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1.
J Clin Invest ; 83(1): 336-42, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2536045

RESUMEN

We investigated the actions of endothelin in anesthetized rats and cultured mesangial cells. Intravenous infusion of endothelin (10 pmol/min) decreased renal blood flow by 44% at 20 min without changing arterial pressure, which subsequently rose significantly from 124 +/- 3 to 133 +/- 4 mmHg over 60 min. Micropuncture during the nonhypertensive period revealed increases in afferent (65%) and efferent (82%) arteriolar resistances, thereby reducing nephron plasma flow rate. The glomerular ultrafiltration coefficient (Kf) fell from 0.097 +/- 0.035 to 0.031 +/- 0.011 nl/(s.mmHg) as did single nephron filtration rate (41 +/- 3 to 19 +/- 3 nl/min). Addition of 5 nM endothelin to mesangial cells plated on a silicone rubber substrate increased the intensity and number of tension-generated wrinkles, and caused their reappearance in forskolin prerelaxed cells. 20-30 s following exposure of fura-2 loaded mesangial cells to 10 nM endothelin, single cell intracellular calcium concentration ([Ca]i) increased from a mean baseline value of 66 +/- 11 (SE) to a peak of 684 +/- 250 nM (P less than 0.05) followed by a sustained elevation at 145 +/- 42 nM. Anion exchange HPLC revealed rapid (15 s) and dose-dependent stimulation of inositol 1,4,5-trisphosphate (IP3) generation following exposure of [3H]myoinositol preloaded mesangial cells to 10-100 nM endothelin. Endothelin also led to intracellular alkalinization of 2'7'-bis(2-carboxy-ethyl)-5(and-6)carboxyfluorescein (BCECF)-loaded mesangial cells and its addition was associated with dramatic augmentation of mitogenic activity. Thus, endothelin exerts potent constrictor effects on renal arterioles which precede its systemic hypertensive action. It lowers Kf and contracts mesangial cells, likely through stimulation of IP3 generation and elevation of [Ca]i. It is a potent mesangial cell mitogen. These studies define functional responses and signal transduction pathways for endothelin in the rat kidney and propose a potential role for this peptide in the control of mesangial cell function, glomerular filtration rate, and renal vascular tone.


Asunto(s)
Mesangio Glomerular/citología , Glomérulos Renales/irrigación sanguínea , Riñón/irrigación sanguínea , Péptidos/farmacología , Transducción de Señal , Animales , Endotelinas , Concentración de Iones de Hidrógeno , Masculino , Fosfatidilinositoles/metabolismo , Ratas , Timidina/metabolismo
2.
J Clin Invest ; 99(5): 1130-7, 1997 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9062372

RESUMEN

Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem. Reporter gene activity directed by any of the mutant forms of the transcription factor binding region was significantly (P < 0.05) less effective than the activity driven by the wild type transcription factor binding region. Electrophoretic mobility shift assays (EMSAs) demonstrated the capacity of wild type and mutant transcription factor binding regions to bind nuclear extracts from human umbilical vein endothelial cells (HUVECs). These data are consistent with a family of mutations in the 5-LO gene that can modify reporter gene transcription possibly through differences in Sp1 and Egr-1 transactivation.


Asunto(s)
Asma/genética , Genes Reporteros/genética , Proteínas Inmediatas-Precoces , Lipooxigenasa/genética , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Transcripción Genética/genética , Alelos , Secuencia de Bases , Codón Iniciador , Cartilla de ADN , Proteínas de Unión al ADN/genética , Hipersensibilidad a las Drogas/genética , Proteína 1 de la Respuesta de Crecimiento Precoz , Exones , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Plásmidos , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo Conformacional Retorcido-Simple , Recombinación Genética , Proteínas Oncogénicas de Retroviridae/genética , Análisis de Secuencia de ADN , Eliminación de Secuencia
3.
J Natl Cancer Inst ; 86(9): 681-7, 1994 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-8158699

