Effects of a laboratory-based aerobic exercise intervention on brain volume and cardiovascular health markers: protocol for a randomised clinical trial

INTRODUCTION

Physical activity (PA) has beneficial effects on brain health and cardiovascular disease (CVD) risk. Yet, we know little about whether PA-induced changes to physiological mediators of CVD risk influence brain health and whether benefits to brain health may also explain PA-induced improvements to CVD risk. This study combines neurobiological and peripheral physiological methods in the context of a randomised clinical trial to better understand the links between exercise, brain health and CVD risk.

METHODS AND ANALYSIS

In this 12-month trial, 130 healthy individuals between the ages of 26 and 58 will be randomly assigned to either: (1) moderate-intensity aerobic PA for 150 min/week or (2) a health information control group. Cardiovascular, neuroimaging and PA measurements will occur for both groups before and after the intervention. Primary outcomes include changes in (1) brain structural areas (ie, hippocampal volume); (2) systolic blood pressure (SBP) responses to functional MRI cognitive stressor tasks and (3) heart rate variability. The main secondary outcomes include changes in (1) brain activity, resting state connectivity, cortical thickness and cortical volume; (2) daily life SBP stress reactivity; (3) negative and positive affect; (4) baroreflex sensitivity; (5) pulse wave velocity; (6) endothelial function and (7) daily life positive and negative affect. Our results are expected to have both mechanistic and public health implications regarding brain-body interactions in the context of cardiovascular health.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the University of Pittsburgh Institutional Review Board (IRB ID: 19020218). This study will comply with the NIH Data Sharing Policy and Policy on the Dissemination of NIH-Funded Clinical Trial Information and the Clinical Trials Registration and Results Information Submission rule.

TRIAL REGISTRATION NUMBER

NCT03841669.

Bias-corrected and doubly robust inference for the three-level longitudinal cluster-randomized trials with missing continuous outcomes and small number of clusters: Simulation study and application to a study for adults with serious mental illnesses

Longitudinal cluster-randomized designs have been popular tools for comparative effective research in clinical trials. The methodologies for the three-level hierarchical design with longitudinal outcomes need to be better understood under more pragmatic settings; that is, with a small number of clusters, heterogeneous cluster sizes, and missing outcomes. Generalized estimating equations (GEEs) have been frequently used when the distribution of data and the correlation model are unknown. Standard GEEs lead to bias and an inflated type I error rate due to the small number of available clinics and non-completely random missing data in longitudinal outcomes. We evaluate the performance of inverse probability weighted (IPW) estimating equations, with and without augmentation, for two types of missing data in continuous outcomes and individual-level treatment allocation mechanisms combined with two bias-corrected variance estimators. Our intensive simulation results suggest that the proposed augmented IPW method with bias-corrected variance estimation successfully prevents the inflation of false positive findings and improves efficiency when the number of clinics is small, with moderate to severe missing outcomes. Our findings are expected to aid researchers in choosing appropriate analysis methods for three-level longitudinal cluster-randomized designs. The proposed approaches were applied to analyze data from a longitudinal cluster-randomized clinical trial involving adults with serious mental illnesses.

IDENTIFICATION OF IMMUNE RESPONSE COMBINATIONS ASSOCIATED WITH HETEROGENEOUS INFECTION RISK IN THE IMMUNE CORRELATES ANALYSIS OF HIV VACCINE STUDIES

In HIV vaccine/prevention research, probing into the vaccine-induced immune responses that can help predict the risk of HIV infection provides valuable information for the development of vaccine regimens. Previous correlate analysis of the Thai vaccine trial aided the discovery of interesting immune correlates related to the risk of developing an HIV infection. The present study aimed to identify the combinations of immune responses associated with the heterogeneous infection risk. We explored a "change-plane" via combination of a subset of immune responses that could help separate vaccine recipients into two heterogeneous subgroups in terms of the association between immune responses and the risk of developing infection. Additionally, we developed a new variable selection algorithm through a penalized likelihood approach to investigate a parsimonious marker combination for the change-plane. The resulting marker combinations can serve as candidate correlates of protection and can be used for predicting the protective effect of the vaccine against HIV infection. The application of the proposed statistical approach to the Thai trial has been presented, wherein the marker combinations were explored among several immune responses and antigens.

Stress analysis of self-tightness metal sealing against ultrahigh pressure medium

Stress is one of the most important factors in metal-to-metal sealing. In this paper, two methods (theoretical and empirical) were adopted to calculate the normal stress of the brass sealing surfaces against different ultrahigh pressure liquid. The theoretical formula was derived in terms of force balance, and the empirical formula was obtained by polynomial curve fitting, which the fitted data were from simulated results; besides, the results calculated using the empirical formula agree well with the results by theoretical formula. Meanwhile, the equivalent stresses of the brass seal, normal stress and contact stress on the brass seal surfaces were simulated by finite element method, and the simulated results indicated these stresses are increased with the increase of liquid pressure, and the maximum stresses always appear on the tip of the brass seal.

Cardiorespiratory fitness levels and body mass index of pre-adolescent children and older adults during the COVID-19 pandemic

Introduction

The social and behavioral effects of the COVID-19 pandemic have impacted the health and physiology of most people, including those never diagnosed with COVID-19. While the impact of the pandemic has been felt across the lifespan, its effects on cardiorespiratory fitness (commonly considered a reflection of total body health) of older adults and children may be particularly profound due to social distancing and stay-at-home advisories, as well as the closure of sport facilities and non-essential businesses. The objective of this investigation was to leverage baseline data from two ongoing clinical trials to determine if cardiorespiratory fitness and body mass index were different during COVID-19 relative to before COVID-19 in older adults and children.

Methods

Healthy older individuals (N = 593; 65-80 years) and 200 typically developing children (8-10 years) completed a graded maximal exercise test and had their height and weight measured.

Results

Results revealed that older adults and children tested during COVID-19 had significantly lower cardiorespiratory fitness levels than those tested before COVID-19 shutdowns (older adults: 30% lower; children: 53% lower; p's ≤ 0.001). In addition, older adults and children tested during COVID-19 had significantly higher BMI (older adults: 31.34 ± 0.57 kg/m2, p = 0.004; children: 19.27 ± 0.44 kg/m2, p = 0.05) than those tested before COVID-19 shutdowns (older adults: 29.51 ± 0.26 kg/m2, children: 18.13 ± 0.35 kg/m2). However, these differences in BMI did not remain significant when controlling for cardiorespiratory fitness.

