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1.
Mult Scler ; 12(3): 309-20, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16764344

RESUMEN

A decade of continuous glatiramer acetate (GA) use by relapsing remitting multiple sclerosis (RRMS) patients was evaluated in this ongoing, prospective study, and the neurological status of 'Withdrawn' patients was assessed at a 10-year long-term follow-up (LTFU) visit. Modified intention-to-treat (mITT, n=232) patients received > or =1 GA dose since 1991; 'Ongoing' patients (n = 108) continued in November 2003. Of 124 patients, 50 Withdrawn patients returned for LTFU. Patients were evaluated every six months (EDSS). Mean GA exposure was 6.99, 10.1 and 4.26 years for mITT, Ongoing, and Withdrawn/LTFU patients, respectively. While on GA, mITT relapse rates declined from 1.18/year prestudy to approximately 1 relapse/5 years; median time to > or = 1 EDSS point increase was 8.8 years; mean EDSS change was 0.73 +/- 1.66 points; 58% had stable/improved EDSS scores; and 24, 11 and 3% reached EDSS 4, 6 and 8, respectively. For Ongoing patients, EDSS increased 0.50 +/- 1.65; 62% were stable/improved; and 24,8 and 1% reached EDSS 4, 6 and 8, respectively. For Withdrawn patients at 10-year LTFU, EDSS increased 2.24 +/- 1.86; 28% were stable/improved; and 68, 50 and 10% reached EDSS 4, 6 and 8, respectively. While on GA nearly all patients (mean disease duration 15 years) remained ambulatory. At LTFU, Withdrawn patients had greater disability than Ongoing patients.


Asunto(s)
Inmunosupresores/administración & dosificación , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Péptidos/administración & dosificación , Adulto , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Acetato de Glatiramer , Humanos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/efectos adversos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Pacientes Desistentes del Tratamiento , Péptidos/efectos adversos , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
2.
Acta Neurol Scand ; 111(1): 42-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15595937

RESUMEN

OBJECTIVE: To assess the long-term effectiveness of continuous glatiramer acetate (GA) therapy in relapsing-remitting multiple sclerosis (RRMS). METHODS: This open-label extension followed a randomized, placebo-controlled, double-blind study of GA of approximately 30 months duration. Patients originally randomized to GA continued on it (group A) and those randomized to placebo switched to GA (group B). RESULTS: Of 251 original patients, 142 (56.6%) remained in the study after 8 years. Annual relapse rate for both groups declined to approximately 0.2 (approximately one relapse every 5 years). However, a significantly larger proportion of patients in group A had stable or improved Expanded Disability Status Scale scores compared with group B (65.3% vs 50.4%, respectively; P = 0.0263), possibly attributable to the delay of GA treatment for approximately 30 months in group B. GA was well tolerated and no drug-related laboratory changes were observed. CONCLUSIONS: These data support early initiation of GA therapy as an efficacious and well-tolerated long-term treatment for RRMS patients.


Asunto(s)
Inmunosupresores/administración & dosificación , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Péptidos/administración & dosificación , Evaluación de la Discapacidad , Acetato de Glatiramer , Humanos , Inmunosupresores/efectos adversos , Péptidos/efectos adversos , Estudios Prospectivos , Recurrencia , Factores de Tiempo , Resultado del Tratamiento
3.
Mult Scler ; 9(6): 585-91, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14664471

