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1.
Appl Environ Microbiol ; 72(12): 7687-93, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17012597

RESUMO

The U.S. Environmental Protection Agency conducted an experiment to evaluate the effectiveness of a commercial autoclave for treating simulated building decontamination residue (BDR). The BDR was intended to simulate porous materials removed from a building deliberately contaminated with biological agents such as Bacillus anthracis (anthrax) in a terrorist attack. The purpose of the tests was to assess whether the standard operating procedure for a commercial autoclave provided sufficiently robust conditions to adequately destroy bacterial spores bound to the BDR. In this study we investigated the effects of several variables related to autoclaving BDR, including time, temperature, pressure, item type, moisture content, packing density, packing orientation, autoclave bag integrity, and autoclave process sequence. The test team created simulated BDR from wallboard, ceiling tiles, carpet, and upholstered furniture, and embedded in the BDR were Geobacillus stearothermophilus biological indicator (BI) strips containing 10(6) spores and thermocouples to obtain time and temperature profile data associated with each BI strip. The results indicated that a single standard autoclave cycle did not effectively decontaminate the BDR. Autoclave cycles consisting of 120 min at 31.5 lb/in2 and 275 degrees F and 75 min at 45 lb/in2 and 292 degrees F effectively decontaminated the BDR material. Two sequential standard autoclave cycles consisting of 40 min at 31.5 lb/in2 and 275 degrees F proved to be particularly effective, probably because the second cycle's evacuation step pulled the condensed water out of the pores of the materials, allowing better steam penetration. The results also indicated that the packing density and material type of the BDR in the autoclave could have a significant impact on the effectiveness of the decontamination process.


Assuntos
Bacillaceae/crescimento & desenvolvimento , Materiais de Construção/microbiologia , Esporos Bacterianos/crescimento & desenvolvimento , Vapor , Esterilização , Bacillaceae/fisiologia , Descontaminação/métodos , Pisos e Cobertura de Pisos , Decoração de Interiores e Mobiliário , Resíduos de Serviços de Saúde , Esterilização/instrumentação , Esterilização/métodos , Esterilização/normas , Temperatura , Fatores de Tempo
2.
J Med Genet ; 39(12): 882-92, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12471200

RESUMO

INTRODUCTION: Medullary cystic kidney disease 2 (MCKD2) and familial juvenile hyperuricaemic nephropathy (FJHN) are both autosomal dominant renal diseases characterised by juvenile onset of hyperuricaemia, gout, and progressive renal failure. Clinical features of both conditions vary in presence and severity. Often definitive diagnosis is possible only after significant pathology has occurred. Genetic linkage studies have localised genes for both conditions to overlapping regions of chromosome 16p11-p13. These clinical and genetic findings suggest that these conditions may be allelic. AIM: To identify the gene and associated mutation(s) responsible for FJHN and MCKD2. METHODS: Two large, multigenerational families segregating FJHN were studied by genetic linkage and haplotype analyses to sublocalise the chromosome 16p FJHN gene locus. To permit refinement of the candidate interval and localisation of candidate genes, an integrated physical and genetic map of the candidate region was developed. DNA sequencing of candidate genes was performed to detect mutations in subjects affected with FJHN (three unrelated families) and MCKD2 (one family). RESULTS: We identified four novel uromodulin (UMOD) gene mutations that segregate with the disease phenotype in three families with FJHN and in one family with MCKD2. CONCLUSION: These data provide the first direct evidence that MCKD2 and FJHN arise from mutation of the UMOD gene and are allelic disorders. UMOD is a GPI anchored glycoprotein and the most abundant protein in normal urine. We postulate that mutation of UMOD disrupts the tertiary structure of UMOD and is responsible for the clinical changes of interstitial renal disease, polyuria, and hyperuricaemia found in MCKD2 and FJHN.


