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61.
Moriah E. Thomason Jasmine L. Hect Rebecca Waller Paul Curtin 《Neuropsychopharmacology》2021,46(10):1839
Studies reporting significant associations between maternal prenatal stress and child outcomes are frequently confounded by correlates of prenatal stress that influence the postnatal rearing environment. The major objective of this study is to identify whether maternal prenatal stress is associated with variation in human brain functional connectivity prior to birth. We utilized fetal fMRI in 118 fetuses [48 female; mean age 32.9 weeks (SD = 3.87)] to evaluate this association and further addressed whether fetal neural differences were related to maternal health behaviors, social support, or birth outcomes. Community detection was used to empirically define networks and enrichment was used to isolate differential within- or between-network connectivity effects. Significance for χ2 enrichment was determined by randomly permuting the subject pairing of fetal brain connectivity and maternal stress values 10,000 times. Mixtures modelling was used to test whether fetal neural differences were related to maternal health behaviors, social support, or birth outcomes. Increased maternal prenatal negative affect/stress was associated with alterations in fetal frontoparietal, striatal, and temporoparietal connectivity (β = 0.82, p < 0.001). Follow-up analysis demonstrated that these associations were stronger in women with better health behaviors, more positive interpersonal support, and lower overall stress (β = 0.16, p = 0.02). Additionally, magnitude of stress-related differences in neural connectivity was marginally correlated with younger gestational age at delivery (β = −0.18, p = 0.05). This is the first evidence that negative affect/stress during pregnancy is reflected in functional network differences in the human brain in utero, and also provides information about how positive interpersonal and health behaviors could mitigate prenatal brain programming.Subject terms: Risk factors, Neural patterning 相似文献
62.
Calibration of BOLD fMRI using breath holding reduces group variance during a cognitive task 总被引:1,自引:0,他引:1
The proportionality of blood oxygen level-dependent (BOLD) response during a cognitive task and that from a hypercapnic challenge was investigated in cortical structures involved in working memory (WM). Breath holding (BH) following inspiration was used to induce a BOLD response characteristic of regional vasomotor reactivity but devoid of metabolic changes. BOLD effects measured during BH were used to normalize individual subject activations during WM, which effectively reduced the confounding influence of individual- and region-specific differences in hemodynamic responsivity common to both tasks. In a study of seven subjects, the BH calibration reduced intersubject variability in WM effect amplitude by 24.8% (P < 0.03). Reduced intersubject variability resulted in a 23.7% increase in group WM activation voxel extent significant at P < 0.001, with further increases at more stringent thresholds. Because the BH task does not require CO(2) inhalation or other invasive manipulations and is broadly applicable across cortical regions, the proposed approach is simple to implement and may be beneficial for use not only in quantitative group fMRI analyses, but also for multicenter and longitudinal studies. 相似文献
63.
Default-mode function and task-induced deactivation have overlapping brain substrates in children 总被引:1,自引:0,他引:1
The regions that comprise the functionally connected resting-state default-mode network (DMN) in adults appear to be the same as those that are characterized by task-induced decreases in blood-oxygen-level-dependent (BOLD) signal. Independent component analysis can be used to produce a picture of the DMN as an individual rests quietly in the scanner. Contrasts across conditions in which cognitive load is parametrically modulated can delineate neural structures that have decreases in activation in response to high-demand task conditions. Examination of the degree to which these networks subsume dissociable brain substrates, and of the degree to which they overlap, provides insight concerning their purpose, function, and the nature of their associations. Few studies have examined the DMN in children, and none have tested whether the neural regions that comprise the DMN during a resting condition are the same regions that show reduced activity when children engage in cognitive tasks. In this paper we describe regions that show both task-related decreases and spontaneous intrinsic activity at rest in children, and we examine the co-localization of these networks. We describe ways in which the DMN in 7-12-year-old children is both similar to and different from the DMN in adults; moreover, we document that task-induced deactivations and default-mode resting-state activity in children share common neural substrates. It appears, therefore, that even before adolescence a core aspect of task-induced deactivation involves reallocating processing resources that are active at rest. We describe how future studies assessing the development of these systems would benefit from examining these constructs as part of one continuous system. 相似文献
64.
Eyal Nof Osnat Gurevitz Shemy Carraso David Bar-Lev David Luria Sharona Bachar Michael Eldar Michael Glikson 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2008,10(1):35-39
AIMS: To compare different coronary sinus (CS) leads and delivery systems (DSs) for left ventricular pacing. METHODS AND RESULTS: Delivery systems-related (including CS dissection and dislocations during sheath/stylet removal) and lead-related (including failure to accomplish implantations and long-term malfunctions resulting in abandonment or repositioning/replacing of the lead) complications between systems and leads were compared. We used Medtronic (MDT) attain DS (n = 123) with over-the-wire (OTW) (4193, 4194) and stylet-driven (2187) leads, and Guidant (GDT) DS (n = 126) with Easytrak OTW leads (4513, 4518, and 4525). Coronory sinus dissection occurred in 6/123 (5%) cases using the MDT DS vs. 7/126 (6%) with GDT DS (P= NS). Dislocations during sheath/stylet removal occurred in 8/123 cases (6%) with MDT DS, and in 8/126 (6%) with GDT DS (P= NS). Failure to achieve successful implantation occurred in 6/32 (19%) of the 2187 leads, in 11/87(13%) of the 4193/4194 leads, in 7/94(7%) of the 4513/4518 leads, and in 4/29 (14%) of the 4525 leads (P= NS). Long-term lead-related complications occurred in 5/32 (15%) of the 2187 leads, 19/80 (23%) of the 4193/4194 leads, 19/93 (20%) of the 4513/4518 leads, and 2/28 (7%) of the 4525 leads (P= NS). CONCLUSION: No significant differences in complication rates between systems and leads were observed. 相似文献
65.