RESUMEN

The aim of this study was to assess the long-term safety and efficacy of glatiramer acetate (GA) for patients with multiple sclerosis (MS) who received active treatment versus those on placebo for approximately 30 months (24-35 months) before receiving GA during a six-year organized, prospective open label study. Entry required two relapses in the previous two years and an Expanded Disability Status Scale (EDSS) score of 0-5. Patients (251) were equally randomized to daily subcutaneous GA, 20 mg, or to placebo. After approximately 30 months, 208 patients continued in an open label study: 101 continued on GA and 107 switched from placebo to active drug. Groups were well matched at randomization and entry to the open label study. Patients always on GA showed a steady decline in relapses: a mean of 1.5 per year at entry, a mean of 0.42 over the entire six years (95% CI = 0.34-0.51), a 72% reduction (P = 0.0001). They averaged a relapse every four + years (yearly rate 0.23 in year six) and 26/101 remain relapse free. Patients did less well if on placebo for 30 months, but relapses then declined, and by year six the rates were similar. Of patients always on GA, 69% showed neurological improvement of > or = 1 EDSS steps or remained stable compared with 57% if GA treatment was delayed. Of relapse-free patients always on GA over six years, only three of 26 (11%) were worse by > or = 1 EDSS steps, whereas nine of 21 (43%) in the placebo/active group were worse (P < 0.03). Disability, measured every six months, showed that the group of patients always on GA was relatively stable over the six years, while the group who received placebo for the first two-and-a-half years did significantly less well. Daily injections of GA were well tolerated. This longest ever organized MS treatment trial shows that delaying therapy with GA increases the risk of neurologic disability, reinforcing the rationale for using GA as a first-line treatment early in the course of relapsing-remitting MS.


Asunto(s)
Inmunosupresores/administración & dosificación , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Péptidos/administración & dosificación , Evaluación de la Discapacidad , Acetato de Glatiramer , Humanos , Inmunosupresores/efectos adversos , Imagen por Resonancia Magnética , Esclerosis Múltiple Recurrente-Remitente/patología , Péptidos/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento
4.
Am J Health Syst Pharm ; 58(12): 1126-32, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11449856

RESUMEN

The frequency, preventability, severity, root causes, and projected costs of adverse drug events (ADEs) occurring after or causing admission to a four-hospital integrated academic health network were studied. The sample included all admissions during a 53-day study period. Events were identified through daily record review of a random patient sample, computerized flags, and self-reporting. A case review committee validated the occurrence, classification, and root causes of the events. Additional length of stay and costs associated with ADEs were analyzed by using a case-control, multiple linear regression model. The estimated ADE rate during hospitalization was 4.2 events per 100 admissions, with a cost of $2162 per ADE. In addition, 3.2% of admissions were caused by ADEs, with an associated cost of $6685 per event. Fifteen percent of hospital ADEs and 76% of ADEs causing admission were judged preventable. The annual cost to the organization for events occurring during hospitalization was $1.7 million, and the cost of preventable ADEs was $260,000, while the projected costs of preventable ADEs causing admission were $3.8 million. The rate of admissions to the mental health center caused by ADEs was higher than for other settings at 13.6%, with a cost of preventable ADEs of $1.3 million. Patient noncompliance was judged to be the cause of the 69% of the ADEs causing admission. Seventy-one percent of the serious medication errors occurred at the prescribing stage of the medication-use process. ADEs were frequent, costly, and often preventable and resulted in many admissions to a mental health center.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Errores de Medicación , Servicio de Farmacia en Hospital/economía , Costos y Análisis de Costo , Hospitalización/economía , Hospitalización/estadística & datos numéricos , Humanos , Errores de Medicación/economía , Errores de Medicación/prevención & control , Errores de Medicación/estadística & datos numéricos , New Mexico/epidemiología , Servicio de Farmacia en Hospital/estadística & datos numéricos , Índice de Severidad de la Enfermedad
5.
Brain ; 124(Pt 3): 493-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11222449

RESUMEN

Matrix metalloproteinases (MMPs) are increased in the CSF of patients with multiple sclerosis. Devic's neuromyelitis optica (DNO) is a demyelinating syndrome that involves the optic nerve and cervical cord but differs pathologically from multiple sclerosis. Therefore, we hypothesized that the type of inflammatory reaction that causes MMPs to be elevated in multiple sclerosis would be absent in patients with DNO. CSF was collected from 23 patients with relapsing-remitting or secondary progressive multiple sclerosis, all of whom were experiencing acute symptoms, from seven patients with DNO, and from seven normal volunteers. Diagnoses were made according to current criteria on the basis of clinical manifestations, imaging results and CSF studies. IgG synthesis was increased in the CSF of multiple sclerosis patients but not in that of DNO patients. Zymography, reverse zymography and ELISA (enzyme-linked immunosorbent assay) were used to measure gelatinase A (MMP-2), gelatinase B (MMP-9) and tissue inhibitors of metalloproteinases (TIMPs). Zymograms showed that multiple sclerosis patients had elevated MMP-9 compared with DNO patients and controls (P: < 0.05). TIMP-1 and TIMP-2 levels were similar in all three groups. We conclude that multiple sclerosis patients have higher MMP-9 levels in the CSF than patients with DNO, which supports the different pathological mechanisms of these diseases.


