Patient, operative and pain management factors influencing inpatient compared with surgical day care mastectomy procedures at a community hospital.

BACKGROUND: The COVID-19 pandemic highlighted the importance of maximizing same-day discharge after surgery to mitigate potential patient harms associated with inpatient admission and conserve valuable hospital resources. Adoption of same-day discharge after breast surgery, particularly mastectomy, has been slow despite recent research suggesting the physical and psychological benefits of same-day discharge after surgery. We sought to identify factors associated with inpatient compared with surgical day care mastectomy procedures at a community hospital in Vernon, British Columbia. METHODS: We conducted a retrospective chart review of all patients who underwent a total mastectomy without reconstruction at Vernon Jubilee Hospital, a 196-bed community hospital, between April 2016 and March 2019. Patient characteristics, operative variables and pain management were compared between inpatient and surgical day care mastectomy procedures. We also compared 7-day readmission, reoperation and complications. RESULTS: A total of 187 mastectomy patients were analyzed with 72 (38.5%) surgical day care procedures. Factors associated with inpatient procedures included longer operative time (66.1 min v. 53.5 min, p = 0.001), bilateral mastectomy (91% v. 9%, p = 0.01) and suspected or confirmed obstructive sleep apnea (32% v. 17%, p = 0.04). Preoperative acetaminophen (83% v. 17%, p < 0.001), multilevel intercostal block (83% v. 17%, p < 0.001) and a prescription for acetaminophen plus tramadol (58% v. 42%, p < 0.001) were associated with day care surgeries. There were no significant differences between the inpatient and surgical day care groups with respect to 7-day readmission, reoperation or postoperative complications. CONCLUSION: We found no significant differences in surgical outcomes between inpatients and those with same-day discharge after mastectomy procedures. These findings add to the growing body of evidence that surgical day care mastectomy procedures are safe in the community setting.

Increasing the amplitude of intrinsic theta in the human brain.

In a mouse study we found increased myelination of pathways surrounding the anterior cingulate cortex (ACC) following stimulation near the theta rhythm (4-8 Hz), and evidence that this change in connectivity reduced behavioral anxiety. We cannot use the optogenetic methods with humans that were used in our mouse studies. This paper examines whether it is possible to enhance intrinsic theta amplitudes in humans using less invasive methods. The first experiment compares electrical, auditory and biofeedback as methods for increasing intrinsic theta rhythm amplitudes in the Anterior Cingulate Cortex (ACC). These methods are used alone or in conjunction with a task designed to activate the same area. The results favor using electrical stimulation in conjunction with a task targeting this region. Stimulating the ACC increases intrinsic theta more in this area than in a control area distant from the site of stimulation, suggesting some degree of localization of the stimulation. In Experiment 2, we employed electrical stimulation with the electrodes common to each person, or with electrodes selected from an individual head model. We targeted the ACC or Motor Cortex (PMC). At baseline, intrinsic theta is higher in the ACC than the PMC. In both areas, theta can be increased in amplitude by electrical stimulation plus task. In the PMC, theta levels during stimulation plus task are not significantly higher than during task alone. There is no significant difference between generic and individual electrodes. We discuss steps needed to determine whether we can use the electrical stimulation + task to improve the connectivity of white matter in different brain areas.

Perceptions of masculinity and body image in men with prostate cancer: the role of exercise.

PURPOSE: The goal of this study was to explore the association between levels of exercise and patterns of masculinity, body image, and quality of life in men undergoing diverse treatment protocols for prostate cancer. METHODS: Fifty men with prostate cancer (aged 42-86) completed self-report measures. Self-reported measures included the following: the Godin Leisure Time Exercise Questionnaire (GLTEQ), Masculine Self-esteem Scale (MSES), Personal Attributes Questionnaire (PAQ), Body Image Scale (BIS), and the Functional Assessment of Cancer Therapy-Prostate (FACT-P). Masculinity, body image, and quality of life scores were compared between men obtaining recommended levels of exercise (aerobic or resistance) and those not obtaining recommended level of exercise. Secondary outcomes included the association between masculinity, body image, and quality of life scores as they relate to exercise levels. RESULTS: There were significantly higher scores of masculinity (p < 0.01), physical well-being (p < 0.05), prostate cancer specific well-being (p < 0.05), and overall quality of life (p < 0.05) in those obtaining at least 150 min of moderate to vigorous aerobic exercise. In the 48% of men who had never received androgen deprivation therapy, significantly higher levels of masculinity, body image, and quality of life were observed in those meeting aerobic guidelines. CONCLUSIONS: Whether treatment includes androgen deprivation or not, men who participate in higher levels of aerobic exercises report higher levels of masculinity, improved body image, and quality of life than those who are inactive. Future longitudinal research is required evaluating exercise level and its effect on masculinity and body image.

