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Understanding the factors contributing to optimal cognitive function throughout the aging process is essential to better understand successful cognitive aging. Processing speed is an age sensitive cognitive domain that usually declines early in the aging process; however, this cognitive skill is essential for other cognitive tasks and everyday functioning. Evaluating brain network interactions in cognitively healthy older adults can help us understand how brain characteristics variations affect cognitive functioning. Functional connections among groups of brain areas give insight into the brain’s organization, and the cognitive effects of aging may relate to this large-scale organization. To follow-up on our prior work, we sought to replicate our findings regarding network segregation’s relationship with processing speed. In order to address possible influences of node location or network membership we replicated the analysis across 4 different node sets.
Participants and Methods:
Data were acquired as part of a multi-center study of 85+ cognitively normal individuals, the McKnight Brain Aging Registry (MBAR). For this analysis, we included 146 community-dwelling, cognitively unimpaired older adults, ages 85-99, who had undergone structural and BOLD resting state MRI scans and a battery of neuropsychological tests. Exploratory factor analysis identified the processing speed factor of interest. We preprocessed BOLD scans using fmriprep, Ciftify, and XCPEngine algorithms. We used 4 different sets of connectivity-based parcellation: 1)MBAR data used to define nodes and Power (2011) atlas used to determine node network membership, 2) Younger adults data used to define nodes (Chan 2014) and Power (2011) atlas used to determine node network membership, 3) Older adults data from a different study (Han 2018) used to define nodes and Power (2011) atlas used to determine node network membership, and 4) MBAR data used to define nodes and MBAR data based community detection used to determine node network membership.
Segregation (balance of within-network and between-network connections) was measured within the association system and three wellcharacterized networks: Default Mode Network (DMN), Cingulo-Opercular Network (CON), and Fronto-Parietal Network (FPN). Correlation between processing speed and association system and networks was performed for all 4 node sets.
Results:
We replicated prior work and found the segregation of both the cortical association system, the segregation of FPN and DMN had a consistent relationship with processing speed across all node sets (association system range of correlations: r=.294 to .342, FPN: r=.254 to .272, DMN: r=.263 to .273). Additionally, compared to parcellations created with older adults, the parcellation created based on younger individuals showed attenuated and less robust findings as those with older adults (association system r=.263, FPN r=.255, DMN r=.263).
Conclusions:
This study shows that network segregation of the oldest-old brain is closely linked with processing speed and this relationship is replicable across different node sets created with varied datasets. This work adds to the growing body of knowledge about age-related dedifferentiation by demonstrating replicability and consistency of the finding that as essential cognitive skill, processing speed, is associated with differentiated functional networks even in very old individuals experiencing successful cognitive aging.
A mandate framework is proposed for delegating monetary policy to an instrument-independent, but goal-dependent central bank that emphasizes simplicity in both the objectives entering the welfare criterion and those in the instrument rule. It consists of: (i) a simple quadratic loss function penalizing deviations from target variables; (ii) a welfare-optimized, Taylor-type log-linear nominal interest-rate rule with targets that match those in the loss function; (iii) a zero-lower-bound (ZLB) constraint on the nominal interest rate imposing a low unconditional probability of ZLB episodes; and (iv) a long-run inflation target. In an estimated New Keynesian model with these features, we find that for a quarterly probability of 5%, an optimal annual inflation target is close to 2%, weights for real variables in the loss function are small compared with inflation except for the real wage growth mandate and the optimized rules mimic a price-level rule.
Despite the prevalence of antidepressant-related sexual side effects, comparisons of treatments for these problematic side effects are lacking.
Methods
To address this, we performed a systematic review and Bayesian network meta-analysis to compare interventions for antidepressant-induced sexual dysfunction in adults. Using PubMed and clinicaltrials.gov, we identified published and unpublished prospective treatment trials from 1985 to September 2020 (primary outcome: the Arizona sexual experience scale [ASEX] score). The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework.
