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1.
Brain ; 133(Pt 3): 771-86, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20157015

RESUMEN

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal 'dominant optic atrophy plus' variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.


Asunto(s)
Enfermedades del Sistema Nervioso Central/complicaciones , GTP Fosfohidrolasas/genética , Atrofia Óptica Autosómica Dominante/complicaciones , Adolescente , Adulto , Anciano , Enfermedades del Sistema Nervioso Central/genética , Enfermedades del Sistema Nervioso Central/metabolismo , Enfermedades del Sistema Nervioso Central/patología , Niño , Estudios de Cohortes , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , Familia , Femenino , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Mutación , Atrofia Óptica Autosómica Dominante/genética , Atrofia Óptica Autosómica Dominante/metabolismo , Atrofia Óptica Autosómica Dominante/patología , Fenotipo , Adulto Joven
2.
IEEE Trans Neural Syst Rehabil Eng ; 15(2): 286-94, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17601199

RESUMEN

The potential of computer games peripherals to measure the motor dysfunction in Parkinson's diseases is assessed. Of particular interest is the quantification of bradykinesia. Previous studies used modified or custom haptic interfaces, here an unmodified force feedback joystick and steering wheel are used with a laptop. During testing an on screen cursor moves in response to movements of the peripheral, the user has to track a continuously moving target (pursuit tracking), or move to a predetermined target (step tracking). All tasks use movement in the horizontal axis, allowing use of joystick or steering wheel. Two pursuit tracking tasks are evaluated, pseudo random movement, and a swept frequency task. Two step tracking tasks are evaluated, movement between two or between two of five fixed targets. Thirteen patients and five controls took part on a weekly basis. Patients were assessed for bradykinesia at each session using standard clinical measures. A range of quantitative measures was developed to allow comparison between and within patients and controls using analysis of variance (ANOVA). Both peripherals are capable of discriminating between controls and patients, and between patients with different levels of bradykinesia. Recommendations for test procedures and peripherals are given.


Asunto(s)
Periféricos de Computador , Diagnóstico por Computador/instrumentación , Diagnóstico por Computador/métodos , Hipocinesia/diagnóstico , Destreza Motora , Enfermedad de Parkinson/diagnóstico , Análisis y Desempeño de Tareas , Adulto , Anciano , Femenino , Humanos , Hipocinesia/etiología , Hipocinesia/fisiopatología , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/fisiopatología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Juegos de Video
4.
Neurology ; 55(10): 1579-81, 2000 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-11094122

RESUMEN

Cryoglobulinemia is a rare cause of encephalopathy. The authors report three patients with strikingly similar clinical features of recurrent encephalopathy accompanied by symptoms of gastrointestinal ischemia. In only one patient was cryoglobulinemia ascertained in life during the final illness. The autopsy examinations all showed diffuse cerebral, enteral, and systemic small vessel lesions immunoreactive for immunoglobulins and typical of mixed essential cryoglobulinemia. This unusual relapsing clinical syndrome is readily misinterpreted as of nonorganic origin despite its potentially fatal prognosis.


Asunto(s)
Encefalopatías/fisiopatología , Crioglobulinemia/fisiopatología , Enfermedades Gastrointestinales/fisiopatología , Anciano , Encefalopatías/patología , Crioglobulinemia/patología , Femenino , Enfermedades Gastrointestinales/patología , Humanos , Persona de Mediana Edad , Síndrome
5.
Cancer J ; 6(3): 146-50, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10882329

RESUMEN

The purpose of this article was to evaluate the antitumor effects of a combination chemotherapy program based on ProMACE (prednisone, methotrexate, doxorubicin [Adriamycin], cyclophosphamide, etoposide) followed by a B cell-specific immunotoxin in the treatment of patients with advanced-stage indolent histology non-Hodgkin's lymphomas. We performed a prospective phase II clinical trial in a referral-based patient population. After confirmation of diagnosis and staging evaluation, 44 patients (10 small lymphocytic lymphoma, 27 follicular lymphoma, 7 mantle cell lymphoma; 30 without prior therapy, 14 previously treated) received six cycles of ProMACE-CytaBOM (cytarabine, bleomycin, vincristine [Oncovin], mechlorethamine) combination chemotherapy (with etoposide given orally daily for five days) followed by a 7-day continuous infusion of anti-B4-blocked ricin immunotoxin at 30 microg/kg/day given every 14 days for up to six cycles. A complete response was achieved in 25 of 44 patients (57%), 21 from the chemotherapy alone, 3 converted from partial to complete response with the immunotoxin, and 1 patient became a complete responder after a surgical procedure to remove an enlarged spleen that was histologically negative for lymphoma. With a median follow-up of 5 years, 14 of 25 complete responders have relapsed (56%); median remission duration was 2 years, and overall survival was 61%. Forty-two percent of the complete responders have been in continuous remission for more than 4 years. The median number of courses of immunotoxin delivered was two usually because of the development of human anti-ricin antibodies. ProMACE-CytaBOM plus anti-B4-blocked ricin does not produce durable complete remissions in the majority of patients with indolent lymphoma. However, the remissions appear quite durable (> 4 years) in about 40% of the complete responders.