Discussion

Results from this investigation indicate that the COVID-19 pandemic, and behavior changes taken to reduce potential exposure, may have led to lower cardiorespiratory fitness levels in older adults and children, as well as higher body mass index. These findings provide relevant public health information as lower cardiorespiratory fitness levels and higher body mass indexes recorded during the pandemic could have far-reaching and protracted health consequences. Public health guidance is needed to encourage physical activity to maintain cardiorespiratory fitness and healthy body composition.

Clinical trial registration

Older adults: https://clinicaltrials.gov/ct2/show/NCT02875301, identifier: NCT02875301; Children: https://clinicaltrials.gov/ct2/show/NCT03592238, identifier: NCT03592238.

Hyponatremia and in-hospital outcomes of patients admitted for heart failure: analysis of the national inpatient sample

Background

Hyponatremia serves as a well established predictor of mortality for advanced heart failure (1). The aim of this study is to reassess the association between hyponatremia and in-hospital outcomes in patients with acute decompensated heart failure (ADHF) by using a nationally representative sample.

Methods

We queried the National Inpatient Sample (NIS) database collected between 2016 and 2018 to identify patients with a primary diagnosis of HF and stratified the cohort on the basis of presence or absence of hyponatremia. The outcomes of interest included in-hospital mortality, common associated complications and usage of circulatory support.

Results

Among 727,629 hospital admissions for HF, 72,824 (10%) of them had an additional diagnosis of hyponatremia. The hyponatremia cohort appeared similar in age and had similar rates of Charlson comorbidity index greater than 4 (71 years vs 72 years and 33% vs 35%, respectively) compared to the non-hyponatremia cohort. The comorbidities more prevalent in patients with hyponatremia included: hypothyroidism (17% vs 21%, p<0.001), liver disease (4% vs 11%, p<0.001) and anemia (31% vs 42, p<0.001). By contrast, dyslipidemia, chronic obstructive pulmonary disease, chronic kidney disease, hypertension, diabetes mellitus, obesity, smoking status and supplemental oxygen use were comparable in both groups. ADHF patients with hyponatremia did not have higher odds of in-hospital mortality (aOR: 1.08, 95% CI: 0.98–1.19, p=0.138) when adjusted for comorbidities. Nevertheless, patients with hyponatremia had an adjusted increase in mean hospital charges of 14,731 US$ (95% CI: 11065–18397, p<0.001), length of stay by 2.6 days (95% CI: 2.5–2.8, p<0.001), usage of intra-aortic balloon pump (aOR: 1.97, 95% CI: 1.50–2.59, p<0.001) and left ventricular assist device (aOR: 2.21, 95% CI: 1.639–2.98, p<0.001), and higher incidence of acute renal failure (aOR: 1.13, 95% CI: 1.08–1.189, p<0.001) and cardiogenic shock (aOR: 1.58, 95% CI: 1.42–1.76, p<0.001) in comparison to patients without hyponatremia.

Conclusion

Multiple clinical variables excluded in the NIS dataset could have impacted the primary outcome. Clinicians who observe hyponatremia in ADHF patients should stay wary of potential side effects and maintain a low threshold to escalate care.

Funding Acknowledgement

Type of funding sources: None.

The relationship between fat mass and obesity associated gene polymorphism rs9939609 and resting cerebral blood flow in a midlife sample with overweight and obesity

Background

The single nucleotide polymorphism (SNP) rs9939609 in the fat mass and obesity associated fat mass and obesity associated gene (FTO) gene has been linked with increased BMI in adults. Higher BMI has been associated with poor brain health and may exert deleterious effects on neurocognitive health through cerebral hypoperfusion. However, it is unclear if there is a relationship between the FTO genotype and cerebral perfusion, or whether FTO genotype moderates the effects of weight loss on cerebral perfusion. Using data from a randomized controlled behavioral weight loss trial in adults with overweight and obesity, we tested (1) whether carriers of the A allele for FTO rs9939609 demonstrate different patterns of resting cerebral blood flow (rCBF) compared to T carriers, and (2) whether the FTO genotype moderates the effects of weight loss on rCBF. We hypothesized that carriers of the A allele would exhibit lower resting CBF in frontal brain areas compared to T/T homozygotes at baseline, and that intervention-induced weight loss may partially remediate these differences.

Methods and results

One hundred and five adults (75.2% female, mean age 44.9 years) with overweight or obesity were included in the analyses. These participants represent a subsample of participants in a larger randomized controlled trial (NCT01500356). A resting pseudo-continuous arterial spin labeling (pCASL) scan was acquired to examine rCBF. Age, sex, and BMI were included as covariates. At baseline, A carriers had greater rCBF in a diffuse cluster extending into the brainstem, motor cortex, and occipital lobe, but lower perfusion in the temporal lobe. We found no evidence that FTO moderated the effect of the intervention group assignment on rCBF changes.

Conclusion

Overall, these results indicate that (a) individual variation in rCBF within a sample with overweight and obesity may be attributed to a common FTO variant, but (b) a weight loss intervention is effective at increasing rCBF, regardless of FTO genotype.

Aerobic exercise improves episodic memory in late adulthood: a systematic review and meta-analysis

Background

Aerobic exercise remains one of the most promising approaches for enhancing cognitive function in late adulthood, yet its potential positive effects on episodic memory remain poorly understood and a matter of intense debate. Prior meta-analyses have reported minimal improvements in episodic memory following aerobic exercise but have been limited by restrictive inclusion criteria and infrequent examination of exercise parameters.

Methods

We conducted a meta-analysis of randomized controlled trials to determine if aerobic exercise influences episodic memory in late adulthood (M = 70.82 years) and examine possible moderators. Thirty-six studies met inclusion criteria, representing data from 2750 participants.

Results

Here we show that aerobic exercise interventions are effective at improving episodic memory (Hedges'g = 0.28; p = 0.002). Subgroup analyses revealed a moderating effect of age (p = 0.027), with a significant effect for studies with a mean age between 55-68 but not 69-85. Mixed-effects analyses demonstrated a positive effect on episodic memory among studies with a high percentage of females (65-100%), participants with normal cognition, studies reporting intensity, studies with a no-contact or nonaerobic physical activity control group, and studies prescribing >3900 total minutes of activity (range 540-8190 min).

Conclusions

Aerobic exercise positively influences episodic memory among adults ≥55 years without dementia, with larger effects observed among various sample and intervention characteristics-the clearest moderator being age. These results could have far-reaching clinical and public health relevance, highlighting aerobic exercise as an accessible, non-pharmaceutical intervention to improve episodic memory in late adulthood.

