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1.
Proc Natl Acad Sci U S A ; 119(25): e2118796119, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35704756

RESUMO

Position-effect variegation (PEV) results from the juxtaposition of euchromatic and heterochromatic components of eukaryotic genomes, silencing genes near the new euchromatin/heterochromatin junctions. Silencing is itself heritable through S phase, giving rise to distinctive random patterns of cell clones expressing the genes intermixed with clones in which the genes are silenced. Much of what we know about epigenetic inheritance in the soma stems from work on PEV aimed at identifying the components of the silencing machinery and its mechanism of inheritance. The roles of two central gene activities-the Su(var)3-9-encoded histone H3-lysine-9 methyltransferase and the Su(var)205-encoded methyl-H3-lysine-9 binding protein heterochromatin protein 1 (HP1a)-have been inferred from terminal phenotypes, leaving considerable gaps in understanding of how PEV behaves through development. Here, we investigate the PEV phenotypes of Su(var)3-9 and Su(var)205 mutations in live developing tissues. We discovered that mutation in Su(var)205 compromises the initial establishment of PEV in early embryogenesis. Later gains of heterochromatin-induced gene silencing are possible but are unstable and lost rapidly. In contrast, a strain with mutation in Su(var)3-9 exhibits robust silencing early in development but fails to maintain it through subsequent cell divisions. Our analyses show that, while the terminal phenotypes of these mutations may appear identical, they have arrived at them through different developmental trajectories. We discuss how our findings expand and clarify existing models for epigenetic inheritance of heterochromatin-induced gene silencing.


Assuntos
Homólogo 5 da Proteína Cromobox , Proteínas de Drosophila , Drosophila , Metiltransferases , Animais , Homólogo 5 da Proteína Cromobox/genética , Homólogo 5 da Proteína Cromobox/metabolismo , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Heterocromatina/genética , Lisina/genética , Metiltransferases/genética , Metiltransferases/metabolismo
2.
J Neurooncol ; 161(2): 317-327, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36525165

RESUMO

INTRODUCTION: Few studies have evaluated meningioma patients' longer-term health-related quality of life (HRQoL) following diagnosis and treatment, particularly in those with incidental, actively monitored tumours. METHODS: A single-center, cross-sectional study was completed. Adult patients with surgically managed or actively monitored meningioma with more than five years of follow-up were included. The patient-reported outcome measures RAND SF-36, EORTC QLQ-C30 and QLQ-BN20 were used to evaluate HRQoL. HRQoL scores were compared to normative population data. Outcome determinants were evaluated using multivariate linear regression analysis. RESULTS: 243 patient responses were analyzed, and the mean time from diagnosis was 9.8 years (range 5.0-40.3 years). Clinically relevant, statistically significant HRQoL impairments were identified across several SF-36 and QLQ-C30 domains. Increasing education level (ß = 2.9, 95% CI 0.9 to 4.9), P = .004), employment (ß = 7.7, 95% CI 2.2 to 13.1, P = .006) and absence of postoperative complications (ß=-6.7, 95% CI -13.2 to (-)0.3, P = .041) were associated with a better QLQ-C30 summary score. Other tumour and treatment variables were not. CONCLUSION: This study highlights the longer-term disease burden of patients with meningioma nearly one decade after diagnosis or surgery. Patients with actively monitored meningioma have similar HRQoL to operated meningioma patients. Healthcare professionals should be mindful of HRQoL impairments and direct patients to sources of support as needed.


Assuntos
Neoplasias Meníngeas , Meningioma , Adulto , Humanos , Qualidade de Vida , Estudos Transversais , Meningioma/cirurgia , Neoplasias Meníngeas/cirurgia , Estudos de Coortes , Inquéritos e Questionários
3.
Palliat Support Care ; 21(5): 812-819, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35975283

