and collagen-1 subunits) were significantly up-regulated. The up-regulation of genes associated with Cardiovascular and Skeletal and Muscular System Development at later time-points suggests the capacity of cells within the tissue capsule for further differentiation to smooth muscle, and possibly other cell types. The identification of key regulatory pathways and molecules associated with the fibrotic response to implanted materials has important applications not only for optimising tissue engineering strategies, but also to control deleterious fibrotic responses.


Assuntos
Fibrose/fisiopatologia , Reação a Corpo Estranho , Cavidade Peritoneal/patologia , Animais , Biomarcadores/metabolismo , Fibrose/patologia , Reação a Corpo Estranho/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Implantes Experimentais , Análise em Microsséries , Cavidade Peritoneal/anatomia & histologia , Cavidade Peritoneal/fisiologia , Ratos , Ratos Wistar
2.
Sex Transm Infect ; 85 Suppl 2: ii3-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19307348

RESUMO

OBJECTIVES: To distinguish between three distinct groups of male and transgender sex workers in Pakistan and to demonstrate how members of these stigmatized groups need to be engaged in the research process to go beyond stated norms of behaviour. METHODS: A peer ethnography study was undertaken in a major city in Pakistan. 15 male and 15 transgender sex workers were trained as peer researchers to each interview three peers in their network. Analysis was based on interviews with peer researchers as well as observation of dynamics during training and analysis workshops. RESULTS: The research process revealed that, within the epidemiological category of biological males who sell sex, there are three sociologically different sexual identities: khusras (transgender), khotkis (feminized males) and banthas (mainstream male identity). Both khusras and khotkis are organised in strong social structures based on a shared identity. While these networks provide emotional and material support, they also come with rigid group norms based on expected "feminine" behaviours. In everyday reality, sex workers showed fluidity in both behaviour and identity according to the situational context, transgressing both wider societal and group norms. The informal observational component in peer ethnography was crucial for the accurate interpretation of interview data. Participant accounts of behaviour and relationships are shaped by the research contexts including who interviews them, at what stage of familiarity and who may overhear the conversation. CONCLUSIONS: To avoid imposing a "false clarity" on categorisation of identity and assumed behaviour, it is necessary to go beyond verbal accounts to document the fluidity of everyday reality.


Assuntos
Homossexualidade Masculina/psicologia , Trabalho Sexual/psicologia , Transexualidade/psicologia , Sexo sem Proteção/psicologia , Humanos , Masculino , Paquistão , Grupo Associado , Estereotipagem
3.
Cochrane Database Syst Rev ; (4): CD003600, 2006 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-17054179

RESUMO

BACKGROUND: Injury in the home is extremely common, accounting for around a third of all injuries. The majority of injuries of children under five and people aged 75 and over, occur at home. Multifactorial injury prevention interventions have been shown to reduce injuries in the home. However, few studies have focused specifically on the impact of physical adaptations to the home environment and the effectiveness of such interventions needs to be ascertained. OBJECTIVES: To review the evidence for the effect on injuries of modification of the home environment with a primary focus on interventions to reduce physical hazards. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE, National Research Register and other specialised databases. We also scanned conference proceedings and reference lists. In addition, we contacted experts and trialists in the field. The searches were not restricted by language or publication status. The searches were last updated in December 2004. SELECTION CRITERIA: Randomised controlled trials. DATA COLLECTION AND ANALYSIS: All abstracts were screened by two authors for relevance, outcome and design. Two authors independently assessed methodological quality and extracted data from each eligible study. MAIN RESULTS: We found 18 published and one unpublished trials. Trials were not sufficiently similar to allow pooling of data by statistical analyses, so this review takes a narrative form. Studies were divided into three groups based on the primary population sample; children (five studies), older people (14 studies) and the general population/mixed age group (no studies). None of the studies focusing on children demonstrated a reduction in injuries that might have been due to environmental adaptation in the home; one study reported a reduction in injuries and in hazards but the two could not be linked. Of the 14 included studies in older people, none demonstrated a reduction in injuries due to hazard reduction, although two demonstrated a reduction in falls that could be due to hazard reduction. AUTHORS' CONCLUSIONS: There is insufficient evidence to determine the effects of interventions to modify environmental home hazards. Further interventions to reduce hazards in the home should be evaluated by adequately designed randomised controlled trials measuring injury outcomes. Recruitment of large study samples to measure effect must be a major consideration for future trials.


