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1.
Ann Neurol ; 78(2): 193-210, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26032020

RESUMO

OBJECTIVE: Migraine is among the most common and debilitating neurological conditions. Familial hemiplegic migraine type 1 (FHM1), a monogenic migraine subtype, is caused by gain-of-function of voltage-gated CaV 2.1 calcium channels. FHM1 mice carry human pathogenic mutations in the α1A subunit of CaV 2.1 channels and are highly susceptible to cortical spreading depression (CSD), the electrophysiologic event underlying migraine aura. To date, however, the mechanism underlying increased CSD/migraine susceptibility remains unclear. METHODS: We employed in vivo multiphoton microscopy of the genetically encoded Ca(2+)-indicator yellow cameleon to investigate synaptic morphology and [Ca(2+)]i in FHM1 mice. To study CSD-induced cerebral oligemia, we used in vivo laser speckle flowmetry and multimodal imaging. With electrophysiologic recordings, we investigated the effect of the CaV 2.1 gating modifier tert-butyl dihydroquinone on CSD in vivo. RESULTS: FHM1 mutations elevate neuronal [Ca(2+)]i and alter synaptic morphology as a mechanism for enhanced CSD susceptibility that we were able to normalize with a CaV 2.1 gating modifier in hyperexcitable FHM1 mice. At the synaptic level, axonal boutons were larger, and dendritic spines were predominantly of the mushroom type, which both provide a structural correlate for enhanced neuronal excitability. Resting neuronal [Ca(2+)]i was elevated in FHM1, with loss of compartmentalization between synapses and neuronal shafts. The percentage of calcium-overloaded neurons was increased. Neuronal [Ca(2+)]i surge during CSD was faster and larger, and post-CSD oligemia and hemoglobin desaturation were more severe in FHM1 brains. INTERPRETATION: Our findings provide a mechanism for enhanced CSD susceptibility in hemiplegic migraine. Abnormal synaptic Ca(2+) homeostasis and morphology may contribute to chronic neurodegenerative changes as well as enhanced vulnerability to ischemia in migraineurs.


Assuntos
Canais de Cálcio Tipo N/genética , Cálcio/metabolismo , Córtex Cerebral/metabolismo , Depressão Alastrante da Atividade Elétrica Cortical/genética , Enxaqueca com Aura/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Animais , Canais de Cálcio Tipo N/metabolismo , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Homeostase/genética , Hidroquinonas/farmacologia , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica , Enxaqueca com Aura/genética , Enxaqueca com Aura/patologia , Mutação , Neurônios/efeitos dos fármacos , Neurônios/patologia , Sinapses/efeitos dos fármacos , Sinapses/patologia
2.
Int J Breast Cancer ; 2015: 213123, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25949828

RESUMO

Objective. This study examined recurrence patterns in breast cancer patients younger than age of 40 and older than age of 75, two groups that are underrepresented in clinical trials and not routinely screened by mammography. Methods. The records of 230 breast cancer patients (n = 125 less than 40 and n = 105 greater than 75) who presented to the Emory University Department of Radiation Oncology for curative treatment between 1997 and 2010 were reviewed. Data recorded included disease presentation, treatment, and areas of locoregional recurrence. Results. Women less than 40 years of age had higher rates of locoregional recurrence (20% versus 7%, P = 0.004) and distant recurrence (18% versus 5%, P = 0.003) than patients above 75 years of age. On multivariate analysis, patient age less than 40 was the only significant predictor of locoregional recurrence (P = 0.018). In a univariate analysis of each age group, receptor status and postlumpectomy radiation were significant predictors of locoregional recurrence-free survival in younger women while mammography screening predicted for distant recurrence-free survival in older patients. Conclusion. The factors identified in our age-stratified analysis highlight patients who are at high risk of locoregional and distant recurrence. Future studies aimed at enhancing therapies in young patients are warranted.