Phase I trial combining chemokine-targeting with loco-regional chemo-immunotherapy for recurrent, platinum-sensitive ovarian cancer shows induction of CXCR3 ligands and markers of type 1 immunity

BACKGROUND

Increased prevalence of cytotoxic T lymphocytes (CTL) in the tumor microenvironment (TME) predicts positive outcomes in patients with epithelial ovarian cancer (EOC), while the regulatory Treg cells predict poor outcomes. Guided by the synergistic activity of TLR3 ligands, interferon-a (IFNa) and cyclooxygenase-2 (COX-2) blockers in selectively enhancing CTL-attractants but suppressing Treg-attractants, we tested a novel intraperitoneal (IP) chemo-immunotherapy combination, to assess its tolerability and TME-modulatory impact in patients with recurrent EOC.

METHODS

Twelve patients were enrolled in phase I portion of the trial NCT02432378, and treated with IP cisplatin, IP rintatolimod (dsRNA, TLR3 ligand) and oral celecoxib (COX-2 blocker). Patients in cohorts 2, 3 and 4 also received IP IFNa at 2, 6 and 18 million units (MU), respectively. Primary objectives were to evaluate safety, identify phase 2 recommended dose (P2RD) and characterize changes in the immune TME. Peritoneal resident cells and IP wash fluid were profiled via NanoString and Meso Scale Discovery (MSD) multiplex assay, respectively.

RESULTS

The P2RD of IFNa was 6 MU. Median progression-free and overall survival were 8.4 and 30 months, respectively. Longitudinal sampling of the peritoneal cavity via IP washes demonstrated local upregulation of interferon-stimulated genes (ISG), including CTL-attracting chemokines (CXCL-9, -10, -11), MHC I/II, perforin and granzymes. These changes were present two days post chemokine modulation and subsided within one week.

CONCLUSION

The chemokine-modulating IP-CITC is safe, tolerable, and associated with ISG changes that favor CTL chemoattraction and function. This combination (plus DC vaccine) will be tested in a phase II trial.

Estimating the financial costs associated with a phase III, multi-site exercise intervention trial: Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE)

INTRODUCTION

Supervised exercise interventions are expensive and time intensive. However, there are financial costs to consider in addition to the intervention itself, namely: advertising and recruitment, outcome assessments, and other trial-related costs.

OBJECTIVES

In this analysis, we examine the financial costs associated with the administration of Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE) to quantify the costs associated with large exercise intervention trials and to provide future investigators with financial estimates if they wish to pursue studies of a similar design.

METHODS

Cost per randomized participant were calculated in four areas: (1) advertising and recruitment, (2) outcome assessments, (3) delivery of the intervention, and (4) other trial-related expenses. Overall trial costs associated with data analysis, faculty salaries, and indirect costs were estimated as well.

RESULTS

The total cost per randomized participant was estimated to be $16,494. Outcome assessments accounted for the highest proportion of per-participant (75%) and total trial (38%) costs. Neuroimaging assessments (MRI & PET) cost $8247 per randomized participant, accounting for two-thirds (67%) of outcome assessment costs and half (50%) of per-participant costs.

CONCLUSION

Large clinical trials of exercise are expensive (~$21 million), particularly when administering several visits to assess study aims. Outcome assessments, specifically those involving neuroimaging, accounted for a significant proportion of total costs in this analysis. Future investigators must budget accordingly if they wish to conduct a comprehensive, multi-site exercise intervention trial that examines numerous physiological and psychological outcomes.

Promoting collaborative psychiatric care decision-making in community mental health centers: Insights from a patient-centered comparative effectiveness trial

OBJECTIVE

Mental health service-users face important medication decisions; yet not all are active participants in the decision-making process. Little is known about which technology-supported interventions might effectively promote collaborative decision-making in psychiatric care. We compared the effectiveness of two technology-supported collaborative care decision-making approaches.

METHOD

We used a cluster-randomized design with a mixed-methods approach. Participants were Medicaid-enrolled adults receiving psychiatric care in participating community mental health centers. Measurement-based care used computerized systematic symptom and medication screenings to inform provider decision-making. Person-centered care supported participants in completing computerized Health Reports and preparing to work with providers on collaborative decision-making about psychiatric care. Primary study outcomes included the patient experience of medication management and shared decision-making during psychiatric care. Analyses examined the impact of both approaches and explored moderating variables. We used qualitative methods to understand participation and implementation experiences.

RESULTS

Across 14 sites 2,363 participants enrolled (1,162 in measurement-based care, 1,201 in person-centered care). We observed statistically significant improvements in patient experience of medication management scores for both study arms; however, the clinical significance of this change was minor. We found no significant changes for shared decision-making. Qualitative interviews revealed a range of factors associated usefulness of intervention assessment, provider-service-user communication, and site-level logistics.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

We observed modest positive findings related to our patient-centered outcomes. We identified important implementation facilitators and barriers that can inform the implementation of future comparative effectiveness patient-centered research. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Stakeholder impact on the implementation of integrated care: Opportunities to consider for patient-centered outcomes research

Nearly half of Americans live with chronic disease. Many have multiple chronic conditions that often present as a combination of physical and mental health conditions. Aligning stakeholder-driven, patient-centered outcomes research with population health strategies such as innovative ways to deliver care management can reduce the burden of multiple chronic conditions. In addition, successfully creating meaningful, inclusive research requires actively engaging stakeholders throughout the lifecycle of a study. This study integrates stakeholder engagement, using a large health plan in western Pennsylvania, to conduct a randomized controlled trial. Three care management strategies, High-Touch, High-Tech, and Usual Care, are compared for effectiveness among members with multiple chronic conditions. Care strategies are delivered via the Community Team, a multidisciplinary community-based team, offering in-person (High-Touch) and digital (High-Tech) care management in 14 counties across Pennsylvania. Participants are followed for 12months, with repeated measurements of self-reported health status and activation in care, while tracking administrative measurements of primary and specialty health service utilization. Quality of life, care satisfaction, engagement in care, and service utilization will be compared using generalized mixed models. Additionally, semi-structured interviews are conducted for both participants and care managers over the course of the study to evaluate feasibility. This manuscript presents implementation strategies, while noting that the implementation of patient-centered outcomes research in a real-world setting requires rapid evaluation, redesign of workflow, and tailored approaches for success.

