Predictors of SARS-CoV-2 transmission in congregate living settings: a multicenter prospective study

BACKGROUND

Older adults residing in congregate living settings (CLS) such as nursing homes and independent living facilities remain at increased risk of morbidity and mortality from coronavirus disease 2019. We performed a prospective multicenter study of consecutive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) exposures to identify predictors of transmission in this setting.

METHODS

Consecutive resident SARS-CoV-2 exposures across 17 CLS were prospectively characterized from 1 September 2022 to 1 March 2023, including factors related to environment, source, and exposed resident. Room size, humidity, and ventilation were measured in locations where exposures occurred. Predictors were incorporated in a generalized estimating equation model adjusting for the correlation within CLS.

RESULTS

Among 670 consecutive exposures to SARS-CoV-2 across 17 CLS, transmission occurred among 328 (49.0%). Increased risk was associated with nursing homes (odds ratio (OR) = 90.8; 95% CI, 7.8-1047.4), Jack and Jill rooms (OR = 2.2; 95% CI, 1.3-3.6), from source who was pre-symptomatic (OR = 11.2; 95% CI, 4.1-30.9), symptomatic (OR = 6.5; 95% CI, 1.4-29.9), or rapid antigen test positive (OR = 35.6; 95% CI, 5.6-225.6), and in the presence of secondary exposure (OR = 6.3; 95% CI, 1.6-24.0). Exposure in dining room was associated with reduced risk (OR = 0.02; 95% CI, 0.005-0.08) as was medium room size (OR = 0.3; 95% CI, 0.2-0.6). Recent vaccination of exposed resident (OR = 0.5; 95% CI, 0.3-1.0) and increased ventilation of room (OR = 0.9; 95% CI, 0.8-1.0) were marginally associated with reduced risk.

CONCLUSION

Prospective assessment of SARS-CoV-2 exposures in CLS suggests that source characteristics and location of exposure are most predictive of resident transmission. These findings can inform risk assessment and further opportunities to prevent transmission in CLS.

Treatment affects load to failure and microdamage accumulation in healthy and osteolytic rat vertebrae

Bone turnover and microdamage are impacted by the presence of skeletal metastases which can contribute to increased fracture risk. Treatments for metastatic disease may further impact bone quality. This exploratory study aimed to establish an initial understanding of microdamage accumulation and load to failure in healthy and osteolytic rat vertebrae following focal and systemic cancer treatment (docetaxel (DTX), stereotactic body radiotherapy (SBRT), or zoledronic acid (ZA)). Osteolytic spine metastases were developed in 6-week-old athymic female rats via intracardiac injection of HeLa human cervical cancer cells (day 0). Additional rats served as healthy controls. Rats were either untreated, received SBRT to the T10-L6 vertebrae on day 14 (15 Gy, two fractions), DTX on day 7 or 14, or ZA on day 7. Rats were euthanized on day 21. Tumor burden was assessed with bioluminescence images acquired on day 14 and 21, histology of the excised T11 and L5 vertebrae, and ex-vivo μCT images of the T13-L4. Microstructural parameters (bone volume/total volume, trabecular number, spacing, thickness, and bone mineral density) were measured from L2 vertebrae. Load to failure was measured with axial compressive loading of the L1-L3 motion segments. Microdamage accumulation was labeled in T13 vertebrae with BaSO4 staining and was visualized with high resolution μCT imaging. Microdamage volume fraction was defined as the ratio of BaSO4 to bone volume. DTX administered on day 7 reduced tumor growth significantly (p < 0.05). Microdamage accumulation was found to be increased by the presence of metastases but was reduced by all treatments with ZA showing the largest improvement in HeLa cell injected rats. Load to failure was decreased in untreated and SBRT HeLa cell injected rats compared to healthy controls (p < 0.01). There was a moderate negative correlation between load to failure and microdamage volume fraction in vertebrae from rats injected with HeLa cells (R = -0.35, p = 0.031). Strong correlations were also found between microstructural parameters and load to failure and microdamage accumulation. Several factors, including the presence of osteolytic lesions and use of cancer therapies, influence microdamage accumulation and load to failure in rat vertebrae. Understanding the impact of these treatments on fracture risk of metastatic vertebrae is important to improve management of patients with spinal metastases.

SARS-CoV-2 antibodies and their neutralizing capacity against live virus in human milk after COVID-19 infection and vaccination: prospective cohort studies

BACKGROUND

There is limited understanding of the impact of coronavirus disease 2019 (COVID-19) infection and vaccination type and interval on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) human milk antibodies and their neutralizing capacity.

OBJECTIVES

These cohort studies aimed to determine the presence of antibodies and live virus neutralizing capacity in milk from females infected with COVID-19, unexposed milk bank donors, and vaccinated females and examine impacts of vaccine interval and type.

METHODS

Milk was collected from participants infected with COVID-19 during pregnancy or lactation (Cohort-1) and milk bank donors (Cohort-2) from March 2020-July 2021 at 3 sequential 4-wk intervals and COVID-19 vaccinated participants with varying dose intervals (Cohort-3) (January-October 2021). Cohort-1 and Cohort-3 were recruited from Sinai Health (patients) and through social media. Cohort-2 included Ontario Milk Bank donors. Milk was examined for SARS-CoV-2 antibodies and live virus neutralization.

RESULTS

Of females with COVID-19, 53% (Cohort-1, n = 55) had anti-SARS-CoV-2 IgA antibodies in ≥1 milk sample. IgA+ samples (40%) were more likely neutralizing than IgA- samples (odds ratio [OR]: 2.18; 95% confidence interval [CI]: 1.03, 4.60; P = 0.04); however, 25% of IgA- samples were neutralizing. Both IgA positivity and neutralization decreased ∼6 mo after symptom onset (0-100 compared with 201+ d: IgA OR: 14.30; 95% CI: 1.08, 189.89; P = 0.04; neutralizing OR: 4.30; 95% CI: 1.55, 11.89; P = 0.005). Among milk bank donors (Cohort-2, n = 373), 4.3% had IgA antibodies; 23% of IgA+ samples were neutralizing. Vaccination (Cohort-3, n = 60) with mRNA-1273 and shorter vaccine intervals (3 to <6 wk) resulted in higher IgA and IgG than BNT162b2 (P < 0.04) and longer intervals (6 to <16 wk) (P≤0.02), respectively. Neutralizing capacity increased postvaccination (P = 0.04) but was not associated with antibody positivity.

CONCLUSIONS

SARS-CoV-2 infection and vaccination (type and interval) impacted milk antibodies; however, antibody presence did not consistently predict live virus neutralization. Although human milk is unequivocally the best way to nourish infants, guidance on protection to infants following maternal infection/vaccination may require more nuanced messaging. This study was registered at clinicaltrials.gov as NCT04453969 and NCT04453982.