3.
Stroke ; 46(1): 229-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25424478

RESUMO

BACKGROUND AND PURPOSE: Migraine with aura is an established stroke risk factor, and excitatory mechanisms such as spreading depression (SD) are implicated in the pathogenesis of both migraine and stroke. Spontaneous SD waves originate within the peri-infarct tissue and exacerbate the metabolic mismatch during focal cerebral ischemia. Genetically enhanced SD susceptibility facilitates anoxic depolarizations and peri-infarct SDs and accelerates infarct growth, suggesting that susceptibility to SD is a critical determinant of vulnerability to ischemic injury. Because chronic treatment with migraine prophylactic drugs suppresses SD susceptibility, we tested whether migraine prophylaxis can also suppress ischemic depolarizations and improve stroke outcome. METHODS: We measured the cortical susceptibility to SD and ischemic depolarizations, and determined tissue and neurological outcomes after middle cerebral artery occlusion in wild-type and familial hemiplegic migraine type 1 knock-in mice treated with vehicle, topiramate or lamotrigine daily for 7 weeks or as a single dose shortly before testing. RESULTS: Chronic treatment with topiramate or lamotrigine reduced the susceptibility to KCl-induced or electric stimulation-induced SDs as well as ischemic depolarizations in both wild-type and familial hemiplegic migraine type 1 mutant mice. Consequently, both tissue and neurological outcomes were improved. Notably, treatment with a single dose of either drug was ineffective. CONCLUSIONS: These data underscore the importance of hyperexcitability as a mechanism for increased stroke risk in migraineurs, and suggest that migraine prophylaxis may not only prevent migraine attacks but also protect migraineurs against ischemic injury.


Assuntos
Anticonvulsivantes/farmacologia , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Frutose/análogos & derivados , Infarto da Artéria Cerebral Média , Transtornos de Enxaqueca/prevenção & controle , Triazinas/farmacologia , Animais , Isquemia Encefálica , Canais de Cálcio Tipo N/genética , Quimioprevenção , Depressão Alastrante da Atividade Elétrica Cortical/genética , Frutose/farmacologia , Técnicas de Introdução de Genes , Lamotrigina , Camundongos , Acidente Vascular Cerebral , Topiramato
4.
Ann Surg Oncol ; 18(10): 2858-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21442346

RESUMO

PURPOSE: To evaluate disease failure patterns and overall survival (OS) of women with triple-negative (TN) breast cancer who underwent breast-conserving therapy (BCT) and to understand the relationship of TN tumors with other prognostic factors. PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results (SEER) registry identified 562 women diagnosed and/or treated with unilateral invasive breast cancer during 2003-2004 at three Emory hospitals. After medical record review, 193 eligible women, with all tumor types, received BCT. Primary endpoints (local, regional, and distant recurrences) and secondary endpoint (OS) were evaluated using chi-square tests and Cox proportional hazards models. RESULTS: Of the 193 women, 33 (17.1%) had TN tumors and 160 (82.9%) had non-TN tumors. Patient characteristics were similar between the two tumor types; however, tumor grade and use of chemotherapy and hormones differed between the two groups. Median follow-up was 3.4 years; 22 patients had recurrence (12.2%), and 12 died (6.2%). Patients with TN tumors had higher local (12% versus 4% for non-TN) and distant recurrences (15% versus 4% for non-TN) rates (p = 0.01). On multivariate survival analyses, TN status [hazard ratio (HR) 1.8, 95% confidence interval (CI) 1.13-2.93] and African American (AA) race (HR 1.9, 95%CI 1.2-3.07) were independent predictors of inferior OS. CONCLUSIONS: Patients with TN breast cancer showed significant increases in local and distant metastatic recurrence rates after BCT, and TN status and AA race were independent negative predictors of survival. For the future, identification of these high risk features may bring personalized medicine closer to reality.


Assuntos
Neoplasias da Mama/mortalidade , Recidiva Local de Neoplasia/mortalidade , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Antineoplásicos/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/terapia , Estudos Retrospectivos , Programa de SEER , Taxa de Sobrevida , Resultado do Tratamento
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