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1.
Aliment Pharmacol Ther ; 32(10): 1228-39, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20955442

RESUMEN

BACKGROUND: Adalimumab induces and maintains remission in adults with Crohn's disease. AIM: To evaluate safety, fistula healing, quality of life and work productivity in adalimumab-treated patients who failed infliximab, including primary nonresponders. METHODS: After a ≥8-week infliximab washout, patients with moderate-to-severe Crohn's disease received open-label adalimumab as induction (160/80 mg at weeks 0/2) and maintenance (40 mg every other week) therapies. At/after 8 weeks, patients with flare/nonresponse could receive weekly therapy. Minimum study duration was 8 weeks, continuing until the commercial availability of adalimumab for Crohn's disease. RESULTS: Of 673 patients enrolled, 17% were infliximab primary nonresponders and 83% were initial responders. Three percent of patients had serious infections (mainly abscesses). Complete fistula healing was achieved by 34/88 (39%) patients with baseline fistulas. Improvements in quality of life and work productivity were sustained from week 4 to week 24 for all patients, as well as the subgroup of primary nonresponders. CONCLUSIONS: Blinded clinical trials have shown adalimumab to be both an effective first-line therapy for anti-TNF-naïve patients and an important treatment option for infliximab-refractory or -intolerant patients. This trial presents open-label experience to support further the safety and effectiveness of adalimumab in patients who failed infliximab therapy, including primary nonresponders (NCT00338650).


Asunto(s)
Antiinflamatorios/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Enfermedad de Crohn/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos , Absceso , Adalimumab , Adulto , Anticuerpos Monoclonales Humanizados , Eficiencia , Femenino , Fístula , Humanos , Infliximab , Masculino , Calidad de Vida , Resultado del Tratamiento , Trabajo
2.
Gut ; 58(7): 940-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19201775

RESUMEN

OBJECTIVE: To evaluate the efficacy of adalimumab in the healing of draining fistulas in patients with active Crohn's disease (CD). DESIGN: A phase III, multicentre, randomised, double-blind, placebo controlled study with an open-label extension was conducted in 92 sites. PATIENTS: A subgroup of adults with moderate to severely active CD (CD activity index 220-450) for >or=4 months who had draining fistulas at baseline. INTERVENTIONS: All patients received initial open-label adalimumab induction therapy (80 mg/40 mg at weeks 0/2). At week 4, all patients were randomly assigned to receive double-blind placebo or adalimumab 40 mg every other week or weekly to week 56 (irrespective of fistula status). Patients completing week 56 of therapy were then eligible to enroll in an open-label extension. MAIN OUTCOME MEASURES: Complete fistula healing/closure (assessed at every visit) was defined as no drainage, either spontaneous or with gentle compression. RESULTS: Of 854 patients enrolled, 117 had draining fistulas at both screening and baseline (70 randomly assigned to adalimumab and 47 to placebo). The mean number of draining fistulas per day was significantly decreased in adalimumab-treated patients compared with placebo-treated patients during the double-blind treatment period. Of all patients with healed fistulas at week 56 (both adalimumab and placebo groups), 90% (28/31) maintained healing following 1 year of open-label adalimumab therapy (observed analysis). CONCLUSIONS: In patients with active CD, adalimumab therapy was more effective than placebo for inducing fistula healing. Complete fistula healing was sustained for up to 2 years by most patients in an open-label extension trial.


Asunto(s)
Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Enfermedad de Crohn/complicaciones , Fístula Intestinal/tratamiento farmacológico , Adalimumab , Adulto , Anticuerpos Monoclonales Humanizados , Método Doble Ciego , Drenaje , Femenino , Humanos , Fístula Intestinal/etiología , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Cicatrización de Heridas
3.
Gut ; 56(9): 1232-9, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17299059