Results
We identified 57 citations (27 randomized controlled trials, 66 treatment arms, 27 open-label trials, and 3 crossover trials) that evaluated 33 interventions (3108 patients). In the systematic review, 44% (25/57) of trials reported successful interventions; this was more common in open-label (70%, 19/27) compared to placebo-controlled studies (22%, 6/27). In the meta-analysis of placebo-controlled studies that used the ASEX (N = 8), pycnogenol was superior to placebo (standardized mean difference: −1.8, 95% credible interval [CrI]: [−3.7 to 0.0]) and there was evidence that, at a 6% threshold, sildenafil improved sexual dysfunction (standardized mean difference: −1.2, 95% CrI [−2.5 to 0.1]). In the meta-analysis including single-arm studies (15 studies), treatment response was more common with sildenafil, tianeptine, maca, tiagabine, and mirtazapine compared to placebo, but these differences failed to reach statistical significance.
Conclusions
While heterogeneity across randomized controlled trials complicates identifying the single best intervention, multiple trials suggest that sildenafil ameliorates antidepressant-induced sexual dysfunction. More randomized controlled trials are needed to examine the putative efficacy of other interventions.
Many studies have reported an increased risk of autism spectrum disorder (ASD) associated with some maternal diagnoses in pregnancy. However, such associations have not been studied systematically, accounting for comorbidity between maternal disorders. Therefore our aim was to comprehensively test the associations between maternal diagnoses around pregnancy and ASD risk in offspring.
Methods
This exploratory case–cohort study included children born in Israel from 1997 to 2008, and followed up until 2015. We used information on all ICD-9 codes received by their mothers during pregnancy and the preceding year. ASD risk associated with each of those conditions was calculated using Cox proportional hazards regression, adjusted for the confounders (birth year, maternal age, socioeconomic status and number of ICD-9 diagnoses during the exposure period).
Results
The analytic sample consisted of 80 187 individuals (1132 cases, 79 055 controls), with 822 unique ICD-9 codes recorded in their mothers. After extensive quality control, 22 maternal diagnoses were nominally significantly associated with offspring ASD, with 16 of those surviving subsequent filtering steps (permutation testing, multiple testing correction, multiple regression). Among those, we recorded an increased risk of ASD associated with metabolic [e.g. hypertension; HR = 2.74 (1.92–3.90), p = 2.43 × 10−8], genitourinary [e.g. non-inflammatory disorders of cervix; HR = 1.88 (1.38–2.57), p = 7.06 × 10−5] and psychiatric [depressive disorder; HR = 2.11 (1.32–3.35), p = 1.70 × 10−3] diagnoses. Meanwhile, mothers of children with ASD were less likely to attend prenatal care appointment [HR = 0.62 (0.54–0.71), p = 1.80 × 10−11].
Conclusions
Sixteen maternal diagnoses were associated with ASD in the offspring, after rigorous filtering of potential false-positive associations. Replication in other cohorts and further research to understand the mechanisms underlying the observed associations with ASD are warranted.
The Canadian Multiple Sclerosis Working Group has updated its treatment optimization recommendations (TORs) on the optimal use of disease-modifying therapies for patients with all forms of multiple sclerosis (MS). Recommendations provide guidance on initiating effective treatment early in the course of disease, monitoring response to therapy, and modifying or switching therapies to optimize disease control. The current TORs also address the treatment of pediatric MS, progressive MS and the identification and treatment of aggressive forms of the disease. Newer therapies offer improved efficacy, but also have potential safety concerns that must be adequately balanced, notably when treatment sequencing is considered. There are added discussions regarding the management of pregnancy, the future potential of biomarkers and consideration as to when it may be prudent to stop therapy. These TORs are meant to be used and interpreted by all neurologists with a special interest in the management of MS.