Impact of a peer-support programme to improve loneliness and social isolation due to COVID-19: does adding a secure, user friendly video-conference solution work better than telephone support alone? Protocol for a three-arm randomised clinical trial

INTRODUCTION

The COVID-19 pandemic has forced the implementation of physical distancing and self-isolation strategies worldwide. However, these measures have significant potential to increase social isolation and loneliness. Among older people, loneliness has increased from 40% to 70% during COVID-19. Previous research indicates loneliness is strongly associated with increased mortality. Thus, strategies to mitigate the unintended consequences of social isolation and loneliness are urgently needed. Following the Obesity-Related Behavioural Intervention Trials model for complex behavioural interventions, we describe a protocol for a three-arm randomised clinical trial to reduce social isolation and loneliness.

METHODS AND ANALYSIS

A multicentre, outcome assessor blinded, three-arm randomised controlled trial comparing 12 weeks of: (1) the HOspitals WoRking in Unity ('HOW R U?') weekly volunteer-peer support telephone intervention; (2) 'HOW R U?' deliver using a video-conferencing solution and (3) a standard care group. The study will follow Consolidated Standard of Reporting Trials guidelines.We will recruit 24-26 volunteers who will receive a previously tested half day lay-training session that emphasises a strength-based approach and safety procedures. We will recruit 141 participants ≥70 years of age discharged from two participating emergency departments or referred from hospital family medicine, geriatric or geriatric psychiatry clinics. Eligible participants will have probable baseline loneliness (score ≥2 on the de Jong six-item loneliness scale). We will measure change in loneliness, social isolation (Lubben social network scale), mood (Geriatric Depression Score) and quality of life (EQ-5D-5L) at 12-14 weeks postintervention initiation and again at 24-26 weeks.

ETHICS AND DISSEMINATION

Approval has been granted by the participating research ethics boards. Participants randomised to standard care will be offered their choice of telephone or video-conferencing interventions after 12 weeks. Results will be disseminated through journal publications, conference presentations, social media and through the International Federation of Emergency Medicine.

TRIAL REGISTRATION NUMBER

NCT05228782.

Predictors of later COVID-19 test seeking

Background

Delays in COVID-19 testing may increase the risk of secondary household and community transmission. Little is known about what patient characteristics and symptom profiles are associated with delays in test seeking.

Methods

We conducted a retrospective cohort study of all symptomatic patients diagnosed with COVID-19 and assessed in a COVID Expansion to Outpatients (COVIDEO) virtual care program between March 2020 and June 2021. The primary outcome was later test seeking more than 3 days from symptom onset. Multivariable logistic regression was used to examine predictors of later testing including patient characteristics and symptoms (30 individual symptoms or 7 symptom clusters).

Results

Of 5,363 COVIDEO patients, 4,607 were eligible and 2,155/4,607 (46.8%) underwent later testing. Older age was associated with increased odds of late testing (adjusted odds ratio [aOR] 1.007/year; 95% CI 1.00 to 1.01), as was history of recent travel (aOR 1.4; 95% CI 1.01 to 1.95). Health care workers had lower odds of late testing (aOR 0.50; 95% CI 0.39 to 0.62). Late testing was associated with symptoms in the cardiorespiratory (aOR 1.2; 95% CI 1.05, 1.36), gastrointestinal (aOR = 1.2; 95% CI 1.04, 1.4), neurological (aOR 1.1; 95% CI 1.003, 1.3) and psychiatric (aOR 1.3; 95% CI 1.1, 1.5) symptom clusters. Among individual symptoms, dyspnea, anosmia, dysgeusia, sputum, and anorexia were associated with late testing; pharyngitis, myalgia, and headache were associated with early testing.

Conclusion

Certain patient characteristics and symptoms are associated with later testing, and warrant further efforts to encourage earlier testing to minimize transmission.

Drivers of Emergency Department Use Among Oncology Patients in the Era of Novel Cancer Therapeutics: A Systematic Review

BACKGROUND

Patients diagnosed with cancer are frequent users of the emergency department (ED). While many visits are unavoidable, a significant portion may be potentially preventable ED visits (PPEDs). Cancer treatments have greatly advanced, whereby patients may present with unique toxicities from targeted therapies and are often living longer with advanced disease. Prior work focused on patients undergoing cytotoxic chemotherapy, and often excluded those on supportive care alone. Other contributors to ED visits in oncology, such as patient-level variables, are less well-established. Finally, prior studies focused on ED diagnoses to describe trends and did not evaluate PPEDs. An updated systematic review was completed to focus on PPEDs, novel cancer therapies, and patient-level variables, including those on supportive care alone.

METHODS

Three online databases were used. Included publications were in English, from 2012-2022, with sample sizes of ≥50, and reported predictors of ED presentation or ED diagnoses in oncology.

RESULTS

45 studies were included. Six studies highlighted PPEDs with variable definitions. Common reasons for ED visits included pain (66%) or chemotherapy toxicities (69.1%). PPEDs were most frequent amongst breast cancer patients (13.4%) or patients receiving cytotoxic chemotherapy (20%). Three manuscripts included immunotherapy agents, and only one focused on end-of-life patients.

CONCLUSION

This updated systematic review highlights variability in oncology ED visits during the last decade. There is limited work on the concept of PPEDs, patient-level variables and patients on supportive care alone. Overall, pain and chemotherapy toxicities remain key drivers of ED visits in cancer patients. Further work is needed in this realm.

Cost consequence analysis of Apathy in Dementia Methylphenidate Trial 2 (ADMET 2)

BACKGROUND

This paper used data from the Apathy in Dementia Methylphenidate Trial 2 (NCT02346201) to conduct a planned cost consequence analysis to investigate whether treatment of apathy with methylphenidate is economically attractive.

METHODS

A total of 167 patients with clinically significant apathy randomized to either methylphenidate or placebo were included. The Resource Utilization in Dementia Lite instrument assessed resource utilization for the past 30 days and the EuroQol five dimension five level questionnaire assessed health utility at baseline, 3 months, and 6 months. Resources were converted to costs using standard sources and reported in 2021 USD. A repeated measures analysis of variance compared change in costs and utility over time between the treatment and placebo groups. A binary logistic regression was used to assess cost predictors.

RESULTS

Costs were not significantly different between groups whether the cost of methylphenidate was excluded (F(2,330) = 0.626, ηp2 = 0.004, p = 0.535) or included (F(2,330) = 0.629, ηp2 = 0.004, p = 0.534). Utility improved with methylphenidate treatment as there was a group by time interaction (F(2,330) = 7.525, ηp2 = 0.044, p < 0.001).

DISCUSSION

Results from this study indicated that there was no evidence for a difference in resource utilization costs between methylphenidate and placebo treatment. However, utility improved significantly over the 6-month follow-up period. These results can aid in decision-making to improve quality of life in patients with Alzheimer's disease while considering the burden on the healthcare system.

Progression to malignancy in oral potentially malignant disorders: a retrospective study of 5,036 patients in Ontario, Canada

OBJECTIVES

Determine the rate of malignant transformation (MT) of oral potentially malignant disorders (OPMDs) and risk factors for transformation.

STUDY DESIGN

The OPMD database (2001-2015) from 2 biopsy services in Ontario, Canada, was linked to the Ontario Cancer Registry to determine the rate of progression to oral squamous cell carcinoma (OSCC). Clinical and histologic features of progressed and non-progressed cases were compared to determine risk factors for progression.

