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1.
Health Commun ; 36(4): 521-528, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31818138

RESUMO

Information gleaned from a patients' medical history is a core determinant of a medical diagnosis. Accurate and effective history-taking is, therefore, a foundational skill for medical practitioners and is introduced early in medical training. Recognizing and developing the skills of effective medical interviewing is an ongoing challenge for medical students and experienced clinicians alike. Important parallels exist between the information gathering skills required in medicine and health, and those required in investigative interviewing. Qualitative interviews were conducted with 19 experienced medical professionals from a range of specialty areas. They were asked about the role of the medical interview in their discipline, and about challenges they experience when gathering information from patients. Both theory-driven and grounded-theory approaches were used in combination to identify common themes. The interviews were rich with themes including approaches to introductory phases of the interview, eliciting a narrative account, and several topics that specifically paralleled issues in interviewing of vulnerable witnesses. We explore these themes through a lens of investigative interviewing by applying the knowledge of effective interviewing skills and structures to the data gained from the medical context. In general, themes indicated that there are numerous parallels to information gathering approaches in both contexts. As such, there may be scope for medical education to adopt some of the training techniques employed in the investigative interviewing field. Further, it is hoped that the present findings be used to spark an interdisciplinary conversation about communication from which both sides can learn.


Assuntos
Educação Médica , Estudantes de Medicina , Comunicação , Pessoal de Saúde , Humanos
2.
J Perinatol ; 37(1): 88-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27684421

RESUMO

OBJECTIVE: To define the impact of care standardization on caffeine and cardiorespiratory monitoring at neonatal intensive care unit (NICU) discharge. STUDY DESIGN: Electronic records were abstracted for infants aged 24-36 weeks gestation with birth weights appropriate for gestational age. Infants who died, transferred prior to discharge, had major pulmonary anomalies, required a home monitor for mechanical ventilation or had a family history of sudden infant death syndrome were excluded. Data and records were used to indicate when the new definition of clinically significant cardiopulmonary events (CSCPEs) and concurrent education was implemented. Preimplementation and postimplementation cohorts were compared. RESULTS: Incidence fell from 74% diagnosed with apnea of prematurity at baseline to 49% diagnosed with CSCPE postimplementation (P<0.001). Infants discharged on caffeine reduced from 17% to 5% (P<0.001), and home monitor use also fell from 54% to 16% (P<0.001). CONCLUSION: Standardizing definitions and treatments reduced the use of caffeine and cardiorespiratory monitors upon NICU dismissal.


Assuntos
Apneia/diagnóstico , Apneia/terapia , Cafeína/uso terapêutico , Recém-Nascido de Baixo Peso , Recém-Nascido Prematuro , Monitorização Fisiológica , Peso ao Nascer , Gerenciamento Clínico , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Masculino , Respiração Artificial/métodos , Estudos Retrospectivos , Estados Unidos
3.
Oncogene ; 33(9): 1093-100, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23435419

RESUMO

Metastatic melanoma remains a devastating disease with a 5-year survival rate of less than five percent. Despite recent advances in targeted therapies for melanoma, only a small percentage of melanoma patients experience durable remissions. Therefore, it is critical to identify new therapies for the treatment of advanced melanoma. Here, we define connective tissue growth factor (CTGF) as a therapeutic target for metastatic melanoma. Clinically, CTGF expression correlates with tumor progression and is strongly induced by hypoxia through HIF-1 and HIF-2-dependent mechanisms. Genetic inhibition of CTGF in human melanoma cells is sufficient to significantly reduce orthotopic tumor growth, as well as metastatic tumor growth in the lung of severe combined immunodeficient (SCID) mice. Mechanistically, inhibition of CTGF decreased invasion and migration associated with reduced matrix metalloproteinase-9 expression. Most importantly, the anti-CTGF antibody, FG-3019, had a profound inhibitory effect on the progression of established metastatic melanoma. These results offer the first preclinical validation of anti-CTGF therapy for the treatment of advanced melanoma and underscore the importance of tumor hypoxia in melanoma progression.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Fator de Crescimento do Tecido Conjuntivo/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Hipóxia/genética , Fator 1 Induzível por Hipóxia/genética , Metaloproteinase 9 da Matriz/genética , Melanoma/patologia , Camundongos , Camundongos SCID
4.
J Leukoc Biol ; 69(1): 161-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11200061