RESUMEN

BACKGROUND: Adalimumab induced clinical remission after four weeks in patients with active Crohn's disease in the CLASSIC I trial. OBJECTIVE: To evaluate long term efficacy and safety of adalimumab maintenance therapy in Crohn's disease in a follow-on randomised controlled trial (CLASSIC II). METHODS: In the preceding CLASSIC I trial, 299 patients with moderate to severe Crohn's disease naive to tumour necrosis factor antagonists received induction therapy with adalimumab 40 mg/20 mg, 80 mg/40 mg, or 160 mg/80 mg, or placebo, at weeks 0 and 2. In all, 276 patients from CLASSIC I enrolled in CLASSIC II and received open-label adalimumab 40 mg at weeks 0 (week 4 of CLASSIC I) and 2; 55 patients in remission at both weeks 0 and 4 were re-randomised to adalimumab 40 mg every other week, 40 mg weekly, or placebo for 56 weeks. Patients not in remission at both weeks 0 and 4 were enrolled in an open-label arm and received adalimumab 40 mg every other week. With non-response or flare, these patients could have their dosages increased to 40 mg weekly. Patients in the randomised arm with continued non-response or disease flare could switch to open-label adalimumab 40 mg every other week and again to 40 mg weekly. The primary end point was maintenance of remission (CDAI <150) in randomised patients through week 56. RESULTS: Of 55 patients randomised at week 4, 79% who received adalimumab 40 mg every other week and 83% who received 40 mg weekly were in remission at week 56, v 44% for placebo (p<0.05). In all, 204 patients entered the open-label arm. Of these, 93 (46%) were in clinical remission at week 56. Adalimumab was generally well-tolerated in all patients. CONCLUSIONS: Adalimumab induced and maintained clinical remission for up to 56 weeks in patients with moderate to severe Crohn's disease naive to anti-TNF treatment.


Asunto(s)
Antiinflamatorios/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Enfermedad de Crohn/tratamiento farmacológico , Adalimumab , Adulto , Antiinflamatorios/efectos adversos , Antiinflamatorios/sangre , Anticuerpos/sangre , Anticuerpos Antinucleares/sangre , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/sangre , Anticuerpos Monoclonales Humanizados , Enfermedad de Crohn/sangre , Enfermedad de Crohn/inmunología , Método Doble Ciego , Esquema de Medicación , Quimioterapia Combinada , Femenino , Humanos , Inmunosupresores/uso terapéutico , Inyecciones Subcutáneas , Cuidados a Largo Plazo/métodos , Masculino , Resultado del Tratamiento
4.
Ann Rheum Dis ; 65(7): 889-94, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16439435

RESUMEN

OBJECTIVE: To assess the safety of adalimumab in global clinical trials and postmarketing surveillance among patients with rheumatoid arthritis (RA). METHODS: Safety data for adalimumab treated patients from randomised controlled trials, open label extensions, and two phase IIIb open label trials were analysed. In addition, postmarketing spontaneous reports of adverse events in the United States were collected following Food and Drug Administration approval of adalimumab on 31 December 2002. RESULTS: As of 15 April 2005, the RA clinical trial safety database analysed covered 10,050 patients, representing 12,506 patient-years (PYs) of adalimumab exposure. The rate of serious infections, 5.1/100 PYs, was comparable to that reported on 31 August 2002 (4.9/100 PYs), and to published reports of RA populations naive to anti-tumour necrosis factor (TNF) therapy. Following implementation of tuberculosis (TB) screening in clinical trials, the rate of TB decreased. There were 34 cases of TB as of this analysis (0.27/100 PYs). The standardised incidence ratio for lymphoma was 3.19 (95% CI 1.78 to 5.26), consistent with the observed increased incidence in the general RA population. As of 30 June 2005, there were an estimated 78 522 PYs of exposure to adalimumab in the US postmarketing period. Seventeen TB cases were spontaneously reported (0.02/100 PYs) from the US. Rates of other postmarketing events of interest, such as congestive heart failure, systemic lupus erythematosus, opportunistic infections, blood dyscrasias, lymphomas, and demyelinating disease, support observations from clinical trials. CONCLUSION: Analyses of these data demonstrate that long term adalimumab treatment is generally safe and well tolerated in patients with RA.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Factores Inmunológicos/uso terapéutico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Artritis Reumatoide/complicaciones , Infecciones Bacterianas/complicaciones , Bases de Datos Factuales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Linfoma/complicaciones , Prevalencia , Vigilancia de Productos Comercializados , Ensayos Clínicos Controlados Aleatorios como Asunto , Prueba de Tuberculina
5.
Aliment Pharmacol Ther ; 20(5): 527-38, 2004 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15339324