Exercise interventions preserve hippocampal volume: A meta-analysis

Hippocampal volume is a marker of brain health and is reduced with aging and neurological disease. Exercise may be effective at increasing and preserving hippocampal volume, potentially serving as a treatment for conditions associated with hippocampal atrophy (e.g., dementia). This meta-analysis aimed to identify whether exercise training has a positive effect on hippocampal volume and how population characteristics and exercise parameters moderate this effect. Studies met the following criteria: (a) controlled trials; (b) interventions of physical exercise; (c) included at least one time-point of hippocampal volume data before the intervention and one after; (d) assessed hippocampal volume using either manual or automated segmentation algorithms. Animal studies, voxel-based morphometry analyses, and multi-modal interventions (e.g., cognitive training or meditation) were excluded. The primary analysis in n = 23 interventions from 22 published studies revealed a significant positive effect of exercise on total hippocampal volume. The overall effect was significant in older samples (65 years of age or older) and in interventions that lasted over 24 weeks and had less than 150 min per week of exercise. These findings suggest that moderate amounts of exercise for interventions greater than 6 months have a positive effect on hippocampal volume including in older populations vulnerable to hippocampal atrophy.

The IGNITE trial: Participant recruitment lessons prior to SARS-CoV-2

Full and diverse participant enrollment is critical to the success and generalizability of all large-scale Phase III trials. Recruitment of sufficient participants is among the most significant challenges for many studies. The novel SARS-CoV-2 coronavirus pandemic has further changed and challenged the landscape for clinical trial execution, including screening and randomization. The Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE) study has been designed as the most comprehensive test of aerobic exercise effects on cognition and brain health. Here we assess recruitment into IGNITE prior to the increased infection rates in the United States, and examine new challenges and opportunities for recruitment with a goal of informing the remaining required recruitment as infection containment procedures are lifted. The results may assist the design and implementation of recruitment for future exercise studies, and outline opportunities for study design that are flexible in the face of emerging threats.

Changes in cerebral perfusion following a 12-month exercise and diet intervention

Overweight and obesity may damage the cerebrovascular architecture, resulting in a significant reduction in cerebral blood flow. To date, there have been few randomized clinical trials (RCT) examining whether obesity-related reductions in cerebral blood flow could be modified by weight loss. Further, it is unknown whether the behavioral intervention strategy for weight loss (i.e., diet alone or diet combined with exercise) differentially influences cerebral blood flow in adults with overweight or obesity. The primary aim of this study was to determine whether a 12-month RCT of exercise and diet increases cerebral blood flow in 125 midlife (Mean age ± SD = 44.63 ± 8.36 years) adults with overweight and obesity. Further, we evaluated whether weight loss via diet combined with aerobic exercise has an added effect on changes in cerebral blood flow compared to weight loss via diet alone and whether there were regionally specific effects of the type of behavioral intervention on cerebral blood flow patterns. Consistent with our predictions, a 12-month diet and exercise program resulting in 10% weight loss increased cerebral blood flow. These effects were widespread and extended throughout frontal, parietal, and subcortical regions. Further, there was some regional specificity of effects for both diet-only and diet combined with exercise. Our results demonstrate that weight-related reductions in cerebral blood flow can be modified by 10% weight loss over the course of 12 months and that interventions involving exercise exposure may provide unique effects on cerebral blood flow compared to interventions involving only diet.

Feasibility of implementing mobile technology-delivered mental health treatment in routine adult sickle cell disease care

Sickle cell disease (SCD) is a severe hemoglobinopathy characterized by acute and chronic pain. Sufferers of the disease, most of whom are underrepresented minorities, are at increased risk for mental health disorders. The purpose of this study is to test the acceptability and implementation of a computerized cognitive behavioral therapy (cCBT) intervention, Beating the Blues, to improve depression, anxiety, and pain in patients with SCD. Adults with SCD and significant symptoms of depression (Patient Health Questionnaire [PHQ-9] score ≥ 10) or anxiety (Generalized Anxiety Disorder Scale [GAD-7] score ≥ 10) were eligible to participate and be randomized to either receive eight sessions of cCBT with care coach support or treatment as usual. Participants reported daily pain and mood symptoms using a mobile diary app. Depression, anxiety, and pain symptoms were assessed at 1, 3, and 6 months. Thirty patients were enrolled: 18 to cCBT, and 12 to control. The cCBT intervention was feasible to implement in clinical settings and acceptable to participants. Patients in the cCBT arm reported a marginally greater decrease in depression at 6 months (-3.82, SE = 1.30) than those in the control group (-0.50, SE = 1.60; p = .06). There were no significant effects of treatment on anxiety; however, cCBT was associated with improved daily pain reported via a mobile diary app (p = .014). cCBT, delivered via mobile device, is a feasible strategy to provide mental health care to adults living with SCD. cCBT was acceptable to the target population; was able to be implemented in real-world, nonideal conditions; and has the potential to improve patient-reported outcomes.

Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE): Protocol

Despite the ubiquity of normal age-related cognitive decline there is an absence of effective approaches for improving neurocognitive health. Fortunately, moderate intensity exercise is a promising method for improving brain and cognitive health in late life, but its effectiveness remains a matter of skepticism and debate because of the absence of large, comprehensive, Phase III clinical trials. Here we describe the protocol for such a randomized clinical trial called IGNITE (Investigating Gains in Neurocognition in an Intervention Trial of Exercise), a study capable of more definitively addressing whether exercise influences cognitive and brain health in cognitively normal older adults. We are conducting a 12-month, multi-site, randomized dose-response exercise trial in 639 cognitively normal adults between 65 and 80 years of age. Participants are randomized to (1) a moderate intensity aerobic exercise condition of 150 min/week (N = 213), (2) a moderate intensity aerobic exercise condition at 225 min/week (N = 213), or (3) a light intensity stretching-and-toning control condition for 150 min/week (N = 213). Participants are engaging in 3 days/week of supervised exercise and two more days per week of unsupervised exercise for 12 months. A comprehensive cognitive battery, blood biomarkers and battery of psychosocial questionnaires is assessed at baseline, 6 and 12-months. In addition, brain magnetic resonance imaging, physiological biomarkers, cardiorespiratory fitness, physical function, and positron emission tomography of amyloid deposition are assessed at baseline and at the 12-month follow-up. The results from this trial could transform scientific-based policy and health care recommendations for approaches to improve cognitive function in cognitively normal older adults.

Cesarean delivery to prevent anal incontinence: a systematic review and meta-analysis

BACKGROUND

Cesarean delivery (CD), is increasingly recommended as a mode of delivery that prevents the anal incontinence (AI) that arises in some women after vaginal delivery (VD). The assessment of the efficacy of CD in this regard was the subject of this systematic review.

METHODS

Searches were conducted in Medline, EMBASE and the Cochrane Library. Both randomized (RCTs) and non-randomized trials (NRTs) comparing the risk of sustained fecal and/or flatus incontinence after VD or CD were sought from 1966 to 1 January, 2019. Studies were eligible if they assessed AI more than 6 months after birth, and had statistical adjustment for at least one of the three major confounders for AI: age, maternal weight or parity. In addition, each study was required to contain more than 250 participants, more than 50 CDs and more than 25 cases of AI. Data after screening and selection were abstracted and entered into Revman for meta-analysis. Analyses were done for combined fecal and flatus incontinence (comAI), fecal incontinence (FI), gas incontinence (GI), CD before or during labor, time trend of incontinence after delivery, assessment of both statistical and clinical heterogeneity, parity and late incident AI.