RESUMO

The exposure to epigenetic effectors capable of inducing copious production of reactive oxygen species (ROS) has been associated with chronic inflammation, tumor initiation, and promotion. The objective of this study was to examine the regulation of gp91phox, the catalytic subunit of the NADPH oxidase, and the kinetics of ROS production in promyelocytic leukemia HL-60 cells induced with 12-O-tetradeconylphorbol-13-acetate (TPA). The treatment of HL-60 cells with TPA (0.1 microM) induced cellular differentiation, which was followed after 48 h by a tenfold increase in chemiluminescence from lucigenin and a 2.5-fold increase in the intracellular oxidation of 2',7'-dicholorofluorescin (DCFH). Whereas higher concentrations (1.0 microM) of TPA did not stimulate further ROS production, repeated stimulation with 0.1 microM TPA of differentiated cells induced a modest (1.2-fold) but rapid (15 min) increase in chemiluminescence. In cells treated with TPA, the burst in ROS at 48 h was preceded by accumulation at 12 h of gp91phox (8.8-fold) and p47phox mRNA (threefold), whereas untreated cells contained steady-state levels of both transcripts. Time-course experiments with actinomycin D to inhibit transcription revealed that TPA did not improve the stability of gp91phox. In transient transfections, luciferase reporter activity directed from a 1.5-kb gp91phox promoter fragment was enhanced threefold upon treatment with TPA for 24 h. We conclude that TPA can commit HL-60 cells to differentiation and elicit transcription from the proximal gp91phox promoter.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glicoproteínas de Membrana/genética , Forbóis/farmacologia , Ativação Transcricional/efeitos dos fármacos , Células HL-60 , Humanos , NADPH Oxidase 2 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo
5.
Child Abuse Negl ; 25(12): 1643-59, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11814161

RESUMO

OBJECTIVE: For successful prosecution of child sexual abuse, children are often required to provide reports about individual, alleged incidents. Although verbally or mentally rehearsing memory of an incident can strengthen memories, children's report of individual incidents can also be contaminated when they experience other events related to the individual incidents (e.g., informal interviews, dreams of the incident) and/or when they have similar, repeated experiences of an incident, as in cases of multiple abuse. METHOD: Research is reviewed on the positive and negative effects of these related experiences on the length, accuracy, and structure of children's reports of a particular incident. RESULTS: Children's memories of a particular incident can be strengthened when exposed to information that does not contradict what they have experienced, thus promoting accurate recall and resistance to false, suggestive influences. When the encountered information differs from children's experiences of the target incident, however, children can become confused between their experiences-they may remember the content but not the source of their experiences. CONCLUSIONS: We discuss the implications of this research for interviewing children in sexual abuse investigations and provide a set of research-based recommendations for investigative interviewers.


Assuntos
Maus-Tratos Infantis/psicologia , Psiquiatria Legal/normas , Entrevista Psicológica , Anedotas como Assunto , Criança , Confusão , Psiquiatria Legal/métodos , Humanos , Rememoração Mental , Autorrevelação , Sugestão
6.
Cytogenet Cell Genet ; 89(3-4): 264-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10965140

RESUMO

The gene encoding the mouse analogue of the human complement regulator CD59 was cloned using a combination of long range PCR and genomic library screening. Sequence obtained showed that its genomic structure closely resembled that of the human CD59 gene, comprising 4 exons, each separated by a long intron region. The sizes of introns and exons were comparable to those of the human gene with the exception of the third intron which is 2.5 kb in the mouse compared to 7 kb in the human gene. All exon/intron boundaries conformed to the GT-AG rules for splicing. Radiation hybrid mapping localised mouse Cd59 between D2Mit333 and D2Mit127 on chromosome 2, a region homologous with human chromosome 11p13 where the human CD59 gene is localised. These data have permitted the construction of a gene targeting vector for the generation of transgenic mice deficient in CD59.