RESUMEN

AIM: In a predefined analysis, data were pooled from eight blinded, randomized, controlled trials, and separately from three long-term, open-label trials to determine the rate of upper gastrointestinal ulcer complications with the cyclo-oxygenase-2 selective inhibitor, valdecoxib, vs. non-selective non-steroidal anti-inflammatory drugs. METHODS: In randomized, controlled trials, 7434 osteoarthritis and rheumatoid arthritis patients received placebo (n = 973), valdecoxib 5-80 mg daily (n = 4362), or a non-selective non-steroidal anti-inflammatory drug (naproxen, ibuprofen or diclofenac; n = 2099) for 12-26 weeks. In long-term, open-label trials, 2871 patients received valdecoxib 10-80 mg daily for up to 1 year. All potential events were reviewed by a blinded, independent review committee based on a priori definitions of ulcer complications (perforations, obstructions, bleeds). RESULTS: In randomized, controlled trials, 19 of 955 potential events were adjudicated to be ulcer complications. Valdecoxib was associated with a significantly lower ulcer complication rate than non-selective non-steroidal anti-inflammatory drugs (0.68% vs. 1.96%, all patients; 0.29% vs. 2.08%, non-aspirin users; P < 0.05). In long-term, open-label trials, seven of 310 potential events were adjudicated to be ulcer complications; the annualized incidence for valdecoxib was 0.39% (seven of 1791 patient-years) for all patients and 0.2% (three of 1472 patient-years) for non-aspirin users. CONCLUSIONS: Valdecoxib, including above recommended doses, is associated with a significantly lower rate of upper gastrointestinal ulcer complications than therapeutic doses of non-selective non-steroidal anti-inflammatory drugs.


Asunto(s)
Inhibidores de la Ciclooxigenasa/efectos adversos , Isoenzimas/antagonistas & inhibidores , Isoxazoles/efectos adversos , Úlcera Péptica/inducido químicamente , Sulfonamidas/efectos adversos , Adulto , Anciano , Antiinflamatorios no Esteroideos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Femenino , Humanos , Masculino , Proteínas de la Membrana , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Osteoartritis/tratamiento farmacológico , Prostaglandina-Endoperóxido Sintasas , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
Aliment Pharmacol Ther ; 18(1): 125-32, 2003 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12848634

RESUMEN

BACKGROUND: In long-term outcomes studies, cyclooxygenase COX-2 specific inhibitors spare COX-1 at supratherapeutic doses and therefore demonstrate improved gastrointestinal safety over nonspecific nonsteroidal anti-inflammatory drugs (NSAIDs). However, in clinical practice, anti-inflammatory drugs are often used for short-term treatment of pain. AIM: To compare the short-term upper gastrointestinal mucosal effects of naproxen with the new COX-2 specific inhibitor, valdecoxib, or placebo, in elderly subjects. METHODS: In this multicentre, double-blind, randomized, study, elderly subjects (65-76 years old), with a normal baseline esophagogastroduodenoscopy (EGD), received oral valdecoxib (a supratherapeutic 40 mg b.d. dosage, n = 62), naproxen (500 mg b.d., n = 62), or placebo (n = 62) for 6.5 days. Upper gastrointestinal mucosal injury was evaluated post-treatment by EGD (day 7). RESULTS: Subjects receiving naproxen (11/60, 18%) had significantly more gastroduodenal ulcers post-treatment than those receiving placebo (2/61, 3%; P < 0.01) or valdecoxib (0/60, 0%; P < 0.001). A similar significant finding was observed for gastric ulcer rates. All treatments had similar adverse event rates and clinical laboratory findings. CONCLUSIONS: Valdecoxib, even at supratherapeutic doses, was associated with an ulcer rate significantly lower than naproxen but similar to placebo in healthy elderly subjects, despite the short duration of therapy (6.5 days). Naproxen and valdecoxib were as well tolerated as placebo.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Inhibidores de la Ciclooxigenasa/efectos adversos , Enfermedades Gastrointestinales/inducido químicamente , Isoxazoles/efectos adversos , Naproxeno/efectos adversos , Sulfonamidas/efectos adversos , Administración Oral , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Inhibidores de la Ciclooxigenasa/administración & dosificación , Humanos , Mucosa Intestinal/efectos de los fármacos , Isoxazoles/administración & dosificación , Naproxeno/administración & dosificación , Osteoartritis/tratamiento farmacológico , Dolor/tratamiento farmacológico , Factores de Riesgo , Sulfonamidas/administración & dosificación
7.
JAMA ; 284(10): 1247-55, 2000 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-10979111