Assuntos
Acidentes Domésticos/prevenção & controle , Habitação , Ferimentos e Lesões/prevenção & controle , Idoso , Criança , Ensaios Clínicos Controlados como Assunto , Humanos , Decoração de Interiores e Mobiliário , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Mol Plant Microbe Interact ; 13(6): 617-28, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10830261

RESUMO

We examined the timing and location of several early root responses to Rhizobium leguminosarum bv. trifolii infection, compared with a localized addition of cytokinin in white clover, to study the role of cytokinin in early signaling during nodule initiation. Induction of ENOD40 expression by either rhizobia or cytokinin was similar in timing and location and occurred in nodule progenitor cells in the inner cortex. Inoculation of rhizobia in the mature root failed to induce ENOD40 expression and cortical cell divisions (ccd). Nitrate addition at levels repressing nodule formation inhibited ENOD40 induction by rhizobia but not by cytokinin. ENOD40 expression was not induced by auxin, an auxin transport inhibitor, or an ethylene precursor. In contrast to rhizobia, cytokinin addition was not sufficient to induce a modulation of the auxin flow, the induction of specific chalcone synthase genes, and the accumulation of fluorescent compounds associated with nodule initiation. However, cytokinin addition was sufficient for the localized induction of auxin-induced GH3 gene expression and the initiation of ccd. Our results suggest that rhizobia induce cytokinin-mediated events in parallel to changes in auxin-related responses during nodule initiation and support a role of ENOD40 in regulating ccd. We propose a model for the interactions of cytokinin with auxin, ENOD40, flavonoids, and nitrate during nodulation.


Assuntos
Citocininas/fisiologia , Proteínas de Plantas/biossíntese , Raízes de Plantas/metabolismo , Plantas/metabolismo , Rhizobium leguminosarum/metabolismo , Divisão Celular , Citocininas/farmacologia , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Regulação da Expressão Gênica de Plantas , Genes Reporter , Glucuronidase/metabolismo , Hibridização In Situ , Ácidos Indolacéticos/farmacologia , Fixação de Nitrogênio/genética , Fixação de Nitrogênio/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Raízes de Plantas/microbiologia , Plantas/genética , Plantas/microbiologia , RNA Longo não Codificante , RNA não Traduzido/metabolismo , Simbiose
5.
Mol Plant Microbe Interact ; 13(2): 170-82, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10659707

RESUMO

We examined a range of responses of root cortical cells to Rhizobium sp. inoculation to investigate why rhizobia preferentially nodulate legume roots in the zone of emerging root hairs, but generally fail to nodulate the mature root. We tested whether the inability to form nodules in the mature root is due to a lack of plant flavonoids to induce the bacterial genes required for nodulation or a failure of mature cortical cells to respond to Rhizobium spp. When rhizobia were inoculated in the zone of emerging root hairs, changes in beta-glucuronidase (GUS) expression from an auxin-responsive promoter (GH3), expression from three chalcone synthase promoters, and the accumulation of specific flavonoid compounds occurred in cortical cells prior to nodule formation. Rhizobia failed to induce these responses when inoculated in the mature root, even when co-inoculated with nod gene-inducing flavonoids. However, mature root hairs remained responsive to rhizobia and could support infection thread formation. This suggests that a deficiency in signal transduction is the reason for nodulation failure in the mature root. However, nodules could be initiated in the mature root at sites of lateral root emergence. A comparison between lateral root and nodule formation showed that similar patterns of GH3:gusA expression, chalcone synthase gene expression, and accumulation of a particular flavonoid compound occurred in the cortical cells involved in both processes. The results suggest that rhizobia can "hijack" cortical cells next to lateral root emergence sites because some of the early responses required for nodule formation have already been activated by the plant in those cells.


