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1.
J Clin Oncol ; 18(8): 1668-75, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10764427

RESUMO

PURPOSE: To examine the relationship between pathologic margin status and outcome at 8 years after breast-conserving surgery and radiation therapy. PATIENTS AND METHODS: The study population comprised 533 patients with International Union Against Cancer/American Joint Committee on Cancer clinical stage I or II breast cancer who had assessable margins, who received at least 60 Gy to the primary tumor bed, and who had more than 8 years of potential follow-up. Each margin was scored (according to the presence of invasive or in situ disease that touched the inked surgical margin) as one of the following: negative, close, focally positive, or extensively positive. Outcome at 8 years was calculated using crude rates of first site of failure. A polychotomous logistic regression analysis was performed. Median follow-up time was 127 months. RESULTS: At 8 years, patients with close margins and those with negative margins both had a rate of local recurrence (LR) of 7%. Patients with extensively positive margins had an LR rate of 27%, whereas patients with focally positive margins had an intermediate rate of LR of 14%. In the polychotomous logistic regression model, margin status and the use of systemic therapy were the only two variables that had significant effects on the risk ratio of LR to remaining alive and free of disease. Among the 45 patients with focally positive margins who received systemic therapy, the crude LR rate was 7% at 8 years (95% confidence interval, 1% to 20%). CONCLUSION: Pathologic margin status and the use of adjuvant systemic therapy are the most important factors associated with LR among patients treated with breast-conserving surgery and radiation therapy.


Assuntos
Neoplasias da Mama/terapia , Mastectomia Segmentar , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos
2.
J Neuropathol Exp Neurol ; 59(12): 1044-50, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11138924

RESUMO

Glioblastomas only rarely metastasize to sites outside the central nervous system, for reasons that are poorly understood. We report the clinicopathological and molecular genetic findings in 6 patients with metastatic glioblastoma. Four patients were under the age of 32 and all but 1 patient died within 2 yr of diagnosis. The number of metastases ranged from 1 to 3. At the time of death, 3 patients had apparent tumor control at their primary site. We evaluated DNA from both primary and metastatic glioblastomas for genetic alterations commonly found in glioblastomas: TP53 mutations, CDKN2A/p16 deletions, EGFR amplification, and allelic loss of chromosomes 1p, 10q and 19q. Four of 6 cases had TP53 mutations and only single cases had EGFR amplification, CDKN2A/p16 deletions, or allelic loss of 1p, 10q and 19q; 2 cases had no detectable genetic alterations. In 2 cases, the primary and metastatic tumors had identical genotypes. Remarkably, however, 2 cases had different TP53 alterations in the primary and metastatic lesions, or among the metastatic tumors, which suggests that some metastatic deposits may represent emergence of subclones that were not necessarily dominant in the primary tumor. The present observations and a review of the recent literature demonstrate that metastatic glioblastomas tend to occur in younger adults who do not follow long clinical courses, and may be characterized by TP53 mutations and differential clonal selection.


Assuntos
Glioblastoma/patologia , Glioblastoma/secundário , Adulto , DNA de Neoplasias/genética , Evolução Fatal , Genes erbB-1/genética , Genes p16/genética , Genes p53/genética , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação/genética
3.
Brain Res ; 570(1-2): 75-84, 1992 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-1319795

RESUMO

Properties of inward Na+ currents (INa) were examined in dissociated diencephalic neurons whose plasma membrane fatty acid composition had been altered. These neurons were grown in a defined medium supplemented with essential fatty acids (EFA) of either the w3 class (linolenic acid, 18:3w3) or the w6 class (linoleic acid, 18:2w6), which resulted in a two-fold increase in the plasma membrane phospholipid polyunsaturated fatty acid (PUFA) concentration. The properties of the inward INa of these neurons were compared with those of control neurons grown in the absence of any supplemented fatty acids. The INa of neurons supplemented with a non-essential fatty acid (NFA) of w9 class (oleic acid, 18:1w9) was also examined. Several properties have been modified to different degrees. The ratio of the amplitudes between the fast and the slow decay components as well as the time constant of the fast decay component changed consistently and reversibly with the membrane phospholipid PUFA composition. The current-voltage relationships, channel selectivity, rates of inactivation and recovery from inactivation did not change. Other parameters, such as time-to-peak and steady-state inactivation curves, have changed in EFA- and NFA-supplemented cultures and did not reverse completely. These findings demonstrate that the kinetics of INa can be modified by fatty acid supplementation. These effects can be correlated, in part, with alterations in plasma membrane phospholipid fatty acid composition.