Asunto(s)
Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica , Inmunoconjugados/uso terapéutico , Inmunotoxinas/uso terapéutico , Linfoma/tratamiento farmacológico , Ricina/uso terapéutico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bleomicina/uso terapéutico , Ciclofosfamida/uso terapéutico , Citarabina/uso terapéutico , Supervivencia sin Enfermedad , Doxorrubicina/uso terapéutico , Etopósido/uso terapéutico , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Linfoma/mortalidad , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/mortalidad , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/mortalidad , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Prednisona/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento , Vincristina/uso terapéutico
6.
Nat Med ; 5(10): 1171-7, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10502821

RESUMEN

Lymphomas express a tumor-specific antigen which can be targeted by cancer vaccination. We evaluated the ability of a new idiotype protein vaccine formulation to eradicate residual t(14;18)+ lymphoma cells in 20 patients in a homogeneous, chemotherapy-induced first clinical complete remission. All 11 patients with detectable translocations in their primary tumors had cells from the malignant clone detectable in their blood by PCR both at diagnosis and after chemotherapy, despite being in complete remission. However, 8 of 11 patients converted to lacking cells in their blood from the malignant clone detectable by PCR after vaccination and sustained their molecular remissions. Tumor-specific cytotoxic CD8+ and CD4+ T cells were uniformly found (19 of 20 patients), whereas antibodies were detected, but apparently were not required for molecular remission. Vaccination was thus associated with clearance of residual tumor cells from blood and long-term disease-free survival. The demonstration of molecular remissions, analysis of cytotoxic T lymphocytes against autologous tumor targets, and addition of granulocyte-monocyte colony-stimulating factor to the vaccine formulation provide principles relevant to the design of future clinical trials of other cancer vaccines administered in a minimal residual disease setting.


Asunto(s)
Antígenos de Neoplasias/inmunología , Vacunas contra el Cáncer/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Idiotipos de Inmunoglobulinas/uso terapéutico , Linfoma Folicular/terapia , Adulto , Anciano , Anticuerpos Antineoplásicos/sangre , Antineoplásicos/uso terapéutico , Vacunas contra el Cáncer/inmunología , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 18 , ADN de Neoplasias/sangre , Quimioterapia Combinada , Femenino , Humanos , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/genética , Linfoma Folicular/inmunología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Inducción de Remisión , Translocación Genética
7.
Clin Immunol ; 90(2): 173-81, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10080828

RESUMEN

We determined whether a classical conditioning paradigm may be used to condition immunologic responses in normal human subjects receiving an optimal immunostimulating dose of recombinant human interferon-gamma (rhIFN-gamma). We conducted a placebo-controlled, double-blind study of 31 normal volunteers in order to determine whether an initially immune-neutral stimulus, oral propylene glycol (PG), could eventually elicit an immune response as a consequence of its being paired with a known immunostimulatory dose and schedule of rhIFN-gamma. Subjects were randomly assigned to one of three groups: (A) rhIFN-gamma injections paired with PG; (B) normal saline injections paired with PG; (C) rhIFN-gamma injections alone. During the 4-week study, subjects received progressively fewer injections so that, by the final week of the study, no injections were given and groups A and B received only PG. The principal outcome measures were serum concentrations of quinolinic acid (QUIN) and neopterin, two nonspecific but sensitive markers of immune activation, and expression of Fc receptors (CD64) on peripheral blood mononuclear cells. RhIFN-gamma injections produced significant and predictable alterations in each of the measured immune parameters. No group B subject made an immune response. Mean serum QUIN levels were significantly higher at the end of week three for subjects in the experimental condition (group A) than for subjects receiving rhIFN-gamma alone (group C) despite receiving identical doses of rhIFN-gamma. Similarly, the predicted decay in mean serum neopterin levels from the end of week 1 to the end of week 2 was seen in group C but not in group A. The exposure of group A to PG blunted the decline of CD64 expression in week four. The data suggest that the pairing of an unconditioned stimulus (rhIFN-gamma) and a conditioned stimulus (PG) permits the conditioned stimulus alone to prolong a cytokine-induced response in normal humans.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Condicionamiento Clásico/fisiología , Interferón gamma/farmacología , Adyuvantes Inmunológicos/administración & dosificación , Adolescente , Adulto , Citocinas/biosíntesis , Método Doble Ciego , Femenino , Humanos , Interferón gamma/administración & dosificación , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad , Neopterin/sangre , Propilenglicol/administración & dosificación , Propilenglicol/farmacología , Ácido Quinolínico/sangre , Receptores de IgG/sangre , Proteínas Recombinantes
9.
Mov Disord ; 13(6): 941-6, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9827619