RESUMEN

CONTEXT: Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a spectrum of toxic effects, notably gastrointestinal (GI) effects, because of inhibition of cyclooxygenase (COX)-1. Whether COX-2-specific inhibitors are associated with fewer clinical GI toxic effects is unknown. OBJECTIVE: To determine whether celecoxib, a COX-2-specific inhibitor, is associated with a lower incidence of significant upper GI toxic effects and other adverse effects compared with conventional NSAIDs. DESIGN: The Celecoxib Long-term Arthritis Safety Study (CLASS), a double-blind, randomized controlled trial conducted from September 1998 to March 2000. SETTING: Three hundred eighty-six clinical sites in the United States and Canada. PARTICIPANTS: A total of 8059 patients (>/=18 years old) with osteoarthritis (OA) or rheumatoid arthritis (RA) were enrolled in the study, and 7968 received at least 1 dose of study drug. A total of 4573 patients (57%) received treatment for 6 months. INTERVENTIONS: Patients were randomly assigned to receive celecoxib, 400 mg twice per day (2 and 4 times the maximum RA and OA dosages, respectively; n = 3987); ibuprofen, 800 mg 3 times per day (n = 1985); or diclofenac, 75 mg twice per day (n = 1996). Aspirin use for cardiovascular prophylaxis (

Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Inhibidores de la Ciclooxigenasa/efectos adversos , Enfermedades Gastrointestinales/inducido químicamente , Isoenzimas/antagonistas & inhibidores , Isoenzimas/farmacología , Prostaglandina-Endoperóxido Sintasas/farmacología , Sulfonamidas/efectos adversos , Anciano , Análisis de Varianza , Artritis Reumatoide/tratamiento farmacológico , Aspirina/efectos adversos , Celecoxib , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Diclofenaco/efectos adversos , Método Doble Ciego , Femenino , Humanos , Ibuprofeno/efectos adversos , Masculino , Proteínas de la Membrana , Persona de Mediana Edad , Osteoartritis/tratamiento farmacológico , Úlcera Péptica/inducido químicamente , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Pirazoles
8.
Cardiovasc Res ; 42(1): 206-13, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10435012

RESUMEN

OBJECTIVE: Both disruption of the endothelial nitric oxide synthase (eNOS) gene and pharmacological inhibition of the NOS produce modest hypertension. It is unclear if and to what extent NOS isoforms other than eNOS contribute to this effect and how loss of one copy of the eNOS gene might impact on vascular reactivity or eNOS protein expression. METHODS: We examined protein expression, vascular reactivity, activity of soluble guanylate cyclase, blood pressure and heart rate in mice completely lacking the eNOS gene (eNOS-/-), wild-type mice (eNOS+/+) and mice heterozygotic for the eNOS gene (eNOS+/-). RESULTS: While eNOS-/- mice had mild hypertension and bradycardia, eNOS+/- mice were normotensive. In control mice, oral administration of L-NAME (approximately 100 mg/kg/day x 21 days) increased blood pressure to levels observed in eNOS-/- mice. In eNOS-/- mice, chronic oral administration of L-NAME had no effect on blood pressure, suggesting that inhibition of other NOS isoforms unlikely contribute to hypertension. L-NAME treatment induced bradycardia in both control and eNOS-/- mice, suggesting that both eNOS and other isoforms of NOS might be involved in heart rate control. Studies of aortic rings from eNOS-/- mice revealed a complete lack of endothelium-dependent vascular relaxation in response to acetylcholine and the calcium ionophore A23187 and an increase in sensitivity to phenylephrine, serotonin and nitroglycerin. Aortic rings from eNOS+/- mice demonstrated only minor alterations of responses to nitroglycerin and a normal relaxation to either acetylcholine or A23187 compared to vessels from eNOS-/+. Western analysis demonstrated that eNOS expression was virtually identical between eNOS+/+ and eNOS+/- mice and was absent in eNOS-/- mice. The activity of lung-isolated soluble guanylate cyclase was identical in the three strains of mice. CONCLUSIONS: We conclude that loss of one copy of the eNOS gene, as observed in heterozygotic animals, has no effect on vascular reactivity, blood pressure or eNOS protein expression. Isoforms of NOS, other than eNOS are unlikely involved in blood pressure regulation but may participate in heart rate control.