RESULTS

The MT rate was 6.4% (322/5,036 cases). The mean time for cancer development was 51.2 months. 33.6% of cases (107/322) progressed after over 60 months. The risk of cancer increased with age and was higher in non-smokers. The MT rate was highest in the tongue (11.4%), followed by the floor of mouth (7.1%) and gingiva (6.5%). Histologic grade was associated with progression to cancer (P < .0001). Atypical verrucous-papillary lesions with no or mild dysplasia predominantly affected older patients' gingiva, and the progression rate was significantly higher than conventional mild dysplasia (9.2% vs 3.2%, P = .0002).

CONCLUSIONS

Our population-based retrospective study showed that <10% of OPMDs progressed to cancer, which could take many years. Atypical papillary-verrucous proliferation without high-grade dysplasia is a subtype of OPMD requiring further study.

Lipopolysaccharide, Immune Biomarkers and Cerebral Amyloid-Beta Deposition in Older Adults With Mild Cognitive Impairment & Major Depressive Disorder

OBJECTIVE

Inflammatory activation and increased immune response to lipopolysaccharide occur in both depression and cognitive decline and may link these two conditions. We investigated whether lipopolysaccharide (LPS), LPS binding protein (LBP) and peripheral biomarkers of immune response were associated with increased cerebral deposition of amyloid-beta (Abeta) in older adults with mild cognitive impairment (MCI) and remitted major depressive disorder (rMDD).

DESIGN

Cross-sectional analysis.

SETTING

Five academic health centers in Toronto.

PARTICIPANTS

Older adults with MCI with/without rMDD.

MEASUREMENTS

We investigated the associations among serum LPS, LBP, biomarkers of inflammatory activation - Interleukin-6 (IL-6), C-reactive protein (CRP), monocyte chemoattractant protein-1 (MCP-1), and cerebral Abeta deposition quantified by positron emission tomography.

RESULTS

Among 133 study participants (82 with MCI and 51 with MCI+rMDD) there was no association between LPS (beta - 0.17, p = 0.8) or LBP (beta - 0.11, p = 0.12) and global deposition of Abeta following adjustment for age, gender, and APOE genotype in multivariable regression analyses. LBP was positively correlated with CRP (r = 0.5, p <0.001) and IL-6 (r = 0.2, p = 0.02) but no inflammatory biomarker was associated with Abeta deposition; rMDD was not associated with deposition of Abeta (beta -0.09, p = 0.22).

CONCLUSION

In this cross-sectional analysis, we did not find an association among LPS/LBP, immune biomarkers or rMDD and global deposition of Abeta. Future analyses should assess the longitudinal relationships between peripheral and central biomarkers of immune activation, depression and cerebral Abeta deposition.

Gene mutations as a non-invasive measure of adult cochlear implant performance: Variable outcomes in patients with select TMPRSS3 mutations

BACKGROUND

The cochlear implant (CI) has proven to be a successful treatment for patients with severe-to-profound sensorineural hearing loss, however outcome variance exists. We sought to evaluate particular mutations discovered in previously established sensory and neural partition genes and compare post-operative CI outcomes.

MATERIALS AND METHODS

Utilizing a prospective cohort study design, blood samples collected from adult patients with non-syndromic hearing loss undergoing CI were tested for 54 genes of interest with high-throughput sequencing. Patients were categorized as having a pathogenic variant in the sensory partition, pathogenic variant in the neural partition, pathogenic variant in both sensory and neural partition, or with no variant identified. Speech perception performance was assessed pre- and 12 months post-operatively. Performance measures were compared to genetic mutation and variant status utilizing a Wilcoxon rank sum test, with P<0.05 considered statistically significant.

RESULTS

Thirty-six cochlear implant patients underwent genetic testing and speech understanding measurements. Of the 54 genes that were interrogated, three patients (8.3%) demonstrated a pathogenic mutation in the neural partition (within TMPRSS3 genes), one patient (2.8%) demonstrated a pathogenic mutation in the sensory partition (within the POU4F3 genes). In addition, 3 patients (8.3%) had an isolated neural partition variance of unknown significance (VUS), 5 patients (13.9%) had an isolated sensory partition VUS, 1 patient (2.8%) had a variant in both neural and sensory partition, and 23 patients (63.9%) had no mutation or variant identified. There was no statistically significant difference in speech perception scores between patients with sensory or neural partition pathogenic mutations or VUS. Variable performance was found within patients with TMPRSS3 gene mutations.

CONCLUSION

The impact of genetic mutations on post-operative outcomes in CI patients was heterogenous. Future research and dissemination of mutations and subsequent CI performance is warranted to elucidate exact mutations within target genes providing the best non-invasive prognostic capability.

Predicting Patterns of Distant Metastasis in Breast Cancer Patients following Local Regional Therapy Using Machine Learning

Up to 30% of breast cancer (BC) patients will develop distant metastases (DM), for which there is no cure. Here, statistical and machine learning (ML) models were developed to estimate the risk of site-specific DM following local-regional therapy. This retrospective study cohort included 175 patients diagnosed with invasive BC who later developed DM. Clinicopathological information was collected for analysis. Outcome variables were the first site of metastasis (brain, bone or visceral) and the time interval (months) to developing DM. Multivariate statistical analysis and ML-based multivariable gradient boosting machines identified factors associated with these outcomes. Machine learning models predicted the site of DM, demonstrating an area under the curve of 0.74, 0.75, and 0.73 for brain, bone and visceral sites, respectively. Overall, most patients (57%) developed bone metastases, with increased odds associated with estrogen receptor (ER) positivity. Human epidermal growth factor receptor-2 (HER2) positivity and non-anthracycline chemotherapy regimens were associated with a decreased risk of bone DM, while brain metastasis was associated with ER-negativity. Furthermore, non-anthracycline chemotherapy alone was a significant predictor of visceral metastasis. Here, clinicopathologic and treatment variables used in ML prediction models predict the first site of metastasis in BC. Further validation may guide focused patient-specific surveillance practices.

Randomized trial of personalized psychological feedback from a longitudinal online survey and simultaneous evaluation of randomized stepped wedge availability of in-person peer support for hospital staff during the COVID-19 pandemic

OBJECTIVE

We tested if automated Personalized Self-Awareness Feedback (PSAF) from an online survey or in-person Peer Resilience Champion support (PRC) reduced emotional exhaustion among hospital workers during the COVID-19 pandemic.

METHOD

Among a single cohort of participating staff from one hospital organization, each intervention was evaluated against a control condition with repeated measures of emotional exhaustion at quarterly intervals for 18 months. PSAF was tested in a randomized controlled trial compared to a no-feedback condition. PRC was tested in a group-randomized stepped-wedge design, comparing individual-level emotional exhaustion before and after availability of the intervention. Main and interactive effects on emotional exhaustion were tested in a linear mixed model.

RESULTS

Among 538 staff, there was a small but significant beneficial effect of PSAF over time (p = .01); the difference at individual timepoints was only significant at timepoint three (month six). The effect of PRC over time was non-significant with a trend in the opposite direction to a treatment effect (p = .06).

CONCLUSIONS

In a longitudinal assessment, automated feedback about psychological characteristics buffered emotional exhaustion significantly at six months, whereas in-person peer support did not. Providing automated feedback is not resource-intensive and merits further investigation as a method of support.