Asunto(s)
Metaloproteinasas de la Matriz/líquido cefalorraquídeo , Esclerosis Múltiple/líquido cefalorraquídeo , Neuromielitis Óptica/líquido cefalorraquídeo , Inhibidores Tisulares de Metaloproteinasas/líquido cefalorraquídeo , Humanos , Metaloproteinasa 2 de la Matriz/líquido cefalorraquídeo , Metaloproteinasa 9 de la Matriz/líquido cefalorraquídeo , Inhibidor Tisular de Metaloproteinasa-2/líquido cefalorraquídeo
6.
Neurocase ; 7(6): 515-21, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11788743

RESUMEN

Gerstmann syndrome (GS) comprises four interlaced neuropsychological symptoms including finger agnosia, right-left confusion, agraphia, and acalculia. While GS is commonly associated with focal lesions to the region of the left angular gyrus, it has also been associated with numerous diffuse etiologies including atrophy, alcoholism, carbon monoxide poisoning, lead intoxication and anaphylactic shock. Thus, a vigorous debate has emerged as to whether GS represents a syndrome arising from general brain decline or a distinct and localizing lesion. We report a right-handed patient who developed neuropsychological dysfunction secondary to systemic lupus erythematosus (SLE). Neuropsychological evaluation found the patient to exhibit symptoms consistent with the GS tetrad, as well as general cognitive decline. Magnetic resonance imaging revealed a distinct focal lesion of the left parieto-occipital white matter underlying the angular gyrus as well as diffuse atrophy. (1)H-magnetic resonance spectroscopy revealed substantial metabolic derangement in a voxel placed within the visible lesion, although substantial metabolic derangement was observed in regions remote from the focal pathology. Thus, GS in this first case in SLE would appear to comprise a focal neurological tetrad of disorders within a more general pattern of cognitive decline and metabolic derangement.


Asunto(s)
Ácido Aspártico/análogos & derivados , Síndrome de Gerstmann/diagnóstico , Lupus Eritematoso Sistémico/diagnóstico , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Pruebas Neuropsicológicas , Adulto , Agrafia/diagnóstico , Agrafia/psicología , Apraxias/diagnóstico , Apraxias/psicología , Ácido Aspártico/metabolismo , Atrofia , Infarto Cerebral/diagnóstico , Infarto Cerebral/psicología , Colina/metabolismo , Dominancia Cerebral/fisiología , Metabolismo Energético/fisiología , Femenino , Síndrome de Gerstmann/psicología , Humanos , Lupus Eritematoso Sistémico/psicología , Lóbulo Occipital/patología , Lóbulo Parietal/patología
9.
J Cell Biol ; 150(5): 963-74, 2000 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-10973988

RESUMEN

Although maturation/M phase promoting factor (MPF) can activate autonomously in Xenopus egg cytoplasm, indirect evidence suggests that nuclei and centrosomes may focus activation within the cell. We have dissected the contribution of these structures to MPF activation in fertilized eggs and in egg fragments containing different combinations of nuclei, centrosomes, and microtubules by following the behavior of Cdc2 (the kinase component of MPF), the regulatory subunit cyclin B, and the activating phosphatase Cdc25. The absence of the entire nucleus-centrosome complex resulted in a marked delay in MPF activation, whereas the absence of the centrosome alone caused a lesser delay. Nocodazole treatment to depolymerize microtubules through first interphase had an effect equivalent to removing the centrosome. Furthermore, microinjection of isolated centrosomes into anucleate eggs promoted MPF activation and advanced the onset of surface contraction waves, which are close indicators of MPF activation and could be triggered by ectopic MPF injection. Finally, we were able to demonstrate stimulation of MPF activation by the nucleus-centriole complex in vitro, as low concentrations of isolated sperm nuclei advanced MPF activation in cycling cytoplasmic extracts. Together these results indicate that nuclei and microtubule asters can independently stimulate MPF activation and that they cooperate to enhance activation locally.