OBJECTIVES/SPECIFIC AIMS: Objective: apply checkpoint inhibitors that are specific to the exhaustive markers expressed on tumor CD8+ T-cells ex vivo in order to improve cytokine release and cytotoxic function in comparison to two control groups: (1.) T-cells that receive no antibodies; (2.) T-cells that receive standard inhibition with PD-1 and CTLA-4 antibodies only. Long-term objective: provide personalized medicine in the treatment of HCC by using checkpoint inhibitors that are specific to the receptors expressed by an individual tumor. METHODS/STUDY POPULATION: The study population includes patients undergoing liver transplantation or surgical resection for HCC. Two grams of tumor, two grams of healthy liver tissue at least one centimeter from the tumor margin, and 50 milliliters of blood will be obtained. Solid tissue will be mechanically and enzymatically disrupted and CD8+ T-cells will be isolated from all sites. Using flow cytometry, the expression of surface receptors PD-1, CTLA-4, LAG-3, TIM-3, BTLA, CD244, and CD160 will be categorized in each tissue to identify which receptors are upregulated in the tumor microenvironment. Up to three antibodies specific to the upregulated receptor(s) on the tumor T-cells will be applied per specimen. The experimental arm will receive these antibodies and co-stimulation with CD3/CD28 and will be compared to two controls. One control will receive only CD3/CD28, and the other will receive CD3/CD28 in addition to the standard combination of PD-1 and CTLA-4 inhibitors. From each condition, flow cytometry will be used to assess the mean production of interleukin-2, tumor necrosis factor-α, interferon-γ, granzyme B, and perforin expression as an assessment of T-cell function. RESULTS/ANTICIPATED RESULTS: Preliminary data from the peripheral blood of healthy controls confirms that the developed flow cytometry panels effectively identify the surface receptors and cytokine production of CD8+ T-cells. Two patients have successfully been enrolled in this study. It is predicted that T-cells extracted from the tumor will express more inhibitory receptors than normal liver or peripheral blood and will have increased function after they are targeted with checkpoint inhibitors that are specific to the inhibitory surface receptors they express. DISCUSSION/SIGNIFICANCE OF IMPACT: HCC is the second leading cause of cancer-related death worldwide and therapeutic options are limited for patients who are not surgical candidates. T-cells are a critical component of the anti-tumor response to HCC. However, T-cells can develop an exhausted phenotype characterized by up-regulated inhibitory receptors (PD-1, CTLA-4, LAG-3, TIM-3, CD-244, CD-160, BTLA) and decreased function, allowing for immune escape. Clinical trials using combined checkpoint inhibition with PD-L1 and CTLA-4 antibodies have been considered a breakthrough for patients with advanced HCC, as up to 25% show an objective tumor response. The explanation for the varied susceptibility to checkpoint inhibition remains unknown and is hypothesized to be secondary to inconsistencies in the expression of surface inhibitory receptors. Although inhibitory receptor expression has been shown to be upregulated under conditions of hepatitis and/or HCC, there has been no single study to effectively investigate the expression of all known inhibitors in order to better explore the interplay between them. It will be of great academic interest and clinical purpose to evaluate individual receptor expression and engage the correlating antibodies given the possibility of synergism between receptors and the need for a more profound anti-tumor T-cell response in HCC.
By
Jeremy I. Bulow, Graduate School of Business, Stanford University,
Jonathan Levin, Graduate School of Business, Stanford University,
Paul R. Milgrom, Department of Economics, Stanford University
Since being pioneered by the U.S. in 1994, simultaneous ascending auctions have become a common mechanism to allocate spectrum rights. Spectrum auctions can involve billions of dollars and companies bidding in these auctions regularly create specialized bidding teams and hire experts in auction theory to develop bidding strategies. Nevertheless, the results can be surprising. In the FCC's auction of Advanced Wireless Service spectrum, price arbitrage failed so dramatically that one new entrant was able to purchase essentially nationwide coverage for about a third (more than a billion dollars) less than what incumbent carriers paid for equivalent spectrum in the same auction. At the same time, the other prospective nationwide entrant exited the auction early and filed a letter with the FCC claiming that the auction rules disadvantaged new entrants!
Results of this sort raise questions for economists. Does the apparent failure of the Law of One Price indicate a fundamental flaw in auction design? If not, why must such auctions be complicated? What are the issues that create strategic complexity for bidders? And to what extent can the tools of economic theory provide insights that facilitate effective bidding in highly complex environments?
