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1.
Brachytherapy ; 22(6): 728-735, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37574352

RESUMO

PURPOSE: Treatment of locally advanced cervical cancer patients includes chemoradiation followed by brachytherapy. Our aim is to develop a delta radiomics (DRF) model from MRI-based brachytherapy treatment and assess its association with progression free survival (PFS). MATERIALS AND METHODS: A retrospective analysis of FIGO stage IB- IV cervical cancer patients between 2012 and 2018 who were treated with definitive chemoradiation followed by MRI-based intracavitary brachytherapy was performed. Clinical factors together with 18 radiomic features extracted from different radiomics matrices were analyzed. The delta radiomic features (DRFs) were extracted from MRI on the first and last brachytherapy fractions. Support Vector Machine (SVM) models were fitted to combinations of 2-3 DRFs found significant after Spearman correlation and Wilcoxon rank sum test statistics. Additional models were tested that included clinical factors together with DRFs. RESULTS: A total of 39 patients were included in the analysis with a median patient age of 52 years. Progression occurred in 20% of patients (8/39). The significant DRFs using two DRF feature combinations was a model using auto correlation (AC) and sum variance (SV). The best performing three feature model combined mean, AC & SV. Additionally, the inclusion of FIGO stages with the 2- and 3 DRF combination model(s) improved performance compared to models with only DRFs. However, all the clinical factor + DRF models were not significantly different from one another (all AUCs were 0.77). CONCLUSIONS: Our study shows promising evidence that radiomics metrics are associated with progression free survival in cervical cancer.


Assuntos
Braquiterapia , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Braquiterapia/métodos , Imageamento por Ressonância Magnética
2.
Brachytherapy ; 21(1): 94-109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34937684

RESUMO

PURPOSE: Investigate the relationship between dosimetric parameters with local control (LC) and complications following transperineal high-dose rate (HDR) interstitial brachytherapy (ISBT) for gynecologic (GYN) malignancies. METHODS AND MATERIALS: Between 2001 and 2016, 59 patients were treated for primary or recurrent GYN malignancies. Most patients received external beam irradiation, followed by transperineal ISBT via the Syed-Neblett applicator set with CT-based planning. Treatment plans were retrospectively reviewed to evaluate for an association among LC or toxicity with the equivalent dose at 2 Gy per fraction (EQD2) for the clinical target volume (CTV), 0.1 cc (D0.1cc), and 2 cc (D2cc) volumes of the organs at risk (OAR), low/high dose volumes for the OAR and CTV, and ratio of dose at the core vs. the implant periphery. RESULTS: The median follow-up among survivors was 24 months. 34% of patients had a component of local failure and in 12%, this was isolated. Late grade 3 (G3) toxicity occurred in 15% of patients. There were no G4-5 toxicities. Rectal D0.1cc > 75 Gy trended toward significance in predicting the development of non-fistula late G2-3 rectal complications. Bladder D0.1cc > 94 Gy significantly predicted for the development of late G2-3 vesicovaginal fistula formation. The ratio of the total dose at the vaginal surface to the needle periphery above 121% trended in predicting for any complication or fistula formation. CONCLUSIONS: HDR ISBT combined with EBRT achieved LC in 66% of patients with advanced or recurrent GYN cancers. Rectal and bladder D0.1cc doses may be predictive of complications as may the ratio of the implant dose at the core vs. periphery.


Assuntos
Braquiterapia , Neoplasias do Colo do Útero , Braquiterapia/métodos , Feminino , Humanos , Recidiva Local de Neoplasia/etiologia , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Reto/efeitos da radiação , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Wisconsin
3.
Adv Radiat Oncol ; 5(6): 1093-1098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33305069

RESUMO

The increasing role of radiation oncology in optimal cancer care treatment brings to mind the adage that power is never a gift, but a responsibility. A significant part of the responsibility we in radiation oncology bear is how to ensure optimal access to our services. This article summarizes the discussion initiated at the 2019 American Society for Radiation Oncology Annual Meeting educational panel entitled "Improving the Clinical Treatment of Vulnerable Populations in Radiation Oncology: Latin, African American, Native American, and Gender/Sexual Minority Communities." By bringing the discussion to the printed page, we hope to continue the conversation with a broader audience to better define the level of responsibility our field bears in optimizing cancer care to the most vulnerable patient populations within the United States.