Asunto(s)
Núcleo Celular/fisiología , Centrosoma/fisiología , Factor Promotor de Maduración/metabolismo , Microtúbulos/fisiología , Oocitos/fisiología , Animales , Proteína Quinasa CDC2/metabolismo , Núcleo Celular/efectos de los fármacos , Ciclina B/metabolismo , Citoplasma/fisiología , Femenino , Fertilización , Humanos , Linfocitos/fisiología , Linfocitos/ultraestructura , Microtúbulos/efectos de los fármacos , Mitocondrias/fisiología , Mitocondrias/ultraestructura , Nocodazol/farmacología , Oocitos/citología , Oocitos/efectos de los fármacos , Proteínas Recombinantes de Fusión/metabolismo , Xenopus laevis
10.
Mult Scler ; 6(4): 255-66, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10962546

RESUMEN

In a randomized, placebo-controlled, double-blind study, glatiramer acetate (Copaxone) reduced the relapse rate and slowed accumulation of disability for patients with relapsing - remitting multiple sclerosis. Of the original 251 patients randomized to receive glatiramer acetate or placebo, 208 chose to continue in an open-label study with all patients receiving active drug. The majority of the original double-blind cohort continues to receive glatiramer acetate by daily subcutaneous injection and are evaluated at 6-month intervals and during suspected relapse. The data reported here are from approximately 6 years of organized evaluation, including the double-blind phase of up to 35 months and the open-label phase of over 36 months. Daily subcutaneous injections of 20 mg glatiramer acetate were well tolerated. The mean annual relapse rate of the patients who received glatiramer acetate since randomization and continued into the open-label study was 0.42 (95% confidence interval (CI), CI=0.34 - 0.51). The rate per year has continued to drop and for the sixth year is 0.23. Of the group who have received glatiramer acetate without interruption for 5 or more years, 69.3% were neurologically unchanged or have improved from baseline by at least one step on the Expanded Disability Status Scale (EDSS). Patients who left the open-label phase were surveyed by questionnaire. The majority responded, providing information about their current status and reasons for dropping out. This study demonstrates the sustained efficacy of glatiramer acetate in reducing the relapse rate and in slowing the accumulation of disability in patients with relapsing forms of multiple sclerosis. Multiple Sclerosis (2000) 6 255 - 266


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Péptidos/uso terapéutico , Adyuvantes Inmunológicos/efectos adversos , Adulto , Estudios de Cohortes , Personas con Discapacidad , Método Doble Ciego , Femenino , Acetato de Glatiramer , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Sistema Nervioso/fisiopatología , Pacientes Desistentes del Tratamiento , Péptidos/efectos adversos , Factores de Tiempo
11.
J Neuroimaging ; 10(4): 209-15, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11147399

RESUMEN

The authors compared the frequency of paranasal sinus inflammatory changes (SIC) on brain magnetic resonance imaging (MRI) obtained from 23 patients with new onset acute optic neuritis (ON) and 48 control patients who underwent outpatient MRI of the brain for reasons other than ON. The authors found a higher frequency of paranasal SIC in patients with ON (83%) than in controls (54%) (p = 0.02). The distribution of paranasal SIC (in ON and in controls) was maxillary (83% and 52%), ethmoid (4% and 2%), frontal (9% and 14%), and sphenoid (4% and 10%). Frequency of the maxillary SIC was significantly higher (p = 0.02) in patients with ON than in controls. Further evaluation of maxillary paranasal SIC with a grading system showed the presence of thickened mucosal lining of the sinuses (grade I) in 17% (ON) and 23% (controls), mucous retention cysts within the sinuses (grade II) in 48% (ON) and 25% (controls), and severe mucosal thickening with complete or near-complete filling of the sinus or an air-fluid level within the sinus (grade III) in 17% (ON) and 4% (controls). Combined frequency of grade II and grade III SIC was significantly higher in the ON group than in controls (p = 0.005), as was the frequency of grade III SIC alone (p = 0.02). Grade I SIC did not significantly differ between the groups. There was a trend (p = 0.09) toward a higher prevalence of bilateral sinus inflammatory changes in patients with bilateral ON. These findings suggest that ON may be associated with sinus inflammatory changes.