Asunto(s)
Hemodinámica/genética , Hipertensión/genética , Isoenzimas/metabolismo , Óxido Nítrico Sintasa/metabolismo , Animales , Aorta Torácica , Presión Sanguínea/genética , Western Blotting , Inhibidores Enzimáticos/farmacología , Eliminación de Gen , Expresión Génica , Guanilato Ciclasa/metabolismo , Frecuencia Cardíaca/genética , Heterocigoto , Hipertensión/metabolismo , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/análisis , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Vasoconstricción/genética
9.
J Mol Cell Cardiol ; 30(6): 1215-23, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9689595

RESUMEN

The inducible nitric oxide (NO) synthase (iNOS or NOS2) generates a prolonged release of large amounts of NO which may be cytotoxic and/or inhibit myocyte contractility. It has been suggested that this mechanism specifically contributes to heart failure caused by dilated cardiomyopathy (DCM). To test this hypothesis we compared the myocardial amount and localization of iNOS in myocardial biopsies from patients with heart failure caused by either DCM or ischemic heart disease (IHD). During heart transplantation, myocardial biopsies collected from the diseased heart after explantation were frozen in liquid nitrogen. Twenty-two patients in NYHA class III-IV were included (DCM: n = 8; IHD: n = 14). In each biopsy, iNOS expression was assessed using reverse transcription polymerase chain reaction (RT-PCR), and visualized by immunohistochemistry. iNOS was detected in all biopsies. Intriguingly, the amount of iNOS mRNA (shown as iNOS cDNA normalized to GADPH cDNA) did not differ significantly between the two groups (DCM 30 +/- 7; IHD 20 +/- 6, mean +/- S.E.M., P > 0.05). Similarly, no inter-group differences in the amount of iNOS protein (Western) were observed. iNOS was invariably located to vascular endothelial and smooth muscle cells. In addition, an iNOS reaction in relation to the myocyte membrane was found in 4 of the 22 patients. These four patients (two from each group) had significantly (P < 0.05) higher iNOS/GADPH ratios (54 +/- 20) than patients without myocyte membrane iNOS reaction (17 +/- 15). In conclusion, iNOS is expressed in the myocardium of all patients with heart failure caused by either DCM or IHD. iNOS is located primarily and invariably in the endothelium and vascular smooth muscle cells of the myocardial vasculature and its expression appears to be associated with the condition of heart failure per se rather than related to the heart failure etiology.


Asunto(s)
Cardiomiopatía Dilatada/enzimología , Insuficiencia Cardíaca/enzimología , Isquemia Miocárdica/enzimología , Miocardio/enzimología , Óxido Nítrico Sintasa/metabolismo , Adulto , Western Blotting , Femenino , Humanos , Inmunohistoquímica/métodos , Masculino , Persona de Mediana Edad , Óxido Nítrico Sintasa/análisis , Reacción en Cadena de la Polimerasa
10.
J Immunol ; 157(10): 4641-7, 1996 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8906844

RESUMEN

The intracellular mechanisms that regulate the function of human neutrophils are not well understood. Receptor-initiated signaling events result in the production of several second messengers (e.g., Ca2+, diacylglycerol, phosphatidic acid, and arachidonic acid) with the potential to activate members of the protein kinase C (PKC) family of signaling enzymes. The mixture of second messenger signaling molecules produced usually varies, depending on the particular receptor engaged. Previous work suggests that PKC has complex regulatory effects on neutrophil function. This may be due to the presence of multiple isoforms of the enzyme family, responding differentially to the second messengers produced. In studies to identify the PKC isoforms present in human neutrophils, we discovered the presence of the PKC isoform delta in these cells. Like other previously identified isoforms (alpha, beta I, beta II, and zeta), delta is a cytosolic enzyme in unstimulated neutrophils and partially translocates to membrane-containing fractions in cells stimulated by either the PKC activator PMA or the chemoattractant FMLP. Partial purification of cytosolic PKC gave two peaks of activity. The beta isoforms predominated in peak I, while the delta isoform predominated in peak II. The identification of delta indicates that neutrophils contain at least one member of the Ca(2+)-independent, diacylglycerol-dependent subfamily of PKC isoforms. Thus, this isoform may participate in Ca(2+)-independent, but diacylglycerol-dependent signaling events in these cells.