RESUMEN

BACKGROUND: Aberrations of the p53 gene (also known as TP53) frequently lead to the synthesis of mutant proteins that accumulate in the nuclei and/or cytoplasm of neoplastic cells. Intracellular p53 protein accumulation may be an unfavorable prognostic parameter in breast, lung, ovarian, gastric, and colorectal cancers. Specific classes of p53 gene mutations, assayed by characteristic subcellular p53 protein accumulation patterns, may be useful prognostic indicators. PURPOSE: The prognostic value of nuclear and cytoplasmic p53 protein accumulation in the tumor cells of patients with colorectal carcinoma was studied. METHODS: Antibodies PAb 1801 and CM1 were used for immunocytochemical assay of nuclear and cytoplasmic p53 protein accumulation in a retrospective series of colorectal carcinoma samples obtained from 206 patients who were followed for at least 5 years. Results were correlated with the following clinicopathologic parameters: patient sex and age; tumor site, stage, and grade; and DNA ploidy status of the tumors. Overall survival and disease-free survival were analyzed with the Kaplan-Meier method. Differences in distributions were analyzed using the Mantel-Cox method. Multivariate analysis was performed with the Cox proportional hazards model. RESULTS: Immunostaining with PAb 1801 revealed nuclear p53 accumulation in 46% (95) of 206 cases, whereas CM1 immunostaining of 197 cases showed nuclear and cytoplasmic p53 accumulation in 33% (65 cases) and 50% (99 cases) of the cases, respectively. In univariate analysis, both nuclear p53PAb 1801 and cytoplasmic p53CM1 protein accumulations were significantly associated with poor overall survival (P = .0198 and P = .0017, respectively) and with disease-free survival (P = .004 and P = .0016, respectively). When patients were analyzed according to site of their tumors, nuclear p53PAb 1801 protein accumulation was statistically significant only in the right colon (P = .027), whereas cytoplasmic p53CM1 protein accumulation was statistically significant in the left colon and rectum (P = .0016). In multivariate analysis, only cytoplasmic p53CM1 protein accumulation was associated with poor overall survival and with disease-free survival (P = .006 and P = .002, respectively). With the addition of DNA ploidy status, however, cytoplasmic p53CM1 protein accumulation remained significant only for disease-free survival (P = .035). In patients with tumors of the left colon and rectum, cytoplasmic p53CM1 protein accumulation was the most significant prognostic indicator for overall survival (P = .007) and disease-free survival (P = .002) after disease stage. CONCLUSION: Cytoplasmic p53CM1 protein accumulation, but not nuclear p53PAb 1801 protein accumulation, is an independent prognostic parameter in patients with colorectal carcinomas. IMPLICATIONS: Cytoplasmic p53CM1 accumulation may be a useful indicator of patients at high risk for disease recurrence who may benefit from aggressive adjuvant therapy.


Asunto(s)
Adenocarcinoma/metabolismo , Núcleo Celular/metabolismo , Neoplasias Colorrectales/metabolismo , Citoplasma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , ADN de Neoplasias/genética , Femenino , Humanos , Inmunohistoquímica , Masculino , Estadificación de Neoplasias , Ploidias , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Estadística como Asunto , Análisis de Supervivencia
4.
Biochim Biophys Acta ; 1095(3): 236-42, 1991 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-1659906

RESUMEN

Recent evidence suggests that the hydrolysis of phosphatidylcholine (PC) by phospholipase D (PLD) may mediate superoxide anion (O2-) production in human neutrophils. To define the role of the PC-specific PLD products phosphatidic acid (PA) and diacylglycerol (DAG) in O2- production in response to agonists which activate the PLD pathway, we blocked the metabolism of PA to DAG with propranolol, an inhibitor of PA phosphohydrolase. Propranolol (150 microM) enhanced the production of O2- in response to the receptor agonists n-formyl-methionyl-leucyl-phenylalanine (FMLP, 292 +/- 94% of controls), platelet-activating factor (PAF, 932 +/- 215%) and leukotriene B4 (LTB4, 1305 +/- 475%). In the presence of propranolol, total O2- production in response to PAF and LTB4, which are potent priming stimuli but very weak direct agonists, was similar to that obtained with FMLP. IN contrast, responses to receptor-independent agonists phorbol myristate acetate (PMA) and ionomycin were inhibited (81 +/- 8% and 87 +/- 5% inhibition, respectively). The effects of propranolol were demonstrable in the absence of cellular calcium and were shared by both stereoisomers of the drug. These data are consistent with the hypothesis that PA produced through the hydrolysis of PC by PLD is an important mediator of O2- production in response to receptor-dependent agonists. However, the inhibitory effects of propranolol on receptor-independent stimuli suggest that PA generated through the PLD pathway plays a different role in the signal transduction mechanisms of these agonists or that propranolol may have additional effects beyond inhibition of PA phosphohydrolase.


Asunto(s)
Neutrófilos/efectos de los fármacos , Fosfolipasa D/fisiología , Propranolol/farmacología , Estallido Respiratorio/efectos de los fármacos , Superóxidos/metabolismo , Calcio/farmacología , Humanos , Técnicas In Vitro , Ionomicina/farmacología , Isomerismo , Leucotrieno B4/farmacología , N-Formilmetionina Leucil-Fenilalanina/farmacología , Factor de Activación Plaquetaria/farmacología , Propranolol/química , Transducción de Señal , Acetato de Tetradecanoilforbol/farmacología , Factores de Tiempo
5.
Biochim Biophys Acta ; 1472(1-2): 359-67, 1999 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-10572957

RESUMEN

We have investigated the effects of a sinusoidal 60 Hz magnetic field on free radical (superoxide anion) production, degranulation (beta-glucuronidase and lysozyme release) and viability in human neutrophils (PMNs). Experiments were performed blindly in very controlled conditions to examine the effects of a magnetic field in resting PMNs and in PMNs stimulated with a tumor promoter: phorbol 12-myristate 13-acetate (PMA). Exposure of unstimulated human PMNs to a 60 Hz magnetic field did not affect the functions examined. In contrast, exposure of PMNs to a 22 milliTesla (mT), 60 Hz magnetic field induced significant increases in superoxide anion (O2-) production (26.5%) and in beta-glucuronidase release (53%) when the cells were incubated with a suboptimal stimulating dose of PMA. Release of lysozyme and lactate dehydrogenase was unchanged by the magnetic field, whether the cells were stimulated or not. A 60 Hz magnetic field did not have any effect on O2- generation by a cell-free system xanthine/xanthine oxidase, suggesting that a magnetic field could upregulate common cellular events (signal transduction) leading to O2- generation and beta-glucuronidase release. In conclusion, exposure of PMNs to a 22 mT, 60 Hz magnetic field potentiates the effect of PMA on O2- generation and beta-glucuronidase release. This effect could be the result of an alteration in the intracellular signaling.


