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4.
J Urol ; : 101097JU0000000000003965, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38603578

RESUMEN

PURPOSE: Second malignancy is a rare but potentially lethal event after prostate brachytherapy, but data remain scarce on its long-term risk. The objective of this study is to estimate the number of pelvic second malignancies following brachytherapy compared to radical prostatectomy (RP). MATERIALS AND METHODS: We retrospectively reviewed patients treated with low-dose 125I brachytherapy and RP in British Columbia from 1999 to 2010. Kaplan-Meier estimates for pelvic (bladder and rectum), invasive pelvic, any second malignancy, and death from any second malignancy were assessed. Cox multivariable analyses were performed adjusting for initial treatment type, age, post-RP adjuvant/salvage external beam radiation therapy status, and smoking history. RESULTS: Two thousand three hundred seventy-eight brachytherapy and 9089 RP patients were included. Median age was 66 years (interquartile range [IQR] 61-71) and 63 years (IQR 58-67), respectively. Median follow-up time to event or censured was 14 years (IQR 11.5-17.3). The Kaplan-Meier estimates for pelvic second malignancy at 15 and 20 years were 6.4% and 9.8%, respectively, after brachytherapy, and 3.2% and 4.2% after RP. Time to any second malignancy and time to death from any second malignancy were not significantly different (P > .05). On Cox multivariable analysis, brachytherapy, compared to surgery, was an independent factor for pelvic (hazard ratio [HR] 1.81 [95% CI 1.45-2.26], P < .001) and invasive pelvic second malignancy (HR 2.13 [95% CI 1.61-2.83], P < .001). Increased age and smoking were also associated with higher estimates of events (P < .001). CONCLUSIONS: After adjustment for age, post-RP adjuvant/salvage external beam radiation therapy status, and smoking status, numerically higher long-term HRs of pelvic and invasive pelvic second malignancy in patients treated with brachytherapy compared to RP were noted.

6.
Neuroimage ; 283: 120395, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37832707

RESUMEN

Brain decoding aims to infer cognitive states from patterns of brain activity. Substantial inter-individual variations in functional brain organization challenge accurate decoding performed at the group level. In this paper, we tested whether accurate brain decoding models can be trained entirely at the individual level. We trained several classifiers on a dense individual functional magnetic resonance imaging (fMRI) dataset for which six participants completed the entire Human Connectome Project (HCP) task battery >13 times over ten separate fMRI sessions. We evaluated nine decoding methods, from Support Vector Machines (SVM) and Multi-Layer Perceptron (MLP) to Graph Convolutional Neural Networks (GCN). All decoders were trained to classify single fMRI volumes into 21 experimental conditions simultaneously, using ∼7 h of fMRI data per participant. The best prediction accuracies were achieved with GCN and MLP models, whose performance (57-67 % accuracy) approached state-of-the-art accuracy (76 %) with models trained at the group level on >1 K hours of data from the original HCP sample. Our SVM model also performed very well (54-62 % accuracy). Feature importance maps derived from MLP -our best-performing model- revealed informative features in regions relevant to particular cognitive domains, notably in the motor cortex. We also observed that inter-subject classification achieved substantially lower accuracy than subject-specific models, indicating that our decoders learned individual-specific features. This work demonstrates that densely-sampled neuroimaging datasets can be used to train accurate brain decoding models at the individual level. We expect this work to become a useful benchmark for techniques that improve model generalization across multiple subjects and acquisition conditions.


Asunto(s)
Conectoma , Humanos , Conectoma/métodos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Redes Neurales de la Computación , Aprendizaje
7.
Eur Urol Focus ; 2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37872081

RESUMEN

Tissue engineering, once promising, faces significant technical challenges. Current limitations impede progression of the field, as evidenced by clinical trial failures over the past decades. Existing established surgical techniques remain the only proven, successful, and durable methods for bladder reconstruction.

