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1.
Artigo em Inglês | MEDLINE | ID: mdl-32919411

RESUMO

Chronic alcohol use has important effects on the glutamate system. The metabotropic glutamate 5 (mGlu5) receptor has shown promise in preclinical models as a target to reduce drinking-related behaviors and cue-induced reinstatement, motivating human studies of mGlu5 receptor negative allosteric modulators. The goal of this work was to measure levels of mGlu5 receptor availability with positron emission tomography (PET) imaging using the mGlu5 receptor-specific radiotracer [18F]FPEB during early and extended alcohol abstinence. Subjects who met DSM-5 criteria for alcohol use disorder (AUD; n = 17) were admitted inpatient for the study duration. [18F]FPEB PET scans were acquired first during early abstinence (6 ± 4 days after last drink) and a second time during extended abstinence (n = 13; 27 ± 6 days after last drink). A single scan was acquired in healthy controls matched for sex and smoking status (n = 20). [18F]FPEB total volumes of distribution (VT) corrected for partial volume effects were measured using equilibrium analysis throughout the brain. A linear mixed model controlling for smoking status and sex identified significantly higher [18F]FPEB VT in AUD subjects at early abstinence compared to controls (F(1,32) = 7.23, p = 0.011). Post-hoc analyses revealed this effect to occur in cortical brain regions. No evidence for significant changes in [18F]FPEB VT over time were established. These findings provide human evidence consistent with a robust preclinical literature supporting mGlu5 receptor drugs as pharmacotherapies for AUD.

2.
J Affect Disord ; 277: 559-567, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32891062

RESUMO

BACKGROUND: Network analysis has become popular among PTSD researchers for studying causal structure or interrelationships among symptoms. However, some have noted that results do not seem to be consistent across studies. Preliminary evidence suggests that trauma type may be one source of variability. METHODS: The current study sought to examine the PTSD networks of veterans with combat versus non-combat index trauma. Participants included 944 veterans who completed the PTSD Checklist for DSM-5 at intake at two VA PTSD clinics. RESULTS: There were many similarities between the combat and non-combat trauma networks, including strong edges between symptoms that were theoretically related or similar (e.g., avoidance) and negative emotion being a highly central symptom. However, correlations of edge weights (0.509) and node centrality (0.418) across networks suggested moderate correspondence, and there appeared to be some differences associated with certain symptoms. Detachment was relatively more central and the connections of negative emotion with blame and lack of positive emotion with reckless behavior were stronger for veterans with combat-related index trauma. LIMITATIONS: The data were cross-sectional, which limits the ability to infer directional relationships between symptoms. In addition, the sample was likely not large enough to directly test for differences between networks via network comparison tests. CONCLUSIONS: Although there were many similarities, results also suggested some variability in PTSD networks associated with combat versus non-combat index trauma that could have implications for conceptualizing and treating PTSD among veterans.

3.
Gait Posture ; 82: 138-146, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32927220

RESUMO

BACKGROUND: Balance responses to perturbations often involve the arms in an attempt to either restore balance or protect against impact. Although a majority of research has been dedicated to understanding age-related changes in lower limb balance responses, there is a growing body of evidence supporting age-related changes in arm responses. This systematic review aimed to summarize differences in arm responses between older and younger adults under conditions requiring counterbalancing, reaching to grasping, and protection against impact. METHODS: Following a systematic review and critical appraisal of the literature, data regarding the arm response in studies comparing young and older adults was extracted. The resulting articles were also assessed for quality to determine risk of bias. RESULTS: Fifteen high quality studies were identified. The majority of these studies reported delayed onsets in muscle activation, differences in arm movement strategies, delayed movement timing, increased impact forces, and greater grasp errors in older compared to young adults. These differences were also identified under varied visual and cognitive conditions. CONCLUSIONS: The studies included in this review demonstrate age-related differences in arm responses regardless of the direction and nature of the perturbation. These differences could provide insight into developing more targeted rehabilitation and fall prevention strategies. More research is needed to assess whether the identified age-related differences are a necessary compensation or a contributory factor to balance impairments and fall risk in older adults.