Assuntos
Diencéfalo/efeitos dos fármacos , Ácidos Graxos Essenciais/farmacologia , Ácidos Graxos Insaturados/farmacologia , Neurônios/efeitos dos fármacos , Canais de Sódio/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Cinética , Ratos
4.
J Neurosurg ; 87(2): 294-300, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9254096

RESUMO

Activation of complement results in formation of membrane attack complexes (MACs) that can insert themselves either into cells that initiate complement activation or into nearby ("innocent bystander") cells. The MACs form large-conductance, nonspecific ion channels that can cause lytic or sublytic cell damage. The authors used a highly sensitive patch clamp technique to assess the contribution of the bystander effect to the pathophysiology of cerebral vasospasm. They compared the effect of complement activation by autologous aged versus fresh erythrocytes on the membrane conductance of freshly isolated rat cerebral artery smooth-muscle cells. In the presence of autologous serum aged, but not fresh, erythrocytes caused a large increase in membrane conductance, an effect that was prevented by heat-inactivating the serum. Ethyleneglycol tetraacetic acid in the presence of Mg++ attenuated the effect, indicating that complement activation was taking place via the classic pathway. The effect was reproduced by zymosan-activated autologous serum, suggesting that such changes in conductance could result from insertion of MACs secondary to a bystander effect. Both C8- and C9-depleted heterologous sera produced minimal effects that were converted to full effect by addition of the missing complement component. Superoxide dismutase plus catalase did not attenuate the conductance changes produced by autologous serum plus aged erythrocytes. Autologous serum plus aged erythrocyte membrane ghosts that were free of lysate caused a typical increase in conductance. This study demonstrates that complement activation by aged erythrocytes can result in MAC insertion into innocent bystander smooth-muscle cell membranes and that this mechanism, heretofore undescribed, may contribute to development of vasospasm after subarachnoid hemorrhage.


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento/fisiologia , Proteínas do Sistema Complemento/fisiologia , Eritrócitos/fisiologia , Ataque Isquêmico Transitório/fisiopatologia , Potenciais da Membrana/fisiologia , Músculo Liso Vascular/fisiologia , Animais , Modelos Biológicos , Técnicas de Patch-Clamp , Ratos
5.
Patient Educ Couns ; 33(2): 149-59, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9732655

RESUMO

BACKGROUND: Having a premature baby is acknowledged to be stressful to parents. Journal writing combines practical, emotional and informational support that may be useful to these parents. METHODS: We conducted a study to assess the potential for promoting journal-writing for parents receiving social support in a special care nursery (SCN). Parents were provided with educational material on journal writing, and subsequently surveyed concerning their journal-writing during their child's hospitalization. RESULTS: Of the 73 parents enrolled, 32% kept a journal; of these, 73% felt it helped considerably in reducing stress, and 68% used it as a means of addressing the most stressful elements of their nursery experience. Journals were used primarily to document involvement in care (45%), record-keeping (36%), and organization of thoughts (27%). All of those who kept a journal recommended it for use by other parents. CONCLUSIONS: Encouraging parents to keep a journal is a constructive way of dealing with the SCN-related stress.


Assuntos
Adaptação Psicológica , Recém-Nascido Prematuro , Mães/psicologia , Apoio Social , Estresse Psicológico/prevenção & controle , Redação , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Mães/educação , Projetos Piloto , Estresse Psicológico/psicologia
6.
J Neurophysiol ; 65(5): 1011-21, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1651371