Assuntos
Antígenos CD59/genética , Genes/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , DNA/química , DNA/genética , Éxons , Células Híbridas , Íntrons , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Análise de Sequência de DNA
7.
Science ; 287(5455): 1031, 2000 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-10669413

RESUMO

The nonclassical major histocompatibility complex (MHC) class I molecule HLA-E inhibits natural killer (NK) cell-mediated lysis by interacting with CD94/NKG2A receptors. Surface expression of HLA-E depends on binding of conserved peptides derived from MHC class I molecules. The same peptide is present in the leader sequence of the human cytomegalovirus (HCMV) glycoprotein UL40 (gpUL40). It is shown that, independently of the transporter associated with antigen processing, gpUL40 can up-regulate expression of HLA-E, which protects targets from NK cell lysis. While classical MHC class I molecules are down-regulated, HLA-E is up-regulated by HCMV. Induction of HLA-E surface expression by gpUL40 may represent an escape route for HCMV.


Assuntos
Antígenos CD , Citomegalovirus/metabolismo , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/imunologia , Sinais Direcionadores de Proteínas/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Linhagem Celular , Membrana Celular/imunologia , Células Cultivadas , Sequência Conservada , Citomegalovirus/genética , Citomegalovirus/imunologia , Citotoxicidade Imunológica , Regulação para Baixo , Antígenos HLA/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Dados de Sequência Molecular , Fases de Leitura Aberta , Sinais Direcionadores de Proteínas/química , Receptores Imunológicos/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , Regulação para Cima , Proteínas Virais/química , Proteínas Virais/genética , Antígenos HLA-E
8.
Dev Psychol ; 35(6): 1462-77, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10563735

RESUMO

The effect of suggestive questions on 3- to 5-year-old and 6- to 8-year-old children's recall of the final occurrence of a repeated event was examined. The event included fixed (identical) items as well as variable items where a new instantiation represented the item in each occurrence of the series. Relative to reports of children who participated in a single occurrence, children's reports about fixed items of the repeated event were more accurate and less contaminated by false suggestions. For variable items, repeated experience led to a decline in memory of the specific occurrence; however, there was no increase in susceptibility to suggestions about details that had not occurred. Most errors after repeated experience were intrusions of details from nontarget occurrences. Although younger children and children who were interviewed a while after the event were more suggestible, respectively, than older children and those interviewed soon after the event, repeated experience attenuated these effects.


Assuntos
Cognição/fisiologia , Sugestão , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Rememoração Mental/fisiologia , Periodicidade , Psicologia da Criança , Distribuição Aleatória
9.
Carcinogenesis ; 20(9): 1709-13, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10469614

RESUMO

The colorectal mucosa of pre-symptomatic individuals with familial adenomatous polyposis (FAP) contains elevated levels of the proliferation-associated polyamines. The Min mouse, like humans with FAP, expresses an abnormal genotype for the APC tumor suppressor gene. In order to determine how APC mutation influences intestinal tissue polyamine content, we measured steady-state RNA levels of ornithine decarboxylase (ODC), the first enzyme in polyamine synthesis, antizyme (AZ), a protein which negatively regulates ODC, and the spermidine/spermine N(1)-acetyltransferase (SSAT), the first enzyme in polyamine catabolism. RNA content was increased 6- to 8-fold in both the small intestine and colon for ODC, decreased significantly in the small intestine but not the colon for AZ and was not statistically different in either intestinal tissue for SSAT in Min mice compared with normal littermates. Consistent with the changes in ODC and AZ gene expression, small intestinal, but not colonic, polyamine content was elevated in Min mice compared with normal littermates. Treatment of Min mice with the specific ODC inhibitor difluoromethylornithine (DFMO) suppressed small intestinal, but not colonic, polyamine content and tumor number. These data indicate that small intestinal tissue polyamine content is elevated in Min mice by a mechanism involving APC-dependent changes in ODC and AZ RNA. Further, ODC enzyme activity, which is influenced by both ODC and AZ RNA levels and inhibited by DFMO, is consequential for small intestinal tumorigenesis in this model. In the FAP population, DFMO may be of value in the chemoprevention of small intestinal adenocarcinoma that remains a risk following colectomy.