Assuntos
Fabaceae/microbiologia , Plantas Medicinais , Rhizobium/fisiologia , Citocininas/farmacologia , Fabaceae/genética , Fabaceae/crescimento & desenvolvimento , Flavonoides/metabolismo , Expressão Gênica , Genes de Plantas , Glucuronidase/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas , Simbiose
6.
Mol Plant Microbe Interact ; 10(4): 506-16, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9150598

RESUMO

Proteome analysis was used to establish the first two-dimensional protein map of Rhizobium. R. leguminosarum bv. trifolii strain ANU843 was grown in defined medium in the presence and absence of the flavonoid 7,4'-dihydroxyflavone. Over 1,700 constitutive proteins were resolved, representing about 30% of the estimated genomic output. Proteome analysis of flavonoid-treated cells was done to reveal differentially displayed proteins. The results showed that while the global expression pattern of proteins was largely unaltered by the treatment, four inducible proteins were observed. The four inducible proteins and 20 constitutively expressed proteins were subjected to sequence analysis to provide internal standards for the construction of a two-dimensional Rhizobium protein data base. The identity of 12 proteins, including NodE and NodB, was established. NodE was present throughout the growth of the cells but was diminished in amount in stationary phase cells whereas NodB was not detected in the later stages of growth. Two of the induced proteins sequenced did not match any known nodulation gene product, with one of these being present in mid-late log and stationary phase cells and possessing four consecutive His residues at the N-terminal sequencing was successful with 100 to 200 fmol of protein. Proteome analysis provides a sensitive new tool to examine plant-microbe interactions.


Assuntos
Proteínas de Bactérias/análise , Eletroforese em Gel Bidimensional/métodos , Flavonoides/farmacologia , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana , Rhizobium leguminosarum/química , Aciltransferases/biossíntese , Sequência de Aminoácidos , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Processamento de Imagem Assistida por Computador , Dados de Sequência Molecular , Rhizobium leguminosarum/efeitos dos fármacos , Rhizobium leguminosarum/genética , Análise de Sequência , Homologia de Sequência de Aminoácidos
7.
Mol Plant Microbe Interact ; 7(4): 498-507, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8075422

RESUMO

The gene or genes encoding chalcone synthase (CHS) in the legume Trifolium subterraneum (subterranean clover) were induced within 6 hr after inoculation with Rhizobium leguminosarum bv. trifolii strain ANU843. No induction was found in uninoculated controls or plants inoculated with either the nodulation-deficient R. l. bv. trifolii strain ANU845 (pSym-) or R. meliloti strain 1021, which is capable of nodulating alfalfa but not clover. Morphological examination of the interaction between the legume and bacteria in this system showed that root hair distortion (a marker of the early events in the interaction) was apparent within 10 hr after inoculation. This indicated that CHS induction could occur before any detectable sign of rhizobial penetration of root hairs. The addition of a crude preparation of R. l. bv. trifolii lipooligosaccharide signals (Nod metabolites) to the plant growth medium had no effect on the expression of CHS over 36 hr, although root hair distortion was apparent over this time. These treatments were then contrasted with physical wounding. Wounding the plants led to a rapid induction of CHS, occurring within 2 hr. Sequence analysis of cloned CHS cDNA from pools sampled after Rhizobium inoculation or wounding treatments showed the gene designated CHS5 was the major CHS species in both treatments. Conserved sequences were found in promoters of CHS5 and soybean Gmchs7, a gene which has overlapping expression patterns. These findings support the view that the induction of the phenylpropanoid pathway is involved in the very early events of the Rhizobium infection of legumes.


Assuntos
Aciltransferases/biossíntese , Fabaceae/enzimologia , Fabaceae/microbiologia , Plantas Medicinais , Rhizobium leguminosarum/crescimento & desenvolvimento , Sequência de Bases , Indução Enzimática/efeitos dos fármacos , Fabaceae/efeitos dos fármacos , Fabaceae/fisiologia , Lipopolissacarídeos/farmacologia , Dados de Sequência Molecular , Família Multigênica
8.
Mol Plant Microbe Interact ; 2(3): 97-106, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2520822