4.
Toxicol In Vitro ; 69: 104995, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32891721

RESUMO

The ISO 10993 standards on biocompatibility assessment of medical devices discourage the use of animal tests when reliable and validated in vitro methods are available. A round robin validation study of in vitro reconstructed human epidermis (RhE) assays was performed as potential replacements for rabbit skin irritation testing. The RhE assays were able to accurately identify strong irritants in dilute medical device extracts. However, there was some uncertainty about whether RhE tissues accurately predicted the results of the rabbit skin patch or intracutaneous irritation test. To address that question, this paper presents in vivo data from the round robin and subsequent follow-up studies. The follow-up studies included simultaneous in vitro RhE model and in vivo testing of round robin polymer samples and the results of dual in vitro/in vivo testing of currently marketed medical device components/materials. Our results show for the first time that for both pure chemicals and medical device extracts the intracutaneous rabbit test is more sensitive to detect irritant activity than the rabbit skin patch test. The studies showed that the RhE models produced results that were essentially equivalent to those from the intracutaneous rabbit skin irritation test. Therefore, it is concluded that RhE in vitro models are acceptable replacements for the in vivo rabbit intracutaneous irritation test for evaluating the irritant potential of medical devices.

5.
Plast Reconstr Surg Glob Open ; 8(7): e2892, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32802635

RESUMO

Matching into integrated plastic surgery residency is highly competitive. Applicants to these programs are among the most accomplished graduating medical students, consistently demonstrating some of the highest United States Medical Licensing Examination scores, mean numbers of research publications, and rates of Alpha Omega Alpha Honor Medical Society membership. The applicant review process requires programs to rely on a number of objective and subjective factors to determine which of these qualified applicants have the most potential for success. We outline these factors, discuss their correlation with resident performance, and provide our institution's applicant review process both for applicants hoping to optimize their applications for success in the National Resident Matching Program and for program faculty hoping to optimize their resident selection process.

6.
mSystems ; 5(4)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32788409

RESUMO

New therapies are necessary to combat increasingly antibiotic-resistant bacterial pathogens. We have developed a technology platform of computational, molecular biology, and microbiology tools which together enable on-demand production of phages that target virtually any given bacterial isolate. Two complementary computational tools that identify and precisely map prophages and other integrative genetic elements in bacterial genomes are used to identify prophage-laden bacteria that are close relatives of the target strain. Phage genomes are engineered to disable lysogeny, through use of long amplicon PCR and Gibson assembly. Finally, the engineered phage genomes are introduced into host bacteria for phage production. As an initial demonstration, we used this approach to produce a phage cocktail against the opportunistic pathogen Pseudomonas aeruginosa PAO1. Two prophage-laden P. aeruginosa strains closely related to PAO1 were identified, ATCC 39324 and ATCC 27853. Deep sequencing revealed that mitomycin C treatment of these strains induced seven phages that grow on P. aeruginosa PAO1. The most diverse five phages were engineered for nonlysogeny by deleting the integrase gene (int), which is readily identifiable and typically conveniently located at one end of the prophage. The Δint phages, individually and in cocktails, killed P. aeruginosa PAO1 in liquid culture as well as in a waxworm (Galleria mellonella) model of infection.IMPORTANCE The antibiotic resistance crisis has led to renewed interest in phage therapy as an alternative means of treating infection. However, conventional methods for isolating pathogen-specific phage are slow, labor-intensive, and frequently unsuccessful. We have demonstrated that computationally identified prophages carried by near-neighbor bacteria can serve as starting material for production of engineered phages that kill the target pathogen. Our approach and technology platform offer new opportunity for rapid development of phage therapies against most, if not all, bacterial pathogens, a foundational advance for use of phage in treating infectious disease.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32860130