8.
World J Urol ; 41(10): 2637-2646, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37524850

RESUMEN

PURPOSE: Electronic cigarette (e-cig) use is prevalent. The health implications of e-cig use on the genitourinary (GU) system are uncertain. This systematic review aims to evaluate how e-cig use impacts the GU system. METHODS: A systematic search was conducted in PubMed, Embase and Ovid alongside citation searching. Review articles, non-English papers, animal model/cell line studies or articles only on combustible cigarettes were excluded. Quality assessment was undertaken using the Joanna Briggs Institute checklists. The primary endpoint was the impact of e-cig use on bladder cancer incidence. Secondary outcomes included urinary carcinogens, chronic kidney disease (CKD), reproductive disorders, and other GU diseases. RESULTS: The search yielded 244 articles, 28 were ultimately included. One study assessed risk of bladder cancer and found the use of e-cig was associated with an increased odds ratio of 1.577 for its diagnosis. Twenty-one articles measured potential urinary carcinogens-including crotonaldehyde and benzene-associated with bladder cancer. Two articles evaluated the association of e-cig use with CKD and reported mixed outcomes. Three articles reported on reproductive disorders, specifically, stuttering priapism and changes to sperm quantity and quality. One study reported on other GU diseases, specifically burns to the GU system. After quality assessment, all articles were deemed to be of acceptable quality for inclusion. CONCLUSIONS: E-cig use was associated with an increased risk of bladder cancer, increased exposure to carcinogenic compounds, mixed evidence on CKD, increased risk of reproductive disorders and burns to the GU system. Further studies are needed to understand long-term GU effects.


Asunto(s)
Quemaduras , Sistemas Electrónicos de Liberación de Nicotina , Insuficiencia Renal Crónica , Neoplasias de la Vejiga Urinaria , Vapeo , Masculino , Animales , Vapeo/efectos adversos , Semen , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/etiología , Carcinógenos , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/etiología
12.
Neuroimage ; 255: 119205, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35427774

RESUMEN

Mnemonic representations vary in fidelity, sharpness, and strength-qualities that can be examined using both introspective judgements of mental states and objective measures of brain activity. Subjective and objective measures are both valid ways of "reading out" the content of someone's internal mnemonic states, each with different strengths and weaknesses. St-Laurent and colleagues (2015) compared the neural correlates of memory vividness ratings with patterns of neural reactivation evoked during memory recall and found considerable overlap between the two, suggesting a common neural basis underlying these different markers of representational quality. Here we extended this work with meta-analytic methods by pooling together four neuroimaging datasets in order to contrast the neural substrates of neural reactivation and those of vividness judgements. While reactivation and vividness judgements correlated positively with one another and were associated with common univariate activity in the dorsal attention network and anterior hippocampus, some notable differences were also observed. Vividness judgments were tied to stronger activation in the striatum and dorsal attention network, together with activity suppression in default mode network nodes. We also observed a trend for reactivation to be more closely associated with early visual cortex activity. A mediation analysis found support for the hypothesis that neural reactivation is necessary for memory vividness, with activity in the anterior hippocampus associated with greater reactivation. Our results suggest that neural reactivation and vividness judgements reflect common mnemonic processes but differ in the extent to which they engage effortful, attentional processes. Additionally, the similarity between reactivation and vividness appears to arise, partly, through hippocampal engagement during memory retrieval.


Asunto(s)
Juicio , Memoria Episódica , Mapeo Encefálico/métodos , Hipocampo/fisiología , Humanos , Imagen por Resonancia Magnética , Memoria/fisiología , Recuerdo Mental/fisiología
13.
Can Urol Assoc J ; 14(8): 245-251, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32213276

RESUMEN

INTRODUCTION: Our aim was to explore the satisfaction, personal and professional challenges, and practice barriers among female urologists in Canada. METHODS: A literature review was completed to design our survey. Trends with respect to career and personal satisfaction were identified, including academic advancement, mentorship, professional challenges, workplace discrimination, family satisfaction, and remuneration, among others. These key themes were formatted into 44 questions, translated into French, and distributed electronically as a survey to 80 female urology staff across Canada. RESULTS: Sixty (75.0%) women completed the survey. Many had been in practice <5 years (44.1%) and 72.9% completed a fellowship. Overall, 96.6% of women were very or somewhat satisfied with their career. Seeing more time-consuming patients and financial constraints within the healthcare system were the greatest source of dissatisfaction. Two-thirds of respondents reported that they received significant mentorship and 40% found it difficult to find a mentor during their training. Overall, 65.0% experienced gender discrimination, most commonly from a colleague or a patient. Women who practiced in the community were more likely to report experiencing discrimination compared to women practicing in an academic setting (78.1% vs. 51.9%; p=0.034). Mean time for maternity leave was 17.1 (±8.3) weeks, and 30.2% reported a pregnancy-related complication triggered by their work. Overall, 66.1% would choose urology again. CONCLUSIONS: It is important to advocate for the wellness of female urologists. To accomplish this, we need to address the challenges revealed in the survey, including supporting women on maternity leave, improving mentorship, and prioritizing female urology leadership initiatives. We have established a formal circle of support within the urology community in Canada to achieve these goals.