RESUMO

The positive activation of several nodulation genes in strain ANU843 of Rhizobium leguminosarum biovar trifolii is mediated by the product of the nodD gene and by the interaction of NodD with plant-secreted inducer and anti-inducer compounds. We have mutagenized the nodD gene of strain ANU843 with nitrosoguanidine and have found that the ability of the mutated nodD products to interact with inducer and anti-inducer compounds is affected by the amino acid sequence in at least two key regions, including a novel area between amino acids 77 and 123. Several novel classes of mutants were recognized by phenotypic and molecular analysis of the mutant nodD genes. Classes 1 and 4 mutants were able to induce nodA expression independently of the addition of inducer and anti-inducer compounds and were unable to mediate autoregulation of the nodD gene. Classes 2 and 3 mutants retained several properties of the wild-type nodD, including the ability to interact with inducer and anti-inducer compounds and the capacity to autoregulate nodD expression. In addition, class 2 mutants showed an inducer-independent ability to mediate nodA expression to 10-fold higher levels over control strains. The class 3 mutant showed reactivity to compounds that had little or no inducing ability with the wild-type nodD. An alteration in NodD function was demonstrated with classes 2 and 3 mutants, which showed greatly enhanced ability to complement a Tn5-induced mutation in the nodD1 gene of strain NGR234 and to restore nodulation ability on the tropical legume siratro. Mutants of nodD possessing inducer-independent ability to activate nod gene expression (classes 1, 2, and 4) were capable of extending the host range of R. l. bv. trifolii to the nonlegume Parasponia. DNA sequence analysis showed that single base changes were responsible for the altered phenotypic properties of five of six mutants examined. Four of the six mutations affected amino acid residues in a putative receiver domain in the N-terminal end of the nodD protein.


Assuntos
Proteínas de Bactérias/genética , Fabaceae/microbiologia , Mutação , Plantas Medicinais , Rhizobium leguminosarum/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Fabaceae/ultraestrutura , Flavonoides/metabolismo , Regulação Bacteriana da Expressão Gênica , Teste de Complementação Genética , Microscopia Eletrônica , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fenótipo , Plasmídeos , Rhizobium leguminosarum/metabolismo , Rhizobium leguminosarum/fisiologia , Alinhamento de Sequência , Fatores de Transcrição/metabolismo
9.
Mol Plant Microbe Interact ; 1(4): 161-8, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2980201

RESUMO

Transfer of the strain NGR234nodD 1 gene into the narrow host range R. trifolii strain ANU843 on either a 6.7-kb HindIII or 17-kb XhoI fragment broadens the host range of this bacterium to include the tropical legumes Vigna unguiculata, Glycine ussuriensis, Leucaena leucocephala, and siratro (Macroptilium atropurpureum). Contrary to previous data (Bassam et al. 1986), mutagenesis of the 17-kb XhoI fragment with a mini-Mu lac transposon (Mu dII1734) showed that a functional nodD 1 gene was essential for extended host range. Gene expression studies using both Mu dII1734 fusions and a promoter-cloning vector indicated that several loci, including the nodD 1 gene, are constitutively expressed. No evidence was found for regulation of the strain NGR234 nodD 1 gene by its product. Another locus nod-81, was induced only in the presence of exudates from various plant species, including soybean (Glycine max). Whereas the expression of nod-81 was dependent on the presence of a functional nodD 1 gene product, a regulatory nod-box DNA sequence was not detected 5' to this gene by using available oligonucleotide hybridization probes. The nod-81 locus was induced by genistein, daidzein, naringenin, and coumestrol from both cotyledon and root tissue of freshly germinated soybean seedlings. A broad spectrum of commercially available phenolic compounds stimulated induction of the nod-81 locus, including some that antagonize nod gene induction in other Rhizobium species. The nodD 1 gene product from strain NGR234 was shown to determine the spectrum of compounds that induce nod-81 expression.