RESUMO

We conducted a meta-analysis of preclinical studies that tested left ventricular assist device (LVAD) therapy for reducing myocardial infarct size in experimental acute myocardial infarction (AMI). Twenty-six articles were included with a total of 488 experimental animal subjects. The meta-analysis showed that infarct size was significantly decreased by LVAD support compared to control animals (SDM, - 2.19; 95% CI, - 2.70 to - 1.69; P < 0.001). The meta-regression analysis demonstrated a high degree of heterogeneity associated with time from coronary artery occlusion to LVAD support, which correlated positively with infarct size. Subgroup analysis suggested smaller infarct size in LVAD therapies that withdrew blood from left heart than those from right heart. The proportion of left ventricular support relative to total cardiac output was positively correlated with infarct size reduction in Impella studies. Thus, early initiation of LVAD after ischemia and effective left ventricular venting may be important factors to reduce infarct size in AMI.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32824096

RESUMO

We have a limited understanding of the socioenvironmental factors associated with participation in physical activity among school-aged children with autism spectrum disorder (ASD), particularly regarding how the school environment may influence their participation. Using the International Classification of Functioning, Disability and Health (ICF) as a framework, this study examined the effect of body functions and structure, activity, and personal factors on in-school physical activity; and whether in-school physical activity, considered a socioenvironmental factor, is associated with out-of-school physical activity (i.e., participation) among elementary school-aged children (6-13 years of age) with ASD. Parents of 202 children with ASD (78.2% boys; Mage = 9.4 years) completed an online survey, as part of a larger study, to assess their child's functioning and physical activity in- and out-of-school. Results indicated that the majority of children (85.1%) did not meet physical activity guidelines. In-school physical activities significantly predicted out-of-school physical activities including leisure-time moderate-to-vigorous physical activity (R2 = 0.27, F(10,154) = 5.67, p < 0.001) and meeting the physical activity guidelines (R2 = 0.23, Χ2 (10) = 31.9, p < 0.001). These findings underscore the importance of supporting children with ASD to be physically active in school, which may impact physical activity levels out-of-school.

9.
Disabil Health J ; : 100980, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32830082

RESUMO

BACKGROUND: Canada's 24-Hour Movement Guidelines for Children and Youth provide daily recommendations for physical activity (PA), screen time, and sleep for optimal health. The appropriateness of such guidelines for youth with disabilities remains unknown. OBJECTIVE: To cross-sectionally examine the 24-h movement behaviours and guideline adherence in youth (ages 12-21 years) with physical and sensory disabilities. METHODS: 54 youth with physical and sensory disabilities completed two, 24-h recalls to assess PA, sedentary behaviour, and sleep. Descriptive statistics were used to analyze behavioural patterns and guideline adherence. Gender and age differences were tested using analyses of variance and logistic regressions. RESULTS: 55.5%, 13.0%, and 53.7% of the sample met the individual guidelines for PA, sedentary behaviour, and sleep, respectively. 3.7% of the sample met all three movement guidelines. No significant gender or age differences in guideline achievement were found. Over a 24-h period, youth spent 77 (59) minutes engaging in moderate to vigorous PA, 252 (120) minutes engaging in sedentary activity, and 546 (90) minutes sleeping. Boys reported significantly more time (adjusted Mdifference = 11 min) playing passive video games than girls. CONCLUSION: Overall, our sample of youth with physical and sensory disabilities falls far short of meeting the Canadian 24-Hour Movement Guidelines for Children and Youth. The low proportion of youths' time spent engaging in sport and active play is concerning, highlighting the importance of creating access to these types of PA experiences for this population. Future population-based research is needed among children and youth with all types of disabilities to build an evidence-base of their movement behaviours.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32804714