Asunto(s)
Imagen por Resonancia Magnética , Neuritis Óptica/diagnóstico , Sinusitis/diagnóstico , Enfermedad Aguda , Adolescente , Adulto , Análisis de Varianza , Encéfalo/patología , Preescolar , Medios de Contraste , Sinusitis del Etmoides/diagnóstico , Femenino , Sinusitis Frontal/diagnóstico , Gadolinio , Humanos , Masculino , Sinusitis Maxilar/diagnóstico , Persona de Mediana Edad , Mucocele/diagnóstico , Membrana Mucosa/patología , Estudios Retrospectivos , Sinusitis del Esfenoides/diagnóstico , Estadísticas no Paramétricas
12.
J Rheumatol ; 26(1): 81-5, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9918245

RESUMEN

OBJECTIVE: To determine the relationship between neurochemical markers of brain injury and brain dysfunction associated with systemic lupus erythematosus (SLE). METHODS: Patients with SLE (n = 12) were studied using magnetic resonance spectroscopic imaging at 1.5 Tesla to determine neurochemistry and a neurocognitive testing battery to determine brain dysfunction. N-acetylaspartate (NAA), creatine (Cre), and choline (Cho) concentrations were measured in white (WM) and gray (GM) matter and expressed as the ratios NAA/Cho, NAA/Cre, and Cho/Cre. Neurocognitive testing results were expressed as a composite z score. Disease activity was quantified by SLE Disease Activity Index (SLEDAI) and disease injury by Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology Damage Index. RESULTS: Neurochemical measures of brain injury were correlated with neurocognitive testing z scores: NAA/Cho in WM (r = 0.77, p = 0.003) and GM (r = 0.67, p = 0.017); WM Cho/Cre also correlated with total z score (r = -0.74, p = 0.006). Neurometabolite ratios and SLICC were correlated: GM NAA/Cho (r = -0.70, p = 0.011 ) and NAA/Cre (r = -0.71, p = 0.01) and WM Cho/Cre (r = 0.66, p = 0.02). Correlations between neurometabolite ratios and SLEDAI did not reach significance. CONCLUSION: Brain function is closely correlated with brain injury assessed noninvasively by proton magnetic resonance spectroscopy. This important finding further supports the use of magnetic resonance spectroscopy to evaluate brain injury in SLE.


Asunto(s)
Encéfalo/metabolismo , Trastornos del Conocimiento/etiología , Lupus Eritematoso Sistémico/complicaciones , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Encéfalo/patología , Encéfalo/fisiopatología , Colina/metabolismo , Trastornos del Conocimiento/metabolismo , Creatina/metabolismo , Femenino , Humanos , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/patología , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
13.
Neurology ; 50(3): 701-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9521260

RESUMEN

When 251 relapsing-remitting patients with multiple sclerosis were randomized to receive daily subcutaneous injections of glatiramer acetate, previously called copolymer 1 (Copaxone; n = 125) or placebo (n = 126) for 24 months, there were no laboratory abnormalities associated with glatiramer acetate treatment and it was well tolerated with few side effects. Patients receiving glatiramer acetate had significantly fewer relapses and were more likely to be neurologically improved, whereas those receiving placebo were more likely to worsen. This study was extended for 1 to 11 months (mean of 5.2 months for the glatiramer acetate group and 5.9 months for the placebo group). The blinding and study conditions used during the core 24-month study were unchanged throughout the extension. The results of this extension study confirm the excellent tolerance and safety profile of glatiramer acetate for injection. The clinical benefit of glatiramer acetate for both the relapse rate and for neurologic disability was sustained at the end of the extension trial.


