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1.
Contact Dermatitis ; 55(6): 374-5, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17101022

RESUMEN

We present the case of an employee of a chemical production factory who became sensitized to 2-vinylpyridine despite wearing full protective polyvinyl chloride clothing. He developed severe dermatitis at the site of contact, secondary eczematization over the flexures and periungual areas, as well as marked systemic upset. Pyridines are known sensitizers although this reaction pattern has not previously been described.


Asunto(s)
Alérgenos/efectos adversos , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Profesional/diagnóstico , Erupciones por Medicamentos/diagnóstico , Piridinas/efectos adversos , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/patología , Dermatitis Profesional/etiología , Dermatitis Profesional/patología , Diagnóstico Diferencial , Erupciones por Medicamentos/etiología , Erupciones por Medicamentos/patología , Humanos , Rodilla/patología , Masculino , Persona de Mediana Edad , Pruebas del Parche
2.
Biochem Biophys Res Commun ; 328(2): 409-14, 2005 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-15694363

RESUMEN

Angiopoietin-1 (Ang-1) is one of a family of ligands for the Tie-2 receptor which has been demonstrated to be involved in angiogenesis. Little is known about the regulation of Ang-1 gene expression. We have previously demonstrated that TNF-alpha is able to up-regulate the expression of Ang-1 mRNA in synovial fibroblasts. This present study investigated the signal transduction pathways involved in the TNF-alpha induced expression of Ang-1. TNF-alpha signals primarily through the p38, JNK, MAP kinase, and IKK pathways resulting in the activation of the transcription factors AP-1 and NF-kappa B. Experiments with inhibitors and siRNA for these various signal transduction pathways revealed that TNF-alpha stimulation of Ang-1 expression occurs via the NF-kappa B signal transduction pathway.


Asunto(s)
Angiopoyetina 1/metabolismo , Artritis Reumatoide/metabolismo , Fibroblastos/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Membrana Sinovial/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Membrana Sinovial/efectos de los fármacos
3.
J Matern Fetal Neonatal Med ; 13(1): 50-3, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12710857

RESUMEN

OBJECTIVE: To evaluate and quantify the effect of glucocorticosteroid administration on fetal movements and biophysical profile scores. METHODS: Eighteen women at 32-34 weeks' gestation were enrolled. Inclusion criterion was an uncomplicated singleton pregnancy not considered to be at high risk. Patients participated for 3 consecutive days. On day 1, the patients underwent a baseline biophysical profile including a non-stress test followed by a 12-mg betamethasone intramuscular injection. On day 2, the patients received a non-stress test and a second dose of betamethasone. On day 3, a biophysical profile with non-stress test was performed. Maternal counts of fetal kicks were also recorded before, during and after the study period. Each test was conducted at approximately the same time of day to control for diurnal variation. Comparison was made between pre-betamethasone biophysical profile scores and fetal movement and post-betamethasone biophysical profile scores and fetal movement. RESULTS: Biophysical profile scores were reduced in 28% of the study population after betamethasone administration (p < 0.05). Amniotic fluid index on day 3 was decreased from baseline in 72% of patients after betamethasone administration (p < 0.05). Forty-four per cent of patients reported a decrease in fetal movement. Of these patients, 87% had a decreased amniotic fluid index when compared to baseline (p < 0.05). CONCLUSIONS: Fetal movements and breathing motion were decreased after glucocorticosteroid administration, as evidenced by biophysical profile scores and kick counts. The decrease in the amniotic fluid index observed after glucocorticosteroid administration may have been the result of decreased fetal breathing and, therefore, decreased efflux of alveolar fluid into the amniotic sac.