RESUMO

Individuals with stroke often experience contralesional and ipsilesional arm motor deficits. OBJECTIVES: Compare fine and gross motor hand dexterity of the ipsilesional hand post-stroke with controls, normative values, and the contralesional hand. DESIGN: Data were collected from right-handed individuals with chronic stroke (n = 20), age/sex matched controls (n = 10), and normative values (n = 20) performing the Nine Hole Peg Test and the Box and Blocks Test. RESULTS: Individuals with stroke demonstrated poorer performance with the ipsilesional arm relative to both the control group (mean difference [95% CI]: Nine Hole Peg Test (s): 3.4 [-0.5, 7.3]; Box and Blocks Test (# blocks): -12.3 [-20.3, -4.2]) and normative values (mean difference [95% CI]: Nine Hole Peg Test (s): 6.5 [4.0, 9.1]; Box and Blocks Test (# blocks): -15.3 [-20.1, -10.5]). Ipsilesional arm performance was significantly better than performance with the contralesional arm (mean difference [95% CI]: Nine Hole Peg Test (s): -9.4 [-20.2, 1.4]; Box and Blocks Test (# blocks): 33.2 [20.9, 45.5]). CONCLUSION: These findings identify residual deficits in fine and gross dexterity of the ipsilesional hand in commonly used outcome measures of hand manipulation among individuals with chronic stroke. Possible underlying mechanisms and clinical relevance are discussed.

11.
Brain Sci ; 10(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825342

RESUMO

The objective of this study was to examine age-related differences in arm and trunk responses during first and repeated step induced balance perturbations. Young and older adults received 10 trials of unpredictable lateral platform translations. Outcomes included maximum arm and trunk displacement within 1 s of perturbation and at first foot lift off (FFLO), arm and neck muscle activity as recorded using electromyography (EMG), initial step type, balance confidence, and percentage of harness-assisted trials. Compared to young adults, older adults demonstrated greater arm and trunk angular displacements during the first trial, which were present at FFLO and negatively associated with balance confidence. Unlike young adults, recovery steps in older adults were directed towards the fall with a narrowed base of support. Over repeated trials, rapid habituation of first-trial responses of bilateral arm and trunk displacement and EMG amplitude was demonstrated in young adults, but was absent or limited in older adults. Older adults also relied more on harness assistance during balance recovery. Exaggerated arm and trunk responses to sudden lateral balance perturbations in older adults appear to influence step type and balance recovery. Associations of these persistently amplified movements with an increased reliance on harness assistance suggest that training to reduce these deficits could have positive effects in older adults with and without neurological disorders.

12.
Ir Med J ; 113(6): 93, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32816428

RESUMO

Introduction The number of fragility hip fractures (>60 years) are estimated to triple/quadruple by 2050. It is estimated that the prevalence of patient's contralateral hip fractures (HF2s) will increase also. Methods Single hospital, Retrospective review, 2013-2017, Radiograph review, n = 822. Results Management of patient's 2nd hip fractures accounted for 10.5% of all hip fracture surgeries. ~50% occurred within 3 years of the 1st hip fracture. There was no statistically significant difference in discharge destination, length-of-stay or mortality between the HF1 and HF2 cohorts. Discussion Patients with HF2s comprised a significant and stable proportion of all hip fractures treated. We advocate for the provision of a Fracture Liaison Service in each of the 16 hip fracture operating hospitals in Ireland to optimise the secondary prevention of hip fractures.