Moriah P. Bellissimo Karla I. Galaviz Meredith C. Paskert Felipe Lobelo 《Mayo Clinic proceedings. Mayo Clinic》2018,93(10):1375-1396
Objective
To estimate the pooled effects of community-based, recreational-level group sports on cardiometabolic risk factors and fitness parameters among adults.Participants and Methods
We systematically searched PubMed, EMBASE, PsychINFO, CINAHL, and Web of Science electronic databases for English-language articles reporting the effectiveness of recreational-level group sports published between January 1, 1965, and January 17, 2017. We extracted baseline and end of intervention means for cardiometabolic and fitness parameters. Random- or fixed-effects meta-analyses were used to obtain pooled before and after change in outcome means within intervention participants and between groups.Results
From 2491 screened titles, 23 publications were included (902 participants; mean ± SD age, 46.6±11.7 years), comprising 21 soccer and 2 rugby interventions. Intervention participants achieved larger improvements (mean [95% CI]) compared with control subjects in weight (?1.44 kg [?1.79 to ?1.08 kg]), body mass index (?0.88 kg/m2 [?1.73 to ?0.03 kg/m2]), waist circumference (?0.77 cm [?1.21 to ?0.33 cm]), body fat (?1.8% [?3.12% to ?0.49%]), total cholesterol level (?0.33 mmol/L [?0.53 to ?0.13 mmol/L]), low-density lipoprotein cholesterol level (?0.35 mmol/L [?0.54 to ?0.15 mmol/L]), systolic blood pressure (?5.71 mm Hg [?7.98 to ?3.44 mm Hg]), diastolic blood pressure (?3.36 mm Hg [?4.93 to ?1.78 mm Hg]), maximum oxygen consumption (3.93 mL/min per kg [2.96-4.91 mL/min]), and resting heart rate (?5.51 beats/min [?7.37 to ?3.66 beats/min]). Most studies (16) were classified as high quality, and we found no evidence of publication bias.Conclusion
We found significant cardiometabolic and fitness improvements following group sport participation, primarily recreational soccer. These findings suggest that group sport interventions are promising strategies for reducing cardiometabolic risk in adults. 相似文献66.
67.
Korthuis PT Saha S Fleishman JA McGrath MM Josephs JS Moore RD Gebo KA Hellinger J Beach MC;HIV Research Network 《Journal of general internal medicine》2008,23(12):2046-2052
BACKGROUND Patient-centered care—including the domains of access and communication—is an important determinant of positive clinical outcomes.
OBJECTIVE To explore associations between race and HIV-infected patients’ experiences of access and communication.
DESIGN This was a cross-sectional survey.
PARTICIPANTS Nine hundred and fifteen HIV-infected adults receiving care at 14 U.S. HIV clinics.
MEASUREMENTS Dependent variables included patients’ reports of travel time to their HIV care site and waiting time to see their HIV provider
(access) and ratings of their HIV providers on always listening, explaining, showing respect, and spending enough time with
them (communication). We used multivariate logistic regression to estimate associations between patient race and dependent
variables, and random effects models to estimate site-level contributions.
RESULTS Patients traveled a median 30 minutes (range 1–180) and waited a median 20 minutes (range 0–210) to see their provider. On
average, blacks and Hispanics reported longer travel and wait times compared with whites. Adjusting for HIV care site attenuated
this association. HIV care sites that provide services to a greater proportion of blacks and Hispanics may be more difficult
to access for all patients. The majority of patients rated provider communication favorably. Compared to whites, blacks reported
more positive experiences with provider communication.
CONCLUSIONS We observed racial disparities in patients’ experience of access to care but not in patient–provider communication. Disparities
were explained by poor access at minority-serving clinics. Efforts to make care more patient-centered for minority HIV-infected
patients should focus more on improving access to HIV care in minority communities than on improving cross-cultural patient–provider
interactions. 相似文献
68.