14.
Neuropsychologia ; 142: 107436, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32194085

RESUMEN

As clear memories transport us back into the past, the brain also revives prior patterns of neural activity, a phenomenon known as neural reactivation. While growing evidence indicates a link between neural reactivation and typical variations in memory performance in healthy individuals, it is unclear how and to what extent reactivation is disrupted by a memory disorder. The current study characterizes neural reactivation in a case of amnesia using Multivoxel Pattern Analysis (MVPA). We tested NC, an individual with developmental amnesia linked to a diencephalic stroke, and 19 young adult controls on a functional magnetic resonance imaging (fMRI) task during which participants viewed and recalled short videos multiple times. An encoding classifier trained and tested to identify videos based on brain activity patterns elicited at perception revealed superior classification in NC. The enhanced consistency in stimulus representation we observed in NC at encoding was accompanied by an absence of multivariate repetition suppression, which occurred over repeated viewing in the controls. Another recall classifier trained and tested to identify videos during mental replay indicated normal levels of classification in NC, despite his poor memory for stimulus content. However, a cross-condition classifier trained on perception trials and tested on mental replay trials-a strict test of reactivation-revealed significantly poorer classification in NC. Thus, while NC's brain activity was consistent and stimulus-specific during mental replay, this specificity did not reflect the reactivation of patterns elicited at perception to the same extent as controls. Fittingly, we identified brain regions for which activity supported stimulus representation during mental replay to a greater extent in NC than in controls. This activity was not modeled on perception, suggesting that compensatory patterns of representation based on generic knowledge can support consistent mental constructs when memory is faulty. Our results reveal several ways in which amnesia impacts distributed patterns of stimulus representation during encoding and retrieval.


Asunto(s)
Mapeo Encefálico , Recuerdo Mental , Amnesia/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Memoria , Adulto Joven
15.
Cardiovasc Diagn Ther ; 9(4): 319-327, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31555536

RESUMEN

BACKGROUND: Integrating biomedical sensors to a telerehabilitation platform allowed clinicians to receive real-time transmissions of the electrocardiogram (ECG) signal, oxygen saturation, and heart rate during an exercise program. These clinical data could be helpful to adjust and personalize the intensity of exercises to each patient's condition. The purpose of this study was to evaluate the feasibility and usefulness of biomedical sensors in telerehabilitation in patients with heart failure (HF). METHODS: Four participants with HF (mean age 66 years) followed the 12-week cardiac program using telerehabilitation, including sensors to monitor real-time vital signs during sessions. The exercise program included cardiovascular, strengthening and flexibility exercises. Participants were evaluated before the intervention and one month after the end of the program. Functional capacity was measured with Cardiopulmonary Exercise Testing (CPX), the 6-minute walk test (6MWT), and the sit to stand test (STST). Quality of life was objectified using the Kansas City Cardiomyopathy Questionnaire (KCCQ). RESULTS: Our main objective demonstrated that real-time biomedical sensors can be safely used by clinicians during a telerehabilitation session. Most participants showed a tendency to improve their physical capacities such as walking distance and lower limb muscular strength. As a main outcome of cardiac rehabilitation (CR), quality of life seems to improve after the 12-week intervention. CONCLUSIONS: This study proved the feasibility of using telerehabilitation with real-time biomedical sensors as an alternative or a complement to the conventional CR program. Use of sensors allowed a safe environment for the patient and an adequate and personalized exercise prescription. Limitation in one-to-one supervision must be challenged in future clinical trials to demonstrate that telerehabilitation could be efficient for cardiac patients requiring more individual supervision than group sessions in a gymnasium.