Asunto(s)
Magnetismo , Activación Neutrófila , Neutrófilos/efectos de la radiación , Adulto , Apoptosis , Degranulación de la Célula , Sistema Libre de Células , Glucuronidasa/metabolismo , Humanos , Mediciones Luminiscentes , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Neutrófilos/metabolismo , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacología
6.
Biochim Biophys Acta ; 1336(2): 243-53, 1997 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-9305796

RESUMEN

Phosphorylation of components of the neutrophil NADPH oxidase plays a critical role in activation and maintenance of superoxide anion (O2-) generation. To investigate the role of dephosphorylation by phosphatases in regulating O2- production, human neutrophils were treated with calyculin A, a potent inhibitor of protein phosphatases 1 and 2A, prior to stimulation. Calyculin A alone did not stimulate O2- production. However, neutrophils exposed to 50 nM calyculin A and the chemotactic peptide formyl-met-leu-phe (FMLP, 100 nM) displayed markedly enhanced O2- production in comparison to cells stimulated with FMLP alone (28.63 +/- 7.00 versus 8.69 +/- 3.69 nmol O2-/1.5 x 10(6) neutrophils/5 min, respectively, n = 18, p < 0.001), with an increased duration of O2- production. In contrast, phosphatase-inhibition decreased oxidative responsiveness to phorbol myristate acetate (PMA, > or = 16 nM). We next examined the effect of calyculin A on products of the phosphatidylcholine-specific phospholipase D (PLD) pathway by assaying the mass levels of phosphatidic acid (PA), choline and diacylglycerol (DAG). Calyculin A increased both PA and choline production to 224 +/- 28% and 315 +/- 61% of FMLP-stimulated controls, respectively (p < 0.01, n = 7) without significantly increasing DAG. Also, membrane protein kinase C activity increased more than 10-fold in FMLP-stimulated cells exposed to calyculin A but decreased in cells stimulated with PMA following calyculin A pre-treatment. These results suggest that phosphatases exert variable and stimulus-dependent effects on pathways leading to O2- production. Further, it appears that phospholipase D activity and PA generation represent important steps in the pathway for NADPH activation triggered by FMLP.


Asunto(s)
Neutrófilos/metabolismo , Monoéster Fosfórico Hidrolasas/fisiología , Superóxidos/metabolismo , Adulto , Humanos , Toxinas Marinas , N-Formilmetionina Leucil-Fenilalanina/farmacología , NADPH Oxidasas/metabolismo , Oxazoles/farmacología , Ácidos Fosfatidicos/metabolismo , Fosfolipasa D/efectos de los fármacos , Fosfolipasa D/metabolismo , Fosforilación , Proteína Quinasa C/efectos de los fármacos , Proteína Quinasa C/fisiología , Estaurosporina/farmacología , Acetato de Tetradecanoilforbol/farmacología
7.
Biochim Biophys Acta ; 969(3): 289-96, 1988 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-2897209

RESUMEN

The aggregation of gel-filtered rabbit platelets by 50 microM ADP was inhibited by a labile factor produced by suspensions of cultured bovine pulmonary artery endothelial cells. Inhibition of aggregation occurred when indomethacin-treated endothelial cells (6.10(5) per ml) and rabbit platelets (3.2.10(8) per ml) were incubated together. This anti-aggregatory activity was characterized as similar to endothelium-derived relaxing factor (EDRF) in that it was unstable at neutral pH and by its inhibition by hemoglobin. The activity was unaffected by treatment of the platelets and endothelial cells with the cyclooxygenase inhibitor, indomethacin, and by the lipoxygenase inhibitor, BW755c. In association with the anti-aggregatory activity, the levels of cyclic GMP were elevated 4-fold. The effect of the EDRF-like product on the levels of cyclic nucleotides was mimicked by treatment of platelets with sodium nitroprusside, an activator of soluble guanylate cyclase; sodium nitroprusside had no measurable effect on the levels of cyclic nucleotides of endothelial cells. We conclude that a factor with the properties of EDRF inhibits platelet aggregation, and that this is associated with an activation of guanylate cyclase as in smooth muscle. Thus, EDRF may exert an inhibitory effect on platelets in a manner analogous to its actions on vascular smooth muscle.