Assuntos
Fabaceae/fisiologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos/genética , Fenóis/farmacologia , Plantas Medicinais , Rhizobium/genética , Sequência de Bases , Clonagem Molecular , Flavonoides/farmacologia , Dados de Sequência Molecular , Mutagênese Insercional , Simbiose/fisiologia , Ativação Transcricional
10.
Mol Plant Microbe Interact ; 12(3): 252-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10065561

RESUMO

We have analyzed the nucleotide sequences of the nodX genes from two strains of Rhizobium leguminosarum bv. viciae able to nodulate Afghan peas (strains A1 and Himalaya) and from two strains of R. leguminosarum bv. trifolii (ANU843 and CSF). The nodX genes of strains A1 and ANU843 were shown to be functional for the induction of nodules on Afghan peas. To analyze the cause of phenotypic differences of strain A1 and strain TOM we have studied the composition of the lipochitin-oligosaccharides (LCOs) produced by strain A1 after induction by the flavonoid naringenin or various pea root exudates. The structural analysis of the LCOs by mass spectrometry revealed that strain A1 synthesizes a family of at least 23 different LCOs. The use of exudates instead of naringenin resulted only in quantitative differences in the ratios of various LCOs produced.


Assuntos
Proteínas de Bactérias/genética , Genes Bacterianos , Rhizobium leguminosarum/genética , Sequência de Aminoácidos , Proteínas de Bactérias/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
11.
Gene ; 138(1-2): 79-86, 1994 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-8125320

RESUMO

Chalcone synthase (CHS) catalyzes the first and key regulatory step in flavonoid biosynthesis. We report the existence and characterization of a CHS multigene family present in Trifolium subterraneum L. cultivar Karridale. The CHS family consists of at least four members, which are tightly clustered in a 15-kb region. The complete sequences of two of these genes (CHS1 and CHS2) are presented. The putative promoters of these genes have sequences which are homologous to those known, or implicated, in regulation of the expression of phenylpropanoid-encoding genes.


Assuntos
Aciltransferases/genética , Sequência Consenso , Fabaceae/enzimologia , Fabaceae/genética , Genes de Plantas , Família Multigênica , Plantas Medicinais , Plantas/genética , Regiões Promotoras Genéticas , Aciltransferases/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Plantas/enzimologia , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
12.
Atherosclerosis ; 149(1): 99-110, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10704620

RESUMO

Atherosclerosis is an inflammatory disease characterised by increased expression of adhesion molecules for leukocytes on both the surface of dysfunctional endothelium and on smooth muscle cells (SMC) within the lesion. It is also characterised by altered SMC phenotypic expression, indicated by a decreased volume fraction of myofilaments (V(v)myo) [1,2] and changes in gene expression [3]. The present study used an in vitro model to investigate, by immunofluorescence staining and flow cytometry, the influence of phenotype on vascular SMC expression of the adhesion molecule for leukocytes, intracellular adhesion molecule-1 (ICAM-1), and the regulatory mechanisms involved in this process. Smooth muscle cells with a high V(v)myo, freshly isolated from rat aortic media, expressed little or no ICAM-1 and this could not be induced by interleukin-1beta (IL-1beta). As SMC modulated phenotype, indicated by decreasing V(v)myo over the first 5 days of culture, there was a concomitant increase in ICAM-1 expression. At day 9 of primary culture, when SMC cultures had returned to the high V(v)myo phenotype, ICAM-1 expression was markedly lower. However, these cells retained the capacity to express ICAM-1 in response to IL-1beta. After several passages in culture, cells (with a low V(v)myo) constitutively expressed ICAM-1, with levels further up-regulated in response to IL-1beta. These changes in ICAM-1 expression were not related to proliferative state, since similar results were obtained with growth arrested SMC. Investigation of signalling pathways involved in regulating ICAM-1 expression by primary vascular SMC suggested a complex regulatory mechanism. Activation of adenyl cyclase (with forskolin) caused a significant increase in cells expressing ICAM-1. Treatment with inhibitors of protein kinase C (chelerythrine chloride), protein tyrosine kinase (genistein), or the transcription factor NF-kappaB (PDTC) had no significant effect on IL-1-induced ICAM-1 expression. However, in the presence of serum, both genistein and PDTC caused a significant increase in basal expression. The results indicate that ICAM-1 expression by SMC is phenotype-dependent, with expression evident only after cells have modulated to a low V(v)myo phenotype. They also indicate the existence of complex regulatory mechanisms, possibly involving the SMC cytoskeleton.