RESUMEN

In view of the steadily rising demand for treatment of dystonia with botulinum toxin (BT), a relatively expensive neurologic paralytic agent, an exploratory study was undertaken to assess the extent to which dystonia and BT treatment affect the quality of people's lives. One hundred thirty adults with a current diagnosis of dystonia completed two generic measures of health-related quality of life (HRQoL) at regular intervals over a minimum of 6 months. One hundred two participants were receiving regular injections of BT; 28 were not taking BT. The HRQoL instruments used were the EuroQol and the Short Form 36 health survey questionnaire (SF-36). Compared with general population samples, study participants reported greater impairment on all EuroQol and SF-36 dimensions and gave a lower rating to their own health status. Participants with nonfocal dystonia had significantly more problems with usual activities than participants with focal dystonia, and a higher number had problems with mobility and self-care. The groups reported similar levels of pain and emotional well-being. Small improvements in HRQoL were seen after the administration of BT, although few of these were statistically significant. The study results offer further psychometric evidence for the discriminant and construct validity of both the EuroQol and the SF-36.


Asunto(s)
Antidiscinéticos/uso terapéutico , Toxinas Botulínicas/uso terapéutico , Distonía/tratamiento farmacológico , Calidad de Vida , Adulto , Distribución de Chi-Cuadrado , Estudios de Cohortes , Distonía/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Encuestas y Cuestionarios
12.
Mol Microbiol ; 29(3): 835-50, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9723922

RESUMEN

Entry into intestinal epithelial cells is an essential feature in the pathogenicity of Salmonella typhi, which causes typhoid fever in humans. This process requires intact motility and secretion of the invasion-promoting Sip proteins, which are targets of the type III secretion machinery encoded by the inv, spa and prg loci. During our investigations into the entry of S. typhi into cultured epithelial cells, we observed that the secretion of Sip proteins and flagellin was impaired in Vi-expressing strains. We report here that the production of Sip proteins, flagellin and Vi antigen is differentially modulated by the RcsB-RcsC regulatory system and osmolarity. This regulation occurs at both transcriptional and post-translational levels. Under low-osmolarity conditions, the transcription of iagA, invF and sipB genes is negatively controlled by the RcsB regulator, which probably acts in association with the viaB locus-encoded TviA protein. The cell surface-associated Vi polysaccharide, which was maximally produced under these growth conditions, prevented the secretion of Sip proteins and flagellin. As the NaCl concentration in the growth medium was increased, transcription of iagA, invF and sipB was found to be markedly increased, whereas transcription of genes involved in Vi antigen biosynthesis was greatly reduced. The expression of iagA, whose product is involved in invF and sipB transcription, occurred selectively during the exponential growth phase and was maximal in the presence of 300mM NaCl. At this osmolarity, large amounts of Sips and flagellin were secreted in culture supernatants. As expected from these results, and given the essential role of Sip proteins and motility in entry, RcsB and osmolarity modulated the invasive capacity of S. typhi. Together, these findings might reflect the adaptive response of S. typhi to the environments encountered during the different stages of pathogenesis.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Flagelina/genética , Regulación Bacteriana de la Expresión Génica , Complejos Multienzimáticos , Fosfoproteínas Fosfatasas , Polisacáridos Bacterianos/genética , Proteínas Quinasas , Salmonella typhi/genética , Factores de Transcripción/metabolismo , Factores de Virulencia , Antígenos Bacterianos/biosíntesis , Membrana Celular/metabolismo , Proteínas de la Membrana/metabolismo , Concentración Osmolar , Polisacáridos Bacterianos/biosíntesis , Salmonella typhi/fisiología , Transcripción Genética
14.
J Clin Oncol ; 15(11): 3338-46, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9363863