4.
J Clin Med ; 4(5): 822-31, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-26239449

RESUMO

Head and neck carcinomas have long been linked to alcohol and tobacco abuse; however, within the last two decades, the human papillomavirus (HPV) has emerged as a third etiology and is specifically associated with head and neck squamous cell carcinomas (HNSCC). In this anatomical region, the oncogenic HPV-16 mediates transformation and immortalization of epithelium, most commonly in the oropharynx. Nevertheless, the recent identification of novel HPV mechanisms thought to be specific to oropharyngeal carcinogenesis has coincided with observations that HPV-associated HNSCC has differing clinical behavior-in terms of natural history, therapeutic response, and prognosis-than HPV-negative head and neck tumors. Taken together with the growing incidence of HPV transmission in younger populations, these discoveries have sparked a rapid expansion in both laboratory and clinical studies on the infection and disease. Herein, we review the clinical characteristics of HPV-associated HNSCC, with particular emphasis on recent advancements in our understanding of the management of this infectious malignancy.

5.
Front Aging Neurosci ; 6: 162, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25100990

RESUMO

Alzheimer's disease (AD) is associated with cognitive and non-cognitive symptoms for which there are currently no effective therapies. We have previously reported that cotinine, a natural product obtained from tobacco leaves, prevented memory loss and diminished amyloid-ß (Aß) plaque pathology in transgenic 6799 mice (Tg6799 mice) when treated prior to the development of the pathology. We have also shown that cotinine reduces depressive-like behavior in normal and chronically stressed C57BL/6 mice. Here, we extend our previous studies by investigating the effects of cotinine on the progression of AD-like pathology, depressive-like behavior, and the mechanisms underlying its beneficial effects in Tg6799 mice when left untreated until after a more advanced stage of the disease's development. The results show that vehicle-treated Tg6799 mice displayed an accentuated loss of working memory and an abundant Aß plaque pathology that were accompanied by higher levels of depressive-like behavior as compared to control littermates. By contrast, prolonged daily cotinine treatment to Tg6799 mice, withheld until after a mid-level progression of AD-like pathology, reduced Aß levels/plaques and depressive-like behavior. Moreover, this treatment paradigm dramatically improved working memory as compared to control littermates. The beneficial effects of cotinine were accompanied by an increase in the expression of the active form of protein kinase B and the postsynaptic density protein 95 in the hippocampi and frontal cortices of Tg6799 mice. This suggests that cotinine halts the progression of AD-like pathology while reducing depressive-like behavior by stimulating signaling pathways supporting synaptic plasticity in Tg6799 mice. The potential use of cotinine to treat cognitive and non-cognitive symptoms of AD is discussed.

6.
CNS Neurosci Ther ; 18(7): 517-23, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22530628

RESUMO

Tobacco smoking has been correlated with a lower incidence of Alzheimer's disease (AD). This negative correlation has been attributed to nicotine's properties. However, the undesired side-effects of nicotine and the absence of clear evidence of positive effects of this drug on the cognitive abilities of AD patients have decreased the enthusiasm for its therapeutic use. In this review, we discuss evidence showing that cotinine, the main metabolite of nicotine, has many of the beneficial effects but none of the negative side-effects of its precursor. Cotinine has been shown to be neuroprotective, to improve memory in primates as well as to prevent memory loss, and to lower amyloid-beta (Aß)) burden in AD mice. In AD, cotinine's positive effect on memory is associated with the inhibition of Aß aggregation, the stimulation of pro-survival factors such as Akt, and the inhibition of pro-apoptotic factors such as glycogen synthase kinase 3 beta (GSK3ß). Because stimulation of the α7 nicotinic acetylcholine receptors (α7nAChRs) positively modulates these factors and memory, the involvement of these receptors in cotinine's effects are discussed. Because of its beneficial effects on brain function, good safety profile, and nonaddictive properties, cotinine may represent a new therapeutic agent against AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cotinina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Doença de Alzheimer/metabolismo , Animais , Cotinina/metabolismo , Humanos , Receptores Nicotínicos/metabolismo
7.
Behav Brain Res ; 228(2): 284-93, 2012 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-22137886