Justin Ng Nagesh Chopra Chirag Barbhaiya Tobias Reichlin Eyal Nof Koichi Nagashima Thomas Tadros Bruce A Koplan 《Journal of interventional cardiac electrophysiology》2014,39(3):281-285
Introduction
The need to detect impending implantable cardiac defibrillator (ICD) lead failure has grown. Automated sensing diagnostics have been developed for this reason. The sensing integrity counter (SIC) is one such oversensing diagnostic, which forms an integral part of the Medtronic? lead integrity alert (LIA) feature on implantable defibrillators. It records nonphysiologic short VV intervals (NPSVVIs). It is unclear whether SIC data derived from integrated bipolar (IBP) leads need to be interpreted differently when compared to true bipolar (TBP) leads. We hypothesized that IBP ICD leads by virtue of a larger “antennae” may generate more NPSVVIs on than TBP leads, leading to more false-positive SIC counts.Methods
Equal durations of remote monitoring records of 44 patients (mean age of 65.9?±?2.2 years, 52 % female) with IBP ICD leads and Medtronic (MDT) generators (IBP group) were compared with those of 44 randomly selected patients (64.0?±?2.2 years, 24 % female) who had TBP ICD leads and MDT generators (TBP group). Mean surveillance time, defined as the time over which the cumulative SIC count was acquired, was 614?±?44 days (TBP group) vs. 620?±?49 days (IBP group, p?=?ns). The mean time of follow-up following the first documented short VV interval was 115.2 months in the integrated bipolar group and 66.9 months in the true bipolar group. Leads on advisory were excluded from the study.Results
A total of 26/44 patients in the IBP group displayed NPSVVI compared to 11/44 patients in the TBP group (59 vs. 25 %; p?=?0.002, Fisher exact test). When adjusted for gender and lead age, the difference was still significant (p?=?0.008). When evaluating the clinical consequence of NPSVVI in this cohort, 3/11 TBP leads with NPSVVI of >0 were eventually extracted due to additional abnormalities vs. 0/26 IBP leads with NPSVVI (p?=?0.02, Fisher exact test). None of the IBP group patients with NPSVVI have developed inappropriate therapy from lead noise or a need for abandonment or extraction.Conclusion
Integrated bipolar ICD leads are more likely to have elevated SIC counts than true bipolar leads despite revealing no other evidence of lead failure. There does not appear to be a need for heightened surveillance in IBP leads with observed elevated SIC counts that have no other findings to suggest lead malfunction. 相似文献69.
Aviv Nof Ofer Amir Pavel Goldstein Sigal Zilcha-Mano 《Clinical psychology & psychotherapy》2021,28(4):807-817
Predicting the trajectories of alliance formation that the patient is likely to establish with the therapist during treatment, even before their first meeting, can help prevent the potentially harmful consequences of deterioration in alliance, such as poor outcome and premature dropout. The present study aimed to examine the ability of four pretreatment acoustic markers to predict the alliance that is likely to be formed in the course of treatment: F0 span, speech rate, pause proportion and jitter. Data from 560 observations of 38 patients were collected as part of an ongoing randomized clinical trial of short-term psychotherapy for major depressive disorder. The acoustic markers were measured using high-quality recordings at baseline, before the patient and therapist ever met or had any type of communication. A multilevel model was used to examine the ability of the four acoustic markers to predict the slopes of alliance formation in the course of treatment, all markers being introduced in the same model. The clinical utility of the acoustic markers was explored in two case studies. The model explained 22% of the variance in alliance formation. Higher levels of both jitter and pause proportion at baseline predicted less strengthening of the alliance in the course of treatment. The findings, which should be replicated in larger samples, suggest that much of the therapeutic alliance can be predicted based on the acoustic characteristics of the patient's voice in the first 3 min of their intake, before they even meet their therapist. 相似文献
70.
Emily B. Falk Luke W. Hyde Colter Mitchell Jessica Faul Richard Gonzalez Mary M. Heitzeg Daniel P. Keating Kenneth M. Langa Meghan E. Martz Julie Maslowsky Frederick J. Morrison Douglas C. Noll Megan E. Patrick Fabian T. Pfeffer Patricia A. Reuter-Lorenz Moriah E. Thomason Pamela Davis-Kean Christopher S. Monk John Schulenberg 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(44):17615-17622
The last decades of neuroscience research have produced immense progress in the methods available to understand brain structure and function. Social, cognitive, clinical, affective, economic, communication, and developmental neurosciences have begun to map the relationships between neuro-psychological processes and behavioral outcomes, yielding a new understanding of human behavior and promising interventions. However, a limitation of this fast moving research is that most findings are based on small samples of convenience. Furthermore, our understanding of individual differences may be distorted by unrepresentative samples, undermining findings regarding brain–behavior mechanisms. These limitations are issues that social demographers, epidemiologists, and other population scientists have tackled, with solutions that can be applied to neuroscience. By contrast, nearly all social science disciplines, including social demography, sociology, political science, economics, communication science, and psychology, make assumptions about processes that involve the brain, but have incorporated neural measures to differing, and often limited, degrees; many still treat the brain as a black box. In this article, we describe and promote a perspective—population neuroscience—that leverages interdisciplinary expertise to (i) emphasize the importance of sampling to more clearly define the relevant populations and sampling strategies needed when using neuroscience methods to address such questions; and (ii) deepen understanding of mechanisms within population science by providing insight regarding underlying neural mechanisms. Doing so will increase our confidence in the generalizability of the findings. We provide examples to illustrate the population neuroscience approach for specific types of research questions and discuss the potential for theoretical and applied advances from this approach across areas. 相似文献