13.
J Nucl Med ; 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680926

RESUMO

The positron emission tomography (PET) ligand 11C-PBR28 binds to the 18kDa translocator protein (TSPO), a biomarker of glia. In clinical studies of TSPO, the ligand total distribution volume, VT, is frequently the reported outcome measure. Since VT is the sum of the ligand specific (VS) and non-displaceable binding (VND), differences in VND across subjects and groups will have an impact on VT. Methods: Here, we used a recently developed method for simultaneous estimation of VND (SIME) to disentangle contributions from VND and VS. Data from four previously published 11C-PBR28 PET studies were included: (i) before and after a lipopolysaccharide challenge (8 subjects), (ii) in alcohol use disorder (14 patients, 15 controls), (iii) in first-episode psychosis (16 patients, 16 controls), and (iv) in Parkinson's disease (16 patients, 16 controls). In each dataset, regional VT estimates were obtained with a standard two-tissue compartment model, and brain-wide VND was estimated with SIME. VS was then calculated as VT-VND. VND and VS were then compared across groups, within each dataset. Results: A lower VND was found for individuals with alcohol use disorder (34%, P = 0.00084) and Parkinson's disease (34%, P = 0.0032), when compared to their corresponding controls. We found no difference in VND between first-episode psychosis patients and their controls, and the administration of lipopolysaccharide did not change VND. Conclusion: Our findings suggest that in TSPO PET studies, non-displaceable binding can differ between patient groups and conditions and should therefore be taken into account.

14.
J Am Med Dir Assoc ; 2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32636169

RESUMO

OBJECTIVES: Capacity for safe and independent living (SAIL) refers to an individual's ability to solve problems associated with everyday life and perform activities necessary for living independently. Little guidance exists on the assessment of capacity for SAIL among nursing home residents. As a result, capacity for SAIL is not fully considered in the development of discharge plans to ensure safety and independence in the community. We reasoned that this problem could be addressed with the Making and Executing Decisions for Safe and Independent Living (MEDSAIL) tool, developed to screen for capacity for SAIL among community-dwelling older adults. In this report, we describe findings on the validity of the MEDSAIL when used with nursing home residents. DESIGN: Prospective cross-sectional pilot study. SETTING AND PARTICIPANTS: Twenty-four residents of a Veterans Health Affairs Community Living Center (CLC; nursing home); exclusion criteria were cognitive impairment too severe to complete the protocol, diagnosis of serious mental illness or developmental disability, inability to hear, or inability to communicate verbally. METHODS: Participants completed 2 assessments: the MEDSAIL interview administered by a research assistant and the criterion standard capacity interview administered by a geriatric psychiatrist. We examined internal consistency, divergent validity, and criterion-based validity. RESULTS: Five of 7 MEDSAIL scenarios approximated acceptable levels of internal consistency (α >0.70). MEDSAIL scores were highly positively correlated with criterion standard capacity determination (0.88, P = .001), and the Wilcoxon rank-sum test statistic for the 2 assessments was also statistically significant (P = .001). CONCLUSIONS AND IMPLICATIONS: MEDSAIL has promise as a user-friendly brief screening tool for use by nursing home staff to understand resident capacity for SAIL. This information can be used in the development of discharge plans to keep the resident safe and independent in the community. In addition, tailoring the MEDSAIL scenarios specifically to the nursing home setting may further enhance the tool's validity and utility in this new application.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32617555

RESUMO

Balance impairment and falls are among the most prevalent and morbid conditions affecting older adults. A critical contributor to balance and gait function is the vestibular system; however, there remain substantial knowledge gaps regarding age-related vestibular loss and its contribution to balance impairment and falls in older adults. Given these knowledge gaps, the National Institute on Aging and the National Institute on Deafness and Other Communication Disorders convened a multidisciplinary workshop in April 2019 that brought together experts from a wide array of disciplines, such as vestibular physiology, neuroscience, movement science, rehabilitation, and geriatrics. The goal of the workshop was to identify key knowledge gaps on vestibular function and balance control in older adults and develop a research agenda to make substantial advancements in the field. This article provides a report of the proceedings of this workshop. Three key questions emerged from the workshop, specifically: (i) How does aging impact vestibular function?; (ii) How do we know what is the contribution of age-related vestibular impairment to an older adult's balance problem?; and more broadly, (iii) Can we develop a nosology of balance impairments in older adults that can guide clinical practice? For each of these key questions, the current knowledge is reviewed, and the critical knowledge gaps and research strategies to address them are discussed. This document outlines an ambitious 5- to 10-year research agenda for increasing knowledge related to vestibular impairment and balance control in older adults, with the ultimate goal of linking this knowledge to more effective treatment.