A comparison of tertiary level NICU costs for infants born <1250 g supplemented with human versus bovine milk-based fortifiers

BACKGROUND

Human milk-based fortifiers (HMBF) are more costly than bovine milk-based fortifiers (BMBF); but, the efficacy of human or bovine fortification for infants born <1250 g has yet to be fully elucidated. Our objective was to determine the effect of fortifier source on tertiary neonatal costs.

METHODS

Costs associated with tertiary neonatal care, including direct and indirect hospital expenditures, feed-related costs and physician billing were analysed retrospectively for participants of OptiMoM (NCT02137473), a blinded RCT comparing fortifier type for babies born <1250 g. A generalized linear model of cost according to fortifier type was created.

RESULTS

Mean [95% confidence interval] daily costs per patient, adjusted for birth gestation and weight, was significantly greater in the human than the BMBF group ($3,452 [$3,186 - $3,740] Canadian dollars (CAD) versus $2,451 [$2,257 - $2,662] CAD) respectively, p < 0.0001).

CONCLUSION

HMBF usage entails additional costs on NICU stay that should be considered with implementation.

Are We Overoperating on Isolated Orbital Floor Fractures?

BACKGROUND

Orbital floor fracture defect size and inferior rectus (IR) rounding index are currently accepted indications for surgery to prevent late enophthalmos. The authors analyzed the positive predictive value (PPV) of these indications.

METHODS

Twenty-eight patients with orbital floor fractures presenting without enophthalmos underwent Hertel exophthalmometry at presentation and at weeks 1, 2, 3, 6, 13, 26, and 52 or more after injury. Orbital defect size and IR rounding index were measured from computed tomographic scans, and PPVs of defects of 1.5 to 2 cm 2 or larger and IR rounding index of 1 or higher for enophthalmos (≥2 mm) were calculated.

RESULTS

Nineteen patients had isolated orbital floor fractures (group A), three had noncontinuous orbital floor and medial wall fractures (group B), and six had continuous orbital floor with medial wall fractures (group C). Mean follow-up time was 440 days. Of all patients, 20 had a defect size of 1.5 cm 2 or larger, 12 had a defect of 2.0 cm 2 or larger, and 13 had an IR rounding index of 1 or higher. Of the 28 patients, only one from group A and two from group C developed enophthalmos of 2 mm only. The PPVs of orbital floor defect size of 1.5 cm 2 or larger and 2 cm 2 or larger (groups A and B only) for late enophthalmos were 6.7% and 0%, respectively. The PPV of IR rounding index of 1 or higher for late enophthalmos (all groups) was 0%.

CONCLUSIONS

For patients with orbital floor fractures presenting without enophthalmos, defects of 1.5 cm 2 or larger and 2 cm 2 or larger, and IR rounding index of 1 or higher, are weakly predictive of late enophthalmos. Furthermore, patients who do not develop enophthalmos within 3 weeks of injury are unlikely to develop significant (>2 mm) late enophthalmos.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Prevalence and predictors for being unscreened for diabetic retinopathy: a population-based study over a decade

OBJECTIVE

To determine the population-level predictors for being unscreened for diabetic retinopathy (DR) among individuals with diabetes in a developed country.

DESIGN

A retrospective population-based repeated-cross-sectional study.

PARTICIPANTS

All individuals with diabetes (types 1 and 2) aged ≥20 years in the universal health care system in Ontario were identified in the 2011-2013 and 2017-2019 time periods.

METHODS

The Mantel-Haenszel test was used for the relative risk (RR) comparison of subcategories stratified by the 2 cross-sectional time periods.

RESULTS

A total of 1 145 645 and 1 346 578 individuals with diabetes were identified in 2011-2013 and 2017-2019, respectively. The proportion of patients unscreened for DR declined very slightly from 35% (n = 405 967) in 2011-2013 to 34% (n = 455 027) in 2017-2019 of the population with diabetes (RR = 0.967; 95% CI, 0.964-0.9693; p < 0.0001). Young adults aged 20-39 years of age had the highest proportion of unscreened patients (62% and 58% in 2011-2013 and 2017-2019, respectively). Additionally, those who had a lower income quintile (RR = 1.039; 95% CI, 1.036-1.044; p < 0.0001), were recent immigrants (RR = 1.286; 95% CI, 1.280-1.293; p < 0.0001), lived in urban areas (RR = 1.149; 95% CI, 1.145-1.154; p < 0.0001), had a mental health history (RR = 1.117; 95% CI, 1.112-1.122; p < 0.0001), or lacked a connection to a primary care provider (RR = 1.656; 95% CI, 1.644-1.668; p < 0.0001) had a higher risk of being unscreened.

CONCLUSIONS

This population-based study suggests that over 1 decade, 33% of individuals with diabetes are unscreened for DR, and young age, low income, immigration, residing in a large city, mental health illness, and no primary care access are the main predictors.

Characterizing PRN Use of Psychotropic Medications for Acute Agitation in Canadian Long-Term Care Residents with Dementia Before and During COVID-19

Background

Agitation is a disabling neuropsychiatric symptom of dementia. Pro re nata (PRN) injections of psychotropics can be administered for severe acute agitation, but little is known about the frequency of their actual use.

Objective

Characterize actual use of injectable PRN psychotropics for severe acute agitation in Canadian long-term care (LTC) residents with dementia and compare use before and during the COVID-19 pandemic.

Methods

Residents from two Canadian LTC facilities with orders for PRN haloperidol, olanzapine, or lorazepam between January 1, 2018- May 1, 2019 (i.e., pre-COVID-19) and January 1, 2020- May 1, 2021 (i.e., COVID-19) were identified. Electronic medical records were reviewed to document PRN injections of psychotropic medications and collect data on reason and demographic characteristics. Descriptive statistics were used to characterize frequency, dose, and indications of use, and multivariate regression models were used to compare use between time periods.

Results

Of the 250 residents, 45 of 103 (44%) people in the pre-COVID-19 period and 85 of 147 (58%) people in the COVID-19 period with standing orders for PRN psychotropics received ≥1 injections. Haloperidol was the most frequently used agent in both time periods (74% (155/209 injections) pre-COVID-19; 81% (323/398 injections) during COVID-19). Residents in the COVID-19 period were almost two times more likely to receive injections compared with those in the pre-COVID-19 period (odds ratio = 1.96; 95% CI = 1.15-3.34; p = 0.01).

Conclusion

Our results suggest that use of PRN injections increased in LTC during the pandemic and contribute to the mounting evidence that agitation worsened during that time.