RESULTS

Out of the 2526 titles and abstracts found, 24 eligible studies were analyzed, 23 NRTs and one RCT. These included women with 29,597 VDs and women with 6821 CDs. Among the primary outcomes, VD was found not to be a significant predictor of postpartum comAI compared to CD in 6 studies, incorporating 18,951 deliveries (OR = 0.74; 0.54-1.02). VD was also not a significant predictor of FI in 14 studies, incorporating 29,367 deliveries, (OR = 0.89; 0.76-1.05). VD was not a significant predictor of GI in six studies, incorporating 6724 deliveries (OR = 0.96; 0.79-1.18). The strength of the grading of recommendations, assessment, development and evaluations (GRADE) evidence for each of these was low for comAI and moderate for FI and GI (upgrade for lack of expected effect). Time trend FI showed incontinence at 3 months often resolved at 1 year. Other secondary analyses assessing parity, delayed incidence of FI, clinical and statistical heterogeneity, spontaneous VD only, late risk of incidence of AI, and CD in or prior to labor all had similar results as in the primary outcomes.

CONCLUSIONS

There are three components of pelvic floor dysfunction that are thought to be caused by VD and hopefully prevented by CD: AI, urinary incontinence and pelvic floor prolapse. Of these, AI was not found to be reliably prevented by CD in this review.

Weight-Loss Outcomes from a Pilot Study of African Dance in Older African Americans

OBJECTIVE

Obesity is a risk factor for both cognitive and physical impairment in late adulthood. Though the rates of obesity are high in many groups, older African Americans are disproportionately affected. A randomized pilot intervention of African Dance was conducted with 28 African American older adults with obesity (mean age = 68.4 ± 5.1 years; mean BMI = 33.4 ± 6.2). The goal of the study was to evaluate the physiological outcomes of a culturally sensitive exercise intervention and specifically changes in weight.

METHODS

Participants were randomly assigned to an African Dance (experimental) or Culture Education (control) group. They attended their assigned class for 1 hour per session, 3 days per week, for 6 months.

RESULTS

There was a significant group × time interaction on weight (P  = 0.005) such that the African Dance group lost weight (mean = 4.0 ± 6.0 lb) while the Culture Education group gained weight (mean = 2.6 ± 3.9 lb).

CONCLUSIONS

These results suggest that a culturally sensitive form of physical activity, African Dance, may be effective for promoting weight loss in a population at increased risk for obesity and cognitive decline.

Racial and Socioeconomic Disparities in Hysterectomy Route for Benign Conditions

BACKGROUND

The aim of this paper was to explore disparities associated with the route of hysterectomy in the University of Pittsburgh Medical Center (UPMC) health system and to evaluate whether the hysterectomy clinical pathway implementation impacted disparities in the utilization of minimally invasive hysterectomy (MIH).

METHODS

We performed a retrospective medical record review of all the patients who have undergone hysterectomy for benign indications at UPMC-affiliated hospitals between fiscal years (FY) 2012 and 2014.

RESULTS

A total number of 6373 hysterectomy patient cases were included in this study: 88.7% (5653) were European American (EA), 11.02% (702) were African American (AA), and the remaining 0.28% (18) were of other ethnicities. We found that non-EA, women aged 45-60, traditional Medicaid, and traditional Medicare enrollees were more likely to have a total abdominal hysterectomy (TAH). Residence in higher median income zip code (> $61,000) was associated with 60% lower odds of undergoing TAH. Both FY 2013 and 2014 were associated with significantly lower odds of TAH. Logistic regression results from the model for non-EA patients for FY 2012 and FY 2014 demonstrated that FY and zip code income group were not significant predictors of surgery type in this subgroup. Pathway implementation did not reduce racial disparity in MIH utilization.

CONCLUSION

This study demonstrated that there is a significant disparity in MIH utilization, where non-EA and Medicaid/Medicare recipients had higher odds of undergoing TAH. Further research is needed to investigate how care standardization may alleviate healthcare disparities.

Anion gap and base deficit are predictors of mortality in acute pesticide poisoning

BACKGROUND:

Acute pesticide poisoning has long been a serious problem as a method of suicide worldwide. This poisoning is a highly fatal condition that requires a rapid and precise diagnosis for adequate treatment. However, various studies on mortality predictor factors have been insufficient for whole pesticide treatments. We hypothesized that the initial plasma anion gap (AG) and base deficit (BD) are reliable prognostic factors.

METHODS:

A retrospective study analyzed 561 patients with a diagnosis of acute pesticide poisoning between January 1, 2014 and June 30, 2017. The initial AG and BD values were divided into quartiles according to the number of patients. Survival at 30 days from admission was estimated using the Kaplan-Meier survival analysis. Receiver-operator characteristic (ROC) curves were drawn, and the areas under the curve for AG and BD for mortality were calculated.

RESULTS:

Fifty-eight (10.3%) of 561 patients died within 30 days. The highest AG quartile (>22 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with an AG less than 14.7 mEq/L, these patients had a 4.18-fold higher risk of 30-day hospital mortality and the highest BD quartile (>7.9 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with a BD less than 1.4 mEq/L, these patients had 2.23-fold higher risk of 30-day hospital mortality. The areas under the ROC for AG and BD curve were 0.699 and 0.744, respectively.

CONCLUSIONS:

Initial high AG and BD values could predict mortality and require precise intensive care.

Evaluation of biomarkers for treatment selection using individual participant data from multiple clinical trials

Biomarkers that predict treatment effects may be used to guide treatment decisions, thus improving patient outcomes. A meta-analysis of individual participant data (IPD) is potentially more powerful than a single-study data analysis in evaluating markers for treatment selection. Our study was motivated by the IPD that were collected from 2 randomized controlled trials of hypertension and preeclampsia among pregnant women to evaluate the effect of labor induction over expectant management of the pregnancy in preventing progression to severe maternal disease. The existing literature on statistical methods for biomarker evaluation in IPD meta-analysis have evaluated a marker's performance in terms of its ability to predict risk of disease outcome, which do not directly apply to the treatment selection problem. In this study, we propose a statistical framework for evaluating a marker for treatment selection given IPD from a small number of individual clinical trials. We derive marker-based treatment rules by minimizing the average expected outcome across studies. The application of the proposed methods to the IPD from 2 studies in women with hypertension in pregnancy is presented.