Asunto(s)
Productos Biológicos/farmacología , Endotelio Vascular/fisiología , Guanilato Ciclasa/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/farmacología , Animales , Productos Biológicos/antagonistas & inhibidores , Bovinos , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Hemoglobinas/farmacología , Óxido Nítrico , Nucleótidos Cíclicos/metabolismo , Superóxido Dismutasa/metabolismo
8.
J Am Coll Cardiol ; 19(1): 205-16, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1729335

RESUMEN

Previous studies have demonstrated that intravenous administration of large doses of Fluosol, a perfluorochemical preparation, reduced infarct size 24 h after reperfusion, an effect that was associated with reduced neutrophil infiltration. The effect of a clinically tolerable dose of Fluosol on infarct size after a prolonged period of reperfusion and its mechanism of action on neutrophils remain unknown. Twenty-one anesthesized closed chest dogs were subjected to 90 min of proximal left anterior descending coronary artery occlusion and 72 h of reperfusion. An additional five dogs that did not undergo regional myocardial ischemia were utilized to explore the mechanism of action of Fluosol on neutrophil function. In the infarct study, animals were randomized to receive either intravenous Fluosol (n = 10) or an equivalent volume of Ringer's lactate solution (control; n = 11) at 15 ml/kg body weight during the last 30 min of occlusion and for the 1st 30 min of reperfusion. Fluosol significantly reduced infarct size when expressed as percent area at risk 72 h after reperfusion (13.7 +/- 2.7% vs. 38.3 +/- 4.5%, respectively, p less than 0.001). This reduction was associated with significant improvement in regional wall motion (18.4 +/- 2.3% vs. 5.5 +/- 2%, p less than 0.001). Endocardial blood flow in the ischemic bed was significantly higher 3 h after reperfusion in Fluosol-treated dogs (0.63 +/- 0.08 vs. 0.34 +/- 0.07 ml/min per g, p = 0.01). Reduced capillary plugging by neutrophils with relative preservation of endothelial cell structure was observed in Fluosol-treated animals. Infusion of Fluosol produced a marked transient decrease in peripheral neutrophil and platelet counts in both ischemic and nonischemic dogs and was associated with a significant reduction in total hemolytic complement levels. Studies of neutrophil function ex vivo revealed a reduction in chemotaxis and lysozyme degranulation after infusion of Fluosol. In vitro experiments showed that Fluosol produced a rapid and sustained activation of neutrophils determined by superoxide anion production. These data demonstrate that low dose intravenous Fluosol produces a sustained reduction in infarct size in the canine model. The beneficial effect may be in part due to the suppression of various neutrophil functions in the reperfused myocardium subsequent to peripheral activation by Fluosol. Such interventions may offer a novel therapy to enhance myocardial salvage by sequestration of circulating neutrophils during the critical early reperfusion period.


Asunto(s)
Sustitutos Sanguíneos/farmacología , Fluorocarburos/farmacología , Infarto del Miocardio/tratamiento farmacológico , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Neutrófilos/efectos de los fármacos , Animales , Sustitutos Sanguíneos/administración & dosificación , Circulación Coronaria/efectos de los fármacos , Circulación Coronaria/fisiología , Perros , Evaluación Preclínica de Medicamentos , Femenino , Fluorocarburos/administración & dosificación , Hemodinámica/efectos de los fármacos , Hemodinámica/fisiología , Masculino , Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/fisiopatología , Neutrófilos/fisiología , Factores de Tiempo
9.
Br Dent J ; 219(6): 281-5, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26404992

RESUMEN

INTRODUCTION: The first national survey of children's dental health in England and Wales was carried out in 1973. Subsequent surveys, in 1983, 1993 and 2003, included all United Kingdom health departments. The 2013 survey involved England, Wales and Northern Ireland. AIM: To consider all five surveys, from 1973 to 2013, so as to summarise trends in the dental health of children in the UK over the last 40 years. MATERIALS AND METHOD: The 2013 survey was commissioned by the Health &Social Care Information Centre and all surveys used data collected during dental examinations conducted in schools on a random sample of children by NHS dentists, together with a questionnaire to parents of those children. In 2013, a pupil questionnaire for 12- and 15-year-olds was introduced, to complement information received from parents and carers. RESULTS: A total of 69,318 children, aged 5-15 years, were involved, from 1973-2013. Caries prevalence has reduced from 72% to 41% in 5-year-olds, and from 97% to 46% in 15-year-olds in 40 years. Changes in periodontal disease, orthodontic treatment, accidental damage to anterior teeth, tooth surface loss and enamel defects, are also summarised. Behavioural and attitudinal characteristics observed in the 2013 report are listed. CONCLUSIONS: Caries is now concentrated in a minority of children. The prevalence of gingivitis has not changed a great deal in 40 years. About half of those children assessed 'in orthodontic need' receive treatment.


Asunto(s)
Enfermedades Estomatognáticas/epidemiología , Adolescente , Factores de Edad , Niño , Preescolar , Caries Dental/epidemiología , Caries Dental/historia , Inglaterra/epidemiología , Femenino , Encuestas Epidemiológicas/historia , Encuestas Epidemiológicas/estadística & datos numéricos , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Masculino , Maloclusión/epidemiología , Maloclusión/historia , Irlanda del Norte/epidemiología , Enfermedades Periodontales/epidemiología , Enfermedades Periodontales/historia , Prevalencia , Enfermedades Estomatognáticas/historia , Traumatismos de los Dientes/epidemiología , Traumatismos de los Dientes/historia , Gales/epidemiología
10.
Clin Pharmacol Ther ; 43(6): 636-42, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3378385