Assuntos
Hiperuricemia/genética , Mucoproteínas/genética , Mutação/genética , Rim Policístico Autossômico Dominante/genética , Insuficiência Renal/genética , Alelos , Sequência de Bases , Pré-Escolar , Mapeamento Cromossômico , Cromossomos Humanos Par 16/genética , Análise Mutacional de DNA , Éxons/genética , Feminino , Marcadores Genéticos/genética , Gota/genética , Gota/fisiopatologia , Haplótipos/genética , Humanos , Hiperuricemia/fisiopatologia , Escore Lod , Masculino , Linhagem , Fenótipo , Mapeamento Físico do Cromossomo , Rim Policístico Autossômico Dominante/fisiopatologia , Insuficiência Renal/fisiopatologia , Uromodulina
4.
J Neurosurg ; 94(2): 293-300, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11213968

RESUMO

OBJECT: Coexpression of platelet-derived growth factor (PDGF)-BB and activated PDGF-beta receptor in meningioma cells indicates that this cytokine may act as an autocrine or paracrine stimulant of meningioma growth. The intracellular events transducing signals from PDGF-beta receptor tyrosine kinases are unknown. In this study the authors evaluated whether or not mitogen-activated protein kinases (MAPKs) are expressed in meningiomas, regulate their growth, and transduce mitogenic signals of PDGF-BB. METHODS: Ten human meningioma tumors as well as cells cultured from two normal leptomeninges and 10 additional human meningiomas were evaluated using Western blot analysis to determine the presence of MAPK and phosphorylated (activated) MAPK. The effects of PD098059, a selective inhibitor of MAPK phosphorylation/activation, on proliferation of meningioma cells stimulated with 10% fetal bovine serum was also evaluated. Last, the authors evaluated whether PDGF-BB stimulation of meningioma cells was associated with activation of MAPK. Western blots of lysates from meningiomas and from cultured leptomeningeal and meningioma cells demonstrated MAPK and phosphorylated MAPK. Treatment with PD098059 produced a 52 to 84% (x = 69.8) loss in [3H]thymidine incorporation, which was associated with a partial or complete loss of phosphorylated MAPK after 3 days of treatment. The PDGF-BB produced a significant increase in [3H]thymidine incorporation and phosphorylation of MAPK at 1 and 3 days. Coadministration of PD098059 completely blocked PDGF-BB's stimulation of [3H]thymidine incorporation and cell proliferation concomitant with reduced MAPK phosphorylation. CONCLUSIONS: The findings indicate that MAPK is constitutively expressed in leptomeningeal and meningioma cells and transduces mitogenic signals of PDGF, contributing to the growth of human meningiomas.


Assuntos
Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Meníngeas/fisiopatologia , Meningioma/fisiopatologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Transdução de Sinais/fisiologia , Adolescente , Adulto , Idoso , Western Blotting , Ativação Enzimática/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Neuropsychology ; 15(4): 434-43, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11761032

RESUMO

Object-naming impairment is common among temporal lobe epilepsy (TLE) patients, but other aspects of semantic memory have received limited attention in this population. This study examined object-naming ability and depth of semantic knowledge in healthy controls (n = 29) and patients with early onset TLE (n = 21). After administration of the Boston Naming Test (BNT), the authors asked participants to provide detailed definitions of 6 BNT objects. The TLE group demonstrated a significant deficit relative to controls in both object-naming ability and semantic knowledge for the target objects, even after controlling for IQ. In a multiple regression analysis that included other neuropsychological test scores as independent variables, the semantic knowledge score was the only significant predictor of patients' object-naming performance. Thus, at the group level, early onset TLE patients have a semantic knowledge deficit that contributes to dysnomia.