Assuntos
Colo/metabolismo , Neoplasias do Colo/genética , Regulação da Expressão Gênica , Genes APC , Neoplasias Intestinais/genética , Intestino Delgado/metabolismo , Ornitina Descarboxilase/biossíntese , Poliaminas/metabolismo , Biossíntese de Proteínas , Acetiltransferases/biossíntese , Acetiltransferases/genética , Animais , Anticarcinógenos/farmacologia , Colo/enzimologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/prevenção & controle , Eflornitina/farmacologia , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/prevenção & controle , Intestino Delgado/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Especificidade de Órgãos , Ornitina Descarboxilase/genética , Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
10.
Br J Ophthalmol ; 82(8): 953-60, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9828784

RESUMO

AIMS/BACKGROUND: The authors have developed transgenic mouse strains at the Arizona Cancer Center using a tyrosinase promoter to target expression of the mutated T24 Ha-ras gene in melanin producing cells. Histopathology and electron microscopy (EM) were performed to characterise the intraocular tumours observed phenotypically. METHODS: Transgenic TPras mice (n = 8) and normal, age matched control mice (n = 6) were sacrificed at 3 weeks, 6 weeks, 7 weeks, 4 months, 5 months, 9 months, and 11 months. Six were processed in formalin for light microscopic examination and eight in a glutaraldehyde/formalin solution for electron microscopic examination. RESULTS: Six of the TPras mice were found to have bilateral pigmented melanocytic/RPE proliferations of the uveal tract. The cytological characteristics of the tumours included low nuclear to cytoplasmic ratios (N:C ratios), bland nuclei, and abundant intracytoplasmic melanin. By EM two populations of cells were identified, including spindle-shaped cells with round to oval melanin granules and cuboidal cells with apically located, cigar-shaped, melanin granules, and basement membrane formation. A 3 week and an 11 month old TPras mouse had a higher grade, bilateral, melanocytic proliferation of the uveal tract which, although not metastatic, was morphologically melanoma. Cytological features included increased N:C ratios, nuclear pleomorphism, and prominent nucleoli. The uveal tract was normal in both eyes in all of the control animals. CONCLUSION: Pigmented intraocular tumours developed in transgenic strains of mice that express a mutated Ha-ras gene in melanin producing cells. The morphology was most consistent with a melanoma in two of the mice and a benign melanocytic/RPE proliferation in the remaining mice.


Assuntos
Melanoma Experimental/ultraestrutura , Neoplasias Uveais/ultraestrutura , Animais , Divisão Celular , Modelos Animais de Doenças , Genes ras , Melanócitos/patologia , Melanoma Experimental/genética , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica , Mutação , Epitélio Pigmentado Ocular/patologia , Neoplasias Uveais/genética
11.
J Biol Chem ; 273(48): 32176-81, 1998 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-9822695