RESUMEN

We examined the hypothesis that excess accumulation of major quinidine metabolites or the commercial impurity dihydroquinidine contributes to the development of polymorphic ventricular tachycardia (torsades de pointes, [TdP]) in patients taking quinidine. Total and free plasma concentrations of these compounds were measured by reverse-phase HPLC with fluorescence detection and equilibrium dialysis in 19 patients with TdP and 38 control patients tolerating quinidine therapy without toxicity. No significant differences were found between the two groups of patients. Ratios of metabolite or dihydroquinidine to quinidine varied up to tenfold among patients but were similarly distributed in the TdP and control groups. Only the metabolite 3-hydroxyquinidine was present at free plasma concentrations that exceeded free concentrations of quinidine. We conclude that although quinidine metabolism is highly variable, there does not appear to be any correlation between the plasma concentrations of quinidine, its metabolites or dihydroquinidine, and the subsequent development of TdP.


Asunto(s)
Quinidina/análogos & derivados , Quinidina/metabolismo , Taquicardia/inducido químicamente , Humanos , Unión Proteica , Quinidina/efectos adversos , Quinidina/sangre , Taquicardia/metabolismo
11.
Clin Pharmacol Ther ; 69(5): 317-23, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11371999

RESUMEN

BACKGROUND: Renal allograft survival is lower in African American patients compared with white patients. Interethnic differences in cyclosporine (INN, ciclosporin) pharmacokinetics in renal transplant recipients have been described but have not been well characterized. Pharmacodynamic responses to cyclosporine have not been compared among ethnic groups. METHODS: Healthy men were studied after 5 days on a controlled diet. Cyclosporine concentrations were determined in whole blood drawn at intervals over 24 hours after administration of a microemulsion cyclosporine formulation (4 mg/kg; 9 African American subjects and 9 white subjects) and after a standard cyclosporine formulation (4 mg/kg; 10 African American subjects and 10 white subjects). Inhibition of phytohemagglutinin-P-stimulated interleukin-2 production in whole blood drawn 4 hours after cyclosporine was used as a pharmacodynamic measure to compare the effect of cyclosporine in African American and white subjects. RESULTS: The microemulsion cyclosporine formulation (area under the cyclosporine concentration-time curve, 7432 +/- 560 ng. h/mL in African American subjects and 7043 +/- 454 ng. h/mL in white subjects) was more bioavailable than the standard formulation (area under the cyclosporine concentration-time curve, 4828 +/- 319 ng. h/mL in African American subjects and 4538 +/- 301 ng. h/mL in white subjects); this resulted in an approximately 50% greater area under the cyclosporine concentration-time curve (P < .001 in both ethnic groups). There were no differences between African American subjects and white subjects in any pharmacokinetic measurement, with both the standard and the microemulsion cyclosporine formulations. Inhibition of phytohemagglutinin-P-stimulated interleukin-2 production 4 hours after the administration of cyclosporine was similar in African American subjects (70% +/- 5% inhibition) and white subjects (64% +/- 7% inhibition; P = .5). CONCLUSIONS: The pharmacokinetics and pharmacodynamics of cyclosporine were similar in a matched group of African American and white subjects studied under controlled conditions. Environmental factors may contribute more than genetic variability to the lower bioavailability of cyclosporine reported in African American renal transplant recipients.


Asunto(s)
Población Negra , Ciclosporina/farmacocinética , Inmunosupresores/farmacocinética , Población Blanca , Administración Oral , Adulto , Área Bajo la Curva , Ciclosporina/farmacología , Humanos , Inmunosupresores/farmacología , Interleucina-2/biosíntesis , Masculino
12.
Neurology ; 53(7): 1431-8, 1999 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-10534247

RESUMEN

OBJECTIVE: To determine the safety and efficacy of botulinum toxin type B (BoNT/B) in patients with type A-resistant cervical dystonia (CD). BACKGROUND: Local intramuscular injections of BoNT are an effective therapy for CD. After repeated use, some patients become resistant to therapy. BoNT/B, effective in type A toxin-responsive patients, is proposed as an alternative therapy for type A-resistant patients. METHODS: The authors performed a 16-week, double-blind, placebo-controlled trial of BoNT/B in type A-resistant patients with CD. After resistance to therapy was confirmed with the frontalis-type A test, placebo or 10,000 U BoNT/B was administered in a single session into two to four clinically involved muscles. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) was the primary efficacy measurement. TWSTRS-Total, three visual analog scales (Patient Global Assessment of Change, Principal Investigator Global Assessment of Change, Patient Analog Pain Assessment), and adverse events were assessed at baseline and weeks 2, 4, 8, 12, and 16. RESULTS: A total of 77 patients participated (38 placebo, 39 active). Improvements in severity, disability, and pain were documented in the BoNT/B-treated group. TWSTRS-Total scores were improved in the BoNT/B-treated group at weeks 4 (p = 0.0001), 8 (p = 0.0002), and 12 (p = 0.0129). All three visual analog scales demonstrated improvements at week 4 (p < 0.0001, 0.0001, and 0.001). A Kaplan-Meier analysis supported a duration of effect of 12 to 16 weeks in the active group. Dry mouth and dysphagia were self-limited adverse effects, reported more commonly in the BoNT/B group. CONCLUSIONS: Botulinum toxin type B (BoNT/B) (NeuroBloc) is safe and efficacious for the management of patients with type A-resistant cervical dystonia with an estimated duration of treatment effect of 12 to 16 weeks.