Asunto(s)
Inmunosupresores/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Péptidos/uso terapéutico , Adulto , Evaluación de la Discapacidad , Método Doble Ciego , Acetato de Glatiramer , Humanos , Inmunosupresores/efectos adversos , Esclerosis Múltiple/fisiopatología , Sistema Nervioso/fisiopatología , Péptidos/efectos adversos , Recurrencia , Análisis de Supervivencia
14.
Biol Psychiatry ; 43(4): 263-9, 1998 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-9513735

RESUMEN

BACKGROUND: Schizophrenia is commonly considered a neurodevelopmental disorder. Our aim was to determine whether the proton magnetic resonance spectroscopic (1H-MRS) changes seen in adults with schizophrenia are displayed in children at risk for developing schizophrenia. METHODS: Children with symptoms of schizophrenia-spectrum disorders (n = 16; mean age = 132 months) and a comparison group (n = 12; mean age 130 months) took part in a 1H-MRS study of the left frontal lobe. Areas of peaks from N-acetylaspartate (NAA), choline (Cho), and creatine (Cre) were determined and ratios of NAA/Cre and Cho/Cre calculated and compared between groups. RESULTS: The mean ratio of NAA/Cre was significantly lower in schizophrenia-spectrum subjects than the comparison group (1.67 vs. 1.92; p < .05). Medication status did not affect results in schizophrenia-spectrum subjects. CONCLUSIONS: Our findings suggest that the metabolic changes associated with adult schizophrenia are observed in children with some or all of the symptoms of schizophrenia, supporting a neurodevelopmental theory for schizophrenia.


Asunto(s)
Lóbulo Frontal/patología , Esquizofrenia/patología , Antipsicóticos/uso terapéutico , Química Encefálica/fisiología , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Esquizofrenia/tratamiento farmacológico
15.
Eur J Biochem ; 247(2): 518-25, 1997 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9266693

RESUMEN

We have analysed the recircularisation of plasmid DNA, cut with two different endonucleases to generate non-homologous DNA ends, in extracts of unfertilised eggs and oocytes of Xenopus. We found that the capacity to join non-homologous DNA ends, generating diagnostic covalently closed monomer circles, appeared during oocyte maturation at the time of germinal vesicle breakdown. This enzyme function was post-translationally activated in oocyte extracts incubated with unfertilised egg extract containing active cdc2/cyclin B, or by incubation with purified cdc2/cyclin B. Dephosphorylation of egg proteins by alkaline phosphatase inhibited the ability to join non-homologous DNA ends. We show that most linear non-homologous DNA ends repaired to form closed-circular supercoiled monomers, are joined without loss of nucleotides. Following partial purification, the activity was inhibited by inhibitors of poly(ADP-Rib) polymerase, an enzyme that is inactive in oocytes, but phosphorylated and activated during maturation. Competitive inhibition of poly(ADP-Rib) polymerase by > 50 microM 3-aminobenzamide prevented the joining of both matched and non-homologous DNA ends. We conclude that post-translational phosphorylation provides one route by which end-joining of non-homologous DNA can be regulated.


Asunto(s)
ADN Ligasas/metabolismo , Oocitos/fisiología , Plásmidos/metabolismo , Procesamiento Proteico-Postraduccional , Animales , Secuencia de Bases , Benzamidas/farmacología , Proteína Quinasa CDC2/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , ADN Ligasa (ATP) , Embrión no Mamífero/metabolismo , Femenino , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/metabolismo , Óvulo/fisiología , Fosforilación , Poli(ADP-Ribosa) Polimerasas/metabolismo , Moldes Genéticos , Extractos de Tejidos/metabolismo , Xenopus laevis
16.
Psychiatry Res ; 76(1): 1-13, 1997 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-9498305

RESUMEN

Children with symptoms of schizophrenia-spectrum disorder (N = 20) were compared to controls (N = 20) matched for age and socioeconomic status. Structural brain abnormalities were assessed with magnetic resonance imaging and functional brain abnormalities with neuropsychological tests. Children with schizophrenia-spectrum disorder had smaller amygdala and temporal cortex volumes, along with reduced callosal areas and an unusual pattern of neuroanatomic asymmetries. No differences were noted in overall brain volume, ventricular volume, hippocampal volume, or frontal area. Schizophrenia-spectrum children were also characterized by deficits in all neuropsychological functions examined. Some types of verbal memory and frontal lobe skills were especially deficient. These results support the hypothesis that children with schizophrenia-spectrum disorder have significant brain abnormalities, similar in some ways to those seen in adult schizophrenics. In conjunction with recent primate studies, the current results draw attention to the role of the amygdala as one relevant factor in the pathogenesis of schizophrenia.