Late initiation of combination antiretroviral therapy in Canada: a call for a national public health strategy to improve engagement in HIV care.

INTRODUCTION: Combination antiretroviral therapy (ART) significantly decreases morbidity, mortality and HIV transmission. We aimed to characterize the timing of ART initiation based on CD4 cell count from 2000 to 2012 and identify factors associated with late initiation of treatment. METHODS: Participants from the Canadian Observational Cohort (CANOC), a multi-site cohort of HIV-positive adults initiating ART naively after 1 January 2000, in three Canadian provinces (British Columbia, Ontario and Québec) were included. Late initiation was defined as a CD4 count <200 cells/mm(3) or an AIDS-defining illness before ART initiation (baseline). Temporal trends were assessed using the Cochran-Armitage test, and independent correlates of late initiation were identified using logistic regression. RESULTS: In total, 8942 participants (18% female) of median age 40 years (Q1-Q3 33-47) were included. The median baseline CD4 count increased from 190 cells/mm(3) (Q1-Q3 80-320) in 2000 to 360 cells/mm(3) (Q1-Q3 220-490) in 2012 (p<0.001). Overall, 4274 participants (48%) initiated ART with a CD4 count <200 cells/mm(3) or AIDS-defining illness. Late initiation was more common among women, non-MSM, older individuals, participants from Ontario and BC (vs. Québec), persons with injection drug use (IDU) history and individuals starting ART in earlier calendar years. In sub-analysis exploring recent (2008 to 2012) predictors using an updated CD4 criterion (<350 cells/mm(3)), IDU and residence in BC (vs. Québec) were no longer significant correlates of late initiation. CONCLUSIONS: This analysis documents increasing baseline CD4 counts over time among Canadians initiating ART. However, CD4 counts at ART initiation remain below contemporary treatment guidelines, highlighting the need for strategies to improve earlier engagement in HIV care.

EEG source localization: Sensor density and head surface coverage.

BACKGROUND: The accuracy of EEG source localization depends on a sufficient sampling of the surface potential field, an accurate conducting volume estimation (head model), and a suitable and well-understood inverse technique. The goal of the present study is to examine the effect of sampling density and coverage on the ability to accurately localize sources, using common linear inverse weight techniques, at different depths. Several inverse methods are examined, using the popular head conductivity. NEW METHOD: Simulation studies were employed to examine the effect of spatial sampling of the potential field at the head surface, in terms of sensor density and coverage of the inferior and superior head regions. In addition, the effects of sensor density and coverage are investigated in the source localization of epileptiform EEG. RESULTS: Greater sensor density improves source localization accuracy. Moreover, across all sampling density and inverse methods, adding samples on the inferior surface improves the accuracy of source estimates at all depths. COMPARISON WITH EXISTING METHODS: More accurate source localization of EEG data can be achieved with high spatial sampling of the head surface electrodes. CONCLUSIONS: The most accurate source localization is obtained when the voltage surface is densely sampled over both the superior and inferior surfaces.

Localizing movement-related primary sensorimotor cortices with multi-band EEG frequency changes and functional MRI.

Electroencephalographic (EEG) oscillations in multiple frequency bands can be observed during functional activity of the cerebral cortex. An important question is whether activity of focal areas of cortex, such as during finger movements, is tracked by focal oscillatory EEG changes. Although a number of studies have compared EEG changes to functional MRI hemodynamic responses, we can find no previous research that relates the fMRI hemodynamic activity to localization of the multiple EEG frequency changes observed in motor tasks. In the present study, five participants performed similar thumb and finger movement tasks in parallel EEG and functional MRI studies. We examined changes in five frequency bands (from 5-120 Hz) and localized them using 256 dense-array EEG (dEEG) recordings and high-resolution individual head models. These localizations were compared with fMRI localizations in the same participants. Results showed that beta-band (14-30 Hz) desynchronizations (power decreases) were the most robust effects, appearing in all individuals, consistently localized to the hand region of the primary motor cortex, and consistently aligned with fMRI localizations.

Computational modeling of human head electromagnetics for source localization of milliscale brain dynamics.

Understanding the milliscale (temporal and spatial) dynamics of the human brain activity requires high-resolution modeling of head electromagnetics and source localization of EEG data. We have developed an automated environment to construct individualized computational head models from image segmentation and to estimate conductivity parameters using electrical impedance tomography methods. Algorithms incorporating tissue inhomogeneity and impedance anisotropy in electromagnetics forward simulations have been developed and parallelized. The paper reports on the application of the environment in the processing of realistic head models, including conductivity inverse estimation and lead field generation for use in EEG source analysis.