Asunto(s)
Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Neutrófilos/enzimología , Proteína Quinasa C/aislamiento & purificación , Proteína Quinasa C/metabolismo , Transporte Biológico , Calcio/fisiología , Diglicéridos/fisiología , Humanos , Isoenzimas/sangre , Proteína Quinasa C/sangre , Proteína Quinasa C-delta , Transducción de Señal/fisiología
11.
J Biol Chem ; 271(11): 6435-40, 1996 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8626444

RESUMEN

The calmodulin (CaM)-binding regions in bovine endothelial nitric oxide synthase (eNOS) and murine inducible nitric oxide synthase (iNOS) are identified in this study as eNOS residues 493-512 and iNOS residues 501-532. Peptides corresponding to eNOS 493-512 and NOS 501-532 produce a (Ca2+)-dependent, electrophoretic mobility shift of CaM on 4 M urea gels. The two peptides are also potent inhibitors of the CaM-mediated activation of neuronal nitric oxide synthase and have dissociation constants for CaM binding of 4.0 and 1.5 nM respectively. Substitution of eNOS and iNOS CaM-binding domains in eNOS/iNOS chimeric proteins produces major alterations in the Ca2+ and CaM dependence of the intact enzymes expressed and purified from a baculovirus/Sf9 insect cell system. Replacement of aligned NOS sequence with eNOS 493-512 creates a functional, chimeric iNOS that is both (Ca2+)- and CaM-dependent. Replacement of aligned eNOS sequence with NOS 501-532 creates a functional, chimeric eNOS that is CaM-independent but that remains (Ca2+)-dependent. Specific amino acid residues critical for CaM binding by eNOS are also identified in this study as Phe-498, Lys-499, and Leu-511 in the bovine eNOS sequence.


Asunto(s)
Calmodulina/metabolismo , Óxido Nítrico Sintasa/metabolismo , Secuencia de Aminoácidos , Animales , Baculoviridae/genética , Sitios de Unión/genética , Calcio/metabolismo , Bovinos , Línea Celular , Pollos , Endotelio/enzimología , Inducción Enzimática , Ratones , Datos de Secuencia Molecular , Óxido Nítrico Sintasa/química , Óxido Nítrico Sintasa/genética , Conejos , Ratas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Homología de Secuencia de Aminoácido , Spodoptera
12.
Pediatrics ; 96(2 Pt 1): 320-5, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7630692

RESUMEN

OBJECTIVE: This study evaluated the effects on behavior and sleep of methylphenidate (MPH) administered at 4 PM to children with attention-deficit hyperactivity disorder (ADHD). METHODOLOGY: Twelve children admitted to a child psychiatric inpatient service with ADHD participated in a double-blind, crossover study in which they received a 4 PM dose of either 15 mg of MPH, 10 mg of MPH, or a placebo in random order for 12 consecutive days. Ratings of behavior, including ADHD symptoms, pertaining to the period from dose administration until sleep onset, were supplied nightly by hospital staff. Sleep latency and sleep adequacy were also assessed for each night. RESULTS: MPH resulted in markedly improved behavioral control compared with placebo; there was no difference between 15-mg and 10-mg MPH doses. MPH did not alter sleep latencies observed with the placebo. Children were more often rated as less tired on awakening after nights that they received 10 mg of MPH compared with 15 mg of MPH and the placebo. Weight loss was apparent among 83% of the patients, but dinner intake did not vary with third-dose condition. CONCLUSIONS: Morning and noon administration of stimulants to children with ADHD is a near-universal practice, but many clinicians avoid a third, late-afternoon administration for fear of inducing insomnia. This study's findings show that children with ADHD derive substantial symptom reduction from MPH administered in late afternoon, with no untoward effects on sleep. Therefore, three-times-a-day dosing should be considered for those children exhibiting ADHD symptoms in the evening. Adverse effects on sleep latency were not apparent in the sample overall. Nonetheless, monitoring for possible aggravation of sleep problems and weight loss remains sound treatment practice.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Conducta Infantil/efectos de los fármacos , Metilfenidato/uso terapéutico , Sueño/efectos de los fármacos , Trastorno por Déficit de Atención con Hiperactividad/psicología , Niño , Preescolar , Estudios Cruzados , Método Doble Ciego , Esquema de Medicación , Ingestión de Alimentos , Fatiga/prevención & control , Femenino , Humanos , Masculino , Metilfenidato/administración & dosificación , Placebos , Fases del Sueño/efectos de los fármacos , Vigilia/efectos de los fármacos , Pérdida de Peso
13.
J Subst Abuse Treat ; 11(3): 247-51, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8072053

RESUMEN

The syndrome of factitious disorders with physical symptoms was named "Munchausen's syndrome" by Richard Asher (1951). The present article contains an interesting case report of a patient who has a history of Munchausen's syndrome, substance abuse, and genuine physical illness. A review of the literature supports a strong association of substance abuse in patients with Munchausen's syndrome. Also important for clinicians to remember is that patients with Munchausen's syndrome often have true physical illnesses which need appropriate treatment. The patient described here has successfully begun treatment with methadone maintenance, but further study will be needed regarding methadone maintenance's role in the management of Munchausen's syndrome.