RESUMO

The effects of UVB irradiation on transcription factor activator protein-1 (AP-1) DNA binding and AP-1 transactivation were studied in a human keratinocyte cell line, HaCaT. UVB-induced AP-1 binding to a consensus AP-1 binding site was observed by gel shift assays with maximum stimulation at 12 h after UVB irradiation. A promoter region of the human collagenase-1 gene containing the same AP-1 binding sequence linked to a luciferase reporter gene was stably transfected into HaCaT cells. UVB irradiation significantly increased luciferase activity in these stably transfected cells, with maximum activity observed at 24 h after UVB irradiation. c-Fos and Jun D were identified by antibody clearing assays as the main components of the bound AP-1 complexes. Inhibition of transcription with actinomycin D and inhibition of protein synthesis with cycloheximide significantly abrogated the effect of UVB on AP-1 DNA binding, indicating that transcription and translation were required for AP-1 activation. Northern and Western analyses revealed a correlation between increased AP-1 activity and accumulation of c-fos mRNA and c-Fos protein after UVB irradiation. UVB irradiation increased c-fos transcription in HaCaT cells stably transfected with a plasmid containing the human c-fos promoter driving a luciferase reporter gene. These results suggest that increased c-fos expression may play an important role in UVB-induced AP-1 activation in HaCaT cells.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Genes fos/efeitos da radiação , Queratinócitos/efeitos da radiação , Proteínas Proto-Oncogênicas c-fos/genética , Fator de Transcrição AP-1/efeitos da radiação , Raios Ultravioleta , Linhagem Celular , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Relação Dose-Resposta à Radiação , Genes Reporter , Humanos , Queratinócitos/metabolismo , Cinética , Luciferases/biossíntese , Luciferases/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/efeitos da radiação , Ativação Transcricional/efeitos da radiação
12.
Nutr Cancer ; 31(2): 111-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9770722

RESUMO

Epidemiological studies have suggested that the concentration and composition of fecal bile acids are important determining factors in the etiology of colon cancer. However, the mechanism by which these compounds influence tumor development is not understood. To begin to elucidate their mechanism of action, four bile acids, cholic acid, chenodeoxycholic acid, deoxycholic acid (DCA), and ursodeoxycholic acid, were examined for their effects on the growth of several different tumor cell lines. We found that incubating cells with chenodeoxycholic acid or DCA caused morphological changes, seen by electron and light microscopy, that were characteristic of apoptosis, whereas incubating cells with ursodeoxycholic acid inhibited cell proliferation but did not induce apoptosis. Cholic acid had no discernible effect on cells. Notably, the apoptosis induced by DCA could be suppressed by inhibiting protein kinase C activity with calphostin C. These results indicate that different bile acids exhibit distinct biological activities and suggest that the cytotoxicity reported for DCA may be due to its capacity to induce apoptosis via a protein kinase C-dependent signaling pathway.


Assuntos
Anticarcinógenos/metabolismo , Ácidos e Sais Biliares/metabolismo , Carcinógenos/efeitos adversos , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Ácido Desoxicólico/efeitos adversos , Ácido Ursodesoxicólico/metabolismo , Apoptose , Divisão Celular , Ácido Quenodesoxicólico/metabolismo , Ácido Cólico/metabolismo , Humanos , Células Tumorais Cultivadas/metabolismo
13.
Mol Carcinog ; 20(1): 78-87, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9328438

RESUMO

The TP-ras transgenic mouse line expresses an activated human T24 Ha-ras gene with a mutation in codon 12, regulated by a mouse tyrosinase promoter. The transgene is expressed in melanocytes of the skin, eyes, and brain. The mice develop cutaneous melanoma when treated with 7,12-dimethylbenz[a]anthracene. Cell lines have been generated from the cutaneous tumors and metastatic lesions. By using fluorescence in situ hybridization with mouse whole chromosome paints, the cell lines were characterized for chromosomal abnormalities. Key findings in the tumor cells included translocations of chromosome 4 and alterations in chromosome 6. One tumor cell line contained a double translocation involving chromosomes 3 and 6. To extend the results of the chromosome 4 painting, Southern analysis of the p15INK4B, p16INK4A, and p19INK4D genes was performed. Our data indicated that there were homozygous and partial allelic deletions and polymorphisms in the region of chromosome 4 containing these genes, resulting in the absence or reduced expression of the p16 product. These findings are similar to those reported for human melanoma, and the TP-ras transgenic mouse may therefore be a valuable model for studying novel strategies for melanoma prevention and treatment.