RESUMO

OBJECTIVE: Caregivers of patients with primary brain tumor (PBT) describe feeling preoccupied with the inevitability of their loved one's death. However, there are currently no validated instruments to assess death anxiety in caregivers. This study sought to examine (1) the psychometric properties of the Death and Dying Distress Scale (DADDS), adapted for caregivers (DADDS-CG), and (2) the prevalence and correlates of death anxiety in caregivers of patients with PBT. METHODS: Caregivers (N = 67) of patients with PBT completed the DADDS-CG, Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder (GAD-7), Fear of Cancer Recurrence (FCR-7), and God Locus of Health Control (GLHC). Caregivers' sociodemographic information and patients' medical characteristics were also collected. Preliminary examination of the psychometric properties of the DADDS-CG was conducted using exploratory factor analysis, Cronbach's alpha, and correlations. The prevalence and risk factors of death anxiety were assessed using frequencies, pair-wise comparisons, and correlations. RESULTS: Factor analysis of the DADDS-CG revealed a two-factor structure consistent with the original DADDS. The DADDS-CG demonstrated excellent internal consistency, convergent validity with the PHQ-9, GAD-7, and FCR-7, and discriminant validity with the GLHC. Over two-thirds of caregivers reported moderate-to-severe symptoms of death anxiety. Death anxiety was highest in women and caregivers of patients with high-grade PBT. SIGNIFICANCE OF RESULTS: The DADDS-CG demonstrates sound psychometric properties in caregivers of patients with PBT, who report high levels of death anxiety. Further research is needed to support the measure's value in clinical care and research - both in this population and other caregivers - in order to address this unmet, psychosocial need.


Assuntos
Neoplasias Encefálicas , Cuidadores , Humanos , Feminino , Acedapsona , Transtornos de Ansiedade/diagnóstico , Psicometria , Ansiedade/etiologia , Ansiedade/diagnóstico , Neoplasias Encefálicas/complicações , Reprodutibilidade dos Testes , Inquéritos e Questionários
4.
Crit Rev Food Sci Nutr ; 62(30): 8335-8354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34014143

RESUMO

Hesperidin in orange juice may affect chronic disease biomarkers. This narrative systematic review aimed to determine appropriate recommendations toward the dose and frequency of hesperidin consumption from 100% orange juice and conduct a gap analysis. The Preferred Reporting Items for Systematic Review and Meta-analysis was conducted to identify articles through September 2020, utilizing four databases: Pub-Med Central, Agricola, Embase, and MEDLINE. Twenty articles met the inclusion criteria. Results showed that overall effect sizes from the studies were considerably weak. Although higher frequencies, doses, and concentration of hesperidin in 100% orange juice had an impact on global cognitive function, cardiac, insulin, inflammatory, antioxidant/phenolic, and oxidative stress outcomes compared to lower frequencies, doses, and concentration of hesperidin. A gap analysis demonstrated there was a variability in dose and frequency of OJ and hesperidin, diet, genetics, and evaluation measures, which made the role of hesperidin in 100% OJ on chronic diseases unclear. This review revealed a trend toward improving chronic disease biomarkers following consumption of hesperidin in 100% orange juice. Steps can be taken in future research to improve the consistency of clinical study designs, methodology and outcomes.


Assuntos
Citrus sinensis , Hesperidina , Humanos , Biomarcadores , Doença Crônica , Sucos de Frutas e Vegetais/análise
5.
J Neurooncol ; 155(1): 25-34, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34491526

RESUMO

BACKGROUND: CogMed Working Memory Training (CWMT) is a computer-based program shown to improve working memory (WM) among those with cognitive impairments. No study to date has investigated its feasibility, acceptability, and satisfaction in adult patients with glioma, despite the well-documented incidence of WM impairment in this population. METHODS: Twenty patients with glioma and objective and/or perceived WM deficits enrolled in the study: 52% high-grade, 60% female, Mage = 47 (range = 21-72 years). Adverse events were monitored to determine safety. Feasibility and acceptability were assessed based on established metrics. Satisfaction was explored by exit-interviews. Neurocognitive tests and psychological symptoms were analyzed at baseline and post-CWMT to estimate effect sizes. RESULTS: Of 20 enrolled patients, 16 completed the intervention (80% retention rate). Reasons for withdrawal included time burden (n = 2); tumor-related fatigue (n = 1) or loss to follow-up (n = 1). No adverse events were determined to be study-related. Adherence was 69% with reasons for nonadherence similar to those for study withdrawal. The perceived degree of benefit was only moderate. Baseline to post-CWMT assessments showed medium to large effects on neurocognitive tasks. Psychological symptoms remained stable throughout the study period. CONCLUSIONS: CWMT was found to be safe and acceptable in adult patients with glioma. Enrollment, retention rates, and treatment adherence were all adequate and comparable to studies recruiting similar populations. Only moderate perceived benefit was reported despite demonstrated improvements in objectively-assessed WM. This may indicate that the time commitment and intervention intensity (5 weeks of 50-min training sessions on 5 days/week) outweighed the perceived benefits of the program. (Trial Registration Number: NCT03323450 registered on 10/27/2017).