Assuntos
Anomia/diagnóstico , Epilepsia do Lobo Temporal/diagnóstico , Rememoração Mental , Reconhecimento Visual de Modelos , Semântica , Adolescente , Adulto , Anomia/psicologia , Epilepsia do Lobo Temporal/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
6.
Semin Pediatr Neurol ; 7(3): 166-77, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11023174

RESUMO

Neuroimaging and the neuropsychological evaluation are important components of the presurgical evaluation for epilepsy surgery. Advances in neuroimaging over the last decade, to a large part, underlie improvements in pediatric epilepsy surgery outcomes. The neuropsychological evaluation plays an important role in the evaluation of the older child and adolescent, particularly in the evaluation of mesial temporal sclerosis. However, its role in the young child being considered for surgery remains to be defined. This section reviews the definition of medical intractability, issues related to medication withdrawal during video-EEG monitoring, recent neuroimaging advances, and the neuropsychological evaluation.


Assuntos
Encéfalo/patologia , Epilepsia/diagnóstico , Epilepsia/cirurgia , Testes Neuropsicológicos , Adolescente , Anticonvulsivantes , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Encéfalo/cirurgia , Criança , Pré-Escolar , Diagnóstico Diferencial , Dominância Cerebral , Eletroencefalografia/métodos , Epilepsia/patologia , Epilepsia/psicologia , Humanos , Cuidados Pré-Operatórios , Prognóstico , Cintilografia/métodos , Convulsões/induzido quimicamente , Resultado do Tratamento
7.
J Biol Chem ; 275(32): 24565-74, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10835423

RESUMO

The alpha(v)beta(3) integrin has been shown to bind several ligands, including osteopontin and vitronectin. Its role in modulating cell migration and downstream signaling pathways in response to specific extracellular matrix ligands has been investigated in this study. Highly invasive prostate cancer PC3 cells that constitutively express alpha(v)beta(3) adhere and migrate on osteopontin and vitronectin in an alpha(v)beta(3)-dependent manner. However, exogenous expression of alpha(v)beta(3) in noninvasive prostate cancer LNCaP (beta(3)-LNCaP) cells mediates adhesion and migration on vitronectin but not on osteopontin. Activation of alpha(v)beta(3) by epidermal growth factor stimulation is required to mediate adhesion to osteopontin but is not sufficient to support migration on this substrate. We show that alpha(v)beta(3)-mediated cell migration requires activation of the phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B (PKB/AKT) pathway since wortmannin, a PI 3-kinase inhibitor, prevents PC3 cell migration on both osteopontin and vitronectin; furthermore, alpha(v)beta(3) engagement by osteopontin and vitronectin activates the PI 3-kinase/AKT pathway. Migration of beta(3)-LNCaP cells on vitronectin also occurs through activation of the PI 3-kinase pathway; however, AKT phosphorylation is not increased upon engagement by osteopontin. Furthermore, phosphorylation of focal adhesion kinase (FAK), known to support cell migration in beta(3)-LNCaP cells, is detected on both substrates. Thus, in PC3 cells, alpha(v)beta(3) mediates cell migration and PI 3-kinase/AKT pathway activation on vitronectin and osteopontin; in beta(3)-LNCaP cells, alpha(v)beta(3) mediates cell migration and PI 3-kinase/AKT pathway activation on vitronectin, whereas adhesion to osteopontin does not support alpha(v)beta(3)-mediated cell migration and PI 3-kinase/AKT pathway activation. We conclude therefore that alpha(v)beta(3) exists in multiple functional states that can bind either selectively vitronectin or both vitronectin and osteopontin and that can differentially activate cell migration and intracellular signaling pathways in a ligand-specific manner.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Vitronectina/fisiologia , Sialoglicoproteínas/fisiologia , Vitronectina/fisiologia , Androstadienos/farmacologia , Quimiotaxia , Inibidores Enzimáticos/farmacologia , Fibronectinas/fisiologia , Humanos , Masculino , Osteopontina , Fosfoproteínas/fisiologia , Fosforilação , Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Transfecção , Células Tumorais Cultivadas , Wortmanina
8.
Neurology ; 54(5): 1161-5, 2000 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-10720291