Asunto(s)
Toxinas Botulínicas/uso terapéutico , Tortícolis/tratamiento farmacológico , Adulto , Anciano , Toxinas Botulínicas/efectos adversos , Toxinas Botulínicas Tipo A/uso terapéutico , Evaluación de la Discapacidad , Método Doble Ciego , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Retratamiento , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Tortícolis/fisiopatología
13.
Neurology ; 49(3): 701-7, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9305326

RESUMEN

We enrolled and treated 122 patients with idiopathic cervical dystonia in a double-blind, placebo-controlled safety and efficacy study of botulinum toxin type B (BotB). Both A-responsive and A-resistant patients were enrolled. Patients received intramuscular injections of either BotB (2,500 U, 5,000 U, or 10,000 U) or placebo. The primary outcome measure of efficacy was the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Total score at 4 weeks following study drug administration. Secondary measures of efficacy were TWSTRS-Severity, -Disability, and -Pain subscale scores, and Analog Pain Assessment, Investigator Global Assessment, Patient Global Assessment, and Sickness Impact Profile scores. Duration of effect was estimated with an intent-to-treat analysis of responders. Safety measures included clinical parameters, laboratory tests, and adverse events. The primary and most of the secondary analyses indicated a statistically significant treatment effect and a dose response. BotB is safe, well tolerated, and efficacious in the treatment of cervical dystonia at the doses tested.


Asunto(s)
Antidiscinéticos/uso terapéutico , Toxinas Botulínicas/uso terapéutico , Distonía/tratamiento farmacológico , Músculos del Cuello/fisiopatología , Tortícolis/tratamiento farmacológico , Adulto , Anciano , Antidiscinéticos/administración & dosificación , Toxinas Botulínicas/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Distonía/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos del Cuello/efectos de los fármacos , Dimensión del Dolor , Placebos , Índice de Severidad de la Enfermedad , Perfil de Impacto de Enfermedad , Resultado del Tratamiento
14.
Neurology ; 53(7): 1439-46, 1999 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-10534248

RESUMEN

OBJECTIVE: To determine the safety and efficacy of botulinum toxin type B (BoNT/B) in patients with cervical dystonia (CD). BACKGROUND: BoNT/B is a form of chemodenervation therapy for the treatment of patients with CD. METHODS: The authors performed a 16-week, randomized, multicenter, double-blind, placebo-controlled trial of BoNT/B in patients with CD who continue to respond to botulinum toxin type A. Placebo, or 5,000 U or 10,000 U of BoNT/B was administered in two to four muscles involved clinically in CD. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Total score at week 4 was the primary efficacy measure. Clinical assessments and adverse events were recorded for treatment day 1 and at weeks 2, 4, 8, 12, and 16. RESULTS: A total of 109 patients were enrolled randomly across all three treatment groups. The mean improvement in the TWSTRS-Total scores in each group at week 4 was 4.3 (placebo), 9.3 (5,000 U), and 11.7 (10,000 U). For the prospectively defined primary contrast (10,000 U versus placebo), highly significant differences were noted for the primary (TWSTRS-Total, baseline to week 4, p = 0.0004) and supportive secondary (Patient Global Assessment, baseline to week 4, p = 0.0001) outcome measures. Improvement in pain, disability, and severity of CD occurred for patients who were treated with BoNT/B when compared with placebo-treated patients. Overall, improvements associated with BoNT/B treatment were greatest for patients who received the 10,000-U dose. The duration of treatment effect for BoNT/B was 12 to 16 weeks for both doses. CONCLUSION: Botulinum toxin type B (NeuroBloc) is safe and efficacious at 5,000 U and 10,000 U for the management of patients with cervical dystonia.


Asunto(s)
Toxinas Botulínicas/uso terapéutico , Tortícolis/tratamiento farmacológico , Adulto , Anciano , Toxinas Botulínicas/efectos adversos , Toxinas Botulínicas Tipo A/uso terapéutico , Evaluación de la Discapacidad , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Tortícolis/fisiopatología
15.
Am J Med ; 78(5): 881-4, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3993669

RESUMEN

Hypercalcemia associated with disseminated histoplasmosis in an elderly male is described. Serum calcium levels increased during vitamin D supplementation, supporting the proposed mechanism of hypercalcemia in granulomatous diseases. Rapid clinical deterioration and death occurred shortly after administration of steroids for relative adrenal insufficiency. Vitamin D and calcium supplements may aggravate the hypercalcemia of granulomatous disease and should be avoided.