Assuntos
Disfunção Cognitiva , Glioma , Adulto , Idoso , Feminino , Glioma/complicações , Glioma/terapia , Humanos , Aprendizagem , Masculino , Transtornos da Memória/etiologia , Memória de Curto Prazo , Pessoa de Meia-Idade , Adulto Jovem
6.
Psychooncology ; 30(7): 1120-1128, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33599334

RESUMO

OBJECTIVE: Fear of cancer recurrence (FCR) is related to psychological distress and poor quality of life in cancer patients and their caregivers. However, no studies have investigated FCR in neuro-oncology. Given the varied prognosis, treatment, and disease trajectory of brain cancer, FCR may affect patients and their caregivers differently. METHODS: Eighty adult primary brain tumor (PBT) patients and 52 caregivers completed questionnaires assessing FCR and psychological distress (depressive symptoms, generalized anxiety, and death anxiety). Differences in patient and caregiver FCR by demographic and medical characteristics were examined. Using multilevel modeling, the Actor-Partner Interdependence Model (APIM) was used to investigate the interrelationship between patient and caregiver FCR with demographics and psychological distress measures. RESULTS: Caregivers reported significantly higher FCR than patients. There were no effects of demographic or medical characteristics on patient FCR. Time since diagnosis was negatively related to caregiver FCR. All measures of psychological distress exerted a significant actor effect on FCR among both patients and caregivers. Two partner effects were found: caregiver depressive symptoms and death anxiety negatively predicted patients' FCR. CONCLUSIONS: This is the first investigation of FCR in PBT patients and their caregivers. Most demographic and medical characteristics were not related to patient or caregiver FCR. Caregiver FCR may be higher at the time of diagnosis and decrease over time. APIMs revealed actor effects on patient and caregiver FCR for all measures of psychological distress. Results demonstrated the dyadic effects of a brain tumor diagnosis, emphasizing the need to include caregivers in psychotherapy for neuro-oncology patients.


Assuntos
Neoplasias Encefálicas , Cuidadores , Adulto , Ansiedade , Neoplasias Encefálicas/terapia , Depressão , Medo , Humanos , Recidiva Local de Neoplasia , Qualidade de Vida
7.
Brain Inj ; 35(14): 1665-1673, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34874214

RESUMO

OBJECTIVE: We assessed agreement between patient- and informant-report on the Behavior Rating Inventory of Executive Function - Adult (BRIEF-A) in patients with primary brain tumors (PBT) and differences on BRIEF-A in neurocognitive (intact v. impaired), psychological (asymptomatic v. distressed), and functional (independent v. dependent) categories using both patient- and informant-report. METHOD: PBT patients (n = 102) completed neuropsychological evaluations including the BRIEF-A, clinical interview, neurocognitive tests, and mood questionnaires. Correlations between the BRIEF-A and Informant (n = 39) were conducted. Differences in patient and informant BRIEF-A indices were investigated across five classifications: neurocognitive functioning, psychological functioning, medication management, appointment management, and finance management. RESULTS: Patient and informant BRIEF were correlated. There was no difference on BRIEF-A or Informant indices for intact v. impaired neurocognitive status. Higher BRIEF-A and Informant indices were observed among psychologically distressed v. asymptomatic patients. Results showed higher BRIEF indices among those requiring assistance with medication, appointments, and finances. CONCLUSIONS: Patients and informants agreed in their reports of executive function (EF). These reports, while not different in neurocognitive classification, were different in psychological functioning and in those needing assistance with instrumental activities of daily living (IADL). Patient- and informant-reported EF may provide important data regarding psychological and IADL functioning in this population.