Predictors of Revisit and Admission after Discharge from an Emergency Department in Acute Pyelonephritis

Introduction

The aim of this study is to construct clinical prediction models to predict emergency department (ED) return visit following initial discharge for acute pyelonephritis (APN) and the need for hospital re-admission upon ED return visits.

Method

A retrospective analysis included 1250 discharged women with APN. Independent risk factors for revisit and subsequent admission after revisit were determined by multivariate analysis, and a prediction model for revisit and subsequent admission after revisit was constructed.

Results

Independent risk factors for revisit were nausea (2 points), age ≥ 65 years (2 points), C-reactive protein >20 mg/dL (2 points), serum albumin <3.3 g/dL (3 points) and urine white blood cell count ≥ 30/high power field (2 points). Re-visit risk scores were categorised to five groups and the re-visit rate was 5.4%, 8.6%, 12.2%, 19.1% and 43.8%, respectively, showing an area under curve (AUC) of 0.62. Risk factors for subsequent admission after revisit were vomiting (1 point), hypertension (2 points), serum creatinine <1.5 mg/dL (2 points), C-reactive protein >20 mg/dL (2 points) and serum albumin <3.3 g/dL (4 points). The subsequent admission after revisit risk scores were classified to three groups and subsequent admission after revisit rate was 3.5%, 15.0%, and 38.2%, respectively.

Conclusion

The developed model can identify a group of patients at high risk for a return visit and for requiring subsequent hospital admission, and might be used to improve initial disposition decision and discharge instructions. (Hong Kong j.emerg. med. 2015;22:154-162)

Hybrid Statistical and Mechanistic Mathematical Model Guides Mobile Health Intervention for Chronic Pain

Nearly a quarter of visits to the emergency department are for conditions that could have been managed via outpatient treatment; improvements that allow patients to quickly recognize and receive appropriate treatment are crucial. The growing popularity of mobile technology creates new opportunities for real-time adaptive medical intervention, and the simultaneous growth of "big data" sources allows for preparation of personalized recommendations. Here we focus on the reduction of chronic suffering in the sickle cell disease (SCD) community. SCD is a chronic blood disorder in which pain is the most frequent complication. There currently is no standard algorithm or analytical method for real-time adaptive treatment recommendations for pain. Furthermore, current state-of-the-art methods have difficulty in handling continuous-time decision optimization using big data. Facing these challenges, in this study, we aim to develop new mathematical tools for incorporating mobile technology into personalized treatment plans for pain. We present a new hybrid model for the dynamics of subjective pain that consists of a dynamical systems approach using differential equations to predict future pain levels, as well as a statistical approach tying system parameters to patient data (both personal characteristics and medication response history). Pilot testing of our approach suggests that it has significant potential to well predict pain dynamics, given patients reported pain levels and medication usages. With more abundant data, our hybrid approach should allow physicians to make personalized, data-driven recommendations for treating chronic pain.

Implementation of Hysterectomy Pathway: Impact on Complications

OBJECTIVE

Hysterectomy is one of the most common surgical procedures in the United States. For women who need hysterectomy, it is important to ensure that minimally invasive hysterectomy procedures are used appropriately to reduce surgical complications and improve value of care. Although we previously demonstrated a reduction in total abdominal hysterectomy rates after the implementation of hysterectomy pathway treatment algorithm in 2012, this study focuses on exploring the effect of pathways implementation on surgical outcomes.

METHODS

All retrospective medical records for hysterectomy surgeries performed for benign indications at University of Pittsburgh Medical Center hospitals between the fiscal years (FY) 2012 and 2014 were identified. We analyzed the health care outcomes by route of surgery and year using Χ² test for categorical data, and non-parametric approaches for non-normal continuous variables.

RESULTS

A total of 6,569 hysterectomies for benign indications were performed between FY 2012 and 2014. In FY 2012, 1,154 patients (59.15%) had a length of stay of 1 day or less, whereas in FY 2014 this number increased to 1,791 (74.53%; p < .0001). Within 3 years of implementing the pathway, surgical site infections had a reduction of 47%, with a considerable trend toward significance (p = .067).

CONCLUSIONS

Implementation of hysterectomy pathway has been associated with reduction of surgical complications in benign hysterectomy settings. Implementation of clinical pathways offers an opportunity for improving patient outcomes that should be investigated in various health care settings and across procedures.

Sodiation-based in-source collision for profiling of pyranocoumarins in Radix Peucedani (Qianhu): utility of sodium adducts' stability with in-source collision

Full scan mode of liquid chromatography-mass spectrometry equipped with an electrospray ionization source offers a chance on global detection of complicated components; however, the scan mode carries significant challenges in rapidly capturing information of analysts. Sodiation-based in-source collision was proposed here, as a technique for rapid detecting untargeted analytes in full scan analysis, which was based on the stability of sodium adducts and the nonselectivity of in-source collision. Then the technique was applied to profile of angular-type pyranocoumarins (APs) in Radix Peucedani, with full scan analysis performed at two specific in-source collision energy: a high energy 50 V that is tolerated by the sodium adducts of APs, and a low energy 10 V, at which abundant adducts were offered. The spectra list of two average mass spectra was exported, and stable ions were selected based on the intensity ratio of standards at the two collision energy. Then 27 plausible [M + Na]⁺ m/z values of APs were acquired after filtering the fragment ion and isotope ions and validating with [M + NH₄ ]⁺ . Eighty-two APs finally were tentatively identified based on their accurate spectral data of MSⁿ , fragmentation rules, and elution order regardless of their absolute configuration, which included 25 reported APs from Peucedanum praeruptorum Dunn. The technique provided a novel application of sodium adduct in qualitative analysis. And it was valuable for rapidly capturing information of analytes in full scan analysis, not only for APs but also for other compounds that could form sodium adducts. Copyright © 2017 John Wiley & Sons, Ltd.

Base deficit is a predictor of mortality in organophosphate insecticide poisoning

OBJECTIVE

Organophosphate insecticide (OPI) self-poisoning is a major medical problem in many countries. Several studies have demonstrated that the base deficit (BD) is a prognostic tool that is correlated with the severity of injury and predicted mortality, particularly in trauma patients. Here, we aimed to investigate the prognostic significance of BD in OPI poisoning.

METHODS

This retrospective observational study was conducted between January 1, 2006, and January 31, 2015, at a single emergency department (ED). The BD values were divided into quartiles according to the number of patients: 3 mEq/L or less, 3-5.9 mEq/L, 6-9.9 mEq/L, and 10 mEq/L or greater. Survival at 30 days from ED admission was estimated using the Kaplan-Meier survival analysis.