Asunto(s)
Betametasona/administración & dosificación , Movimiento Fetal/efectos de los fármacos , Feto/fisiología , Glucocorticoides/administración & dosificación , Respiración/efectos de los fármacos , Líquido Amniótico/efectos de los fármacos , Líquido Amniótico/metabolismo , Femenino , Humanos , Inyecciones Intramusculares , Embarazo , Valores de Referencia
4.
Curr Opin Pharmacol ; 1(4): 370-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11710735

RESUMEN

Tubulin poisons were first discovered decades ago, but the recent clinical and commercial success of Taxol has led to a renaissance in the search for novel mitotic spindle poisons to treat cancer. Many tubulin poisons have been identified, but few have demonstrated clinical utility. Recent studies have begun to identify the factors that differentiate the efficacy of these agents. In addition, promising alternative approaches to targeting the mitotic spindle have been identified from detailed studies of mitotic regulation and mechanics.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Huso Acromático/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Humanos , Cinesinas/antagonistas & inhibidores , Cinesinas/farmacología , Tubulina (Proteína)/efectos de los fármacos
6.
Occup Environ Med ; 57(2): 106-15, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10711278

RESUMEN

OBJECTIVES: To investigate mortality and cancer morbidity in workers from a factory manufacturing chemicals for the rubber industry. METHODS: The mortality (1955-96) and cancer morbidity experience (1971-92) of a cohort of 2160 male production workers from a chemical factory in north Wales were investigated. All subjects had at least 6 months employment at the factory and some employment in the period 1955-84. Detailed job histories were abstracted from company computerised records and estimates of individual cumulative exposure to 2-mercaptobenzothiazole (MBT) and its derivatives were obtained, with a job exposure matrix derived by a former factory hygienist. Durations of employment in the aniline, phenyl-beta-naphthylamine (PBN) and o-toluidine departments were also calculated. Two analytical approaches were used, indirect standardisation and Poisson regression. RESULTS: Based on serial rates for the general population of England and Wales, observed mortality for the total cohort was close to expectation for all causes (observed (obs) deaths 1131, expected (exp) deaths 1114.5, standardised mortality ratio (SMR) 101), and for all cancers (obs 305, exp 300.2, SMR 102). There was a significant (p < 0.05) excess mortality from cancer of the bladder in the 605 study subjects potentially exposed to one or more of the four chemicals being investigated (obs 9, exp 3.25, SMR 277, 95% confidence interval (95% CI) 127 to 526). This excess was dependent primarily on deaths occurring > 20 years after first exposure in those who started employment before 1955 (obs 7, exp 1.25, SMR 560, 95% CI 225 to 1154, p < 0.001). There were 30 subjects in the total study cohort who, on the basis of death certificates or cancer registration particulars, had had malignant bladder cancer. In separate analyses of the four exposure history variables (after adjustment for age), Poisson regression showed significant positive trends for risk of notification of bladder cancer increasing with cumulative duration of employment in the PBN (p < 0.001) and o-toluidine departments (p < 0.01); similar findings were not obtained for cumulative exposure to MBT or for duration of employment in the aniline department. In a simultaneous analysis of all four chemical exposure variables, a significant positive trend remained for duration of employment with exposure to PBN (p < 0.05). Further analyses of all cases of bladder cancer (malignant and benign diagnoses) used employment histories lagged by 15 years; similar findings were obtained. CONCLUSIONS: It seems likely that some members of this cohort have had occupational bladder cancer. Confident interpretation is difficult because of small numbers in the exposed subcohorts, relatively crude measures of exposure assessment for the four chemicals under study, and presence of unconsidered potential chemical confounders. The simplest interpretation of the findings about bladder cancer may be that PBN (or a chemical reagent or chemical intermediate associated with its production at this factory in the 1930s and 1940s) is a bladder carcinogen. Priority should be given, however, to obtaining information on the cancer experience of other working populations exposed to PBN or to o-toluidine.


Asunto(s)
2-Naftilamina/efectos adversos , Compuestos de Anilina/efectos adversos , Neoplasias/epidemiología , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Tiazoles/efectos adversos , Toluidinas/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Benzotiazoles , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Goma , Gales/epidemiología
7.
Cancer Res ; 60(3): 566-72, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10676638