RESUMO

OBJECTIVE: To examine the relationship of preoperative fluorodeoxyglucose (FDG)-PET asymmetry in temporal lobe metabolism and memory outcome after anterior temporal lobectomy (ATL). METHODS: In a university-based epilepsy surgery center, 60 ATL patients (27 left, 33 right) were divided into two groups: no/mild (n = 21) or moderate/ severe (n = 39) asymmetry in temporal lobe hypometabolism as determined by FDG-PET. All patients were nonretarded, at least 18 years of age, left-hemisphere speech dominant, without MRI abnormalities other than hippocampal atrophy, and with unilateral temporal lobe origin of intractable complex partial seizures. Neuropsychological measures of intelligence and verbal and visual memory function were assessed preoperatively and 6 months postoperatively. RESULTS: Left ATL patients with no/mild asymmetry in FDG-PET temporal lobe metabolism exhibited significantly greater verbal memory decline compared with left ATL patients with moderate/severe hypometabolism. There was no significant relationship between PET asymmetry and pre- to postsurgical IQ change. No significant relationship was observed between extent of PET hypometabolism and memory outcome for right ATL patients. CONCLUSIONS: FDG-PET asymmetry can be added to the preoperative clinical markers that appear useful in predicting verbal memory decline after left ATL.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico por imagem , Memória/fisiologia , Lobo Temporal/diagnóstico por imagem , Adulto , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/psicologia , Feminino , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/metabolismo , Lobo Temporal/fisiopatologia , Lobo Temporal/cirurgia , Tomografia Computadorizada de Emissão
9.
Epilepsy Behav ; 1(3): 184-90, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12609152

RESUMO

Purpose. The goals of this work were to determine: (1) the nature and extent of differences in self-reported psychiatric symptoms between patients with temporal lobe epilepsy and matched healthy controls, (2) the relationship between chronicity (duration) of temporal lobe epilepsy and comorbid interictal psychiatric symptoms, and (3) the impact of comorbid psychiatric symptoms on self-reported health-related quality of life. Methods. Patients with temporal lobe epilepsy (n = 54) and healthy controls (n = 38) were administered the Symptom Checklist-90-Revised (SCL-90-R) to assess the nature and severity of psychiatric symptomatology and epilepsy patients completed the Quality of Life in Epilepsy-89 (QOLIE-89) to define health-related quality of life. Among epilepsy patients the SCL-90-R scales were examined in relation to chronicity of temporal lobe epilepsy as well as the impact of comorbid emotional-behavioral distress on health-related quality of life. Results. Compared with healthy controls, patients with epilepsy exhibited significantly higher (worse) scores across all but one of the 12 SCL-90-R scales. Among patients with epilepsy, increasing chronicity was associated with significantly higher (worse) scores across all SCL-90-R scales and increased emotional-behavioral distress was associated with lower (worse) scores across all 17 QOLIE-89 scales. Conclusion. Comorbid interictal psychiatric symptoms are elevated among patients with temporal lobe epilepsy compared with healthy controls and appear to be modestly associated with increasing chronicity (duration) of epilepsy. This comorbid emotional-behavioral distress is specifically associated with a significantly poorer health-related quality of life, and suggests that quality-of-life research should devote greater attention to the potential impact of comorbid psychiatric distress.

10.
Dev Med Child Neurol ; 41(11): 724-31, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10576636

RESUMO

Neuropsychological and behavioral status were examined in 57 children aged 7 to 16 years with complex partial seizures (CPS) and compared with 27 sibling control children of the same age. Epilepsy had a significant effect on both cognitive and behavioral adjustment measures. Children with CPS had significant impairment across all seven cognitive domains assessed, reflective of a profile of relatively diffuse and generalized cognitive dysfunction. Age at onset of recurrent seizures was the strongest and most consistent predictor of adequacy of cognitive functioning; earlier age at onset was associated with poorer cognitive status. Children with CPS also had more problems compared with sibling control children on measures of social and school competence and internalizing behavior problems, but not externalizing behaviors. Further, frequency of seizure activity in the past year, rather than age at seizure onset, emerged as the strongest predictor of these behavioral difficulties. These findings are discussed in the context of understanding the impact of CPS on cognition and behavioral adjustment, and identifying the contribution of various aspects of the neurodevelopmental course of CPS to these issues.