Asunto(s)
Síndrome de Munchausen/psicología , Trastornos Relacionados con Sustancias/psicología , Adulto , Femenino , Estado de Salud , Humanos , Metadona/uso terapéutico , Síndrome de Munchausen/complicaciones , Embarazo , Violación , Maltrato Conyugal , Trastornos Relacionados con Sustancias/complicaciones
14.
J Biol Chem ; 267(28): 20481-8, 1992 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-1328200

RESUMEN

Propranolol, a beta-adrenergic receptor antagonist, also inhibits phosphatidate phosphohydrolase, the enzyme that converts phosphatidic acid into diacylglycerol. This latter effect has prompted recent use of propranolol in studies examining the importance of diacylglycerol and phosphatidic acid in cellular signalling events. Here, we show that propranolol is also an inhibitor of protein kinase C. At concentrations greater than or equal to 20 microM, propranolol reduced [3H]phorbol dibutyrate binding (IC50 = 200 microM) and phorbol myristate acetate-stimulated superoxide anion release (IC50 = 130 microM) in human neutrophils. Scatchard analysis showed that propranolol lowers the number of phorbol diester binding sites without significantly affecting their affinity. In vitro kinetic analysis, performed in a mixed micellar assay with protein kinase C purified from human neutrophils, suggested a competitive inhibition of propranolol with the cofactor phosphatidylserine. Complex kinetic patterns were observed with respect to diacylglycerol and ATP, approximating competitive and noncompetitive inhibition, respectively. Taken together, these results suggest that the drug interacts at the level of the regulatory domain of the enzyme. Fifty % inhibition occurred at approximately 150 microM propranolol. Similar levels of inhibition were obtained using exogenous (histone) and endogenous (p47-phox, a NADPH oxidase component) substrates. Protein kinase C-alpha and protein kinase C-beta, two protein kinase C isozymes present in human neutrophils, were inhibited by propranolol in a comparable manner. In the range of concentrations tested (30-1000 microM), neither cAMP-dependent protein kinase nor neutrophil protein tyrosine kinases were affected. The racemic form of propranolol and the (+) and the (-) stereoisomers were equally active, and other beta-adrenergic receptor antagonists (pindolol) and agonists (isoproterenol) were inactive. This suggests that the inhibitory action of propranolol on protein kinase C is related to the amphipathic nature of the drug rather than to its beta-adrenergic receptor blocking ability. Analogs of propranolol were synthesized and found to be more potent protein kinase C inhibitors, with IC50 values in the 10-20 microM range. We conclude that the ability of propranolol to inhibit both protein kinase C and PA phosphohydrolase complicates interpretation of results when this drug is used in signal transduction studies. In addition, propranolol may be a useful prototype for the synthesis of new protein kinase C inhibitors.


Asunto(s)
Fosfatidato Fosfatasa/antagonistas & inhibidores , Propranolol/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Células Cultivadas , Diglicéridos/farmacología , Electroforesis en Gel de Poliacrilamida , Humanos , Isoenzimas/antagonistas & inhibidores , Neutrófilos/enzimología , Neutrófilos/metabolismo , Forbol 12,13-Dibutirato/metabolismo , Fosfatidilserinas/farmacología , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Superóxidos/metabolismo
15.
Am J Physiol ; 260(3 Pt 1): C409-16, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1706142