16.
Can Urol Assoc J ; 13(8): 246-249, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31496490

RESUMEN

INTRODUCTION: Radiation exposure during urological procedures is still of concern in the urology community. It has been reported that percutaneous nephrolithotomy (PCNL) in supine position has less irradiation, as the puncture is mostly done under ultrasound guidance. However, it can also be done under fluoroscopy guidance. Unfortunately, data on radiation exposure during PCNL is lacking since they are often drawn from generalization and extrapolation, or they do not evaluate new procedures or different positions. The aim of our study was to compare the radiation dose depending on the position of the surgeon during PCNL. METHODS: A portable C-arm was used in standard mode (32 impulsions/second; 98 kV, 3.8 mA). Specific dosimeters were placed for lens, extremity, and torso. Anthropomorphic models and hand phantom models were used to reproduce the position of surgeon and patient (with same bone density as human) during PCNL in prone and modified supine position. Fluoroscopy time (FT) was six minutes to obtain higher exploitable signal, and the results are given for a FT of three minutes (more realistic). Ten percent of the FT is done with an angulation of 15 degrees and the rest in anteroposterior position. RESULTS: The equivalent doses (ED) are given in uSV (uncertainty k=2). During the modified supine position: neck, lens, right index finger, left thumb, and index finger received EDs of 99 (20%), 62 (18%), 437 (10%), 112 (12%), and 204 (10%), respectively. In a prone position, the phantom received ED on the neck, lens, right thumb and index finger, left thumb and index finger of 85 (20%), 92 (12%), 401 (10%), 585 (10%), 295 (10%), and 567 (10%), respectively. In both positions, the right hand seems more exposed than the left hand. CONCLUSIONS: The effective dose is 1.5- and 1.3-fold higher for lens and extremities, respectively, in prone position PCNL compared to modified supine position. Both positions are still well below the recommended limit for professional exposure.

17.
J Gerontol B Psychol Sci Soc Sci ; 74(7): 1086-1100, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31155678

RESUMEN

OBJECTIVES: Aging can reduce the specificity with which memory episodes are represented as distributed patterns of brain activity. It remains unclear, however, whether repeated encoding and retrieval of stimuli modulate this decline. Memory repetition is thought to promote semanticization, a transformative process during which episodic memory becomes gradually decontextualized and abstracted. Because semantic memory is considered more resilient to aging than context-rich episodic memory, we hypothesized that repeated retrieval would affect cortical reinstatement differently in young versus older adults. METHODS: We reanalyzed data from young and older adults undergoing functional magnetic resonance imaging while repeatedly viewing and recalling short videos. We derived trial-unique multivariate measures of similarity between video-specific brain activity patterns elicited at perception and at recall, which we compared between age groups at each repetition. RESULTS: With repetition, memory representation became gradually more distinct from perception in young adults, as reinstatement specificity converged downward toward levels observed in the older group. In older adults, alternative representations that were item-specific but orthogonal to patterns elicited at perception became more salient with repetition. DISCUSSION: Repetition transformed dominant patterns of memory representation away and orthogonally from perception in young and older adults, respectively. Although distinct, both changes are consistent with repetition-induced semanticization.


Asunto(s)
Envejecimiento/fisiología , Percepción Auditiva/fisiología , Mapeo Encefálico , Sustancia Gris/fisiología , Memoria Episódica , Recuerdo Mental/fisiología , Percepción Visual/fisiología , Adulto , Factores de Edad , Anciano , Señales (Psicología) , Femenino , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Semántica , Adulto Joven
18.
Cereb Cortex ; 29(3): 1075-1089, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29415220

RESUMEN

Half a century ago, Donald Hebb posited that mental imagery is a constructive process that emulates perception. Specifically, Hebb claimed that visual imagery results from the reactivation of neural activity associated with viewing images. He also argued that neural reactivation and imagery benefit from the re-enactment of eye movement patterns that first occurred at viewing (fixation reinstatement). To investigate these claims, we applied multivariate pattern analyses to functional MRI (fMRI) and eye tracking data collected while healthy human participants repeatedly viewed and visualized complex images. We observed that the specificity of neural reactivation correlated positively with vivid imagery and with memory for stimulus image details. Moreover, neural reactivation correlated positively with fixation reinstatement, meaning that image-specific eye movements accompanied image-specific patterns of brain activity during visualization. These findings support the conception of mental imagery as a simulation of perception, and provide evidence consistent with the supportive role of eye movement in neural reactivation.