Assuntos
Neoplasias Encefálicas , Disfunção Cognitiva , Atividades Cotidianas/psicologia , Adulto , Neoplasias Encefálicas/complicações , Função Executiva , Humanos , Testes Neuropsicológicos
8.
Int J Mol Sci ; 22(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204158

RESUMO

Breast cancer (BC) is the most predominant type of cancer among women. The aim of this study is to find new biomarkers that can help in early detection of BC, especially for those who are too young to be screened using mammography as per guidelines. Using microRNA microarray, we previously showed dysregulation of 74 microRNAs in tumors from early BC patients as compared with normal adjacent tissues, which we were interested in studying in blood circulation. In this study, we investigated the expression of 12 microRNA (miR-21/miR-155/miR-23a/miR-130a/miR-145/miR-425-5p/miR-139-5p/miR-451/miR-195/miR-125b/miR-100, and miR-182) in the plasma of 41 newly diagnosed Lebanese BC patients with early invasive ductal carcinoma as compared with 32 healthy controls. Total RNA was extracted from plasma, and expression levels of miRNA of interest were measured using RT-qPCR followed by statistical analysis; miR-21, miR-155, miR-23a, miR-130a, miR-145, miR-425-5p, and miR-139-5p were significantly upregulated and miR-451 was significantly downregulated, in the plasma of BC patients as compared with healthy controls. The positively correlated miR-23a, miR-21, and miR-130a had a high diagnostic accuracy (86%). Importantly, the combination of miR-145/miR-425-5p/miR-139-5p/miR-130a scored the highest diagnostic accuracy of 95% with AUC = 0.97 (sensitivity 97% and specificity 91%). MicroRNAs are promising non-invasive diagnostic biomarkers for early-stage BC with the panel of miR-145/miR-425-5p/miR-139-5p/miR-130a having the highest diagnostic accuracy.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , MicroRNA Circulante/sangue , MicroRNA Circulante/genética , Perfilação da Expressão Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estatísticas não Paramétricas , Adulto Jovem
9.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361729

RESUMO

Tyrosinase (TYR) is a type III copper oxidase present in fungi, plants and animals. The inhibitor of human TYR plays a vital role in pharmaceutical and cosmetic fields by preventing synthesis of melanin in the skin. To search for an effective TYR inhibitor from various plant extracts, a kinetic study of TYR inhibition was performed with mushroom TYR. Among Panax ginseng, Alpinia galanga, Vitis vinifera and Moringa oleifera, the extracts of V. vinifera seed, A. galanga rhizome and M. oleifera leaf reversibly inhibited TYR diphenolase activity with IC50 values of 94.8 ± 0.2 µg/mL, 105.4 ± 0.2 µg/mL and 121.3 ± 0.4 µg/mL, respectively. Under the same conditions, the IC50 values of the representative TYR inhibitors of ascorbic acid and kojic acid were found at 235.7 ± 1.0 and 192.3 ± 0.4 µg/mL, respectively. An inhibition kinetics study demonstrated mixed-type inhibition of TYR diphenolase by A. galanga and V. vinifera, whereas a rare uncompetitive inhibition pattern was found from M. oleifera with an inhibition constant of Kii 73 µg/mL. Phytochemical investigation by HPLC-MS proposed luteolin as a specific TYR diphenolase ES complex inhibitor, which was confirmed by the inhibition kinetics of luteolin. The results clearly showed that studying TYR inhibition kinetics with plant extract mixtures can be utilized for the screening of specific TYR inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Luteolina/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Moringa oleifera/química , Agaricales/química , Agaricales/enzimologia , Alpinia/química , Ácido Ascórbico/química , Ácido Ascórbico/isolamento & purificação , Ácido Ascórbico/farmacologia , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Proteínas Fúngicas/isolamento & purificação , Ensaios de Triagem em Larga Escala , Concentração Inibidora 50 , Cinética , Luteolina/química , Luteolina/isolamento & purificação , Monofenol Mono-Oxigenase/isolamento & purificação , Panax/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Pironas/química , Pironas/isolamento & purificação , Pironas/farmacologia , Rizoma/química , Sementes/química , Vitis/química
10.
J Clin Psychol Med Settings ; 28(1): 16-30, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31848927

RESUMO

Primary brain tumor (PBT) patients may experience existential distress; however, few studies have examined this issue. The objectives of this study were to (1) systematically review PBT representation in psycho-oncology literature regarding fear/anxiety related to progression, recurrence, and death and (2) preliminarily assess the prevalence of fear of dying in a sample of PBT patients. Systematic searching of three databases yielded 1555 articles for review. Of these, 327 studies met inclusion criteria (patient sample N = 132,951). Only eight studies (0.18% of the participants) included patients with a PBT diagnosis, potentially due to exclusion criteria such as cognitive impairment or specific treatment parameters which may prohibit PBT patient participation. Review of the results from the eight included studies revealed mixed methods and limited demographic analyses; existential distress was correlated with heightened depression and anxiety, and overall worsened quality of life. From the original data collection, approximately one-third of PBT patients endorsed fear of dying, which was positively related to depression severity. Taken together, results suggest that PBT patients are considerably underrepresented in existential psycho-oncology literature, despite preliminary findings suggesting prevalence of these concerns. Future research on existential distress in neuro-oncology is warranted.