Asunto(s)
Encéfalo/anomalías , Discapacidades del Desarrollo/complicaciones , Esquizofrenia/diagnóstico , Niño , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Esquizofrenia/etiología
17.
Neurology ; 46(6): 1626-32, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8649561

RESUMEN

Contrast-enhanced MRI in patients with MS shows that increased permeability of the blood-brain barrier (BBB) commonly occurs. The changes in capillary permeability often precede T2-weighted MRI evidence of tissue damage. In animal studies, intracerebral injection of the matrix metalloproteinase (MMP) 72-kDa type IV collagenase (gelatinase A) opens the BBB by disrupting the basal lamina around capillaries. Steroids affect production of endogenous MMPs and tissue inhibitors to metalloproteinases (TIMPs). To determine the role of MMP activity in BBB damage during acute exacerbations of MS, we measured MMPs in the CSF of patients with MS. Patients (n = 7) given steroids to treat an acute episode of MS had CSF sampled before and after 3 days of methylprednisolone (1 g/day). Patients had a graded neurologic examination and gadolinium-enhanced MRI before treatment. CSF studies included total protein, cell count, and a demyelinating profile. We measured levels of MMPs, urokinase-type plasminogen activator (uPA), and TIMPs by zymography, reverse zymography, and Western blots. The MMP, 92-kDa type IV collagenase (gelatinase B), fell from 216 +/- 70 before steroids to 54 +/- 26 relative lysis zone units (p < 0.046) after treatment. Similarly, uPA dropped from 3880 +/- 800 to 2655 +/- 353 (p < 0.03). Four patients with gadolinium enhancement on MRI had the most pronounced drop in gelatinase B and uPA. Western immunoblots showed an increase in a complex of gelatinase B and TIMPs after treatment, suggesting an increase in a TIMP (p < 0.05). Reverse zymography of CSF samples showed that steroids increased a TIMP with a molecular weight similar to that of mouse TIMP-3 (p = 0.053). Our results suggest that increased gelatinase B is associated with an open BBB on MRI. Steroids may improve capillary function by reducing activity of gelatinase B and uPA and increasing levels of TIMPs.


Asunto(s)
Antiinflamatorios/uso terapéutico , Enfermedades Autoinmunes/enzimología , Barrera Hematoencefálica , Proteínas del Líquido Cefalorraquídeo/análisis , Metaloendopeptidasas/líquido cefalorraquídeo , Metilprednisolona/uso terapéutico , Esclerosis Múltiple/enzimología , Enfermedad Aguda , Enfermedades Autoinmunes/líquido cefalorraquídeo , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/patología , Colagenasas/líquido cefalorraquídeo , Gelatinasas/líquido cefalorraquídeo , Glicoproteínas/líquido cefalorraquídeo , Humanos , Imagen por Resonancia Magnética , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Inhibidores Tisulares de Metaloproteinasas , Activador de Plasminógeno de Tipo Uroquinasa/líquido cefalorraquídeo
18.
J Cell Sci ; 109 ( Pt 6): 1173-84, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8799808