RESUMO

1. Dissociated, synchronized (G1 phase of cell cycle), and birth-dated fetal rat diencephalic neurons were grown in a serum-free defined medium. The gigaseal whole-cell voltage-clamp technique was used to measure the inward Na+ currents (INa) from morphologically identified bipolar neurons. The earliest expressed somatic INa has been characterized and compared with that present at a later date. 2. The identity of the INa was established on the basis of its reversal potential and reversible blockade by tetrodotoxin (TTX). Close agreement between the measured reversal potentials (68.5 +/- 1.3 and 38.3 +/- 2.4 mV, mean +/- SE) and calculated Nernst equilibrium potentials (64.6 and 34.7 mV) at two different bath Na+ concentrations (120 and 35 mM, respectively) suggests that the channels are highly selective for Na+. 3. The peak INa density increased from 47.7 +/- 2.9 pA/pF in younger neurons (5-6 days in culture) to 93.9 +/- 6.4 pA/pF in older neurons (12-13 days in culture). The activation voltage and the voltage for peak current were also shifted by 10 mV in the hyperpolarizing direction, from -30 and +10 mV in younger neurons to -40 and 0 mV in older neurons, respectively. However, the reversal potential did not change (69.2 +/- 2.3 and 68.5 +/- 1.3 mV in younger and older neurons, respectively). 4. In older neurons the steady-state inactivation parameters (V1/2, the voltage at which inactivation was 50% of maximum, and kh, the voltage at which there is an e-fold change in inactivation) were significantly altered. V1/2 was shifted from -41.5 +/- 2.3 to -48.8 +/- 1.8 mV, and kh was increased from 6.2 +/- 0.5 to 8.9 +/- 0.4 mV. However, the time course of activation and the rates of inactivation and recovery from inactivation were unchanged. 5. In both groups, the INa decays were best described by a sum of two exponentials. The corresponding time constants were voltage dependent. Also, the amplitudes of the two components were differentially affected by membrane potential and niflumic acid. 6. The extrapolated amplitudes of both the fast and the slow components of INa were larger in older neurons, but the ratio of the amplitudes of the two components did not change with age. The voltage dependencies of the time constants of both components were altered. 7. We conclude that INa in fetal rat diencephalic neurons grown in a defined medium with only essential nutrients undergoes in vitro changes in current density and in some, but not all, kinetic parameters.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diencéfalo/metabolismo , Neurônios/metabolismo , Canais de Sódio/metabolismo , Animais , Membrana Celular/metabolismo , Células Cultivadas , Diencéfalo/citologia , Eletrofisiologia , Feminino , Cinética , Potenciais da Membrana/fisiologia , Ácido Niflúmico/farmacologia , Gravidez , Ratos , Tetrodotoxina/farmacologia
7.
J Neurochem ; 55(5): 1537-45, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2213009

RESUMO

Modifications of plasma membrane acyl-linked phospholipid fatty acid composition were produced by supplementing the culture medium with essential fatty acids. The plasma membrane fraction was purified by Percoll gradient centrifugation from dissociated fetal rat brain cells grown in a serum-free culture medium. Both the concentration dependence and the time course of the modifications were examined. Supplementation of the medium with essential polyunsaturated fatty acid, linolenic acid (18:3 omega 3) or linoleic acid (18:2 omega 6), produced incorporation of the elongated and desaturated products of omega 3 or omega 6 class, respectively, i.e., the incorporation was class specific. Within each class, the most unsaturated and elongated members, i.e., terminal members, were preferentially incorporated until they reached a maximum concentration within 6-7 days. At higher concentrations of supplemented fatty acids, additional class specific incorporation in plasma membrane was produced by an increase in the concentration of intermediate members. At the same time, the concentration of monounsaturated fatty acids declined and that of saturated fatty acids remained unchanged. The modifications in fatty acid composition were reversible, with the time course similar to that of incorporation. The total plasma membrane phospholipid and sterol contents did not change with alterations of fatty acid composition, but did change with time in culture. This preparation should prove useful for investigating the role of polyunsaturated fatty acids in brain cell functions, including neuronal excitability.


Assuntos
Encéfalo/metabolismo , Ácidos Graxos/metabolismo , Animais , Encéfalo/citologia , Membrana Celular/metabolismo , Células Cultivadas , Meios de Cultura , Ácidos Graxos/química , Feto , Metabolismo dos Lipídeos , Fosfolipídeos/metabolismo , Ratos , Esteróis/metabolismo
8.
Mol Med Today ; 6(8): 324-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10904250

RESUMO

Normal tissue homeostasis is maintained by dynamic interactions between epithelial cells and their microenvironment. As tissue becomes cancerous, there are reciprocal interactions between neoplastic cells, adjacent normal cells such as stroma and endothelium, and their microenvironments. The current dominant paradigm wherein multiple genetic lesions provide both the impetus for, and the Achilles heel of, cancer might be inadequate to understand cancer as a disease process. In the following brief review, we will use selected examples to illustrate the influence of the microenvironment in the evolution of the malignant phenotype. We will also discuss recent studies that suggest novel therapeutic interventions might be derived from focusing on microenvironment and tumor cells interactions.