RESUMEN

Many cancer therapies cause DNA damage to effectively kill proliferating tumor cells; however, a major limitation of current therapies is the emergence of resistant tumors following initial treatment. Cell cycle checkpoints are involved in the response to DNA damage and specifically prevent cell cycle progression to allow DNA repair. Tumor cells can take advantage of the G2 checkpoint to arrest following DNA damage and avoid immediate cell death. This can contribute to acquisition of drug resistance. By abrogating the G2 checkpoint arrest, it may be possible to synergistically augment tumor cell death induced by DNA damage and circumvent resistance. This requires an understanding of the molecules involved in regulating the checkpoints. Human Chk1 is a recently identified homologue of the Schizosaccharomyces pombe checkpoint kinase gene, which is required for G2 arrest in response to DNA damage. Chk1 phosphorylates the dual specificity phosphatase cdc25C on Ser-216, and this may be involved in preventing cdc25 from activating cdc2/cyclinB and initiating mitosis. To further study the role of Chk1 in G2 checkpoint control, we identified a potent and selective indolocarbazole inhibitor (SB-218078) of Chk1 kinase activity and used this compound to assess cell cycle checkpoint responses. Limited DNA damage induced by gamma-irradiation or the topoisomerase I inhibitor topotecan was used to induce G2 arrest in HeLa cells. In the presence of the Chk1 inhibitor, the cells did not arrest following gamma-irradiation or treatment with topotecan, but continued into mitosis. Abrogation of the damage-arrest checkpoint also enhanced the cytotoxicity of topoisomerase I inhibitors. These studies suggest that Chk1 activity is required for G2 arrest following DNA damage.


Asunto(s)
Alcaloides/farmacología , Daño del ADN , Inhibidores Enzimáticos/farmacología , Proteínas Quinasas , Ciclo Celular/efectos de los fármacos , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Fase G2/efectos de los fármacos , Humanos , Inhibidores de Proteínas Quinasas , Proteínas de Schizosaccharomyces pombe , Inhibidores de Topoisomerasa I , Topotecan/farmacología
8.
J Reprod Med ; 44(4): 339-45, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10319303

RESUMEN

OBJECTIVE: To evaluate the feasibility for an institution to offer laparoscopic supracervical hysterectomy as a cost-effective alternative to total abdominal hysterectomy (TAH) in a managed care environment. STUDY DESIGN: Retrospective study in which 138 consecutive laparoscopic supracervical hysterectomies performed between December 1992 and May 1996 were reviewed and compared to 354 consecutive TAHs performed during the same period. Operating time, use of operative room supplies, length of stay and actual total, fixed and variable costs of each case were calculated for the entire hospital stay and for each hospital cost center. Differences between costs were analyzed by ANCOVA using age, patient weight, specimen weight and number of operative procedures performed at the time of hysterectomy as covariants. RESULTS: The mean operative room time was significantly greater for laparoscopic supracervical hysterectomy than for TAH (167.4 [SD 51.2] vs. 103 minutes [30.3, P < .001]). In contrast, length of stay was significantly shorter for laparoscopic supracervical hysterectomy than for TAH (0.8 [SD 1.1] vs. 3.4 days [.9, P < .001]). The adjusted mean costs of both operative room time and supplies were significantly higher for laparoscopic supracervical hysterectomy than for TAH (P < .001). In contrast, the mean cost of length of stay for laparoscopic supracervical hysterectomy was significantly lower (P < .001). However, the adjusted mean total costs of the entire hospital stay were not significantly different: $2,716 for laparoscopic supracervical hysterectomy vs. $2,702 for TAH (F = .7, P = .8). The absence of significant differences between procedures resulted from our limited use of disposable supplies (no automated stapling device) and from shorter lengths of stay, which compensated well for the higher operative room costs of time and supplies incurred with laparoscopic supracervical hysterectomy. CONCLUSION: Laparoscopic supracervical hysterectomy is, at least in the short term, a cost-effective alternative to TAH in a managed care environment.