RESUMEN

We have assessed the time course of alterations in several biochemical parameters and expression of specific mRNAs in gastrocnemius muscle following both the induction of diabetes and the administration of insulin to diabetic rats. Muscle mass, total RNA, and total protein were reduced, whereas poly(A)+ RNA relative to total RNA was increased following the induction of diabetes. All the above parameters, with the exception of poly(A)+ RNA, were reciprocally and rapidly altered following administration of insulin to 3-day diabetic animals. These changes suggest that during the induction of diabetes 1) total cellular protein is reduced at a rate that is less than the reduction in gastrocnemius mass, whereas RNA is reduced at a rate 1.5 times the reduction in tissue mass, and 2) poly(A)+ RNA is elevated relative to total RNA. After insulin administration, there appears to be coordinate synthesis of both poly(A)+ RNA and ribosomal RNA, assuming 85% of total RNA is ribosomal. Therefore, we conclude that poly(A)+ RNA is more stable than ribosomal RNA during diabetes, whereas the amounts of poly(A)+ RNA and ribosomal RNA are increased at the same rates following insulin administration to diabetic animals. Analysis of expression of specific gene products over the same time course, as assessed by in vitro translation of total RNA followed by two-dimensional gel analysis, suggests that there are a few mRNAs that are very rapidly altered in response to insulin administration. The mRNAs that are altered demonstrate variable temporal patterns of either repression or full or transient expression. These rapid, but limited, alterations in gene expression may prove important in the development of the defects that occur in skeletal muscle in response to diabetes.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Insulina/uso terapéutico , Músculos/metabolismo , Poli A/metabolismo , ARN Mensajero/metabolismo , ARN/metabolismo , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Cinética , Masculino , Músculos/efectos de los fármacos , ARN/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Ratas , Ratas Endogámicas , Valores de Referencia , Factores de Tiempo , Transcripción Genética/efectos de los fármacos
16.
J Neurosci Methods ; 35(1): 63-73, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1980518

RESUMEN

The power of immunohistochemical staining as a tool for the study of the neurochemical anatomy of the brain would be greatly enhanced if quantitative measures of staining were to be developed. We have here assessed the reliability and validity of two population measures of extent of fiber innervation: percent area occupied by staining, and average optical density (AOD) of staining. We have evaluated these measures for tyrosine hydroxylase-positive staining of the striatum in relation to apomorphine-induced rotational behavior in 6-hydroxydopamine lesioned rats. We have found that inter-operator reliability for the area measure is high (r = 0.98). Apomorphine-induced rotations were observed when the area measured was reduced to 2% or less of the control side, and when the density measure was reduced to 15% or less. These results are similar to those obtained previously for biochemical assay of TH activity, which showed rotations at reductions to 10% or less. We conclude that these density measures provide valid relative indices of extent of fiber innervation on the same section. The AOD measure appears to be more sensitive at lower levels of innervation.


Asunto(s)
Apomorfina/farmacología , Cuerpo Estriado/fisiología , Hidroxidopaminas/toxicidad , Fibras Nerviosas/fisiología , Conducta Estereotipada/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo , Animales , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/enzimología , Densitometría/métodos , Técnicas para Inmunoenzimas , Masculino , Fibras Nerviosas/efectos de los fármacos , Fibras Nerviosas/enzimología , Neurotoxinas/toxicidad , Oxidopamina , Ratas , Ratas Endogámicas , Valores de Referencia
17.
Am J Physiol ; 254(5 Pt 1): C634-42, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3364551

RESUMEN

A nephrotic syndrome was experimentally induced in rats by a single intravenous injection of aminonucleoside of puromycin. Experimental animals were studied 8 days after the injection, at which time they exhibited marked proteinuria and hypoalbuminemia compared with control animals. The experimental animals also exhibited alterations in protein synthesis in liver as evidenced by a marked increase in the rate of albumin synthesis relative to total hepatic protein synthesis, changes in the relative concentrations of several plasma proteins, an increased protein content of plasma, an increased liver weight relative to body weight, and an increased RNA content of liver. Perfused liver preparations derived from nephrotic rats exhibited an increased release of albumin and other secretory proteins compared with control preparations. In contrast, there was no difference in the rate of synthesis of nonexported proteins between the two groups. The elevation in the relative rate of albumin synthesis was accompanied by a relative increase of the same magnitude in albumin mRNA. Furthermore, the relative amounts of several other mRNAs, including those coding for beta-fibrinogen, haptoglobin, metallothionein II, and two unidentified proteins, were increased, whereas the amount of mRNA coding for alpha 1-acid glycoprotein was decreased in livers of nephrotic rats compared to controls. These results indicate that nephrosis leads to marked alterations in the synthesis of albumin and other plasma proteins. Mechanisms responsible for these alterations include changes in the relative abundance of specific mRNAs and an increase in total cellular RNA.


Asunto(s)
Hígado/metabolismo , Nefrosis/fisiopatología , Biosíntesis de Proteínas , Animales , Inmunoelectroforesis Bidimensional , Masculino , Metionina/metabolismo , Nefrosis/inducido químicamente , Perfusión , Proteínas/genética , Puromicina Aminonucleósido , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas
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