Assuntos
9,10-Dimetil-1,2-benzantraceno , Carcinógenos , Genes ras , Melanoma Experimental/induzido quimicamente , Melanoma Experimental/genética , Animais , Southern Blotting , Western Blotting , Proteínas de Transporte/análise , Proteínas de Transporte/biossíntese , Aberrações Cromossômicas , Cromossomos , Inibidor p16 de Quinase Dependente de Ciclina , Hibridização in Situ Fluorescente , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos
14.
J Immunol ; 158(4): 1692-702, 1997 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9029105

RESUMO

We have previously described the isolation and cloning of the rat analogue of the human complement inhibitor CD59 (hCD59). Using the rat CD59 (rCD59) coding region as probe, we have isolated positive cDNAs from a mouse kidney cDNA library. Sequence analysis of these clones indicated that they contained an open reading frame encoding a 124 amino acid protein. Comparisons with the known sequences of hCD59 and rCD59 suggested that the clones contained a full-length cDNA encoding the mouse analogue of CD59 (mCD59). The cDNA encoded a 81-bp 5'-flanking region, a 23 amino acid NH2-signal peptide, a 101 amino acid coding region including putative N-glycosylation sites and a glycosyl phosphatidylinositol (GPI) anchoring signal, and approximately 0.8 kb 3'-untranslated flanking region. Reverse transcriptase PCR revealed the presence of mCD59 mRNA in all mouse tissues examined. The gene for mCD59 was mapped by fluorescence in situ hybridization to the E2-E4 region of mouse chromosome 2, a region that includes areas syntenous with the location of the human CD59 gene on chromosome 11p13. Expression of mCD59 in a CD59-negative human cell line conferred protection against lysis by complement from rodent, human, and several other species, confirming that mCD59 was the functional analogue of hCD59 and that function was not species restricted. The expressed protein was glycosyl phosphatidylinositol anchored as demonstrated by its partial removal from U937 cells on treatment with phosphatidylinositol-specific phospholipase C. Abs raised against the expressed protein demonstrated the presence of mCD59 on all mouse blood cell types and on several mouse cell lines and neutralized function of mCD59 on mouse E and expressed on U937. Western blot analysis revealed that both expressed and endogenous mCD59 had a molecular mass of 22 to 24 kDa.


Assuntos
Antígenos CD59/genética , Mapeamento Cromossômico , Regulação da Expressão Gênica/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Western Blotting , Antígenos CD59/biossíntese , Antígenos CD59/isolamento & purificação , Antígenos CD59/fisiologia , Clonagem Molecular , Citotoxicidade Imunológica/genética , DNA Complementar/isolamento & purificação , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Ratos
15.
Exp Cell Res ; 231(1): 61-5, 1997 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-9056412

RESUMO

The expression of extracellular-matrix (ECM)-degrading proteases has been shown to be necessary for invasion of tumor cells into surrounding tissue. For several tumor types, overexpression of these proteases is dependent upon interactions with adjacent fibroblast cell populations. We previously demonstrated activation of matrix metalloprotease (MMP) and urokinase-type plasminogen activator (uPa) expression in a coculture model consisting of squamous cell carcinoma cells (SCC) with dermal fibroblasts. In the present study we have examined whether melanocytes, which are known to interact closely with keratinocytes of the basal epidermal layer, might influence ECM-degrading protease expression in SCC cells as well. Upon coculture of the human SCC cell line II-4 with the nontumorigenic mouse melanocyte cell line Melan-a or treatment of II-4 cells with Melan-a conditioned media, induction of expression of the MMP matrilysin and uPa was observed. In contrast, no induction was observed for stromelysin-1 or 92-kDa type IV collagenase. Matrilysin/uPa-inducing activity was found to act at the level of gene transcription for both matrilysin and uPa and was ubiquitously expressed among six different human melanocytic cell strains/lines, ranging from primary normal melanocytes to cell lines established from metastatic melanoma lesions. These data demonstrate that melanocytic cells can exert a paracrine influence in SCC cells on the expression of specific proteases involved in ECM turnover and tumor invasiveness.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Matriz Extracelular/metabolismo , Melanócitos/fisiologia , Metaloendopeptidases/biossíntese , Ativador de Plasminogênio Tipo Uroquinase/biossíntese , Animais , Linhagem Celular , Linhagem Celular Transformada , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados , Indução Enzimática , Humanos , Metaloproteinase 7 da Matriz , Melanócitos/citologia , Melanoma , Metaloendopeptidases/genética , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas , Ativador de Plasminogênio Tipo Uroquinase/genética
16.
Child Dev ; 67(5): 1988-2004, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9022225