Assuntos
Transtornos do Comportamento Infantil/complicações , Transtornos do Comportamento Infantil/diagnóstico , Epilepsia Parcial Complexa/complicações , Testes Neuropsicológicos , Logro , Adolescente , Criança , Transtornos Cognitivos/complicações , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Transtornos das Habilidades Motoras/complicações , Transtornos das Habilidades Motoras/diagnóstico , Índice de Gravidade de Doença
12.
Neurology ; 53(5 Suppl 2): S3-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10496228

RESUMO

This article briefly presents one approach to conceptualizing known and suspected risk factors for co-morbid psychiatric disorder in epilepsy. The utility of this model is then reviewed by examining selected neurobiologic, psychosocial, and iatrogenic risk factors for a common co-morbid psychiatric disorder, interictal depression. Finally, data are presented concerning the rates of current and lifetime mood disorders among a sample of 76 patients with chronic complex partial seizures, the degree to which co-morbid depression has been recognized and treated in chronic epilepsy, and the health-related quality of life status associated with current and past mood disorders. Finally, these findings are related to the larger literature concerned with the recognition and treatment of depression.


Assuntos
Transtorno Depressivo/psicologia , Epilepsia/psicologia , Adulto , Doença Crônica , Transtorno Depressivo/complicações , Epilepsia/complicações , Humanos
13.
Cancer Res ; 59(7): 1655-64, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10197643

RESUMO

The highly invasive human prostate cancer PC3 cell line was found to express the alpha(v)beta3 integrin; in contrast, the noninvasive LNCaP prostate cancer cell line did not express alpha(v)beta3. PC3 cells adhered to and migrated on vitronectin (VN), an alpha(v)beta3 ligand expressed in mature bone where prostate cancer cells preferentially metastasize. In contrast, LNCaP cells did not adhere to or migrate on VN. Analysis of primary human prostate cancer cells isolated from 16 surgical specimens, showed that these cells expressed alpha(v)beta3, whereas normal prostate epithelial cells did not. In addition, only primary prostate cancer cells adhered to and migrated on VN. The role of alpha(v)beta3 in mediating prostate epithelial cell migration was confirmed using LNCaP cell transfectants expressing beta3 (beta3-LNCaP). Exogenous expression of alpha(v)beta3 induced LNCaP cells to adhere to and migrate on VN. In response to alpha(v)beta3 engagement, increased tyrosine phosphorylation of focal adhesion kinase (FAK), a signaling molecule activated by integrins and able to modulate cell migration, was detected. Transfection of FAK-related nonkinase, known to compete with FAK for its correct localization and phosphorylation, caused inhibition of beta3-LNCaP cell migration, specifically on VN. These data indicate that de novo expression of alpha(v)beta3 integrin in prostate cancer cells generates a migratory phenotype that is modulated by a FAK signaling pathway. This study points to alpha(v)beta3 as potential target in prostate cancer cell invasion and metastasis.


Assuntos
Moléculas de Adesão Celular/fisiologia , Neoplasias da Próstata/patologia , Proteínas Tirosina Quinases/fisiologia , Receptores de Vitronectina/fisiologia , Movimento Celular , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Masculino , Fosforilação , Células Tumorais Cultivadas , Vitronectina/fisiologia
15.
J Cell Sci ; 111 ( Pt 4): 469-78, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9443896