RESULTS

Among 154 patients, 31 died, yielding a mortality of 20.1%. The highest BD quartile (≥ 10 mEq/L) and the 6-9.9 mEq/L group were associated with an increased risk of 30-day mortality. Patients with a BD of 10 mEq/L or greater had a 5.85-fold higher risk of 30-day mortality and patients with a BD of 6-9.9 mEq/L had a 5.40-fold higher risk of 30-day mortality compared to patients with a BD of 3 mEq/L or less. The area under the curves of the BD and the Acute Physiology and Chronic Health Evaluation II score for mortality were 0.748 (95% confidence interval (CI), 0.660-0.835) and 0.852 (95% CI, 0.789-0.915), respectively.

CONCLUSIONS

This study showed that the BD is a predictor of 30-day mortality in patients with OPI poisoning.

Muscle immobilization activates mitophagy and disrupts mitochondrial dynamics in mice

AIM

Skeletal muscle atrophy following prolonged immobilization (IM) is a catabolic state characterized by increased proteolysis and functional deterioration. Previous research indicates that discord of mitochondrial homoeostasis plays a critical role in muscle atrophy. We hypothesized that muscle IM would activate the ubiquitin-proteolysis, autophagy-lysosome (mitophagy) pathway, mitochondrial dynamics remodelling and apoptosis partially controlled by the FoxO signalling pathway.

METHODS

Female FVB/N mice were randomly divided into five groups (n = 8 each): control (CON), IM with banding of one of the hindlimbs for 1, 2 and 3 weeks (1w-, 2w- and 3w-IM) and 2w-IM followed by 1 week of remobilization (RM).

RESULTS

Mitochondrial density and DNA copies in tibialis anterior (TA) muscle were reduced by approx. 80% (P < 0.05 for 2w-IM; P < 0.01 for 3w-IM), along with activation of FoxO3a, atrogin-1 and MuRF1 following 2w- and 3w-IM (P < 0.01). Protein markers of autophagy/mitophagy, such as beclin 1 (approx. 2.7-fold; P < 0.01), LC3, ubiquitin-binding adaptor (approx. 1.47-fold; P < 0.01), Rheb (approx. 1.9-fold; P < 0.05) and parkin (approx. 70%; P < 0.05), were all increased by IM and remained activated after RM, whereas BNIP3 and PINK1 levels were decreased by IM (P < 0.05), but elevated upon RM (P < 0.01). IM decreased Mfn2 expression (approx. 50%; P < 0.01) and increased Fis-1 expression (approx. 2.4-fold; P < 0.05). Muscle apoptosis indicator Bax/Bcl2 ratio was elevated at 2w- to 3w-IM (approx. 3.7-fold; P < 0.01), whereas caspase-3 activity was five- to sixfold higher (P < 0.01) and remained threefold higher above CON (P < 0.05).

CONCLUSION

Our data indicate that IM-induced mitochondrial deterioration is associated with altered protein expressions in the autophagic/mitophagic pathway, more fragmented mitochondrial network and activation of apoptosis partly under the influence of FoxO3 activation.

Challenges encountered in the conduct of Optimal Health: A patient-centered comparative effectiveness study of interventions for adults with serious mental illness

BACKGROUND

The aim of patient-centered comparative effectiveness research is to conduct stakeholder-driven investigations that identify which interventions are most effective for which patients under specific circumstances. Conducting this research in real-world settings comes with unique experiences and challenges. We provide the study design, challenges confronted, and the solutions we devised for Optimal Health, a stakeholder-informed patient-centered comparative effectiveness study focused on the needs of seriously mentally ill individuals receiving case management services in community mental health centers across Pennsylvania.

METHODS

Optimal Health, supported by the Patient-Centered Outcomes Research Institute, is a cluster-randomized trial of two evidence-based interventions for improving health and wellness across 11 provider sites. Participants were followed for 18-24 months, with repeated measurements of self-reported health status and activation in care and administrative measurements of primary and specialty health service utilization. Health-related quality of life, engagement in care, and service utilization are to be compared via random effects mixed models. Stakeholders were, and continue to be, engaged via focus groups, interviews, and stakeholder advisory board meetings. A learning collaborative model was used to support shared learning and implementation fidelity across provider sites.

RESULTS

From 1 November 2013 through 15 July 2014, we recruited 1229 adults with serious mental illness, representing 85.1% of those eligible for study participation. Of these, 713 are in the Provider-Supported arm of the study and 516 in Patient Self-Directed Care. Across five data collection time points, we retained 86% and 83% of the participants in the Provider-Supported and Self-Directed arms, respectively.

LESSONS LEARNED

Lessons learned relate to estimation of the size of our study population, the value of multiple data sources, and intervention training and implementation. The use of historical claims data can lead to an overestimation of eligible participants and, subsequently, a reduced study sample and an imbalance between intervention arms. Disruptions in continuity of care in real-world settings can pose challenges to on-site self-report data collection, although the inclusion of multiple data sources in study design can improve data completeness. Geographic dispersion of rural provider sites and staff turnover can lead to training and intervention fidelity challenges that can be overcome with the use of a "train-the-trainer" model, "wellness champions," and the use of a Learning Collaborative approach. Stakeholder engagement in mitigating these challenges proved to be critical to study progress.

CONCLUSION

Conducting real-world patient-centered comparative effectiveness research in healthcare systems that care for seriously mentally ill persons is an important yet challenging undertaking, one which requires flexibility in identifying potential adaptations within all major study phases. Advice from a wide range of stakeholders is critical in development of successful strategies.

Presentation of available CTL epitopes that induction of cell-mediated immune response against HIV-1 Koran clade B strain using computational technology

OBJECTIVE

Theoretical predicting cytotoxic T lymphocyte (CTL) epitopes are an important tool in vaccine design and CTL therapy for enhancing our understanding of the cellular immune system. We would like to identify available CTL epitopes against HIV-1 Korean clade B. CTL activity was assessed in freshly isolated peripheral blood mononuclear cells from Korean HIV patients in order to assess whether these CTL epitopes induce a cell-mediated immune response (CMI).

METHODS

NetCTLpan1.1 software, which is the most popular prediction computer software package, and full atom-based simulation (FABS), which is a 3D modelling system for binding activity between epitopes and human leucocyte antigen (HLA) molecules, were used to predict the peptide-spanning Env region binding to HLA-A*24:02, HLA-A*02:01 and HLA-B*15:01, which are frequently found in the Korean population. Granzyme B and interferon-γ ELISPOT assays were used to determine whether identified CTL epitopes induce CMI.