Asunto(s)
Costos de Hospital/estadística & datos numéricos , Hospitales Comunitarios/economía , Histerectomía/economía , Laparoscopía/economía , Adulto , Análisis de Varianza , Análisis Costo-Beneficio , Estudios de Factibilidad , Humanos , Histerectomía/instrumentación , Laparoscopios , Tiempo de Internación/economía , Programas Controlados de Atención en Salud/economía , Pennsylvania , Estudios Retrospectivos , Factores de Tiempo
9.
Can J Urol ; 6(3): 812-818, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11178607

RESUMEN

PURPOSE: To analyze the predictive value of early postnatal ultrasonography in congenital hydronephrosis. SUBJECTS AND METHODS: A retrospective study was conducted of 77 affected infants at our institution. All postnatal ultrasound studies were evaluated using 2 classification systems, the Anterior-Posterior Diameter (APD) system and the Society for Fetal Urology (SFU) system. Each study was compared to subsequent ultrasound examinations, renal scans, and to clinical outcome. RESULTS: There were 115 dilated renal units. Fifteen (13%) underwent intervention; all initially had high grade hydronephrosis on both classification systems. One hundred renal units (87%) were managed conservatively; 47 had low grade hydronephrosis and only 18 had high grade hydronephrosis on both systems. CONCLUSIONS: Using both the APD and the SFU classification systems together on the initial postnatal ultrasound is superior to using either method on its own, and the combined system enables us to predict the outcome of infants with congenital hydronephrosis.

10.
Biochim Biophys Acta ; 1392(1): 145-52, 1998 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-9593866

RESUMEN

Chronic inflammatory diseases are often accompanied by intense angiogenesis. A model of inflammatory angiogenesis is the murine air pouch granuloma which has a hyperangiogenic component. Proinflammatory lipid mediator generation is also a hallmark of chronic inflammation and the role of endogenous production of these mediators in angiogenesis is not known. The 14 kDa phospholipase A2 (PLA2) deacylates phospholipid, liberating arachidonic acid, which is used for leukotriene production, and lysophospholipid, which can drive the production of platelet-activating factor (PAF). Therefore, SB 203347, an inhibitor of the 14 kDa PLA2, zileuton, an inhibitor of 5-lipoxygenase, and Ro 24-4736 a PAF receptor antagonist were evaluated for their effects in the murine air pouch granuloma. SB 203347 reduced both LTB4 and PAF, but not PGD2 levels measured in the day 6 granuloma. This correlated with a significant reduction in angiogenesis. Zileuton reduced LTB4 levels as expected, but did not significantly inhibit angiogenesis, whereas Ro 24-4736 potently reduced angiogenesis. These data support the hypothesis that PAF, and to a lesser extent leukotrienes contribute to the angiogenic phenotype in chronic inflammation.


Asunto(s)
Granuloma/patología , Mediadores de Inflamación/metabolismo , Neovascularización Patológica , Factor de Activación Plaquetaria/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Femenino , Granuloma/metabolismo , Hidroxiurea/análogos & derivados , Hidroxiurea/farmacología , Leucotrienos/metabolismo , Ratones , Ratones Endogámicos BALB C , Fenantridinas/farmacología , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A2 , Factor de Activación Plaquetaria/antagonistas & inhibidores , Sulfonamidas/farmacología , Triazinas/farmacología
11.
J Pharmacol Exp Ther ; 284(2): 687-92, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9454815

RESUMEN

Chronic inflammatory diseases often are accompanied by intense angiogenesis, supporting the destructive proliferation of inflammatory tissues. A model of inflammatory angiogenesis is the murine air pouch granuloma, which has a hyperangiogenic component. In this model, we explored the regulation of inflammatory angiogenesis using SB 220025, a specific inhibitor of human p38 mitogen-activated protein (MAP) kinase, with an IC50 value of 60 nM and 50- to 1000-fold selectivity vs. other kinases tested. In vivo, this compound reduced the lipopolysaccharide-induced production of tumor necrosis factor at an ED50 value of 7.5 mg/kg. In the inflammatory angiogenesis model, over the course of granuloma development, we observed elevated levels of interleukin-1beta and tumor necrosis factor-alpha during the chronic inflammatory phase when intense angiogenesis occurs. SB 220025 at 30 mg/kg b.i.d. p.o. was able to greatly reduce the expression of these cytokines and inhibit angiogenesis by approximately 40%. To further study the effects of p38/CSBP MAP kinase inhibition in angiogenesis-dependent chronic inflammatory disease, SB 220025 was tested in murine collagen-induced arthritis. In this model, SB 220025 was able to prevent the progression of established arthritis. Thus, this p38/CSBP MAP kinase inhibitor, which can reduce inflammatory cytokine production and inhibit angiogenesis, is an effective treatment for chronic proliferative inflammatory disease.