RESUMO

Integrins and growth factor receptors act synergistically to modulate cellular functions. The alphavbeta3 integrin and the platelet-derived growth factor receptor have both been shown to play a positive role in cell migration. We show here that a platelet derived growth factor-BB gradient stimulated migration of rat microvascular endothelial cells on vitronectin (9.2-fold increase compared to resting cells) in a alphavbeta3 and RGD-dependent manner. In contrast, this response was not observed on a beta1 integrin ligand, laminin; background levels of migration, in response to a platelet derived growth factor-BB gradient, were observed on this substrate or on bovine serum albumin (2.4- or 2.0-fold, respectively). Comparable results were obtained using NIH-3T3 cells. Platelet derived growth factor-BB did not change the cells' ability to adhere to vitronectin, nor did it stimulate a further increase in proliferation on vitronectin versus laminin. In addition, platelet derived growth factor-BB stimulation of NIH-3T3 cells did not alter the ability of alphavbeta3 to bind RGD immobilized on Sepharose. The alphavbeta3 integrin and the platelet derived growth factor receptor-beta associate in both microvascular endothelial cells and NIH-3T3 cells, since they coprecipitated using two different antibodies to either alphavbeta3 or to the platelet derived growth factor receptor-beta. In contrast, beta1 integrins did not coprecipitate with the platelet derived growth factor receptor-beta. These results point to a novel pathway, mediated by the synergistic activity of alphavbeta3 and the platelet derived growth factor receptor-beta, that regulates cell migration and, therefore, might play a role during neovessel formation and tissue infiltration.


Assuntos
Movimento Celular/fisiologia , Receptores do Fator de Crescimento Derivado de Plaquetas/fisiologia , Receptores de Vitronectina/metabolismo , Células 3T3 , Animais , Antígenos CD/análise , Becaplermina , Adesão Celular , Divisão Celular , Células Cultivadas , Endotélio Vascular/citologia , Humanos , Integrina alfaV , Laminina , Camundongos , Oligopeptídeos/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Proto-Oncogênicas c-sis , Ratos , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Vitronectina/isolamento & purificação , Vitronectina
16.
Cell Growth Differ ; 8(7): 773-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9218871

RESUMO

Decreased expression of E-cadherin (E-cad), a calcium-dependent cell adhesion molecule, has been seen in many different epithelial cancers. Although somatic mutations in the E-cad gene have been identified in a small subset of tumors, in the majority of cancers, the mechanisms underlying loss of E-cad expression are poorly understood. We have cloned the human E-cad promoter and defined its critical components in functional assays. In eight human breast cancer cell lines, there was a striking correlation between endogenous E-cad gene expression and E-cad promoter activity observed following the introduction of reporter gene constructs into the lines. These and other observations suggest that defects in trans-acting pathways regulation E-cad expression are the primary basis for the loss of its expression in most breast cancers. The results have significant implications for understanding the gene expression differences that underlie tumor heterogeneity and progression events in breast and other epithelial cancers.


Assuntos
Neoplasias da Mama/genética , Caderinas/genética , Regulação Neoplásica da Expressão Gênica/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Caderinas/análise , Clonagem Molecular , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Decitabina , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Transativadores , Fator de Transcrição AP-2 , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Células Tumorais Cultivadas
18.
J Neurosci ; 15(12): 8295-301, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8613762

RESUMO

Repeated activation of neural pathways by kindling induces brief seizures, permanent increases in seizure susceptibility, neuronal loss in the hippocampus, and mossy fiber sprouting in the dentate gyrus. Because kindling induces permanent cellular alterations in hippocampal pathways that have been implicated in memory, it was of interest to determine if kindling also induces long-lasting impairments in a spatial memory task in rats. In this study, the effects of kindling on memory were investigated by assessing kindled rats in a radial arm maze behavior that is impaired by hippocampal damage. Kindled rats studied at 1 month after the last of 30-134 evoked generalized tonic-clonic seizures acquired competence in the performance of the radial arm maze task at a rate that was indistinguishable from age-matched normal controls, but demonstrated a deficit in the ability to repeat the task on consecutive days. The repetition deficit was not observed in rats that experienced three afterdischarges or three generalized tonic-clonic seizures, and the severity of the deficit varied directly with the number of evoked kindled seizures. Repeated brief seizures evoked by kindling induced a long-lasting deficit in a radial arm maze task that is a rodent model of memory. The observation of a long-lasting deficit in radial arm maze performance in kindled rats suggests that the cellular alterations induced in the hippocampus by seizures could contribute to the memory dysfunction in human epilepsy.