RESUMO

Children's memory of the final occurrence of a repeated event was examined whereby each occurrence had the same underlying structure but included unpredictable variations in the specific instantiations of items across the series. The event was administered by the children's teachers at the kindergarten or school. The effects of repetition (single vs. repeated event), age (4-5 vs. 6-8-year-olds), retention interval (1 week vs. 6 weeks), and the frequency of specific instantiations of items were examined across 3 question types. Repetition increased the number of items recalled on a level that was common to all occurrences in response to general probes and reduced the likelihood that children would report details that did not occur in the event. However, repetition also reduced the number of correct responses about which instantiation was included in the occurrence and decreased the consistency of responses across repeated questioning. Most errors were intrusions of details from other occurrences; usually references to instantiations of items that had occurred frequently throughout the series. The younger children showed a poorer ability to discriminate between the occurrences than the older children, but age differences were less evident at the longer retention interval. The results are discussed in relation to current theories of memory and children's eyewitness testimony.


Assuntos
Atenção , Desenvolvimento Infantil , Rememoração Mental , Retenção Psicológica , Aprendizagem Seriada , Aprendizagem por Associação , Criança , Pré-Escolar , Aprendizagem por Discriminação , Feminino , Humanos , Masculino , Resolução de Problemas , Enquadramento Psicológico
17.
Mol Carcinog ; 12(2): 82-90, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7662120

RESUMO

The tyrosinase promoter has been used to target expression of the mutated human T24 Ha-ras oncogene in pigment-producing cells of transgenic mice. Two independent founder mice carrying the transgene survived and showed the same distinct phenotype of mutated coat color, deeply pigmented skin with multiple nevi, and twirling behavior. The offspring of one of these founders were developed into a line that stably expressed the same phenotype. Histopathological analysis of the tissues revealed hyperpigmentation and/or melanocytic hyperplasia in the skin, eyes, inner ear, and meningeal membranes in the brain. Reverse transcriptase-polymerase chain reaction analysis revealed expression of the transgene in skin, brain, and spleen. We propose that these transgenic mice will be a model for studying the process of multistage melanoma carcinogenesis and a system for evaluating potential chemopreventive agents.


Assuntos
Genes ras , Melanócitos/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Sequência de Bases , Primers do DNA/química , Humanos , Hiperplasia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/genética , Pigmentação , Lesões Pré-Cancerosas/patologia , Ratos , Transfecção
18.
Exp Cell Res ; 213(1): 143-7, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8020584