Tranexamic acid for the prevention of postpartum haemorrhage: the TAPPH-1 pilot randomized trial and lessons learned for trials in Canadian obstetrics

Postpartum haemorrhage (PPH) is a leading cause of maternal morbidity and mortality. While tranexamic acid (TXA) reduces bleeding and transfusion requirements in established PPH, we sought to determine the feasibility of conducting a fully powered trial assessing the effect of prophylactic tranexamic acid, prior to PPH onset, in a Canadian Obstetric setting. With institutional and Health Canada approval, consenting, eligible parturients (singleton, > 32 weeks gestation, vaginal or caesarian delivery) were randomly assigned to receive TXA (1 g intravenously) or placebo (0.9% saline) prior to delivery. Participants, investigators, data collectors/adjudicators, and analysis was blinded. The primary outcome was administration of study intervention to > 85% of randomized individuals. Secondary outcomes included recruitment rate (feasibility) and safety outcomes. Over 8 months, 611 were approached, 35 consented, and 27 randomized (14 TXA, 13 placebo). 89% of randomized participants received the assigned intervention. Recruitment fell below feasibility (23% target). No serious adverse outcomes occurred. Our pilot trial in a Canadian Obstetric setting was unable to demonstrate feasibility to conduct a large, multicentre trial to examine prophylactic use of tranexamic for PPH secondary to the complex regulatory requirements associated with a trial for an off-label, but commonly utilized intervention. These challenges should inform stakeholders on the resources and challenges of conducting future trials using off-label interventions.Trial registration: www.clinicaltrials.gov , NCT03069859 (03/03/2017).

Amyloid-PET of the white matter: Relationship to free water, fiber integrity, and cognition in patients with dementia and small vessel disease

White matter (WM) injury is frequently observed along with dementia. Positron emission tomography with amyloid-ligands (Aβ-PET) recently gained interest for detecting WM injury. Yet, little is understood about the origin of the altered Aβ-PET signal in WM regions. Here, we investigated the relative contributions of diffusion MRI-based microstructural alterations, including free water and tissue-specific properties, to Aβ-PET in WM and to cognition. We included a unique cohort of 115 participants covering the spectrum of low-to-severe white matter hyperintensity (WMH) burden and cognitively normal to dementia. We applied a bi-tensor diffusion-MRI model that differentiates between (i) the extracellular WM compartment (represented via free water), and (ii) the fiber-specific compartment (via free water-adjusted fractional anisotropy [FA]). We observed that, in regions of WMH, a decrease in Aβ-PET related most closely to higher free water and higher WMH volume. In contrast, in normal-appearing WM, an increase in Aβ-PET related more closely to higher cortical Aβ (together with lower free water-adjusted FA). In relation to cognitive impairment, we observed a closer relationship with higher free water than with either free water-adjusted FA or WM PET. Our findings support free water and Aβ-PET as markers of WM abnormalities in patients with mixed dementia, and contribute to a better understanding of processes giving rise to the WM PET signal.

Boswellic Acids Improve Clinical Cognitive Scores and Reduce Systemic Inflammation in Patients with Mild to Moderate Alzheimer's Disease

BACKGROUND

Recent therapeutic approaches for Alzheimer's disease (AD) have had limited success. Considering the association of neuroinflammation with AD symptoms as demonstrated in multiple studies, assessment of the clinical efficacy of molecules that reduce systemic or brain inflammation is warranted.

OBJECTIVE

This clinical trial assessed whether boswellic acids can improve cognitive and neuropsychiatric symptoms while reducing inflammation in AD patients.

METHODS

A double-blind, placebo-controlled, study was conducted on 85 AD patients randomized to boswellic acids (K-Vie™ as the main ingredient in Memowell™) or placebo for 6 months. Clinical Dementia Rating-Sum of Boxes (CDR-SOB) and Mini-Mental State Examination (MMSE) scores were compared to baseline and between groups and constituted the co-primary clinical efficacy endpoints. Secondary outcomes included neuropsychiatric assessment (Neuropsychiatric Inventory-Questionnaire, NPI-Q) and assessment of AD and inflammation biomarkers.

RESULTS

Patients on K-Vie™ showed a 3.1- and 1.6-unit improvement in MMSE and CDR-SOB scores, respectively, when compared to patients on placebo. NPI-Q analysis revealed significant improvement in the K-Vie™ but not in the placebo group. Only mild gastrointestinal side effects were reported in a few patients. Patients on K-Vie™ showed improvement in plasma AD biomarkers and reduction of key inflammatory cytokines including IL-6 and TNF.

CONCLUSION

Our results support the positive cognitive effects of boswellic acids by reducing the systemic inflammation.

A methylation-dependent checkpoint by SETD7 promotes myocardial ischemic injury in mice and men

Background

Despite appropriate revascularization strategies, a significant number of patients with myocardial infarction (MI) develop ischemic heart failure suggesting that breakthrough therapies are yet to be approved in this setting. Methylation of non-histone proteins is emerging as a central regulatory mechanism in health and disease. The methyltransferase SETD7 has been shown to methylate and alter the function of a variety of proteins in vitro, however, its function in the heart is poorly understood.

Purpose

To determine the role of SETD7 in myocardial ischemic injury.

Methods

Neonatal rat ventricular myocytes (NRVM) were exposed to normal glucose levels or glucose deprivation (GD) for 15 h, in the presence of the selective SETD7 inhibitor (R)-PFI-2 or its inactive enantiomer (S)-PFI-2. Western blot and real-time PCR were employed to investigate the effects of energy stress on SETD7 and the Hippo pathway, while apoptosis and oxidative stress were assessed by Caspase-3 activity assay and mitoSOX staining. YAP transcriptional activity was assessed by chromatin immunoprecipitation assay (ChIP) while its localization and methylation were examined by confocal microscopy and immunoblotting, respectively. SETD7 knockout (SETD7−/−) mice and wild-type (WT) littermates underwent myocardial ischemia-reperfusion (I/R) injury (1h coronary ligation /24 h of reperfusion) followed by assessment of cardiac function by echocardiography. Left ventricular (LV) myocardial samples were collected from I/R mice and patients with ischemic cardiomyopathy (ICM), and isolated cardiomyocytes were treated with (R)-PFI-2. Finally, SETD7 expression was also assessed in peripheral blood mononuclear cells (PBMCs) from patients with ST-elevation MI (STEMI).

Results

SETD7 was activated upon energy deprivation in cultured NRVMs and methylated YAP, leading to its cytosolic retention and impaired transcription of antioxidant genes MnSOD and CAT. Pharmacological inhibition of SETD7 by (R)-PFI-2 restored YAP nuclear localization thus preventing mitochondrial reactive oxygen species (mtROS) and apoptosis. SETD7 deletion in mice attenuated I/R injury, mtROS and LV dysfunction by restoring YAP-dependent transcriptional programs. SETD7/YAP dysregulation was also observed in LV specimens from ICM patients. Moreover, in cardiomyocytes isolated from I/R mice and ICM patients, (R)-PFI-2 restored YAP nuclear localization, prevented mtROS accumulation while improving myofibrillar protein contractility and Ca2+ sensitivity. Finally, SETD7 was upregulated in PBMCs from STEMI patients and negatively correlated with the expression of MnSOD and CAT.

Conclusions

SETD7-dependent methylation of YAP is an important mechanism underpinning myocardial oxidative stress and apoptosis during ischemia. Pharmacological modulation of SETD7 by (R)-PFI-2 may represent a potential therapeutic approach to prevent myocardial ischemic damage through modulation of the Hippo pathway.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): University of Zurich

Extension of fitness evaluations with muscle oxygen saturation measurements based on near-infrared spectroscopy analysis during cardiopulmonary exercise testing in elite athletes

Introduction

Many cardiovascular parameters of sport adaptation have become an area of detailed research in recent decades. However, details of local circulatory and metabolic processes ongoing in the working muscles during physical exercise need to be revealed.