Assuntos
Expressão Gênica , Molécula 1 de Adesão Intercelular/genética , Músculo Liso Vascular/ultraestrutura , Análise de Variância , Animais , Aorta Torácica/citologia , Aorta Torácica/ultraestrutura , Células Cultivadas , Feminino , Citometria de Fluxo , Molécula 1 de Adesão Intercelular/análise , Microscopia de Fluorescência , Músculo Liso Vascular/citologia , Fenótipo , Probabilidade , Ratos , Ratos Wistar , Valores de Referência
13.
Atherosclerosis ; 140(1): 97-104, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9733220

RESUMO

To investigate the growth-regulating action of estrogen on vascular smooth muscle cells (SMC), effects of beta-17-estradiol (beta-E2) on phenotypic modulation and proliferation of rabbit aortic SMC were observed in vitro. At 10(-8)M, beta-E2 significantly slowed the decrease in volume fraction of myofilaments (Vv myo) of freshly dispersed SMCs in primary culture, indicating an inhibitory effect of beta-E2 on spontaneous phenotypic modulation of SMC from a contractile to a synthetic phenotype. Freshly dispersed SMCs treated with beta-E2 also had a relatively longer quiescent phase than control cells before intense proliferation occurred. This was in contrast to SMCs in passage 2 3 (synthetic state), where beta-E2-treated cells replicated significantly faster than untreated cells. beta-E2 also markedly enhanced the serum-induced DNA synthesis of synthetic SMCs in a concentration-dependent manner within physiological range (10(-10)to 10(-8)M). These findings indicate that the growth-regulating effect of estrogen on vascular SMC is dependent on the cell's phenotypic state. It delays the cell cycle re-entry of the contractile SMCs by retarding their phenotypic modulation: however, once cells have modulated to the synthetic phenotype, it promotes their replication.


Assuntos
Estradiol/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Ciclo Celular , Divisão Celular , Replicação do DNA , Feminino , Contração Muscular , Músculo Liso Vascular/metabolismo , Fenótipo , Coelhos , Timidina/metabolismo
14.
J Immunol Methods ; 70(1): 1-11, 1984 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-6715892

RESUMO

The rosette inhibition test has been modified so that early pregnancy factor (EPF) in human pregnancy serum can be detected with mouse lymphocytes. Interference with the assay, which would result from incubation of lymphocytes with heterologous serum proteins, is prevented by the introduction of an ion exchange chromatography step. This provides a simple and rapid method for separating EPF from interfering serum proteins. Human pregnancy and non-pregnancy sera were assayed for EPF with human lymphocytes and results compared with those obtained with DEAE-Sephacel fractions of the same sera tested with mouse lymphocytes. The 2 systems showed good agreement but the mouse assay gave greater differentiation between positive and negative results. When monoclonal anti-T cell antibodies, Hu Ly-m1 and anti-Ly-1.1, were substituted for anti-lymphocyte sera in the human and mouse assay systems respectively, similar results were obtained. The mouse assay system has several advantages over the human assay, including stability of the anti-mouse lymphocyte serum and the ready availability of mouse lymphocytes. Moreover the modified method may be applied not only to the assay of human EPF, but also to the assay of EPF from other species. This would be of value if several species were being studied in 1 laboratory, or if sufficient quantities of lymphocytes from a particular species were not available.


Assuntos
Tolerância Imunológica , Imunossupressores/sangue , Linfócitos/imunologia , Peptídeos , Proteínas da Gravidez , Gravidez , Formação de Roseta , Fatores Supressores Imunológicos , Animais , Anticorpos Monoclonais , Soro Antilinfocitário/farmacologia , Chaperonina 10 , Feminino , Humanos , Imunossupressores/fisiologia , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Especificidade da Espécie
15.
Am J Surg Pathol ; 17(4): 400-9, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8494106