Asunto(s)
Histoplasmosis/tratamiento farmacológico , Hipercalcemia/inducido químicamente , Vitamina D/efectos adversos , Calcio/efectos adversos , Calcio/sangre , Histoplasmosis/complicaciones , Histoplasmosis/fisiopatología , Humanos , Hipercalcemia/fisiopatología , Masculino , Persona de Mediana Edad
16.
Am J Med ; 75(2): 289-94, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6881181

RESUMEN

Cerebrospinal fluid levels of protein, glucose, and malignant cells may differ markedly at different levels of the neuraxis in patients with neoplastic meningitis, even in the absence of an extradural blockage to cerebrospinal fluid flow. The pathogenesis of these differences is unclear, but is probably related to focal disruption of the blood-cerebrospinal fluid barrier produced by neoplastic involvement of the meninges. The clinical implications of this new observation are important. When the diagnosis of neoplastic meningitis is strongly suspected, but malignant cells cannot be demonstrated by repeated examination of lumbar cerebrospinal fluid, samples should be obtained by cisternal tap if the neurologic deficits are manifestations from involvement of the cranial nerves or cerebrum. Similarly, response to intrathecal chemotherapy should be monitored with serial examinations of cerebrospinal fluid obtained from the site of most marked pretreatment abnormality.


Asunto(s)
Proteínas del Líquido Cefalorraquídeo/análisis , Glucosa/líquido cefalorraquídeo , Neoplasias Meníngeas/líquido cefalorraquídeo , Adulto , Anciano , Recuento de Células , Líquido Cefalorraquídeo/citología , Femenino , Humanos , Región Lumbosacra , Masculino , Persona de Mediana Edad
17.
Transplantation ; 63(4): 528-32, 1997 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-9047145

RESUMEN

Obliterative bronchiolitis (OB), an important threat to the long-term survival of lung transplant recipients, is characterized histologically by fibroproliferation within small airways. The pathogenesis of OB is thought to involve chronic allograft rejection, and therapy frequently includes augmentation of immunosuppression. We have developed a model that reproduces the pathologic lesion of OB and allows study of interventions designed to limit airway fibrosis. In this model, heterotopic transplantation of murine airways into immune-mismatched recipients results in epithelial abnormalities and fibroproliferation in the airway lumen, changes not seen in heterotopic isografts. Cyclosporine (CsA) inhibits activation and proliferation of T lymphocytes and is commonly administered after lung transplantation. We hypothesized that use of CsA in our model system would reduce fibroproliferation in tracheal allografts. To test this hypothesis, murine tracheas were transplanted heterotopically into allo matched and allomismatched recipients, and then treated with varying doses (5, 10, 15, or 25 mg/kg i.p. q.d.) of CsA. Controls included allografts and isografts not treated with CsA. After 30 days, tracheas were harvested and examined histologically. CsA markedly reduced the development of fibroproliferation in allografts (19% in treated allografts versus 90% in untreated allografts, P<0.0001), but did not reduce inflammation or airway epithelial cell injury. High-dose (25 mg/kg/day) CsA was more effective than lower doses in reducing fibroproliferation (0% in high dose versus 29% in low dose, P=0.04). These findings demonstrate that CsA significantly reduces development of the pathologic lesion of OB, and supports the role of alloimmunity in the pathogenesis of this disease.


Asunto(s)
Bronquiolitis Obliterante/prevención & control , Ciclosporina/uso terapéutico , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Tráquea/trasplante , Animales , Ciclosporina/sangre , Trasplante de Pulmón , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H
18.
Hum Pathol ; 26(5): 534-40, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7750937

RESUMEN

The bcl-2 gene is an oncogene that inhibits programmed cell death (apoptosis). We investigated by immunocytochemistry bcl-2 expression in normal colonic mucosa, hyperplastic polyps, adenomas, and adenocarcinomas of the large bowel. The purpose of the investigation was twofold; to assess the possible role of bcl-2 in colorectal tumorigenesis and to evaluate its clinical significance. The cases studied included 24 hyperplastic polyps, 49 adenomas, and 205 colorectal carcinomas. In both normal mucosa and hyperplastic polyps bcl-2 immunoreactivity was detected only in the proliferative cells of the colonic crypts. Conversely, bcl-2 immunoreactivity was noted in all adenomas irrespective of the degree of dysplastic change; it was diffuse in 84% of adenomas and focal in the remaining cases. In colorectal carcinomas bcl-2 expression was undetectable in 50% and focal (less than 50% immunostained neoplastic cells) in 38% of tumors. The remaining 12% of the carcinomas displayed diffuse (more than 50% immunostained neoplastic cells) bcl-2 immunoreactivity. In colorectal carcinomas bcl-2 expression was not correlated with relevant clinicopathologic parameters, including disease stage, tumor location and growth fraction, DNA ploidy, and p53 protein accumulation, and had no prognostic significance by univariate or multivariate analysis. These results suggest that bcl-2 oncoprotein may play a role in colorectal tumorigenesis, probably in the early phases of the adenoma-carcinoma sequence. bcl-2 expression in established tumors has no prognostic significance.