We start by explaining some of the reasons why large spectrum auctions are necessarily complicated, and why the Law of One Price can fail so dramatically in a spectrum auction.We emphasize two difficulties facing bidders: exposure problems, which are essentially the problems of bidders wishing to acquire complementary licenses, and budget constraints, which we argue are ubiquitous.We explain why these difficulties make bidding in simultaneous ascending auctions complicated, and also why they would complicate bidding in other auction designs.
Exposure problems create fundamental difficulties for a new entrant seeking to compete head-to-head with incumbent nationwide wireless carriers in the US. Such an entrant needs to acquire adequate bandwidth in every major metropolitan area, but because licenses covering cities or regions are sold individually, the entrant could commit to spending billions of dollars winning spectrum licenses before discovering that the total price for the bundle of licenses it seeks makes the whole entry unaffordable or unprofitable. It could then be left to dispose of extensive holdings at fire-sale prices.
The initial government debt-to-gross domestic product (GDP) ratio and the government's commitment play a pivotal role in determining the welfare-optimal speed of fiscal consolidation in the management of a debt crisis. Under commitment, for low or moderate initial government debt-to-GDP ratios, the optimal consolidation is very slow. A faster pace is optimal when the economy starts from a high level of public debt implying high sovereign risk premia, unless these are suppressed via a bailout by official creditors. Under discretion, the cost of not being able to commit is reflected into a quick consolidation of government debt. Simple monetary–fiscal rules with passive fiscal policy, designed for an environment with “normal shocks,” perform reasonably well in mimicking the Ramsey-optimal response to one-off government debt shocks. When the government can issue also long-term bonds—under commitment—the optimal debt consolidation pace is slower than in the case of short-term bonds only, and entails an increase in the ratio between long- and short-term bonds.
A comparison of two electron microscopy techniques used to determine the polarity of GaN nanowires is presented. The techniques are convergent beam electron diffraction (CBED) in TEM mode and annular bright field (ABF) imaging in aberration corrected STEM mode. Both measurements were made at nominally the same locations on a variety of GaN nanowires. In all cases the two techniques gave the same polarity result. An important aspect of the study was the calibration of the CBED pattern rotation relative to the TEM image. Three different microscopes were used for CBED measurements. For all three instruments there was a substantial rotation of the diffraction pattern (120 or 180°) relative to the image, which, if unaccounted for, would have resulted in incorrect polarity determination. The study also shows that structural defects such as inversion domains can be readily identified by ABF imaging, but may escape identification by CBED. The relative advantages of the two techniques are discussed.
Objective: Idiopathic normal pressure hydrocephalus (INPH) is a neurological disorder presenting with gait, cognitive, and bladder symptoms in the context of ventricular enlargement. Although gait is the primary indicator for treatment candidacy and outcome, additional monitoring tools are needed. Line Tracing Test (LTT) and Serial Dotting Test (SDT), two psychomotor tasks, have been introduced as potential outcome measures but have not been widely studied. This preliminary study examined whether LTT and SDT are sensitive to motor dysfunction in INPH and determined if accuracy and time are important aspects of performance. Methods: Eighty-four INPH subjects and 36 healthy older adults were administered LTT and SDT. Novel error scoring procedures were developed to make scoring practical and efficient; interclass correlation showed good reliability of scoring procedures for both tasks (0.997; p<.001). Results: The INPH group demonstrated slower performance on SDT (p<.001) and made a greater number of errors on both tasks (p<.001). Combined Time/Error scores revealed poorer performance in the INPH group for original-LTT (p<.001), modified-LTT (p≤.001) and SDT (p<.001). Conclusions: These findings indicate LTT and SDT may prove useful for monitoring psychomotor skills in INPH. While completion time reflects impaired processing speed, reduced accuracy may suggest planning and self-monitoring difficulties, aspects of executive functioning known to be compromised in INPH. This is the first study to underscore the importance of performance accuracy in INPH and introduce practical/reliable error scoring for these tasks. Future work will establish reliability and validity of these measures and determine their utility as outcome tools. (JINS, 2016, 22, 341–349)