Assuntos
Excitação Neurológica , Aprendizagem em Labirinto , Transtornos da Memória/etiologia , Convulsões/complicações , Animais , Doença Crônica , Eletrofisiologia , Transtornos da Memória/fisiopatologia , Ratos , Ratos Sprague-Dawley , Recidiva , Valores de Referência , Convulsões/fisiopatologia
19.
J Exp Med ; 182(5): 1591-6, 1995 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7595230

RESUMO

Naive CD4+ T cells can differentiate into cells predominantly involved in humoral immunity, known as T helper type 2 cells (Th2), or cells involved in cell-mediated immunity, known as Th1 cells. In this report, we show that priming of CD4+ T cells bearing a transgene-encoded T cell receptor can lead to differentiation into Th1-like cells producing abundant interferon gamma when the cells are exposed to high antigen doses, while low doses of the same peptide induce cells with the same T cell receptor to differentiate into Th2-like cells producing abundant interleukin 4. Thus antigen dose is one factor that can control the differentiation fate of a naive CD4+ T cell.


Assuntos
Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular , Grupo dos Citocromos c/imunologia , Relação Dose-Resposta Imunológica , Feminino , Interferon gama/biossíntese , Interleucina-4/biossíntese , Masculino , Camundongos , Camundongos Transgênicos , Mariposas , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/química , Células Th1/citologia , Células Th1/imunologia , Células Th2/citologia , Células Th2/imunologia
20.
Oncogene ; 11(7): 1319-26, 1995 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-7478552

RESUMO

Alterations in intercellular junction and membrane cytoskeletal proteins may underlie some of the morphological, invasive and metastatic properties of cancer. E-cadherin, a transmembrane protein that functions in epithelial cell-cell interactions at adherens junctions, is linked to the membrane cytoskeletal matrix through interactions with alpha- and beta-catenin. We have carried out studies of E-cadherin and alpha- and beta-catenin in 18 breast cancer cell lines to determine the prevalence and nature of alterations in these genes in breast cancer. Ten lines failed to express E-cadherin protein at detectable levels and seven failed to produce detectable levels of E-cadherin transcripts. In a line lacking E-cadherin expression (SK-BR-3) a homozygous deletion of a large portion of the E-cadherin gene was noted. Localized sequence alterations in E-cadherin transcripts were not identified in any lines. In contrast to the results of a previous study, no relationship was identified between E-cadherin expression and HER-2/NEU expression. Two of the 18 lines had no detectable alpha-catenin protein and six others had reduced levels. The two lines lacking alpha-catenin protein had reduced or undetectable levels of alpha-catenin transcripts, while no consistent changes in alpha-catenin transcript levels were seen in the lines with reduced, but detectable, levels of alpha-catenin protein. Similarly, although two lines lacked beta-catenin protein, in most lines the levels of beta-catenin transcripts and protein were not well correlated with one another. Our findings suggest that alterations in E-cadherin and alpha- and beta-catenin expression are frequent in human breast cancer-derived cell lines, and that in some cases the decreased expression may result from mutations in the genes. Furthermore, the frequent alterations in the expression of these proteins argue that loss of function in the E-cadherin-catenin pathway may be critical in the development of many breast cancers.


Assuntos
Neoplasias da Mama/genética , Caderinas/genética , Proteínas do Citoesqueleto/genética , Mutação , Transativadores , Sequência de Bases , Southern Blotting , Western Blotting , Neoplasias da Mama/patologia , Caderinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Feminino , Deleção de Genes , Expressão Gênica , Humanos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Receptor ErbB-2/genética , Ribonucleases/metabolismo , Células Tumorais Cultivadas , alfa Catenina , beta Catenina
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