Assuntos
Neoplasias Encefálicas , Qualidade de Vida , Adulto , Ansiedade/epidemiologia , Medo , Humanos , Psico-Oncologia , Revisões Sistemáticas como Assunto
11.
Palliat Support Care ; 19(6): 672-680, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-36942577

RESUMO

OBJECTIVE: This study investigated death anxiety in patients with primary brain tumor (PBT). We examined the psychometric properties of two validated death anxiety measures and determined the prevalence and possible determinants of death anxiety in this often-overlooked population. METHODS: Two cross-sectional studies in neuro-oncology were conducted. In Study 1, 81 patients with PBT completed psychological questionnaires, including the Templer Death Anxiety Scale (DAS). In Study 2, 109 patients with PBT completed similar questionnaires, including the Death and Dying Distress Scale (DADDS). Medical and disease-specific variables were collected across participants in both studies. Psychometric properties, including construct validity, internal consistency, and concurrent validity, were investigated. Levels of distress were analyzed using frequencies, and determinants of death anxiety were identified using logistic regression. RESULTS: The DADDS was more psychometrically sound than the DAS in patients with PBT. Overall, 66% of PBT patients endorsed at least one symptom of distress about death and dying, with 48% experiencing moderate-severe death anxiety. Generalized anxiety symptoms and the fear of recurrence significantly predicted death anxiety. SIGNIFICANCE OF RESULTS: The DADDS is a more appropriate instrument than the DAS to assess death anxiety in neuro-oncology. The proportion of patients with PBT who experience death anxiety appears to be higher than in other advanced cancer populations. Death anxiety is a highly distressing symptom, especially when coupled with generalized anxiety and fears of disease progression, which appears to be the case in patients with PBT. Our findings call for routine monitoring and the treatment of death anxiety in neuro-oncology.


Assuntos
Acedapsona , Neoplasias Encefálicas , Humanos , Prevalência , Estudos Transversais , Atitude Frente a Morte , Ansiedade/psicologia , Inquéritos e Questionários , Neoplasias Encefálicas/complicações
12.
Int J Mol Sci ; 19(9)2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30217071

RESUMO

Given the safety and potential benefits of intravenous ascorbic acid (AA) administration in cancer patients, there is merit in further exploring this therapeutic concept. In this review, we discuss the potential benefits of intravenous AA administration on colorectal cancer and we specifically focus on its effect on glycolysis in mutant and wild type RAS. We perform a PubMed and Ovid MEDLINE search using ascorbic acid, intravenous vitamin C, KRAS mutation, BRAF mutation and colorectal cancer (CRC) as keywords. At the cellular level, colorectal cancer cells undergo a metabolic shift called the Warburg effect to allow for more glucose absorption and utilization of glycolysis. This shift also allows AA to enter which leads to a disruption in the Warburg effect and a shutdown of the downstream KRAS pathway in mutated KRAS colon cancer cells. At the clinical level, AA is associated with tumour regression in advanced disease and improved tolerability and side effects of standard therapy. Based on these findings, we conclude that further clinical trials are needed on a larger scale to examine the therapeutic benefits of AA in colon cancer.


Assuntos
Ácido Ascórbico/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Humanos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos
14.
Dysphagia ; 31(6): 765-770, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27503565

RESUMO

The six-food elimination diet (SFED), where dairy, wheat, eggs, soy, nuts, and seafood are avoided, is an effective treatment for eosinophilic esophagitis (EoE). Patient-related costs of this approach, however, are unknown. We aimed to assess the cost of and ease of shopping for an SFED compared to an unrestricted diet. A dietitian with expertise in EoE generated menus meeting dietary requirements for a week's worth of meals for the SFED and an unrestricted diet. We compared prices and the number of missing items for both diets at standard and specialty grocery stores. The average weekly price of the SFED at a standard supermarket was $92.54 compared to $79.84 for an unrestricted diet (p = 0.0001). A patient shopping at a standard grocery store needed a higher proportion of items from a second store compared to an unrestricted diet (32 vs. 3 %, p = 0.0001). The prices of the SFED and unrestricted diet using a specialty supermarket were comparable ($106.47 vs. $105.96, p = 0.81), as was the percentage of items requiring a trip to a second store (6 vs. 2 % items, p = 0.03). Shopping at a specialty grocery store increased weekly grocery costs by $13.93 (p = 0.04) for the SFED and $26.12 (p = 0.03) for the unrestricted diet. In conclusion, for patients shopping at standard grocery stores, the cost of an SFED is higher, and an SFED requires more items from a second store. These differences disappear at specialty grocery stores, but costs were significantly higher. This cost and logistical burden can inform patients when selecting dietary therapy.