Dynamics of task sets: evidence from dense-array event-related potentials.

Prior research suggests that task sets facilitate coherent, goal-directed behavior by providing an internal, contextual frame that biases selection toward context-relevant stimulus attributes and responses. Questions about how task sets are engaged, maintained, and shifted have recently become a major focus of research on executive control processes. We employed dense-array (128-channel) event-related potential (ERP) methodology to examine the dynamics of brain systems engaged during the preparation and implementation of task switching. The EEG was recorded while participants performed letter and digit judgments to pseudorandomly-ordered, univalent (#3, A%) and bivalent (G5) stimulus trials, with the appropriate task cued by a colored rectangle presented 450 ms before target onset. Results revealed spatial and temporal variations in brain activity that could be related to preparatory processes common to both switch and repeat trials, switch-specific control processes engaged to reconfigure and maintain task set under conflict, and visual priming benefits of task repetition. Despite extensive practice and improvement, both behavioral and ERP results indicated that subjects maintained high levels of executive control processing with extended task engagement. The patterns of ERP activity obtained in the present study fit well with functional neuroanatomical models of self-regulation of action. The frontopolar and right-lateralized frontal switch effects obtained in the present study are consistent with the role of these regions in adapting to changing contextual contingencies. In contrast, the centroparietal P3b and N384 effects related to the contextual ambiguity of bivalent trials are consistent with the context monitoring and updating functions associated with the posterior cingulate learning circuit.

DNA methylation, nucleosome formation and positioning.

Recent mapping of nucleosome positioning on several long gene regions subject to DNA methylation has identified instances of nucleosome repositioning by this base modification. The evidence for an effect of CpG methylation on nucleosome formation and positioning in chromatin is reviewed here in the context of the complex sequence-structure requirements of DNA wrapping around the histone octamer and the role of this epigenetic mark in gene repression.

A determining influence for CpG dinucleotides on nucleosome positioning in vitro.

DNA sequence information that directs the translational positioning of nucleosomes can be attenuated by cytosine methylation when a short run of CpG dinucleotides is located close to the dyad axis of the nucleosome. Here, we show that point mutations introduced to re-pattern methylation at the (CpG)3 element in the chicken betaA-globin promoter sequence themselves strongly influenced nucleosome formation in reconstituted chromatin. The disruptive effect of cytosine methylation on nucleosome formation was found to be determined by the sequence context of CpG dinucleotides, not just their location in the positioning sequence. Additional mutations indicated that methylation can also promote the occupation of certain nucleosome positions. DNase I analysis demonstrated that these genetic and epigenetic modifications altered the structural characteristics of the (CpG)3 element. Our findings support a proposal that the intrinsic structural properties of the DNA at the -1.5 site, as occupied by (CpG)3 in the nucleosome studied, can be decisive for nucleosome formation and stability, and that changes in anisotropic DNA bending or flexibility at this site explain why nucleosome positioning can be exquisitely sensitive to genetic and epigenetic modification of the DNA sequence.

Frontal and posterior sources of event-related potentials in semantic comprehension.

An important question in brain and language research is how activity in multiple brain networks is coordinated over time during semantic comprehension. To address this question, we applied spatiotemporal source analysis to event-related potentials (ERPs) recorded as subjects read words that were meaningful or incongruous in the context of a sentence (N400 paradigm). The incongruous word was placed either early in the sentence or at the end. Source analysis showed activity in language areas of the left hemisphere, right temporal cortex and medial limbic cortex. The initial detection of semantic incongruity (approximately 250 ms) engaged the left prefrontal cortex and left anterior cingulate. In the critical (300-500 ms) interval, regional sources in left and right lateral prefrontal cortex, right temporal cortex, and both anterior and posterior cingulate were responsive to the semantic manipulation. Left hemisphere activity preceded right hemisphere activity, and semantic effects in frontal regions began earlier and were more sustained than the transient effects within posterior cortical regions. Findings are discussed with respect to recent theories of corticothalamic and corticolimbic networks in attention and semantic processing.

Corticolimbic mechanisms in emotional decisions.

Midline frontolimbic networks are engaged in monitoring simple actions. They may also provide evaluative control for more complex decisions. Subjects read a trait-descriptive word and responded either "yes" or "no" within 1,500 ms whether it was self-descriptive. By 300 ms, an electrophysiological discrimination between good and bad words was seen over centromedial regions of the frontal lobe for both friend and self-decisions. By 350 ms, an interaction effect between evaluation and endorsement appeared, and by 500 ms, activity specific to self-evaluation was seen in both anterior and posterior midline sites. An evaluative decision thus begins by recruiting motivational and semantic influences within limbic networks, and these influences appear to shape the development of the decision within multiple neocortical regions.