Purpose

Our aim was to extend cardiopulmonary exercise testing with near-infrared spectroscopy measurements to focus on observing local changes in the contracting muscles during running.

Methods

Mixed muscle oxygen saturation values (SmO2) measured in the left vastus lateralis muscle of athletes were analyzed by near-infrared spectroscopy during vita maxima treadmill cardiopulmonary exercise testing with 2-min fingertip lactate measurements. Body composition analysis was carried out with bioimpedance method. One-way repeated measures ANOVA, Tukey post-hoc test, Shapiro–Wilk test and Pearson correlation were used for statistical analysis.

Results

The results of 66 elite athletes (male: 40; age: 17.9±3.6 y; training: 17.7±6.6 h/w; water polo player: 56, wrestler: 8, basketball player: 2) were analyzed. The 10-second averaged values of the measured saturation values were examined at rest (65.8±11.1%), at the anaerobic threshold (40.7±22.8%), at maximum load (30.2±20.5%) and after 5 minutes of cool-down (70.9±12.8%). Significant differences were measured between the four measurement time points in all pairings. A negative correlation was found between the achieved maximal oxygen uptake and the muscle oxygen saturation values measured at the anaerobic threshold and at the maximal load (respectively r=−0.30, p&lt;0.02; r=−0.32, p&lt;0.01). Oxygen uptake at the end of cool-down was also negatively correlated with muscle oxygen saturation values measured at the anaerobic threshold and at the peak of exercise (respectively r=−0.27, p&lt;0.05; r=−0.27, p&lt;0.05). The fat-free mass of the identical limb showed negative correlation with the muscle oxygen saturation values measured at the anaerobic threshold, at the maximal load and at the cool-down (respectively r=−0.43, p&lt;0.01; r=−0.44, p&lt;0.01; r=−0.35, p&lt;0.01), while positive interactions were observed between the body-fat mass of the same limb and the muscle oxygen saturation values (respectively r=0.51, p&lt;0.01; r=0.55, p&lt;0.01; r=0.41, p&lt;0.01). Muscle oxygen saturation values showed no significant correlations with exercise time, lactate levels, or heart rate measurements.

Conclusions

By our results, muscle oxygen saturation measurements can be reliably applied during exercise physiological measurements. During exercise, muscle oxygen saturation values negatively correlated with oxygen uptake. At the cool-down phase, a rebound effect could be observed compared to the resting measurements. On the identical limb, the higher the muscle mass was, the higher muscle desaturation could be measured. This easy-to-perform test provides insight into muscle metabolism processes and can help with training planning and athlete follow-up.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This project was supported by a grant from the National Research, Development and Innovation Office (NKFIH) of Hungary (K 135076). Supported by the ÚNKP-21-3-I-SE-68 New National Excellence Program of the Ministry for Innovation and Technology from the Source of the National Research, Development and Innovation fund.

Increased Tenascin-C expression contributes to cardiac dysfunction and fibrosis in Duchenne muscular dystrophy

Introduction and aims

Cardiac fibrosis is characterized by the net accumulation of extracellular matrix (ECM) proteins in the cardiac interstitium and contributes to cardiac contractile dysfunction. In Duchenne muscular dystrophy (DMD), cardiomyopathy develops as a result of a dystrophin deficiency causing fibrofatty replacement of the myocardium, however the underlying mechanisms are not fully understood. There is a growing collection of evidence that ECM proteins, including Tenascin C (TN-C), plays a maladaptive role in left ventricular (LV) remodelling and cardiac fibrosis in ischemic heart disease. The aims of our study were 1) to assess TN-C levels, fibrosis and cardiac dysfunction in DMD patients, and 2) to clarify the role of TN-C in cardiovascular dysfunction and fibrosis using male mdx (n=10) and mdx TN-C KO mice (n=8).

Results

In male patients with DMD (n=18) and age matched controls (n=12) undergoing cardiac MRI, we detected greater myocardial fibrosis than in control hearts. In addition, we observed an elevation of TN-C plasma levels [median concentration (3.55); interquartile range (0.61–7.43) ng/mL] in DMD patients, and its expression negatively correlated to LV ejection fraction (EF) [median LVEF (45); interquartile range (37.5–51.5) %]. Male wt, mdx and mdx TN-C KO age-matched (10 months) mice were used. Transthoracic echocardiography was performed and fibrosis was assessed on cardiac tissue sections. Wire myography was used to assess vascular endothelial function. To explore the signalling pathways contributing to cardiac fibrosis, human cardiac fibroblasts (hCFs) were treated with recombinant human TN-C or TGF-β and gene expression and epigenetic regulation of NF-kB/p65 were assessed. Mdx mice showed significantly increased cardiac fibrosis which was accompanied with markedly elevated TN-C level in cardiac tissue and plasma compared to wt animals (p&lt;0.05, respectively). Moreover, TN-C level in plasma correlated positively with the degree of cardiac dilation in dystrophic mice. In addition, vascular endothelial function was notably impaired in mdx mice. In contrast, we observed preserved vascular function in mdx- TN-C KO mice, this was accompanied by a significant reduction in cardiac fibrosis in compared to age-matched mdx mice (p&lt;0.05, respectively). hCFs treated with TN-C or TGF-β showed increased collagen and α-SMA expressions which could be prevented by application of siRNA against TN-C. In addition, both TN-C and TGF-β caused p65/NF-κB promoter demethylation and subsequently triggered pro-inflammatory and pro-fibrotic signalling, which could be reversed by applying p38 MAPK inhibitor in hCFs.

Conclusion

TN-C is a critical component of cardiac fibrosis and cardiac dysfunction in DMD. The activation of NF-κB p65 signalling pathway may play a role in TN-C induced fibrosis. Thus, TN-C may be a mediator and potential target for therapy in DMD-associated cardiovascular complications.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Österreichische MuskelforschungFWF - Austrian Science Found P 35878

Agomir of miRNA-30d – a potential new therapeutic target for prevention of ischemic cardiomyopathy after myocardial infarction?

Background

MicroRNA (miR)-30d is not only a valuable biomarker for assessing the extent of cardiac remodeling after myocardial infarction (MI), but also an important predictor of clinical outcome in heart failure. Overexpression of miRNA-30d appears to have a cardioprotective effect by preventing cardiomyocyte apoptosis as well as averting cardiac fibroblast proliferation via multiple molecular pathways. The aim of the present in vivo and in vitro study was to demonstrate whether an miR-30d can be a potential therapeutic target to reduce the risk of ischemic cardiomyopathy (iCMP) after MI.

Methods

First of all, miRNA profiling was performed by next generation sequencing (NGS) to assess differences in miRNA expression in ischemic vs. healthy myocardium in a rat model of MI using coronary artery ligation (ischemia/reperfusion injury, IR). MiR-30d was selected as the most promising target as it was significantly downregulated in ischemic myocardium and can be upregulated by cardioprotective agents. Therefore, an agomir of miR-30d was administered in the respective treatment group intraperitoneally, whereas non-functional, scrambled miRNA was administered in the control group. To analyze the ratio between phosphorylated p53 (pp53) and total p53, apoptosis was evaluated in human cardiomyocytes using a p53 and pp53 ELISA kit. To gain indirect insight into infarct healing, scratch assays were used to obtain information on cell migration in human umbilical vein endothelial cells (HUVEC) in vitro. Six weeks after the in vivo induction of acute MI/IR with consequential iCMP in a rat model, the extent of MI was evaluated by planimetry.