RESULTS

Three HIV-1 Korean clade B-specific Env CTL epitopes were identified: Gp41-RYL and Gp41-RQG are localized within gp41, and Gp120-LLQ within gp120. In in vitro assays using granzyme B ELISPOT, Gp120-LLQ and Gp41-RQG induced epitope-specific CTL responses in HLA-restricted cells. In ex vivo assay using IFN-γ ELISPOT, cell-mediated immune responses to Gp41-RYL were present in 50% of HLA-matched patients, and responses to Gp120-LLQ and Gp41-RQG were found in 33% of HLA-matched patients.

CONCLUSION

In this study, we found that a prediction pipeline for CTL epitopes might be based on the most popular computer prediction software and FABS methods. Our results suggest that these CTL epitopes may provide useful tools and information for the development of a therapeutic vaccine against HIV-1 Korean clade B.

External validation of the prognostic index in acute paraquat poisoning

OBJECTIVE

Some studies have evaluated the prognostic indicators associated with acute paraquat (PQ) poisoning. In this study, we externally validated the Yamaguchi index, which showed a good prognostic relevance in predicting the outcome of PQ poisoning.

METHODS

A retrospective analysis of 297 patients was performed. The Yamaguchi index was calculated using the following equation: Eq1 = (K(+) × HCO3(-))/(Creatinine × 0.088)(mEq/L) against time from PQ ingestion (T). The patients were divided into three groups: group A: Eq1 > 1500 - 399 × log T, group B: 930 - 399 × log T < Eq1 ≤ 1500 - 399 × log T, and group C: Eq1 ≤ 930 - 399 × log T).

RESULTS

The overall mortality rate was 65.3% (194 of 297). The mortality rates of the three groups stratified by the Yamaguchi index were 7.1% (2 of 28), 22.4% (15 of 67), and 87.6% (177 of 202). The area under the receiver-operating characteristic curve for predicting mortality from the external validation of the Yamaguchi index was 0.842 (95% confidence interval: 0.795-0.882).

CONCLUSION

The Yamaguchi index is a reliable prognostic factor and could be helpful in predicting mortality due to PQ poisoning.

Synthesis and properties of fluorescence poly(benzoxazole–imide)s containing naphthalene

Novel aromatic poly(benzoxazole–imide)s containing naphthalene were prepared from synthesized 1,4-di(5-aminobenzoxazol-2-yl)naphthalene and commercial dianhydrides by conventional two-step polymerization. The polymers showed high levels of tensile strength of up to 294 MPa and modulus of up to 6.5 GPa. The glass transition temperatures of the polymers were observed between 267°C and 345°C. The 5% weight loss temperatures of the polymers were tested in the range of 517–562°C in nitrogen atmosphere. The excellent properties of polymers were attributed to their rigid-rod-like molecular structure. The polymers emitted different fluorescence with maximum emission wavelengths in the range of 470–560 nm. Increasing the dianhydride electron affinity, the emission spectra peak value of polyimides (PIs) except PI6 increased gradually, but the fluorescent intensity of the PIs decreased. The 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride-derived PI film exhibit highly fluorescent characteristics; however, the PI film from pyromellitic dianhydride was nonfluorescent.

Blockade of the T cell immunoglobulin and mucin domain protein 3 pathway exacerbates sepsis-induced immune deviation and immunosuppression

Sepsis is a life-threatening condition, but the pathophysiological basis and biomarkers for the monitoring of sepsis and as targets for therapy remain to be determined. We have shown previously that T cell immunoglobulin and mucin domain protein 3 (Tim-3), a negative immune regulator, is involved in the physiopathology of sepsis, but the underlying mechanisms remain unclear. In the present study, we showed that Tim-3 signalling modulated the response patterns of both macrophages and T helper cells in sepsis. Blockade of the Tim-3 pathway exacerbated sepsis-induced proinflammatory macrophage responses and lymphocyte apoptosis during the early phase of sepsis, and enhanced the shift to anti-inflammatory responses for both macrophages and T helper cells during the late phase of sepsis. Tim-3 signalling was found to regulate CD80 and CD86 expression on macrophages both in vivo and in vitro. Co-culture of T cells with Tim-3 knock-down macrophages led to a biased T helper type 2 (Th2) response, partially explaining how Tim-3 signalling shapes inflammation patterns in vivo. Further studies on this pathway might shed new light on the pathogenesis of sepsis and suggest new approaches for intervention.

Correlation research of carotid arterial sclerosis and left ventricular diastolic function in hyperthyroidism

AIM

This study aims to investigate the correlation of carotid arterial sclerosis and left ventricular diastolic function in hyperthyroidism.

METHODS

A total of 70 patients with newly-diagnosed hyperthyroidism, including 32 patients clinically cured or improved after I131 therapy, were compared with 74 healthy cases in the control group. Bilateral carotid ultrasound and echocardiography were performed in all subjects. The carotid sclerosis index B, compliance coefficient CC, pulse wave velocity (PWV) and left ventricular diastolic function parameters (mitral valve diastolic peak velocity ratio E/A, mitral annulus tissue Doppler diastolic peak velocity ratio e/a and E/e) were obtained.

RESULTS

The B, CC, PWV and E/e exhibited correlation. Pre-treatment CC was negatively correlated with E/e (r=-0.325, P<0.01), whereas B and PWV were positively correlated with E/e (r=0.270 and 0.297, P < 0.05). Post-treatment CC was negatively correlated with E/e (r=-0.462, P<0.01), whereas B and PWV were positively correlated with E/e (r=0.513 and 0.479, P<0.01).

CONCLUSION

Carotid artery function and left ventricular diastolic function of hyperthyroid patients were damaged before the treatment and recovered after the treatment. Thus, a correlation existed between them. The early detection of carotid artery function could help the early detection of cardiovascular disease in the hyperthyroid patients.

A discrete-time survival model with random effects for designing and analyzing repeated low-dose challenge experiments

Repeated low-dose (RLD) challenge designs are important in HIV vaccine research. Current methods for RLD designs rely heavily on an assumption of homogeneous risk of infection among animals, which, upon violation, can lead to invalid inferences and underpowered study designs. We propose to fit a discrete-time survival model with random effects that allows for heterogeneity in the risk of infection among animals and allows for predetermined challenge dose changes over time. Based on this model, we derive likelihood ratio tests and estimators for vaccine efficacy. A two-stage approach is proposed for optimizing the RLD design under cost constraints. Simulation studies demonstrate good finite sample properties of the proposed method and its superior performance compared to existing methods. We illustrate the application of the heterogeneous infection risk model on data from a real simian immunodeficiency virus vaccine study using Rhesus Macaques. The results of our study provide useful guidance for future RLD experimental design.