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1.
Cureus ; 16(4): e57419, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38694643

RESUMEN

Creutzfeldt-Jakob disease (CJD) constitutes an aggressively advancing, terminal neurodegenerative condition classified within the spectrum of transmissible spongiform encephalopathies. The difficulty in establishing a diagnosis before death arises from the condition's rarity and the resulting limited level of suspicion attributed to it. The polymorphic nature of CJD symptoms contributes to the challenge of early diagnostic recognition. Emotional and behavioral changes have been well documented, but the initial presentation of euphoria has not been documented. Here, we present the case of a female patient who was experiencing an unusual state of euphoria followed by intermittently altered mental status. She was ultimately diagnosed with sporadic CJD, discharged home on hospice, and died within six months of discharge.

3.
Artículo en Inglés | MEDLINE | ID: mdl-32087851

RESUMEN

Bioflavonoids have a similar chemical structure to etoposide, the well-characterized topoisomerase II (Top2) poison, and evidence shows that they also induce DNA double-strand breaks (DSBs) and promote genome rearrangements. The purpose of this study was to determine the kinetics of bioflavonoid-induced DSB appearance and repair, and their dependence on Top2. Cells were exposed to bioflavonoids individually or in combination in the presence or absence of the Top2 catalytic inhibitor dexrazoxane. The kinetics of appearance and repair of γH2AX foci were measured. In addition, the frequency of resultant MLL-AF9 breakpoint cluster region translocations was determined. Bioflavonoids readily induced the appearance of γH2AX foci, but bioflavonoid combinations did not act additively or synergistically to promote DSBs. Myricetin-induced DSBs were mostly reduced by dexrazoxane, while genistein and quercetin-induced DSBs were only partially, but significantly, reduced. By contrast, luteolin and kaempferol-induced DSBs increased with dexrazoxane pre-treatment. Sensitivity to Top2 inhibition correlated with a significant reduction of bioflavonoid-induced MLL-AF9 translocations. These data demonstrate that myricetin, genistein, and quercetin act most similar to etoposide although with varying Top2-dependence. By contrast, luteolin and kaempferol have distinct kinetics that are mostly Top2-independent. These findings have implications for understanding the mechanisms of bioflavonoid activity and the potential of individual bioflavonoids to promote chromosomal translocations. Further, they provide direct evidence that specific Top2 inhibitors or targeted drugs could be developed that possess less leukemic potential or suppress chromosomal translocations associated with therapy-related and infant leukemias.


Asunto(s)
Reparación del ADN/efectos de los fármacos , Flavonoides/toxicidad , Genisteína/toxicidad , Quempferoles/toxicidad , Luteolina/toxicidad , Quercetina/toxicidad , Animales , Línea Celular , Puntos de Rotura del Cromosoma/efectos de los fármacos , Cromosomas de los Mamíferos/efectos de los fármacos , ADN/química , Roturas del ADN de Doble Cadena/efectos de los fármacos , ADN-Topoisomerasas de Tipo II/genética , ADN-Topoisomerasas de Tipo II/metabolismo , Dexrazoxano/farmacología , Etopósido/toxicidad , Histonas/genética , Histonas/metabolismo , Ratones , Células Madre Embrionarias de Ratones/efectos de los fármacos , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/ultraestructura , Inhibidores de Topoisomerasa II/farmacología , Translocación Genética/efectos de los fármacos
4.
J Nucl Cardiol ; 27(5): 1521-1532, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-30132187