16.
Parasitol Res ; 119(9): 2955-2963, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32647992

RESUMO

Equine piroplasmosis (EP) is an infectious, tick-borne disease caused by the hemoprotozoan parasites, Theileria equi, Babesia caballi, and a recently reported new species, T. haneyi. Infections by these apicomplexan parasites limit performance and cause economic losses for the horse industry. Equine piroplasmosis is widespread in the northern regions of Nigeria, where an increasing portion of the animal population is composed of horses. This disease has remained epidemiologically challenging, especially as the movement of horses increases across Nigeria. In this study, blood samples from 300 horses were collected in three states of northwestern Nigeria. The presence of piroplasms was screened by nested PCR targeting 18S rDNA and positive samples were analyzed using species-specific-nested PCR-targeting genes including ema1 (T. equi), rap1 (B. caballi), and a gene coding a protein of unknown function (T. haneyi). Species-specific-nPCR results demonstrated that the prevalence of T. equi was 13.0% (39/300), B. caballi was 3.3% (10/300) and T. haneyi was 2.7% (8/300). Mixed infections with T. equi and B. caballi was 2.7% (8/300) while T. equi, B. caballi, and T. haneyi multiple infection prevalence was 0.6% (2/300). We used 18S rDNA sequences to determine close relationships between T. equi by phylogenetic analysis and demonstrated that among 57 sequences of Theileria parasites, 28 samples belonged to clade A (49%), 13 samples were found to be clade C (22%), and 16 were clade D (28%). These results demonstrate the genetic diversity of T. equi circulating in horses from Nigeria.

17.
Hum Reprod ; 35(8): 1875-1888, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32614049

RESUMO

STUDY QUESTION: Which transcriptomic alterations in mid-luteal endometrial scratch biopsies, taken prior to the assisted reproductive treatment (ART) treatment cycle are associated with unsuccessful pregnancy? SUMMARY ANSWER: Dysregulated interleukin-17 (IL-17) pathway components are demonstrated in women who fail to become pregnant after ART. WHAT IS KNOWN ALREADY: Implantation failure is now recognised as a critical factor in unexplained infertility and may be an important component of failed ART. STUDY DESIGN, SIZE, DURATION: Using a prospective longitudinal study design, 29 nulliparous women with unexplained infertility undergoing ART were recruited between October 2016 and February 2018. Mid-luteal stage endometrium and matched serum samples were collected, and patients underwent a single embryo transfer in the subsequent cycle. RNA-seq analysis of endometrial biopsies was performed on the discovery cohort (n = 20). PARTICIPANTS/MATERIALS, SETTING, METHODS: Gene set enrichment analysis of the differentially expressed genes (DEGs) was performed. Endometrium and serum were then prepared for IL-17A analysis by ELISA. MAIN RESULTS AND THE ROLE OF CHANCE: There were 204 differentially expressed protein-coding genes identified in tissue from women who became pregnant (n = 9) compared with tissue from women who failed to become pregnant (n = 11) (false discovery rate; P < 0.05). Of the 204 DEGs, 166 were decreased while 38 were increased in the pregnant compared to the non-pregnant groups. Gene set enrichment analysis of the DEGs identified an over-representation of IL-17 and Pl3K-Akt signalling pathways. All the DEGs within the IL-17 signalling pathway (MMP3, MMP1, IL1ß, LCN2, S100A9 and FOSL1) demonstrated decreased expression in the pregnant group. Serum IL-17 protein levels were increased in the non-pregnant discovery cohort (n = 11) and these findings were confirmed a validation cohort (n = 9). LIMITATIONS, REASONS FOR CAUTION: Limitations of our study include the cohort size and the lack of aneuploidy data for the embryos; however, all embryos transferred were single good or top-quality blastocysts. WIDER IMPLICATIONS OF THE FINDINGS: These findings demonstrate dysregulated IL-17 pathway components in women who fail to become pregnant after ART. Elevated serum levels of the pro-inflammatory cytokine IL-17 may predict failure of ART in women with unexplained infertility. Future trials of anti-IL-17 therapies in this cohort warrant further investigation. STUDY FUNDING/COMPETING INTEREST(S): Funding from the UCD Wellcome Institutional Strategic Support Fund, which was financed jointly by University College Dublin and the SFI-HRB-Wellcome Biomedical Research Partnership (ref 204844/Z/16/Z), is acknowledged. The authors have no competing interests. TRIAL REGISTRATION NUMBER: NA.