RESUMO

Osteogenic melanoma is a rare variant of malignant melanoma; only eight cases have been reported. To characterize this unusual neoplasm further, we present four new cases. Two patients were men and two were women (average age, 56 years; range, 47-78 years). All tumors arose from acral lentiginous melanomas. Three were subungual finger lesions and one was on the sole of the foot. All four had been previously diagnosed as or were suspected to have been primary osseous lesions. The vertical growth components were high-grade, amelanotic sarcomatoid malignancies with abundant osteoid matrix. Two tumors also had chondroblastic differentiation. Cells with epithelioid features, including prominent eosinophilic nucleoli, were discernible in every tumor. Regional lymph node metastases in two cases retained osteocartilaginous differentiation, whereas metastatic cells in another case were purely epithelioid. Tumor cells in every case were immunoreactive for S-100 protein and vimentin, and non-reactive for cytokeratin. Two tumors also expressed HMB-45. Melanosomes were identified ultrastructurally in every tumor. Follow-up information was available on every patient. Three developed regional lymph node metastases and are currently alive and well after 14, 39, and 101 months. The fourth patient died of metastatic uterine carcinoma 20 months postoperatively. The differential diagnosis of osteogenic melanoma includes osteosarcoma as well as atypical fibro-osseous proliferations. Clinico-pathologic features that support a diagnosis of osteogenic melanoma include junctional activity, absence of primary bony involvement, regional nodal metastases, immunoreactivity for S-100 protein and/or HMB-45, lack of cytokeratin reactivity, and ultrastructural identification of melanosomes.


Assuntos
Melanoma/patologia , Ossificação Heterotópica/patologia , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/metabolismo , Metaplasia , Microscopia Eletrônica , Pessoa de Meia-Idade , Invasividade Neoplásica
16.
J Histochem Cytochem ; 48(11): 1441-52, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11036087

RESUMO

We have previously demonstrated that alpha-smooth muscle (alpha-SM) actin is predominantly distributed in the central region and beta-non-muscle (beta-NM) actin in the periphery of cultured rabbit aortic smooth muscle cells (SMCs). To determine whether this reflects a special form of segregation of contractile and cytoskeletal components in SMCs, this study systematically investigated the distribution relationship of structural proteins using high-resolution confocal laser scanning fluorescent microscopy. Not only isoactins but also smooth muscle myosin heavy chain, alpha-actinin, vinculin, and vimentin were heterogeneously distributed in the cultured SMCs. The predominant distribution of beta-NM actin in the cell periphery was associated with densely distributed vinculin plaques and disrupted or striated myosin and alpha-actinin aggregates, which may reflect a process of stress fiber assembly during cell spreading and focal adhesion formation. The high-level labeling of alpha-SM actin in the central portion of stress fibers was related to continuous myosin and punctate alpha-actinin distribution, which may represent the maturation of the fibrillar structures. The findings also suggest that the stress fibers, in which actin and myosin filaments organize into sarcomere-like units with alpha-actinin-rich dense bodies analogous to Z-lines, are the contractile structures of cultured SMCs that link to the network of vimentin-containing intermediate filaments through the dense bodies and dense plaques.


Assuntos
Actinas/metabolismo , Músculo Liso Vascular/metabolismo , Actinina/metabolismo , Animais , Aorta/citologia , Células Cultivadas , Citoesqueleto/metabolismo , Fluorescência , Microscopia Confocal , Contração Muscular , Músculo Liso Vascular/citologia , Cadeias Pesadas de Miosina/metabolismo , Isoformas de Proteínas/metabolismo , Coelhos , Vimentina/metabolismo , Vinculina/metabolismo
17.
J Reprod Immunol ; 4(5): 251-61, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7131430

RESUMO

The rosette inhibition test for the detection of early pregnancy factor is described in detail. The extended methodology presented here represents the cumulative experience of three independent laboratories. Special reference is made to the effect on the assay of varying the conditions of rosette formation between lymphocytes and sheep red blood cells. Antilymphocyte sera prepared for use in the rosette inhibition test fell into three categories: (i) with no rosette inhibiting activity, (ii) with rosette inhibiting activity which is not affected by the presence of EPF, and (iii) rosette inhibiting activity which is significantly increased in the presence of EPF. To date, this third reaction has been found to be a specific indication of the presence in serum of early pregnancy factor.