Assuntos
Transformação Celular Neoplásica/patologia , Neoplasias/patologia , Animais , Transformação Celular Neoplásica/metabolismo , Matriz Extracelular/metabolismo , Homeostase , Humanos , Integrinas/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/terapia , Fenótipo , Radiação Ionizante , Fator de Crescimento Transformador beta/metabolismo , Ferimentos e Lesões/patologia
9.
J Biol Chem ; 276(40): 37069-75, 2001 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11477102

RESUMO

Interleukin-18 (IL-18) is a novel proinflammatory cytokine found in serum and joints of patients with rheumatoid arthritis (RA). We studied a novel role for IL-18 in mediating cell adhesion, a vital component of the inflammation found in RA and other inflammatory diseases. We examined the expression of cellular cell adhesion molecules E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) on endothelial cells and RA synovial fibroblasts using flow cytometry. Adhesion of the monocyte-like cell line HL-60 to endothelial cells was determined by immunofluorescence. IL-18 significantly enhanced ICAM-1 and VCAM-1 expression on endothelial cells and RA synovial fibroblasts. In addition, IL-18 induced E-selectin expression on endothelial cells and promoted the adhesion of HL-60 cells to IL-18-stimulated endothelial cells. Neutralizing anti-VCAM-1 and anti-E-selectin could completely inhibit HL-60 adherence to endothelial cells. IL-18-induced adhesion molecule expression appears to be mediated through nuclear factor kappa B (NF kappa B) and phosphatidyl-inositol 3 kinase (PI 3-kinase) since addition of inhibitors to either NF kappa B (pyrrolidine dithiocarbamate and N-acetyl-l-cysteine) or PI 3-kinase (LY294002) inhibited RA synovial fibroblast VCAM-1 expression by 50 to 60%. Addition of both inhibitors resulted in inhibition of VCAM-1 expression by 85%. In conclusion, the ability of IL-18 to induce adhesion molecule expression on endothelial cells and RA synovial fibroblasts indicates that IL-18 may contribute to RA joint inflammation by enhancing the recruitment of leukocytes into the joint. IL-18 requires NF kappa B as well as PI 3-kinase to induce VCAM-1 on RA synovial fibroblasts, suggesting that there may be two distinct pathways in IL-18-induced adhesion molecule expression.


Assuntos
Interleucina-18/farmacologia , NF-kappa B/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Transdução de Sinais/fisiologia , Acetilcisteína/farmacologia , Anticorpos Monoclonais/farmacologia , Antioxidantes/farmacologia , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Adesão Celular/efeitos dos fármacos , Selectina E/imunologia , Selectina E/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células HL-60 , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Pirrolidinas/farmacologia , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo , Tiocarbamatos/farmacologia , Molécula 1 de Adesão de Célula Vascular/imunologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
10.
Lab Invest ; 81(10): 1371-83, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11598150

RESUMO

Interleukin-18 (IL-18) is a novel proinflammatory cytokine that was recently found in synovial fluids and in synovial tissues from patients with rheumatoid arthritis (RA). To determine the participation of IL-18 in the inflammation observed in RA, we investigated the effect of IL-18 on RA synovial fibroblast chemokine production. Using FACS analysis, we showed that IL-18 induced a doubling in the production of intracellular IL-8 by RA synovial fibroblasts, and this result was confirmed by Western blot. At the extracellular level, IL-18 up-regulated the secretion of IL-8 in a dose- and time-dependent manner. IL-18 also up-regulated the other CXC chemokines, epithelial-neutrophil activating protein (ENA-78) and growth-regulated oncogene (groalpha), in a dose dependent manner, but failed to induce the production of the CC chemokine, macrophage inflammatory protein (MIP)-1alpha. By immunofluorescence and Western blot, we demonstrated that IL-18 activates the translocation of the transcription factor nuclear factor kappa B (NFkappaB) into the nucleus of RA synovial fibroblasts. IL-18 induces IL-8 secretion through NFkappaB because RA synovial fibroblasts pretreated with antisense to NFkappaB p65 oligonucleotide produce a mean of 44% less IL-8 compared with cells pretreated with the control sense oligonucleotide. These results indicate a novel role for IL-18 in inducing RA synovial fibroblast expression of CXC chemokines through NFkappaB and place this cytokine in a strategic role in the local inflammation observed in RA.