Asunto(s)
Encéfalo/fisiología , Movimientos Oculares , Imaginación/fisiología , Percepción Visual/fisiología , Adolescente , Adulto , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria/fisiología , Análisis Multivariante , Estimulación Luminosa , Adulto Joven
19.
Hippocampus ; 28(10): 745-764, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29989271

RESUMEN

The dynamic process of memory consolidation involves a reorganization of brain regions that support a memory trace over time, but exactly how the network reorganizes as the memory changes remains unclear. We present novel converging evidence from studies of animals (rats) and humans for the time-dependent reorganization and transformation of different types of memory as measured both by behavior and brain activation. We find that context-specific memories in rats, and naturalistic episodic memories in humans, lose precision over time and activity in the hippocampus decreases. If, however, the retrieved memories retain contextual or perceptual detail, the hippocampus is engaged similarly at recent and remote timepoints. As the interval between the timepoint increases, the medial prefrontal cortex is engaged increasingly during memory retrieval, regardless of the context or the amount of retrieved detail. Moreover, these hippocampal-frontal shifts are accompanied by corresponding changes in a network of cortical structures mediating perceptually-detailed as well as less precise, schematic memories. These findings provide cross-species evidence for the crucial interplay between hippocampus and neocortex that reflects changes in memory representation over time and underlies systems consolidation.


Asunto(s)
Encéfalo/fisiología , Hipocampo/citología , Consolidación de la Memoria/fisiología , Memoria Episódica , Neuronas/fisiología , Adulto , Análisis de Varianza , Animales , Reacción de Prevención/fisiología , Encéfalo/diagnóstico por imagen , Miedo/psicología , Femenino , Lateralidad Funcional , Hipocampo/diagnóstico por imagen , Hipocampo/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Proteínas Proto-Oncogénicas c-fos/metabolismo , Distribución Aleatoria , Ratas , Ratas Long-Evans , Factores de Tiempo , Adulto Joven
20.
Cortex ; 84: 15-33, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27665526

RESUMEN

We assessed whether perceptual richness, a defining feature of episodic memory, depends on the engagement and integrity of the hippocampus during episodic memory retrieval. We tested participants' memory for complex laboratory events (LEs) that differed in perceptual content: short stories were either presented as perceptually rich film clips or as perceptually impoverished narratives. Participants underwent functional magnetic resonance imaging (fMRI) while retrieving these LEs (narratives and clips), as well as events from their personal life (autobiographical memories). In a group of healthy adults, a conjunction analysis showed that both real-life and laboratory memories engaged overlapping regions from an autobiographical memory (AM) retrieval network, indicating that laboratory memories mimicked autobiographical events successfully. A direct contrast between the film clip and the narrative laboratory conditions identified regions activated by the retrieval of perceptual memory content, which included the right hippocampus, parahippocampal gyrus, middle occipital gyrus and precuneus. In individuals with medial temporal lobe epilepsy (mTLE) originating from the right hippocampus, the magnitude of this "perceptually rich" signal was reduced significantly, which is consistent with evidence of reduced perceptual memory content in this clinical population. In healthy controls, right hippocampal activation also correlated positively with a behavioral measure of perceptual content in the clip condition. Thus, right hippocampal activity contributed to the retrieval of perceptual episodic memory content in the healthy brain, while right hippocampal damage disrupted activation in regions that process perceptual memory content. Our results suggest that the hippocampus contributes to recollection by retrieving and integrating perceptual details into vivid memory constructs.


Asunto(s)
Mapeo Encefálico , Hipocampo/fisiología , Trastornos de la Memoria/fisiopatología , Memoria Episódica , Recuerdo Mental/fisiología , Adulto , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino
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