Results

The majority of miRNAs studied here showed significant up-regulation in the MI-induced heart tissue in comparison to the sham operated controls. In contrast, miRNA-30d was highly significantly reduced (p&lt;0.001). Based on these investigations and the already repeatedly documented cardioprotective effect of miR-30d overexpression, an agomir was selected as a potential therapy target. Human cardiomyocytes under the influence of an agomir of miR-30d showed a decreased pp53/total p53 ratio (0.66±0.09 vs. 0.81±0.19) and thus a distinct tendency (p=0.055) for a reduction in apoptotic rate compared to the control group. In HUVECs, gap closure was significantly faster in the agomir treated cells 20h and 26h post-scratching (19.1% more than scrambled control after 20h; p=0.0028 and 18.7% more than scrambled control after 26h; p=0.0081). In the in vivo model, infarct size of left ventricle was significantly reduced by using the agomir (7.43±4.13% vs. 12.76±4.76%; p=0.0172).

Conclusion

Using an agomir of miR-30d underlines the cardioprotective effects of miR-30d in MIR/IR and could reduce the risk for iCMP development. Further investigations regarding its therapeutic potential in the human should be considered, as microRNA treatments are gaining more and more clinical applicability today.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Paracelsus Medical University, PMU-FFF

Transcranial direct current stimulation leads to faster acquisition of motor skills, but effects are not maintained at retention

Practice is required to improve one’s shooting technique in basketball or to play a musical instrument well. Learning these motor skills may be further enhanced by transcranial direct current stimulation (tDCS). We aimed to investigate whether tDCS leads to faster attainment of a motor skill, and to confirm prior work showing it improves skill acquisition and retention performance. Fifty-two participants were tested; half received tDCS with the anode on primary motor cortex and cathode on the contralateral forehead while concurrently practicing a sequential visuomotor isometric pinch force task on Day 1, while the other half received sham tDCS during practice. On Day 2, retention of the skill was tested. Results from a Kaplan-Meier survival analysis showed that participants in the anodal group attained a pre-defined target level of skill faster than participants in the sham group (χ2 = 9.117, p = 0.003). Results from a nonparametric rank-based regression analysis showed that the rate of improvement was greater in the anodal versus sham group during skill acquisition (F(1,249) = 5.90, p = 0.016), but there was no main effect of group or time. There was no main effect of group or time, or group by time interaction when comparing performance at the end of acquisition to retention. These findings suggest anodal tDCS improves performance more quickly during skill acquisition but does not have additional benefits on motor learning after a period of rest.

A new Kirkpatrick-Baez-based scanning microscope for the Submicron Resolution X-ray Spectroscopy (SRX) beamline at NSLS-II

The development, construction, and first commissioning results of a new scanning microscope installed at the 5-ID Submicron Resolution X-ray Spectroscopy (SRX) beamline at NSLS-II are reported. The developed system utilizes Kirkpatrick-Baez mirrors for X-ray focusing. The instrument is designed to enable spectromicroscopy measurements in 2D and 3D with sub-200 nm spatial resolution. The present paper focuses on the design aspects, optical considerations, and specifics of the sample scanning stage, summarizing some of the initial commissioning results.

Outcomes of prolonged mechanical ventilation and tracheostomy in critically ill elderly patients: a historical cohort study

PURPOSE

With an aging global population, the increased proportion of elderly patients in the intensive care unit (ICU) raises important questions regarding optimal management. Currently, data on tracheostomy and its outcomes in the elderly are limited. We aimed to determine the in-hospital survival of elderly ICU patients following tracheostomy, and describe impacts on discharge disposition and functional outcomes.

METHODS

We conducted a historical cohort study at two academic hospitals in Toronto. All patients aged ≥ 70 yr who received a tracheostomy during their ICU stay between January 2010 and June 2016 were included in a retrospective chart review. Data on patient demographics, frailty, tracheostomy indication, and outcomes were collected.

RESULTS

The study included 270 patients with a mean (standard deviation) age of 81 (6) yr. The majority were admitted to ICU for respiratory failure (147/270, 54%) and received a tracheostomy for prolonged mechanical ventilation (202/270, 75%). Intensive care unit and hospital mortality were 26% (68/270) and 46% (125/270), respectively. Twenty-five percent (67/270) of patients were decannulated during hospital admission, a median [interquartile range (IQR)] of 41 [25-68] days after tracheostomy. Intensive care unit and hospital length of stay were 31 [17-53] and 81 [46-121] days, respectively. At hospital discharge, 6% (17/270) of patients were discharged home, all were frail (median Clinical Frailty Score of 7) and most were tube-fed (101/270, 70%), unable to speak (81/270, 56%), and nonambulatory (98/270, 68%).

CONCLUSIONS

In patients aged ≥ 70 yr, tracheostomy during ICU stay marked a transition toward prolonged chronic critical illness. Nearly half of the patients died during the admission, and although a quarter were successfully decannulated, the majority of survivors were left with severe frailty and functional impairment.

Vascular burden and cognition: Mediating roles of neurodegeneration and amyloid PET

It remains unclear to what extent cerebrovascular burden relates to amyloid beta (Aβ) deposition, neurodegeneration, and cognitive dysfunction in mixed disease populations with small vessel disease and Alzheimer's disease (AD) pathology. In 120 subjects, we investigated the association of vascular burden (white matter hyperintensity [WMH] volumes) with cognition. Using mediation analyses, we tested the indirect effects of WMH on cognition via Aβ deposition (¹⁸ F-AV45 positron emission tomography [PET]) and neurodegeneration (cortical thickness or ¹⁸ F fluorodeoxyglucose PET) in AD signature regions. We observed that increased total WMH volume was associated with poorer performance in all tested cognitive domains, with the strongest effects observed for semantic fluency. These relationships were mediated mainly via cortical thinning, particularly of the temporal lobe, and to a lesser extent serially mediated via Aβ and cortical thinning of AD signature regions. WMH volumes differentially impacted cognition depending on lobar location and Aβ status. In summary, our study suggests mainly an amyloid-independent pathway in which vascular burden affects cognitive function via localized neurodegeneration. HIGHLIGHTS: Alzheimer's disease often co-exists with vascular pathology. We studied a unique cohort enriched for high white matter hyperintensities (WMH). High WMH related to cognitive impairment of semantic fluency and executive function. This relationship was mediated via temporo-parietal atrophy rather than metabolism. This relationship was, to lesser extent, serially mediated via amyloid beta and atrophy.

Association between depression, gender and Alzheimer's neuropathology in older adults without dementia

OBJECTIVES

Previous studies regarding the relationship between depression and Alzheimer's neuropathology in older adults without dementia have reported conflicting findings. This study examined whether depression is associated with Alzheimer's neuropathology and whether sex moderates these relationships.