Asunto(s)
Antiinflamatorios/farmacología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Imidazoles/farmacología , Proteínas Quinasas Activadas por Mitógenos , Neovascularización Patológica/prevención & control , Pirimidinas/farmacología , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Granuloma/patología , Inflamación/fisiopatología , Interleucina-1/biosíntesis , Lipopolisacáridos , Ratones , Neovascularización Patológica/patología , Factores de Tiempo , Factor de Necrosis Tumoral alfa/biosíntesis , Proteínas Quinasas p38 Activadas por Mitógenos
12.
J Pharmacol Exp Ther ; 283(2): 955-61, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9353419

RESUMEN

Exposure of human rheumatoid synovial fibroblasts (RSF) to interleukin 1beta (IL-1beta) results in the coordinate up-regulation of 85-kDa phospholipase A2 (PLA2) and mitogen-inducible cyclooxygenase (COX II) and subsequent biosynthesis of prostaglandin E2 (PGE2). We have recently demonstrated, through the use of oligonucleotide decoys and antisense, the participation of the proinflammatory transcription factor, nuclear factor kappaB (NFkappaB), in the regulation of the prostanoid-metabolizing enzymes. Hymenialdisine, a marine natural product has recently been characterized as an inhibitor of NFkappaB activation and exposure of IL-1-stimulated RSF-inhibited PGE2 production in a concentration-dependent manner (IC50 approximately 1 microM). Alternatively, both an analog, aldisine, and the protein kinase C inhibitor, RO 32-0432, were without affect. Direct action of hymenialdisine on IL-1-induced NFkappaB activation was demonstrated by a significant reduction (approximately 80%) in NFkappaB binding to the classical kappaB consensus motif (as assessed by electrophoretic mobility shift assay) and inhibition of stimulated p65 migration from the cytosol of treated cells (as assessed by Western analysis). Consistent with the role of NFkappaB in the transcriptional regulation of COX II and 85-kDa PLA2, hymenialdisine-treated RSF did not transcribe the respective mRNAs in response to IL-1. This led to reductions in their respective protein levels and subsequent reductions in the ability to produce PGE2. Specificity of action is suggested as IL-1-stimulated interleukin-8 (IL-8) production, which is known to be an NFkappaB-regulated event, was also inhibited by hymenialdisine, whereas IL-1-induced production of vascular endothelial growth factor, a non-NFkappaB-regulated gene, was not affected by exposure to hymenialdisine. Taken together, hymenialdisine inhibits IL-1-stimulated-RSF PGE2 formation acting predominately through modulation of NFkappaB activation and offers an interesting novel tool to evaluate the role of NFkappaB in inflammatory disease.


Asunto(s)
Artritis Reumatoide/metabolismo , Azepinas/farmacología , Dinoprostona/biosíntesis , Interleucina-1/farmacología , FN-kappa B/antagonistas & inhibidores , Pirroles/farmacología , Membrana Sinovial/metabolismo , Adulto , Células Cultivadas , Factores de Crecimiento Endotelial/biosíntesis , Humanos , Interleucina-8/biosíntesis , Linfocinas/biosíntesis , Fosfolipasas A/metabolismo , Fosfolipasas A2 , Prostaglandina-Endoperóxido Sintasas/metabolismo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
15.
J Rheumatol ; 24(7): 1253-9, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9228120

RESUMEN

OBJECTIVE: To study the mechanism by which hypoxia and inflammatory cytokines mediate angiogenesis in the rheumatoid pannus through their effects on the fibroblast-like type B synoviocyte, the major cell type of normal synovia. METHODS: Fibroblasts were prepared from synovial tissue of healthy and diseased individuals, and cultured in the presence of various stimuli. The expression of vascular endothelial growth factor (VEGF) was assessed by ELISA and reverse transcription polymerase chain reaction. RESULTS: Unlike normal fibroblasts, synovial fibroblasts from rheumatoid arthritis (RA) and osteoarthritis constitutively secreted significant levels of VEGF, which is known to act directly on endothelial cells. VEGF secretion was further inducible by both hypoxia and interleukin 1beta (IL-1beta) and these increases were additive. In contrast, tumor necrosis factor alpha was unable to induce VEGF expression. CONCLUSION: Under hypoxia or IL-1 stimulation, conditions common to the inflamed synovium, type B synoviocytes secrete increased levels of VEGF, which is likely to act on nearby endothelia, promoting angiogenesis. The constitutive expression of VEGF in rheumatoid synovial fibroblasts may reflect an altered phenotype involved in the pathology of RA.