Assuntos
Dieta/economia , Esofagite Eosinofílica/dietoterapia , Alimentos/economia , Comércio , Custos e Análise de Custo/estatística & dados numéricos , Dieta/métodos , Esofagite Eosinofílica/economia , Humanos , Estados Unidos
15.
J Radiol Prot ; 36(4): 736-745, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27631559

RESUMO

The first validation results of the two approaches developed in the ELDO project for retrospective assessment of eye lens doses for interventional cardiologists (ICs) are presented in this paper. The first approach (a) is based on both the readings from the routine whole body dosimeter worn above the lead apron and procedure-dependent conversion coefficients, while the second approach (b) is based on detailed information related to the occupational exposure history of the ICs declared in a questionnaire and eye lens dose records obtained from the relevant literature. The latter approach makes use of various published eye lens doses per procedure as well as the appropriate correction factors which account for the use of radiation protective tools designed to protect the eye lens. To validate both methodologies, comprehensive measurements were performed in several Polish clinics among recruited physicians. Two dosimeters measuring whole body and eye lens doses were worn by every physician for at least two months. The estimated cumulative eye lens doses, calculated from both approaches, were then compared against the measured eye lens dose value for every physician separately. Both approaches results in comparable estimates of eye lens doses and tend to overestimate rather than underestimate the eye lens doses. The measured and estimated doses do not differ, on average, by a factor higher than 2.0 in 85% and 62% of the cases used to validate approach (a) and (b), respectively. In specific cases, however, the estimated doses differ from the measured ones by as much as a factor of 2.7 and 5.1 for method (a) and (b), respectively. As such, the two approaches can be considered accurate when retrospectively estimating the eye lens doses for ICs and will be of great benefit for ongoing epidemiological studies.


Assuntos
Cardiologistas , Cristalino/efeitos da radiação , Exposição Ocupacional/análise , Doses de Radiação , Radiologia Intervencionista , Adulto , Dispositivos de Proteção dos Olhos , Feminino , Humanos , Masculino , Polônia , Roupa de Proteção , Proteção Radiológica/métodos , Radiometria/métodos , Inquéritos e Questionários
16.
J Med Liban ; 64(2): 116-122, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-30452151

RESUMO

A large family of small 18-25 nucleotide long non coding RNA molecules now known as microRNA (miRNA) was described two decades ago, and has been recently es- tablished as post-transcriptional gene regulators. miRNAs were shown to be involved in the regulation of diverse phys- iological and developmental processes. Moreover, dysregula- tion of specific miRNAs has been implicated later in several pathologies including cancer. Owing to their presence and stability in body fluids, miRNAs have been investigated as novel circulating non-invasive biomarkers. Accordingly, their role as potential diagnostic, prognostic or predictive biomark- ers for many cancer types has recently emerged. This review tackles the use of circulating miRNAs in cancer detection, diagnosis and prognosis, giving examples using common solid tumors and discussing the advantages of their use, the challenges facing this novel circulating biomarker and recorn- mendatidns to overcome them.