RESUMEN

BACKGROUND: In patients undergoing regadenoson SPECT myocardial perfusion imaging (MPI), the prognostic value of ischemic ST-segment depression (ST↓) and the optimal ST↓ threshold have not been studied. METHODS: A retrospective cohort study of consecutive patients referred for regadenoson stress MPI was conducted. Patients with uninterpretable ECG were excluded. Two diagnostic thresholds of horizontal or downsloping ST↓ were studied, ≥ 0.5 mm and ≥ 1.0 mm. The primary endpoint was the composite major adverse cardiac events (MACE) of cardiac death, myocardial infarction, or coronary revascularization. RESULTS: Among 8615 subjects (mean age 62 ± 13 years; 55% women), 89 (1.0%) had ST↓ ≥ 1.0 mm and 133 (1.5%) had ST↓ ≥ 0.5 mm. Regadenoson-induced ST↓ was more common in women (P < .001). Mean follow-up was 2.5 ± 2.2 years. After multivariate adjustment, ST↓ ≥ 1.0 mm was associated with a non-significant increase in MACE risk (P = .069), irrespective to whether MPI was abnormal (P = .162) or normal (P = .214). Ischemic ST↓ ≥ 0.5 mm was independently associated with MACE in the entire cohort (HR 2.14; CI 1.38-3.32; P = .001), whether MPI is normal (HR 2.07; CI 1.07-4.04; P = .032) or abnormal (HR 2.24; CI 1.23-4.00; P = .007), after adjusting for clinical and imaging covariates. An ST↓ threshold of ≥ 0.5 mm provided greater incremental prognostic value beyond clinical and imaging parameters (Δχ2 = 12.78; P < .001) than ≥ 1.0 mm threshold (Δχ2 = 3.72; P = .093). CONCLUSION: Regadenoson-induced ischemic ST↓ is more common in women and it provides a modest independent prognostic value beyond MPI and clinical parameters. ST↓ ≥ 0.5 mm is a better threshold than ≥ 1.0 mm to define ECG evidence for regadenoson-induced myocardial ischemia.


Asunto(s)
Agonistas del Receptor de Adenosina A2/farmacología , Electrocardiografía , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/fisiopatología , Purinas/farmacología , Pirazoles/farmacología , Anciano , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Imagen de Perfusión Miocárdica , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Tomografía Computarizada de Emisión de Fotón Único
5.
Environ Mol Mutagen ; 60(2): 154-167, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30387535

RESUMEN

Infant acute leukemias are aggressive and characterized by rapid onset after birth. The majority harbor translocations involving the MLL gene with AF9 as one of its most common fusion partners. MLL and AF9 loci contain breakpoint cluster regions (bcrs) with sequences hypothesized to be targets of topoisomerase II inhibitors that promote translocation formation. Overlap of MLL bcr sequences associated with both infant acute leukemia and therapy-related leukemia following exposure to the topoisomerase II inhibitor etoposide led to the hypothesis that exposure during pregnancy to biochemically similar compounds may promote infant acute leukemia. We established a reporter system to systematically quantitate and stratify the potential for such compounds to promote chromosomal translocations between the MLL and AF9 bcrs analogous to those in infant leukemia. We show bioflavonoids genistein and quercetin most biochemically similar to etoposide have a strong association with MLL-AF9 bcr translocations, while kaempferol, fisetin, flavone, and myricetin have a weak but consistent association, and other compounds have a minimal association in both embryonic stem (ES) and hematopoietic stem cell (HSC) populations. The frequency of translocations induced by bioflavonoids at later stages of myelopoiesis is significantly reduced by more than one log. The MLL and AF9 bcrs are sensitive to these agents and recombinogenic independent of their native context suggesting bcr sequences themselves are drivers of illegitimate DNA repair reactions and translocations, not generation of functional oncogenic fusions. This system provides for rapid systematic screening of relative risk, dose dependence, and combinatorial impact of multitudes of dietary and environmental exposures on MLL-AF9 translocations. Environ. Mol. Mutagen. 60: 154-167, 2019. © 2018 Wiley Periodicals, Inc.


Asunto(s)
Flavonoides/toxicidad , Leucemia/genética , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Fusión Oncogénica/genética , Translocación Genética/efectos de los fármacos , Rotura Cromosómica/efectos de los fármacos , Puntos de Rotura del Cromosoma/efectos de los fármacos , Cromosomas/efectos de los fármacos , Cromosomas/genética , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Lactante , Leucemia/inducido químicamente , Leucemia/patología , Embarazo , Medición de Riesgo
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