RESUMO

Posttraumatic stress disorder (PTSD) is an anxiety disorder triggered by traumatic events. Symptoms include anxiety, depression and deficits in fear memory extinction (FE). PTSD patients show a higher prevalence of cigarette smoking than the general population. The present study investigated the effects of cotinine, a tobacco-derived compound, over anxiety and contextual fear memory after fear conditioning (FC) in mice, a model for inducing PTSD-like symptoms. Two-month-old C57BL/6J mice were separated into three experimental groups. These groups were used to investigate the effect of pretreatment with cotinine on contextual fear memory and posttreatment on extinction and stability or retrievability of the fear memory. Also, changes induced by cotinine on the expression of extracellular signal-regulated kinase (ERK)1/2 were assessed after extinction in the hippocampus. An increase in anxiety and corticosterone levels were found after fear conditioning. Cotinine did not affect corticosterone levels but enhanced the extinction of contextual fear, decreased anxiety and the stability and/or retrievability of contextual fear memory. Cotinine-treated mice showed higher levels of the active forms of ERK1/2 than vehicle-treated mice after FC. This evidence suggests that cotinine is a potential new pharmacological treatment to reduce symptoms in individuals with PTSD.


Assuntos
Ansiedade/tratamento farmacológico , Condicionamento Psicológico/efeitos dos fármacos , Cotinina/administração & dosagem , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Memória/efeitos dos fármacos , Análise de Variância , Animais , Ansiedade/etiologia , Ansiedade/patologia , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Corticosterona/sangue , Relação Dose-Resposta a Droga , Eletrochoque/efeitos adversos , Comportamento Exploratório/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Reação de Congelamento Cataléptica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Nociceptividade/efeitos dos fármacos , Teste de Desempenho do Rota-Rod , Fatores de Tempo
8.
Brain Res ; 1417: 127-36, 2011 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-21907331

RESUMO

Caffeine intake has been associated with a lower incidence of Alzheimer's disease (AD) in humans. In AD mouse models, caffeine significantly decreases senile plaques and amyloid beta (Aß) levels while also protecting against or reversing cognitive impairment. To understand the mechanism(s) underlying the protective effects of caffeine against AD pathology, we investigated the effects of a two-week treatment with caffeine (3mg/day) in transgenic (APPswe) mice and non-transgenic (NT) mice on signaling factors involved in neuronal plasticity and survival. We evaluated cAMP-dependent protein kinase A (PKA), phospho-cyclic AMP response-element binding protein (phospho-CREB), and the pro-apoptotic protein kinases extracellular signal-regulated kinase 1/2 (phospho-ERK) and phospho-c-Jun N-terminal kinase 1 (phospho-JNK) in the striatum and frontal cortex of caffeine-treated mice. In the striatum, APPswe control mice exhibited a significant decrease in phospho-CREB, as well as significant increases in phospho-JNK and phospho-ERK in comparison to NT mice. Caffeine treatment stimulated PKA activity, increased phospho-CREB levels, and decreased phospho-JNK and phospho-ERK expression in the striatum of APPswe mice, all of which are thought to be beneficial changes for brain function. Even caffeine-treated NT mice exhibited some of these changes in striatum. In the frontal cortex, caffeine did not significantly increase phospho-CREB and PKA activity, but significantly reduced phospho-JNK and phospho-ERK expression in both APPswe and NT mice. These results suggest that caffeine shifts the balance between neurodegeneration and neuronal survival toward the stimulation of pro-survival cascades and inhibition of pro-apoptotic pathways in the striatum and/or cortex, which may contribute to its beneficial effects against AD.


Assuntos
Doença de Alzheimer/enzimologia , Encéfalo/efeitos dos fármacos , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , MAP Quinase Quinase 4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Doença de Alzheimer/patologia , Animais , Western Blotting , Encéfalo/enzimologia , Encéfalo/patologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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