Assuntos
MicroRNA Circulante/análise , Neoplasias/diagnóstico , Neoplasias/genética , Biomarcadores Tumorais/análise , Humanos , Prognóstico
18.
Zygote ; 22(3): 378-86, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23237064

RESUMO

Cryopreservation is a technique used to preserve cells for long-time storage. It is widely used in agriculture to store male gametes in liquid nitrogen. The aim of this study was to determine the optimum thawing temperature and time for samples subjected to annexin V magnetic-activated cell sorting (AnMACS) as the sperm preparation technique. Pooled semen samples from three ejaculates were divided into two groups. The treatment group was subjected both to AnMACS and to being cryopreserved, whilst the control group was cryopreserved directly without MACS. Post-thaw analysis was carried out for samples thawed at either 20°C for 13 s, 37°C for 30 s, 40°C for 7 s, 60°C for 6 s or 80°C for 5 s. Sperm kinematics, viability and capacitation status were determined for samples subjected to all thawing temperatures described. Results showed that thawing at 37°C for 13 s for MACS-processed samples was a superior option compared with other thawing procedures; there was a significant difference in P < 0.05 values for curvilinear velocity (VCL µm/s) and sperm straightness (STR %) when samples were thawed at 40°C for 7 s, with fewer capacitated spermatozoa (P < 0.05) when samples were thawed at 37°C for 30 s, 40°C for 7 s or 60°C for 6 s. Hence, we can speculate that the use of AnMACS as the sperm preparation technique can somehow enhance sperm cryosurvival rate after cryopreservation, however the fertilization potential of these cells has yet to be determined.


Assuntos
Criopreservação/métodos , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Animais , Bovinos , Sobrevivência Celular , Fenômenos Magnéticos , Masculino , Preservação do Sêmen/métodos , Capacitação Espermática , Temperatura
19.
J Radiol Prot ; 34(3): 509-28, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24938591

RESUMO

Monte Carlo calculations were used to investigate the efficiency of radiation protection equipment in reducing eye and whole body doses during fluoroscopically guided interventional procedures. Eye lens doses were determined considering different models of eyewear with various shapes, sizes and lead thickness. The origin of scattered radiation reaching the eyes was also assessed to explain the variation in the protection efficiency of the different eyewear models with exposure conditions. The work also investigates the variation of eye and whole body doses with ceiling-suspended shields of various shapes and positioning. For all simulations, a broad spectrum of configurations typical for most interventional procedures was considered. Calculations showed that 'wrap around' glasses are the most efficient eyewear models reducing, on average, the dose by 74% and 21% for the left and right eyes respectively. The air gap between the glasses and the eyes was found to be the primary source of scattered radiation reaching the eyes. The ceiling-suspended screens were more efficient when positioned close to the patient's skin and to the x-ray field. With the use of such shields, the Hp(10) values recorded at the collar, chest and waist level and the Hp(3) values for both eyes were reduced on average by 47%, 37%, 20% and 56% respectively. Finally, simulations proved that beam quality and lead thickness have little influence on eye dose while beam projection, the position and head orientation of the operator as well as the distance between the image detector and the patient are key parameters affecting eye and whole body doses.


Assuntos
Imagens de Fantasmas , Proteção Radiológica/instrumentação , Radiologia Intervencionista , Dispositivos de Proteção dos Olhos , Cristalino , Método de Monte Carlo , Radiometria , Contagem Corporal Total
20.
J Radiol Prot ; 34(2): 279-96, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24704989

RESUMO

This paper's goal is to assess secondary neutron doses received by paediatric patients treated for intracranial tumours using a 178 MeV proton beam. The MCNPX Monte Carlo model of the proton therapy facility, previously validated through experimental measurements for both proton and neutron dosimetry, was used. First, absorbed dose was calculated for organs located outside the clinical target volume using a series of hybrid computational phantoms for different ages and considering a realistic treatment plan. In general, secondary neutron dose was found to decrease as the distance to the treatment field increases and as the patient age increases. In addition, secondary neutron doses were studied as a function of the beam incidence. Next, neutron equivalent dose was assessed using organ-specific energy-dependent radiation weighting factors determined from Monte Carlo simulations of neutron spectra at each organ. The equivalent dose was found to reach a maximum value of ∼155 mSv at the level of the breasts for a delivery of 49 proton Gy to an intracranial tumour of a one-year-old female patient. Finally, a thorough comparison of the calculation results with published data demonstrated the dependence of neutron dose on the treatment configuration and proved the need for facility-specific and treatment-dependent neutron dose calculations.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/radioterapia , Transferência Linear de Energia , Modelos Biológicos , Nêutrons , Terapia com Prótons/métodos , Contagem Corporal Total/métodos , Absorção de Radiação , Adolescente , Adulto , Criança , Pré-Escolar , Simulação por Computador , Feminino , Humanos , Lactente , Masculino , Especificidade de Órgãos , Doses de Radiação , Dosagem Radioterapêutica , Espalhamento de Radiação , Adulto Jovem
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