Asunto(s)
Adenocarcinoma/metabolismo , Adenoma/metabolismo , Neoplasias del Colon/metabolismo , Pólipos Intestinales/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Neoplasias del Recto/metabolismo , Adenocarcinoma/patología , Adenoma/patología , Colon/metabolismo , Neoplasias del Colon/patología , Humanos , Hiperplasia , Mucosa Intestinal/metabolismo , Pólipos Intestinales/patología , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2 , Neoplasias del Recto/patología
19.
Chest ; 120(2): 423-30, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502639

RESUMEN

STUDY OBJECTIVES: Comparison of inhaled salmeterol powder vs oral montelukast treatment in patients with persistent asthma who remained symptomatic while receiving inhaled corticosteroids. DESIGN: Randomized, double-blind, double-dummy, parallel-group, multicenter trials of 12-week duration. SETTING: Outpatients in private and university-affiliated clinics. PATIENTS: Male and female patients > or = 15 years of age with a diagnosis of asthma (baseline FEV(1) of 50 to 80% of predicted) and symptomatic despite receiving inhaled corticosteroids. INTERVENTIONS: Inhaled salmeterol xinafoate powder, 50 microg bid, or oral montelukast, 10 mg qd. MEASUREMENTS AND RESULTS: Treatment with salmeterol powder resulted in significantly greater improvements from baseline compared with montelukast for most efficacy measurements, including morning peak expiratory flow (35.0 L/min vs 21.7 L/min; p < 0.001), percentage of symptom-free days (24% vs 16%; p < 0.001), and the percentage of rescue-free days (27% vs 20%; p = 0.002). Total supplemental albuterol use was decreased significantly more in the salmeterol group compared with the montelukast group (- 1.90 puffs per day vs - 1.66 puffs per day; p = 0.004) and nighttime awakenings per week decreased significantly more with salmeterol than with montelukast (- 1.42 vs - 1.32; p = 0.015). Patients treated with inhaled salmeterol were significantly more satisfied with their treatment regimen and how well, how fast, and how long it worked than were patients who were treated with oral montelukast. The safety profiles for the two treatments were similar. CONCLUSION: In patients with persistent asthma who remain symptomatic while receiving inhaled corticosteroids, adding inhaled salmeterol powder provided significantly greater improvement in lung function and asthma symptoms and was preferred by patients over oral montelukast.


Asunto(s)
Acetatos/administración & dosificación , Corticoesteroides/administración & dosificación , Agonistas Adrenérgicos beta/administración & dosificación , Albuterol/análogos & derivados , Albuterol/administración & dosificación , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Broncodilatadores/administración & dosificación , Quinolinas/administración & dosificación , Administración por Inhalación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ciclopropanos , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polvos , Xinafoato de Salmeterol , Sulfuros
20.
Chest ; 116(3): 625-32, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10492263

RESUMEN

OBJECTIVES: To compare the efficacies of medium-dose fluticasone propionate (FP), medium-dose triamcinolone acetonide (TAA), and combined low-dose FP plus salmeterol (SL). DESIGN: Randomized, double-blind, triple-dummy, multicenter, 12-week clinical trial. SETTING: Allergy/respiratory care clinics. PATIENTS: Six hundred eighty patients with asthma previously uncontrolled with low-dose inhaled corticosteroids. INTERVENTIONS: FP, 220 microg bid; TAA, 600 microg bid; or FP, 88 microg plus SL, 42 microg bid. MEASUREMENTS AND RESULTS: Outcome measures included FEV1, peak expiratory flow (PEF), supplemental albuterol use, nighttime awakenings, asthma symptoms, and physician global assessment. Compared with TAA, 600 microg bid, treatment with FP 220, microg bid, significantly increased FEV1, morning and evening PEF, and percent symptom-free days, and significantly reduced rescue albuterol use, number of nighttime awakenings, and overall asthma symptom scores (p < or = 0.035). Improvements with low-dose FP, 88 microg, plus SL, 42 microg bid, were significantly (p < or = 0.004) greater than TAA, 600 microg bid, in all the aforementioned efficacy measures as well as percent of rescue-free days. Combined low-dose FP, 88 microg, plus SL, 42 microg bid, also significantly increased FEV1 and percent of rescue-free days, and significantly reduced albuterol use compared with medium-dose FP, 220 microg bid (p < or = 0.018). At endpoint, both FP, 220 microg bid, and FP, 88 microg, plus SL, 42 microg bid, significantly increased FEV1 by 0.48 L and 0.58 L, respectively, compared with 0.34 L with TAA, 600 microg bid. CONCLUSION: In patients who are symptomatic while taking low-dose inhaled corticosteroids, medium-dose FP (440 microg/d) and combination treatment with low-dose FP (176 microg/d) plus SL (84 microg/d) are both more effective than medium-dose TAA (1200 microg/d) in improving pulmonary function and asthma symptom control.


Asunto(s)
Agonistas Adrenérgicos beta/administración & dosificación , Albuterol/análogos & derivados , Androstadienos/administración & dosificación , Antiasmáticos/administración & dosificación , Antiinflamatorios/administración & dosificación , Asma/tratamiento farmacológico , Broncodilatadores/administración & dosificación , Triamcinolona Acetonida/administración & dosificación , Administración por Inhalación , Administración Tópica , Adolescente , Adulto , Anciano , Albuterol/administración & dosificación , Albuterol/uso terapéutico , Asma/fisiopatología , Niño , Método Doble Ciego , Quimioterapia Combinada , Femenino , Fluticasona , Volumen Espiratorio Forzado , Glucocorticoides , Humanos , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio , Xinafoato de Salmeterol , Sueño
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