RESUMEN

PURPOSE: To evaluate the efficacy and toxicity of mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy plus mantle-field radiation therapy in the treatment of patients with massive mediastinal Hodgkin's disease of any stage. PATIENTS AND METHODS: Eighty patients presented with Hodgkin's disease and a mediastinal mass greater than one third the greatest chest diameter on chest radiograph. Patients were staged and treated with MOPP alternated with ABVD chemotherapy for a total of six cycles. Patients then received 10 Gy mantle-field radiation therapy delivered to the original extent of disease followed by 25 to 35 Gy to the residual abnormalities. RESULTS: The complete response (CR) rate was 89%. With a median follow-up duration of 10 years, disease-free survival of the complete responders is 78% at 15 years and overall survival is 75% at 15 years. For patients with stage I or II disease, disease-free survival was 76% at 15 years and overall survival was 79%; for those with stage III or IV disease, disease-free survival was 82% at 15 years and overall survival was 64%. Age, stage, sex, B symptoms, number of extranodal sites, lactate dehydrogenase (LDH) levels, erythrocyte sedimentation rate, and platelet count did not influence treatment outcome. Treatment-related pneumonitis was noted in 16% of patients (fatal in one), mainly in those older than age 35 years who received total doses of radiation therapy greater than 42 Gy. Fertility is more often preserved with MOPP/ABVD therapy than with MOPP chemotherapy and there appears to be less pulmonary and cardiac disease than with ABVD chemotherapy. Two patients have developed second solid tumors within radiation ports and one relapsed patient developed acute leukemia after MOPP salvage therapy. CONCLUSION: MOPP/ABVD followed by mantle-field radiation therapy is an effective treatment for all stages of Hodgkin's disease that present with a large mediastinal mass. Our data suggest that the large mediastinal mass is a more dominant determinant of prognosis than Ann Arbor stage or other clinical prognostic factors.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Neoplasias del Mediastino/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Niño , Terapia Combinada , Dacarbazina/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Femenino , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Mecloretamina/administración & dosificación , Neoplasias del Mediastino/radioterapia , Persona de Mediana Edad , Prednisona/administración & dosificación , Procarbazina/administración & dosificación , Estudios Prospectivos , Resultado del Tratamiento , Vinblastina/administración & dosificación , Vincristina/administración & dosificación
15.
Sarcoidosis Vasc Diffuse Lung Dis ; 14(2): 171-2, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9306510

RESUMEN

Sarcoidosis presents only infrequently with stroke or focal neurological deficit and recurrent focal neurological deficit is rarer still. This case report describes a patients presenting with episodic non-fluent dysphasia of abrupt onset occurring during a period of 18 months without evidence of seizure activity or macroscopic granulomatous collection. The case illustrates that the presentation of neurosarcoidosis may mimic classic reversible ischaemic neurological deficit.


Asunto(s)
Afasia/etiología , Trastornos Cerebrovasculares/complicaciones , Sarcoidosis/complicaciones , Adulto , Afasia/diagnóstico , Afasia/tratamiento farmacológico , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Glucocorticoides/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Recurrencia , Sarcoidosis/diagnóstico , Sarcoidosis/tratamiento farmacológico , Hormonas Tiroideas/uso terapéutico
16.
Pharmacoeconomics ; 12(6): 675-84, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10175979

RESUMEN

The dystonias are a group of movement disorders arising from CNS dysfunction and characterised by involuntary and prolonged spasms of muscle contraction. Recently there has been increasing demand for treatment with botulinum toxin (BT), a relatively expensive neurological paralytic agent. As there has been no systematic assessment of patient benefit from BT, this study was undertaken to develop and test a methodology for assessing the cost utility of BT therapy for patients with dystonias. A generic health status instrument, the EuroQOL, was completed at regular intervals over at least 6 months by 130 patients with a current diagnosis of dystonia. A general population tariff was used to calculate quality-adjusted life-year (QALY) gains from BT treatment, and relevant cost data were obtained from patients and medical records. The cost-per-QALY estimates ranged considerably, depending on the type of dystonia, the duration of BT treatment, type of health-related quality-of-life (HR-QOL) tariff used and baseline characteristics of participants. The study findings reflect the general clinical impression of BT: that it can benefit patients with dystonia, but the benefit may be small compared with many treatments for other diseases. The nature of the disease and its cyclical treatment caused practical difficulties in recruiting participants, administering questionnaires and in estimating QALY gains.