RESUMEN

The capacity to initiate DNA replication appears during oocyte maturation in Xenopus. Initiation of S phase is driven by several components which include active cyclin/cdk complexes. We have identified three Xenopus cyclin E clones showing 59% amino acid identity with human cyclin E. The recruitment of cyclin E mRNA, like cdk2 mRNA, into the polysomal fraction during oocyte maturation, results in the accumulation of the corresponding proteins in unfertilized eggs. Cyclin E mRNA remains polyadenylated during cleavage and anti-cyclin E antibodies detect Xlcyclin E in embryonic nuclei at this time. Cdk2 protein is necessary for the phosphorylation of radiolabelled cyclin E added to egg extracts. Radiolabelled Xlcyclin E enters interphase nuclei and, though stable through interphase and mitosis, is not associated with condensed mitotic chromatin. In egg extracts, endogenous Xlcyclin E rapidly associates with nuclei before S phase and remains nuclear throughout interphase, becoming nucleoplasmic in G2/prophase. Under conditions where initiation of replication is limiting in extracts, Xlcyclin E associates only with those nuclei that undergo S phase. These features are entirely consistent with the view that Xlcyclin E is required for initiation of S phase.


Asunto(s)
Quinasas CDC2-CDC28 , Ciclinas/metabolismo , Replicación del ADN , Oocitos/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Núcleo Celular/metabolismo , Clonación Molecular , Quinasa 2 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/genética , ADN Complementario/genética , Femenino , Humanos , Datos de Secuencia Molecular , Oocitos/citología , Oocitos/crecimiento & desarrollo , Fosforilación , Poli A/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Fase S , Xenopus , Proteínas de Xenopus
19.
J Neurol Sci ; 134(1-2): 207-9, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8747868

RESUMEN

Sarcomatous metastasis to the central nervous is generally considered uncommon and rarely shows evidence of hemorrhage. Consequently, patients with fibrosarcoma are rarely screened for metastatic disease in the central nervous system. We present a case of fibrosarcoma with metastasis to brain accompanied by overt hemorrhage into the tumor. It is suggested that patients with fibrosarcoma be routinely screened for metastasis to the central nervous system and that sarcomatous metastasis be considered in the differential diagnosis of hemorrhagic CNS tumors.


Asunto(s)
Neoplasias Encefálicas/secundario , Hemorragia Cerebral/complicaciones , Fibrosarcoma/secundario , Anciano , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/diagnóstico , Hemorragia Cerebral/diagnóstico , Diagnóstico Diferencial , Femenino , Fibrosarcoma/complicaciones , Fibrosarcoma/diagnóstico , Humanos , Imagen por Resonancia Magnética
20.
J Cell Sci ; 108 ( Pt 11): 3557-68, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8586667

RESUMEN

Activation of p34cdc2 kinase is essential for entry into mitosis while subsequent deactivation and cyclin degradation are associated with exit. In Xenopus embryos, both of these phases are regulated by post-translation modifications and occur spontaneously on incubation of extracts prepared late in the first cell cycle. Even though high levels of calcium buffer were initially used to prepare these extracts, we found that free calcium levels in them remained in the observed physiological range (200-500 nM). Further addition of calcium buffers only slightly reduced free calcium levels, but inhibited histone H1 (cdc2A) kinase deactivation and cyclin degradation. Higher buffer concentrations slowed the kinase activation phase. Reducing the free buffer concentration by premixing with calcium reversed the effects of the buffer, indicating that the inhibitory effects arose from the calcium-chelating properties of the buffer rather than non-specific side effects. Furthermore, additions of calcium buffer at the end of the H1 kinase activation phase did not prevent deactivation. From these results, and the order of effectiveness of different calcium buffers in disrupting the H1 kinase cycle, we suggest that local transient increases in free calcium influence the rate of cdc2 kinase activation and are required to initiate the pathway leading to cyclin degradation and kinase inactivation in mitotic cell cycles.


Asunto(s)
Proteína Quinasa CDC2/metabolismo , Calcio/fisiología , Ciclinas/metabolismo , Óvulo/enzimología , Animales , Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Proteínas Quinasas Dependientes de Calcio-Calmodulina/farmacología , Extractos Celulares/fisiología , Quelantes/farmacología , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Activación Enzimática/efectos de los fármacos , Femenino , Interfase/fisiología , Factor Promotor de Maduración/metabolismo , Mitosis/fisiología , Óvulo/citología , Péptidos/farmacología , Fosforilación , Profase/fisiología , Xenopus
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