18.
Cell Rep ; 31(13): 107827, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32610128

RESUMO

The PD-1 pathway regulates dysfunctional T cells in chronic infection and cancer, but the role of this pathway during acute infection remains less clear. Here, we demonstrate that PD-1 signals are needed for optimal memory. Mice deficient in the PD-1 pathway exhibit impaired CD8+ T cell memory following acute influenza infection, including reduced virus-specific CD8+ T cell numbers and compromised recall responses. PD-1 blockade during priming leads to similar differences early post-infection but without the defect in memory formation, suggesting that timing and/or duration of PD-1 blockade could be tailored to modulate host responses. Our studies reveal a role for PD-1 as an integrator of CD8+ T cell signals that promotes CD8+ T cell memory formation and suggest PD-1 continues to fine-tune CD8+ T cells after they migrate into non-lymphoid tissues. These findings have important implications for PD-1-based immunotherapy, in which PD-1 inhibition may influence memory responses in patients.

19.
Adapt Phys Activ Q ; : 1-19, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541083

RESUMO

Videoconferencing is a novel method for overcoming time and transportation barriers to leisure-time physical activity (LTPA) interventions. This study examined the feasibility of a group videoconference intervention on LTPA self-regulatory skills training in a sample of nine adults with spinal cord injury (SCI). Session implementation checklists and self-report surveys were administered during four weekly sessions to assess intervention management, group processes, intervention resources, and initial efficacy. Attendance rate was high (91.7%), and the average weekly session duration was 79.6 min. Participants reported high ratings of group cohesion, facilitator collaboration, session content comprehension, and ease in operating the videoconference platform. Knowledge sharing among the group ranged from 18 to 58 exchanges per session, demonstrating learning and group cohesion. LTPA frequency increased among 44% of participants, and 22% of participants achieved the SCI-specific aerobic guidelines. Overall, group videoconferencing holds promise for LTPA support among adults with SCI. Long-term research is warranted to test LTPA self-regulatory and behavioral effects.

20.
Autism ; : 1362361320922658, 2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32476438

RESUMO

LAY ABSTRACT: Children and youth with autism spectrum disorder engage in less physical activity than neurotypically developing peers. This may be due to factors associated with autism spectrum disorder at the individual and environmental level that can make physical activity participation more challenging. Parent support is a known determinant of physical activity among children and youth; however, limited research has explored the relationship between parent physical activity support behaviour and child physical activity behaviour within the autism spectrum disorder population. The purpose of this study was to examine the relationship between parent physical activity support behaviour and physical activity levels of children and youth with autism spectrum disorder. Parents (n = 201) of school-aged children and youth with autism spectrum disorder completed measures of parent physical activity support (intentions, behavioural regulation, support behaviour), as well as their child's physical activity behaviour. The results showed that parent's intentions to provide physical activity support were associated with their support behaviour for their child's physical activity (e.g. encouragement, being active together). Parents who followed through with their intentions to provide support reported using behavioural regulation strategies such as goal setting and planning more often. Finally, the results showed parent physical activity support behaviour was positively associated with child physical activity behaviour. Findings suggest parents play an instrumental role in the physical activity behaviour of children and youth with autism spectrum disorder. Family-level interventions targeting parents' behavioural regulation strategies to provide physical activity support may be an effective strategy to increase physical activity in children and youth with autism spectrum disorder.

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