Assuntos
Artrite Reumatoide/metabolismo , Quimiocinas CXC/biossíntese , Interleucina-18/farmacologia , Membrana Sinovial/metabolismo , Artrite Reumatoide/patologia , Células Cultivadas , Fibroblastos/metabolismo , Humanos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/patologia
11.
J Immunol ; 167(3): 1644-53, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466388

RESUMO

Angiogenesis, or new blood vessel growth, is a key process in the development of synovial inflammation in rheumatoid arthritis (RA). Integral to this pathologic proliferation are proinflammatory cytokines. We hypothesized a role for IL-18 as an angiogenic mediator in RA. We examined the effect of human IL-18 on human microvascular endothelial cell (HMVEC) migration. IL-18 induced HMVEC migration at 1 nM (p < 0.05). RA synovial fluids potently induced endothelial cell migration, but IL-18 immunodepletion resulted in a 68 +/- 5% decrease in HMVEC migration (p < 0.05). IL-18 appears to act on HMVECs via alpha(v)beta(3) integrin. To test whether IL-18 induced endothelial cell tube formation in vitro, we quantitated the degree of tube formation on Matrigel matrix. IL-18, 1 or 10 nM, resulted in a 77% or 87% increase in tube formation compared with control (p < 0.05). To determine whether IL-18 may be angiogenic in vivo, we implanted IL-18 in Matrigel plugs in mice, and IL-18 at 1 and 10 nM induced angiogenesis (p < 0.05). The angiogenesis observed appears to be independent of the contribution of local TNF-alpha, as evidenced by adding neutralizing anti-TNF-alpha Ab to the Matrigel plugs. In an alternative in vivo model, sponges embedded with IL-18 or control were implanted into mice. IL-18 (10 nM) induced a 4-fold increase in angiogenesis vs the control (p < 0.05). These findings support a novel function for IL-18 as an angiogenic factor in RA and may elucidate a potential therapeutic target for angiogenesis-directed diseases.


Assuntos
Indutores da Angiogênese/fisiologia , Quimiocinas CXC , Interleucina-18/fisiologia , Indutores da Angiogênese/antagonistas & inibidores , Indutores da Angiogênese/imunologia , Animais , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Divisão Celular/imunologia , Linhagem Celular , Inibição de Migração Celular , Movimento Celular/imunologia , Quimiocina CXCL5 , Quimiocinas/fisiologia , Fatores Quimiotáticos/fisiologia , Colágeno/administração & dosagem , Combinação de Medicamentos , Implantes de Medicamento , Endotélio Vascular/citologia , Endotélio Vascular/crescimento & desenvolvimento , Endotélio Vascular/imunologia , Granuloma/fisiopatologia , Humanos , Soros Imunes/farmacologia , Interleucina-18/administração & dosagem , Interleucina-18/antagonistas & inibidores , Interleucina-18/imunologia , Interleucina-8/análogos & derivados , Interleucina-8/fisiologia , Laminina/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/imunologia , Poríferos , Proteoglicanas/administração & dosagem , Receptores de Vitronectina/fisiologia , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Líquido Sinovial/imunologia , Fator de Necrose Tumoral alfa/fisiologia
12.
Undersea Biomed Res ; 17(1): 23-32, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2107615

RESUMO

The effect of hyperbaric oxygen (HBO) on Na+ transport across the isolated toad (Bufo marinus) skin was studied by measuring the transepithelial short-circuit current (ISC) and resistance (R) at 5, 8, and 10 ATA PO2 and 15 ATA normoxia during steady state conditions. The imposition of 5, 8, and 10 ATA PO2 for 2 h resulted in 45, 52, and 85% decrease in ISC, respectively. This decrease in ISC was always accompanied by an increase in R. When amiloride (10(-4) M) was added to the bathing medium, ISC decreased to zero within 15 min regardless of the PO2 level, indicating that the HBO-induced decrease in ISC is caused by an inhibition of amiloride-sensitive Na+ transport. Addition of both superoxide dismutase (SOD) and catalase to the medium bathing both sides of the skin markedly attenuated the HBO effect on ISC and R. Applying HBO to the serosal or mucosal surface independently produced similar effects on ISC. However, the presence of antioxidant enzymes (SOD and catalase) with 10 ATA PO2 prevented the toxic HBO effect only from the serosal side; no protection by these antioxidant enzymes was observed from the mucosal side. These findings are consistent with a view that free radicals are involved in the HBO-induced inhibition of ISC. However, further studies involving the site(s) of radical generation as well as site(s) of toxic action are needed to understand the cellular and molecular mechanism of HBO toxicity.