RESUMO

The purpose of this study was to characterize stromal-epithelial interactions that result in induction of protease gene expression in squamous cell carcinoma of the skin. Coculture of the human squamous cell carcinoma cell line II4 with primary human foreskin fibroblasts was observed to induce mRNA expression of urokinase-type plasminogen activator (uPa), matrilysin, 92-kDa type IV collagenase, and c-ets, a transcriptional activator of several genes within the serine and matrix metalloprotease families. uPA and c-ets induction were localized to the fibroblast cell population. uPa induction was found to be dependent upon cell-cell contact with the tumor cell population, whereas c-ets induction was due to a combination of cell-cell contact and a tumor cell-derived soluble factor. In contrast, matrilysin induction localized to the tumor cells and was shown by Northern and Western analyses to occur in response to a fibroblast-derived soluble factor. These data demonstrate that both paracrine factors and cell-cell contact between stromal fibroblasts and epithelial tumor cells can influence protease gene expression.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Comunicação Celular , Endopeptidases/biossíntese , Regulação Neoplásica da Expressão Gênica , Junções Intercelulares/fisiologia , Queratinócitos/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Proto-Oncogenes , Neoplasias Cutâneas/metabolismo , Pele/metabolismo , Fatores de Transcrição , Western Blotting , Células Cultivadas , Colagenases/biossíntese , Colagenases/isolamento & purificação , Indução Enzimática , Fibroblastos/metabolismo , Humanos , Masculino , Metaloproteinase 7 da Matriz , Metaloproteinase 9 da Matriz , Metaloendopeptidases/biossíntese , Metaloendopeptidases/isolamento & purificação , Proteínas Proto-Oncogênicas c-ets , Serina Endopeptidases/biossíntese , Células Tumorais Cultivadas , Ativador de Plasminogênio Tipo Uroquinase/biossíntese
19.
Cancer Res ; 54(4): 882-6, 1994 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8313375

RESUMO

The viral jun (v-jun) oncogene encodes a transcription factor that can participate in the transactivation of genes through the AP-1 complex. Evidence indicates that the ability of v-jun to transform cells and stimulate transcription depends on the cell type. We have asked whether expression of the v-jun gene in benign tumor forming mouse keratinocytes that already express an activated c-rasHa oncogene would cause malignant progression. Our results showed that the v-jun transfection did not result in malignant progression; instead, we made the unexpected observation that the ability of these cells to invade reconstituted basement membrane matrix (in vitro) in response to the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate, was suppressed. This phenomenon could, in part, be explained by the suppression of the induction by phorbol ester of expression of the metalloproteinase, stromelysin (transin). Of interest was the finding that 12-O-tetradecanoylphorbol-13-acetate induction of other cellular genes known to be regulated by AP-1 was not inhibited in the benign tumor cells expressing v-jun.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes jun , Metaloendopeptidases/genética , Invasividade Neoplásica/fisiopatologia , Papiloma/patologia , Acetato de Tetradecanoilforbol/farmacologia , Animais , Metaloproteinase 3 da Matriz , Camundongos , Papiloma/metabolismo , Transfecção , Células Tumorais Cultivadas
20.
J Cancer Res Clin Oncol ; 119(4): 199-206, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7678596

RESUMO

Normal human melanocytes require 12-O-tetradecanoylphorbol 13-acetate (TPA) for prolonged growth in vitro. In contrast, the growth of human malignant melanoma cells is often inhibited by TPA. In this study, we have confirmed and extended these observations. Since protein kinase C (PKC) is an important mediator of the effects of TPA, we have investigated the nature of this differential growth response by examining PKC expression and activity in primary cultures of human neonatal melanocytes and metastatic melanoma cell strains. PKC, when measured by immunoreactivity or a functional assay, was found to be more abundant in melanoma cells than in melanocytes. When specific isotypes were examined by Northern analysis, PKC-alpha and -epsilon were expressed in both melanocytes and melanoma. PKC-beta was expressed in melanocytes, but was undetectable by Northern analysis in 10 out of 11 melanoma cell strains. Southern analysis revealed that no gross deletions or rearrangements of the PKC-beta gene had occurred. These data suggest that down-regulation of the PKC-beta gene occurs frequently during the process of transformation of melanocytes. Furthermore, differential expression of PKC isotypes may explain the different effects of TPA on melanocyte and melanoma cell growth.


Assuntos
Melanócitos/enzimologia , Melanoma/enzimologia , Proteína Quinase C/análise , Acetato de Tetradecanoilforbol/farmacologia , Northern Blotting , Southern Blotting , Divisão Celular/efeitos dos fármacos , Células Cultivadas , DNA/análise , Regulação para Baixo , Regulação da Expressão Gênica/fisiologia , Humanos , Melanócitos/efeitos dos fármacos , Melanoma/patologia , RNA/análise , Células Tumorais Cultivadas
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