Assuntos
Imunossupressores/farmacologia , Peptídeos , Proteínas da Gravidez , Formação de Roseta/métodos , Fatores Supressores Imunológicos , Animais , Soro Antilinfocitário/farmacologia , Chaperonina 10 , Feminino , Cabras , Cobaias , Cavalos , Humanos , Linfócitos/imunologia , Masculino , Gravidez , Coelhos
18.
Ann N Y Acad Sci ; 947: 316-22, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11795282

RESUMO

The role of the small GTP-binding protein Rho in the process of smooth muscle cell (SMC) phenotypic modulation was investigated using cultured rabbit aortic SMCs. Both Rho transcription and Rho protein expression were high for the first 3 days of culture ("contractile" state cells), with expression decreasing after change to the "synthetic" state and peaking upon return to the contractile phenotype. Activation of Rho (indicated by translocation to the membrane) also peaked upon return to the contractile state and was low in synthetic state SMCs. Transient transfection of synthetic state rabbit SMCs with constitutively active Rho (vall4rho) caused a dramatic decrease in cell size and reorganization of cytoskeletal proteins to resemble those of the contractile phenotype; alpha-actin and myosin adopted a tightly packed, highly organized arrangement, whereas vimentin localized to the immediate perinuclear region and focal adhesions were enlarged. Conversely, specific inhibition of endogenous Rho, by expression of C3 transferase, resulted in the complete loss of actin and myosin filaments without affecting the distribution of vimentin. Focal adhesions were reduced in number. Thus, Rho plays a key role in regulating SMC phenotypic expression.


Assuntos
Músculo Liso Vascular/fisiologia , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Células Cultivadas , Regulação da Expressão Gênica , Fenótipo , Transporte Proteico , Coelhos
19.
Ann N Y Acad Sci ; 947: 323-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11795283

RESUMO

Previous studies in our laboratory have shown that the pleiotropic cytokine leukemia inhibitory factor (LIF) inhibits neointimal formation and the development and progression of atherosclerotic and restenotic lesions in a rabbit model of disease. The present study demonstrates an upregulation of both the LIF receptor (LIFR)-alpha subunit and the signal transducing subunit gp130 following endothelial denudation of the carotid artery by balloon catheter. Continuous infusion of LIF (30 microg/kg/day) resulted in the downregulation of LIFR-alpha in injured arteries in vivo. Similarly, smooth muscle cells in vitro treated with LIF exhibited a time-dependent reduction in LIFR-alpha protein expression and the subsequent reduction in transcription of the TIMP-1 gene. However, in the presence of an intact endothelium, LIFR-alpha was upregulated in response to LIF, and accordingly the downstream induction of iNOS expression was also increased. Thus, LIF exerts more potent antiatherogenic effects in the vasculature when the endothelium is intact.


Assuntos
Regulação da Expressão Gênica , Chaperonas Moleculares/farmacologia , Músculo Liso Vascular/fisiologia , Proteínas , Receptores de Citocinas/genética , Animais , Células Cultivadas , Regulação para Baixo , Interleucina-6 , Fator Inibidor de Leucemia , Receptores de OSM-LIF , Transdução de Sinais , Regulação para Cima
20.
Fertil Steril ; 37(5): 655-60, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-6176474

RESUMO

Production of the pregnancy-specific protein early pregnancy factor (EPF) was monitored by the rosette inhibition test in a group of 13 nulliparous women. EPF could be detected in serum within 48 hours of fertilization; of 28 cycles in which intercourse took place at the time of ovulation, EPF was detected in 18. However, EPF production continued for more than 14 days in only four cases. Successful pregnancy was maintained in two of these while in the other two, disappearance of EPF preceded miscarriage. In the remaining 14 cases, EPF disappeared from the serum before the onset of menstruation. A high incidence of early embryonic loss is suggested.


Assuntos
Morte Fetal/diagnóstico , Imunossupressores/sangue , Peptídeos , Proteínas da Gravidez , Fatores Supressores Imunológicos , Animais , Chaperonina 10 , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica Humana Subunidade beta , Implantação do Embrião , Feminino , Cabras/imunologia , Humanos , Masculino , Fragmentos de Peptídeos/sangue , Gravidez , Progesterona/sangue , Formação de Roseta
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