Assuntos
Oxigenoterapia Hiperbárica/efeitos adversos , Pele/metabolismo , Sódio/metabolismo , Amilorida/farmacologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Bufo marinus , Catalase/farmacologia , Condutividade Elétrica , Feminino , Radicais Livres , Técnicas In Vitro , Masculino , Pele/efeitos dos fármacos , Superóxido Dismutase/farmacologia
13.
J Neurosci Res ; 48(2): 122-7, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9130140

RESUMO

Among the ion channels and pumps activated by growth factor stimulation, K+ channels have been implicated in the growth and proliferation of several cancer cell lines. The role of these channels in central nervous system tumors, however, has not been described. This study used the malignant astrocytoma cell lines U87 and A172. 4-Aminopyridine (4-AP) inhibition of proliferation was dose dependent, and assessment using a TUNEL in situ assay revealed that apoptosis occurred in U87 cells with wild-type p53 but not in A172 cells with mutant p53 (24-hr incubation with mM 4-AP). In patch clamp experiments, we identified two types of K+ currents in both cell lines, a charybdotoxin-sensitive Ca2(+)-activated K+ channel and a 4-AP-sensitive outward rectifier K+ current. The outward rectifier current was blocked by 4-AP in a dose-dependent manner, with half-maximal block occurring at 3.9 mM. The blocking effect of 4 mM 4-AP was noticeable at potentials as low as -65 mV and was statistically significant at -60 mV and above, suggesting that 4-AP-sensitive current is active at physiological potentials. By contrast, charybdotoxin (1 microM) and tetraethylammonium. Cl (2 mM) blocked the Ca2(+)-activated K+ channel in both cell lines but had no appreciable effect on cell growth. Our findings reveal that 4-AP inhibits proliferation and the outward rectifier K+ channel in both U87 and A172 cells. More studies are needed, however, to describe the mechanism by which K+ channels influence proliferation and induce apoptosis.


Assuntos
4-Aminopiridina/farmacologia , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Potássio , Astrocitoma , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/fisiologia
14.
Arthritis Rheum ; 44(5): 1022-32, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11352233

RESUMO

OBJECTIVE: Since it is likely that monocytes utilize chemokines to migrate to the rheumatoid arthritis (RA) joint, we investigated the expression of C-C chemokine receptors (CCR) 1-6 and C-X-C receptor 3 (CXCR3) in the peripheral blood (PB), synovial fluid (SF), and synovial tissue of patients with RA as well as in the PB of normal subjects. METHODS: We compared chemokine receptor expression on CD14+ monocytes from normal PB, RA PB, and RA SF using 2-color flow cytometry. Correlations with patient clinical data were determined. Chemokine and receptor expression were investigated in RA synovial tissue by immunohistochemistry and 2-color immunofluorescence to identify CD68+ macrophages. RESULTS: Most normal PB monocytes expressed CCR1 (87%) and CCR2 (84%), but not CCRs 3, 4, 5, or 6 or CXCR3. RA PB monocytes expressed CCR1 (56%) and CCR2 (76%), with significantly more expressing CCR3 (18%), CCR4 (38%), and CCR5 (17%) compared with normal PB monocytes. Significantly fewer SF monocytes from RA patients expressed CCR1 (17%), CCR2 (24%), and CCR4 (6%) while significantly more expressed CCR3 (35%) and CCR5 (47%) compared with RA and normal PB monocytes; CCR6 and CXCR3 were rarely detected. Clinically, the erythrocyte sedimentation rate was inversely correlated with the expression of CCR1 and CCR4 by RA PB, and CCR5 expression by RA SF was correlated with the SF white blood cell count. CCR1-, CCR2-, and CCR5-immunoreactive cells were found in RA synovial tissue and colocalized with CD68+ macrophages. RA synovial tissue RANTES (regulated upon activation, normally T cell expressed and secreted chemokine)- and monocyte chemoattractant protein 1-immunoreactive cells colocalized with CCR1 and CCR2, respectively, on serial sections. Macrophage inflammatory protein 1alpha (MIP-1alpha) was principally restricted to vascular endothelium, and MIP-1beta+ macrophages were found throughout the sections. CONCLUSION: Monocytes mainly express CCR1 and CCR2 in normal and RA PB, CCR3 and CCR5 in RA PB and RA SF, and CCR4 in RA PB. The differential expression of chemokine receptors suggests that certain receptors aid in monocyte recruitment from the circulation while others are important in monocyte retention in the joint.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Receptores de Quimiocinas/biossíntese , Líquido Sinovial/metabolismo , Membrana Sinovial/metabolismo , Adulto , Quimiocina CCL2/imunologia , Quimiocina CCL2/metabolismo , Quimiocina CCL5/imunologia , Quimiocina CCL5/metabolismo , Feminino , Citometria de Fluxo , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Monócitos/imunologia , Monócitos/metabolismo , Receptores CCR6 , Receptores CXCR3 , Receptores CXCR4/biossíntese , Receptores CXCR4/imunologia , Receptores CXCR5 , Receptores de Quimiocinas/imunologia , Receptores de Citocinas/biossíntese , Receptores de Citocinas/imunologia , Receptores de Interleucina-8A/biossíntese , Receptores de Interleucina-8A/imunologia , Receptores de Interleucina-8B/biossíntese , Receptores de Interleucina-8B/imunologia , Líquido Sinovial/citologia , Líquido Sinovial/imunologia , Membrana Sinovial/citologia , Membrana Sinovial/imunologia
15.
Arthritis Rheum ; 44(7): 1568-81, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11465708