Asunto(s)
Toxinas Botulínicas/uso terapéutico , Distonía/tratamiento farmacológico , Adulto , Anciano , Distonía/psicología , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida
17.
J Clin Microbiol ; 34(12): 2963-7, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8940431

RESUMEN

Polyphasic taxonomic methods were employed to characterize a new species of slowly growing, nonpigmented mycobacteria. We propose the name Mycobacterium triplex sp. nov. for this new taxon. Conventional identification testing demonstrated a group of similar organisms that were geographically widespread in the United States. Commercially available nucleic-acid probes specific for the Mycobacterium avium complex were unreactive for these strains. High-performance liquid chromatography analysis of the mycolic acids revealed mycolate profiles that closely resembled Mycobacterium simiae. Comparative 16S rRNA sequence data confirmed the phylogenetic relationship of the strains with the slowly growing mycobacteria. Representative-type strains have been deposited in the American Type Culture Collection as strain ATCC 700071 [corrected].


Asunto(s)
Mycobacterium/clasificación , Mycobacterium/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Secuencia de Bases , Cartilla de ADN/genética , Humanos , Datos de Secuencia Molecular , Mycobacterium/genética , Infecciones por Mycobacterium/epidemiología , Infecciones por Mycobacterium/microbiología , Complejo Mycobacterium avium/clasificación , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Terminología como Asunto , Estados Unidos/epidemiología
19.
J Clin Microbiol ; 34(8): 1939-43, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8818886

RESUMEN

Identification of mycobacteria from BACTEC 12B cultures is achieved in 7 to 21 days by reverse-phase high-performance liquid chromatography (HPLC) using a UV spectrophotometer to detect nonpolar p-bromophenylacyl mycolic acid derivatives. However, cultures grown in BACTEC and other liquid media seldom contain sufficient mycolic acids to permit reliable identification under usual HPLC assay conditions, so the sample size must be increased. Unfortunately, samples prepared from cultures in liquid media such as BACTEC cultures also contain large amounts of extraneous polar and strongly nonpolar contaminants that interfere with the analysis and hasten deterioration of the HPLC column. The contaminants were removed from 10 samples simultaneously by solid-phase extraction (SPE), i.e., by passing the crude suspension containing the mycolic acid derivatives into disposable 500-mg tC18 SPE columns in place of the usual final filtration step used to prepare specimens for HPLC. Fifteen milliliters of 20% (vol/vol) dichloromethane in methanol was passed through the columns (< 3 ml/min) to wash through the undesired contaminants and bind the mycolic acid derivatives. The mycolates were quantitatively eluted in 3 ml of dichloromethane for analysis by HPLC. Treating a panel of 31 strains of frequently isolated mycobacteria by SPE reduced the content of contaminants by 89.3 to 99.9% without altering the chromatographic patterns compared with the same strains grown on conventional solid media and processed without SPE. Peak heights of mycolates prepared from BACTEC cultures were increased from < or = 6 to > or = 25 absorbance milliunits with SPE, sufficient for reliable interpretation by visual inspection of chromatograms obtained with a UV detector. Also, removal of the contaminants improved column longevity.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Mycobacterium/química , Mycobacterium/aislamiento & purificación , Ácidos Micólicos/análisis , Medios de Cultivo , Mycobacterium/crecimiento & desarrollo
20.
Arch Neurol ; 53(8): 814-8, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8759989

RESUMEN

OBJECTIVE: To report the cases of 2 patients who developed the features of radiation encephalopathy 33 and 28 years after cranial irradiation. DESIGN: Case reports; clinical data were available for 2 years in each instance. CONCLUSION: Latent intervals approaching 2 decades have been reported in cases of radiation necrosis following cranial irradiation, but a similar or greater delay before the onset of radiation encephalopathy has not been described previously. This report indicates that a diagnosis of radiation encephalopathy must be considered when any individual who has received cranial irradiation presents with deterioration in intellectual or motor function, whatever the interval.


Asunto(s)
Encefalopatías/etiología , Encéfalo/efectos de la radiación , Irradiación Craneana/efectos adversos , Inteligencia/efectos de la radiación , Adulto , Encefalopatías/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Necrosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X
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