Asunto(s)
Factores de Crecimiento Endotelial/metabolismo , Interleucina-1/farmacología , Linfocinas/metabolismo , Membrana Sinovial/citología , Empalme Alternativo/fisiología , Artritis Reumatoide/metabolismo , Hipoxia de la Célula/fisiología , Células Cultivadas , Factores de Crecimiento Endotelial/genética , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Expresión Génica/fisiología , Humanos , Interleucina-8/metabolismo , Linfocinas/genética , Neovascularización Fisiológica/efectos de los fármacos , Osteoartritis/metabolismo , Membrana Sinovial/metabolismo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
FASEB J ; 11(6): 457-65, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9194526

RESUMEN

Angiogenesis is the growth of new blood vessels from existing ones. It is an important aspect of new tissue development, growth, and tissue repair. It is also a component of many diseases including cancer, blindness, and chronic inflammation such as rheumatoid arthritis (RA) and psoriasis. There is considerable evidence to suggest that angiogenesis and chronic inflammation are codependent; recent studies have begun to reveal the nature of this link, which involves both augmentation of cellular infiltration and proliferation and overlapping roles of regulatory growth factors and cytokines. Through these studies, we have begun to understand the codependence of chronic inflammation and angiogenesis, the potential benefits of targeting angiogenesis in the treatment of chronic inflammation, and of targeting chronic inflammation to affect angiogenesis.


Asunto(s)
Inflamación , Neovascularización Patológica , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Humanos , Inflamación/tratamiento farmacológico , Inflamación/etiología , Inflamación/fisiopatología , Modelos Biológicos , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/etiología , Neovascularización Patológica/fisiopatología
18.
J Biol Chem ; 271(49): 31496-501, 1996 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-8940164

RESUMEN

Interleukin 1beta (IL-1beta) up-regulates human rheumatoid synovial fibroblast (RSF) 85-kDa phospholipase A2 (PLA2) and mitogen-inducible cyclooxygenase (COX) II. Promoter regions for these genes contain a motif that closely resembles the "classic" NFkappaB consensus site. Immunoblot analysis identified NFkappaB1 (p50), RelA (p65), and c-Rel in RSF. Upon IL-1beta-stimulation, p65 and c-Rel but not p50 protein levels were reduced suggesting nuclear translocation. IL-1beta-induced RSF nuclear extracts contained a p65-containing complex, which bound to the classical NFkappaB consensus motif. An NFkappaB classical oligonucleotide decoy produced a concentration-dependent decrease in IL-1-stimulated PGE2 production (IC50 = approximately 2 microM), indicating a role of NFkappaB. Utilization of antisense technology showed that p65 but not p50 or c-Rel mediated IL-1beta-stimulated PGE2 formation. Treated RSF could not transcribe COX II or 85-kDa PLA2 mRNA, which reduced their respective proteins. Interestingly, stimulated IL-8 production was not inhibited by the classical NFkappaB decoy but was reduced by treatment with antisense to both p65 and c-Rel supporting preferential binding of c-Rel-p65 to the "alternative" IL-8 kappaB motif. Taken together, these data provide the first direct evidence for a role of p65 in COX II and 85-kDa PLA2 gene induction and support the IL-1 activation and participation of distinct NFkappaB protein dimers in RSF prostanoid and IL-8 formation.