RESUMO

OBJECTIVE: To examine the expression of the novel CX3C chemokine fractalkine (Fkn) and its receptor (CX3CR1) in rheumatoid arthritis (RA) and rat adjuvant-induced arthritis (AIA), a model of RA. METHODS: Immunohistochemistry, flow cytometry, enzyme-linked immunosorbent assay (ELISA), reverse transcriptase-polymerase chain reaction (RT-PCR), and chemotaxis assays were used. RESULTS: In rat AIA, synovial tissue (ST) macrophages, fibroblasts, endothelial cells, and dendritic cells were Fkn immunopositive, whereas lymphocytes did not significantly express Fkn. Significant staining for CX3CR1 was found in ST macrophages, fibroblasts, and dendritic cells, whereas only a small percentage of endothelial cells stained for CX3CR1 in rat AIA. We immunolocalized Fkn to RA ST macrophages, fibroblasts, endothelial cells, and dendritic cells. We also found intense ST macrophage and dendritic cell staining for CX3CR1 in RA ST. Flow cytometry analysis of RA synovial fluid (SF) and peripheral blood revealed a greater percentage of monocytes expressing Fkn and CX3CR1 compared with T cells. By ELISA, we found significantly elevated soluble Fkn (sFkn) levels in RA SF compared with SF from patients with osteoarthritis or other forms of arthritis. By RT-PCR, we found enhanced expression of Fkn and CX3CR1 mRNA on day 18 in rat AIA, a time of pronounced inflammation in the rat joint. Soluble Fkn-depleted RA SF showed significantly decreased chemotactic activity for monocytes compared with sham-depleted RA SF. CONCLUSION: These results indicate that Fkn and its receptor are both expressed in RA and in rat AIA, and that sFkn is up-regulated in RA SF. Furthermore, our data suggest a new role for Fkn in monocyte chemotaxis in the inflamed RA joint.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Quimiocinas CX3C/genética , Proteínas de Membrana/genética , Receptores de Citocinas/genética , Receptores de HIV/genética , Adulto , Animais , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Complexo CD3/análise , Receptor 1 de Quimiocina CX3C , Quimiocina CX3CL1 , Quimiocinas CX3C/análise , Quimiotaxia de Leucócito/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Citometria de Fluxo , Expressão Gênica/imunologia , Humanos , Interleucina-1/farmacologia , Cinética , Receptores de Lipopolissacarídeos/análise , Proteínas de Membrana/análise , Monócitos/química , Monócitos/citologia , Monócitos/imunologia , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos Lew , Receptores de Citocinas/análise , Receptores de HIV/análise , Solubilidade , Líquido Sinovial/imunologia , Líquido Sinovial/metabolismo , Linfócitos T/química , Linfócitos T/imunologia , Tarso Animal/imunologia , Tarso Animal/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/imunologia
16.
Environ Sci Technol ; 22(12): 1402, 1988 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22200463
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