Asunto(s)
Artritis Reumatoide/metabolismo , Dinoprostona/biosíntesis , Interleucina-1/farmacología , FN-kappa B/metabolismo , Membrana Sinovial/efectos de los fármacos , Northern Blotting , Ciclooxigenasa 2 , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Interleucina-8/biosíntesis , Isoenzimas/metabolismo , Proteínas de la Membrana , FN-kappa B/farmacología , Oligonucleótidos Antisentido/farmacología , Fosfolipasas A/metabolismo , Fosfolipasas A2 , Prostaglandina-Endoperóxido Sintasas/metabolismo , Factor de Transcripción ReIA , Regulación hacia Arriba/efectos de los fármacos
19.
J Am Med Inform Assoc ; 3(3): 208-15, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8723611

RESUMEN

OBJECTIVE: To examine the relationships among different performance scores for each of four diagnostic decision support systems (DDSSs). DESIGN: Intercorrelations among seven performance scores on a set of 105 cases for each of four DDSSs (DXplain, Iliad, Meditel, QMR) were computed. METHODS: The performance scores for each case reflected: 1) presence or absence of the case diagnosis in the DDSS knowledge base; 2) presence or absence of the correct diagnosis anywhere on the DDSS diagnosis list; 3) presence or absence of the correct diagnosis in the top ten diagnoses; 4) relevance of the DDSS diagnosis list; 5) comprehensiveness of the DDSS diagnosis list; 6) whether the DDSS suggested additional diagnoses to the experts' list; and 7) the length of the DDSS diagnosis list. RESULTS: For all DDSSs, the two Correct Diagnosis scores (top ten and total list) were significantly related: 1) to the presence of the correct diagnosis in the knowledge base; 2) to the Comprehensiveness score; and 3) to each other. There were significant differences among the four DDSSs on the magnitude and/or direction of the relationships between: 1) the two Correct Diagnosis scores; 2) the Relevance and Length scores; and 3) the Relevance and Additional Diagnoses scores. CONCLUSION: The production of a correct diagnosis for a given case is not related to the number of diagnoses suggested by the DDSS and, across different DDSSs, is not consistently related to other measures of performance. These data indicate that multiple measures are needed to fully describe the performance of a DDSS.


Asunto(s)
Técnicas de Apoyo para la Decisión , Diagnóstico por Computador , Algoritmos , Inteligencia Artificial , Teorema de Bayes , Diagnóstico , Sistemas Especialistas , Humanos
20.
Cytokine ; 8(3): 206-13, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8833035

RESUMEN

The extracellular domain of the type I Interleukin-1 receptor (sIL-1R) was expressed in Drosophila S2 cells as a secreted 43 kDa glycoprotein, as evidenced by its binding to Concanavalin A and enzymatic deglycosylation. sIL-1R bound IL-1 beta with a K(D) of 2 nM as determined by competition ELISA. N-Glycanase treated sIL-1R had a C. 100 fold lower affinity than glycosylated sIL-1R for IL-1 beta, suggesting that glycosylation is a key component of the IL-1 beta/IL-1 receptor interaction. Crosslinking of sIL-1R to (125)I-IL-1 beta could be competed with unlabelled IL-1 alpha, IL-1 beta, IL-1 receptor antagonist (IL-1ra), and a mutant of IL-1 (Th9Gly) which has reduced bioactivity but wild type receptor binding affinity. Limited proteolysis of sIL-1R in the presence of IL-1 alpha, IL-1 beta, IL-1ra, and Thr9Gly IL-1 beta with several different proteases followed by analysis of sIL-1R by Western blot was used to assess the effect of binding on sIL-1R conformation. While some proteases showed no differences in cleavage patterns or sensitivity between free and bound sIL-1R, others showed differences in either cleavage sites or sensitivity with different ligands. This implies that upon ligand binding there is a conformational change in the receptor which is sensitive to the particular ligand bound, and hence has implications for the ability of different ligands to trigger responses after binding to receptor.


Asunto(s)
Interleucina-1/metabolismo , Conformación Proteica , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Animales , Sitios de Unión , Línea Celular , Clonación Molecular , Reactivos de Enlaces Cruzados , Drosophila melanogaster , Endopeptidasas , Glicosilación , Humanos , Ligandos , Hígado/metabolismo , Receptores Tipo I de Interleucina-1 , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Especificidad por Sustrato , Transfección
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