METHODS

This is a cross-sectional study of older adults without dementia (normal cognition or mild cognitive impairment, age 50+; CDR ≤ 0.5) who had autopsy within 1 year of their last clinic visit in the National Alzheimer's Coordinating Center database (2005-2020). Logistic regression models were fitted to determine if a recent or remote history of depression was associated with amyloid spread beyond the neocortex measured by modified Thal phase score, density of amyloid plaques measured by CERAD score or tau neuropathology measured by modified Braak score. A moderator analysis was performed to determine if any of these associations were moderated by sex.

RESULTS

This study included 407 participants (96 Thal, 405 Braak, and 406 CERAD). Those who had recently active depression (within previous 2 years) but not remote depression only were more likely to have higher Thal phase score compared to those without a history of depression (OR = 3.74; 95% CI, 1.15-12.17; p = 0.028). Sex did not moderate this association. No significant associations between recent depression and Braak or CERAD scores were observed.

CONCLUSION

Our findings indicate that the association between late life depression and Alzheimer's neuropathology is associated with spread of amyloid pathology beyond the neocortex to include allocortical and subcortical regions critical for regulation of mood and motivated behavior.

Mid-Infrared Imaging Characterization to Differentiate Lung Cancer Subtypes

Introduction: Lung cancer is the most common malignancy worldwide. Squamous cell carcinoma (SQ) and adenocarcinoma (LUAD) are the two most frequent histological subtypes. Small cell carcinoma (SCLC) subtype has the worst prognosis. Differential diagnosis is essential for proper oncological treatment. Life science associated mid- and near-infrared based microscopic techniques have been developed exponentially, especially in the past decade. Vibrational spectroscopy is a potential non-destructive approach to investigate malignancies.

Aims: Our goal was to differentiate lung cancer subtypes by their label-free mid-infrared spectra using supervised multivariate analyses.

Material and Methods: Formalin-fixed paraffin-embedded (FFPE) samples were selected from the archives. Three subtypes were selected for each group: 10-10 cases SQ, LUAD and SCLC. 2 μm thick sections were cut and laid on aluminium coated glass slides. Transflection optical setup was applied on Perkin-Elmer infrared microscope. 250 × 600 μm areas were imaged and the so-called mid-infrared fingerprint region (1800-648cm⁻¹) was further analysed with linear discriminant analysis (LDA) and support vector machine (SVM) methods.

Results: Both “patient-based” and “pixel-based” approaches were examined. Patient-based analysis by using 3 LDA models and 2 SVM models resulted in different separations. The higher the cut-off value the lower is the accuracy. The linear C-support vector classification (C-SVC) SVM resulted in the best (100%) accuracy for the three subtypes using a 50% cut-off value. The pixel-based analysis gave, similarly, the linear C-SVC SVM model to be the most efficient in the statistical indicators (SQ sensitivity 81.65%, LUAD sensitivity 82.89% and SCLC sensitivity 88.89%). The spectra cut-off, the kernel function and the algorithm function influence the accuracy.

Conclusion: Mid-Infrared imaging could be used to differentiate FFPE lung cancer subtypes. Supervised multivariate tools are promising to accurately separate lung tumor subtypes. The long-term perspective is to develop a spectroscopy-based diagnostic tool, revolutionizing medical differential diagnostics, especially cancer identification.

Human milk nutrient fortifiers alter the developing gastrointestinal microbiota of very-low-birth-weight infants

Nutrient fortifiers are added to human milk to support the development of very-low-birth-weight infants. Currently, bovine-milk-based fortifiers (BMBFs) are predominantly administered, with increasing interest in adopting human-milk-based fortifiers (HMBFs). Although beneficial for growth, their effects on the gastrointestinal microbiota are unclear. This triple-blind, randomized clinical trial (NCT02137473) tested how nutrient-enriching human milk with HMBF versus BMBF affects the gastrointestinal microbiota of infants born < 1,250 g during hospitalization. HMBF-fed infants (n = 63, n = 269 stools) showed lower microbial diversity, altered microbial community structure, and changes in predicted microbial functions compared with BMBF-fed infants (n = 56, n = 239 stools). HMBF-fed infants had higher relative and normalized abundances of unclassified Enterobacteriaceae and lower abundances of Clostridium sensu stricto. Post hoc analyses identified dose-dependent relationships between individual feed components (volumes of mother's milk, donor milk, and fortifiers) and the microbiota. These results highlight how nutrient fortifiers impact the microbiota of very-low-birth-weight infants during a critical developmental window.

Lipid Peroxidation as a Marker of Apathy and Executive Dysfunction in Patients at Risk for Vascular Cognitive Impairment

Background: The co-occurrence of apathy and executive dysfunction, a correlate of vascular cognitive impairment (VCI), is highly prevalent, yet facilitating factors are largely unknown. Objective: This study investigates the relationship between lipid peroxidation, apathy, and executive dysfunction in patients at risk for VCI. Methods: In participants with coronary artery disease, who are at a high risk of VCI, apathy (Apathy Evaluation Scale), and executive function (composite z-score based on age and education population norms from trails making test B, animal naming, and phonemic fluency tests) were assessed. Serum concentrations of an early (lipid hydroperoxide (LPH)) and late (8-isoprostane (8-ISO)) lipid peroxidation marker, were measured and the 8-ISO/LPH ratio was calculated. Results: Participants (n = 206, age±SD = 63.0±7.5, 80% men, total years of education = 15.9±3.4, AES score = 28.3±8.8, executive function = 0±1) demonstrated significantly different 8-ISO/LPH ratios between groups (F(3, 202) = 10.915, p <  0.001) with increasing levels in the following order: no apathy or executive dysfunction, only executive dysfunction (executive function composite score≤–1), only apathy (AES≥28), and both apathy and executive dysfunction. A model adjusting for demographics showed that lipid peroxidation was associated with both apathy (B(SE) = 4.63 (0.954), t = 4.852, p <  0.001) and executive function (B(SE) = –0.19 (0.079), t = –2.377, p = 0.018). However, when controlling for both demographics and vascular risk factors, lipid peroxidation was associated with only apathy (B(SE) = 3.11 (0.987), t = 3.149, p = 0.002). Conclusion: The results highlight a potentially important involvement of lipid peroxidation in the co-occurrence of apathy and executive dysfunction in those at risk for VCI.

Early Breast Milk Volumes and Response to Galactogogue Treatment

The aim of this study was to evaluate the effect of galactogogue management in mothers of very preterm infants with varying breast milk volumes prior to initiating this treatment. Data were utilized from 90 women who participated in a trial employing domperidone. Three groups were formed according to their breast milk volumes (based on their infants’ birth weight) at the time of randomization and study entry to the trial protocol: (1) ≤100 mL/kg/d; (2) 101–200 mL/kg/d; and (3) ≥201 mL/kg/d. Breast milk volumes were evaluated at the 14- and 28-day study treatment periods. All three groups showed a significant volume increase and volume percent increase both at the 14-day measure and also the 28-day measure. Mothers who started in the two lower volume groups showed the greatest % volume change overall, with 356.2% in the ≤100 mL/kg/d and 106.1% in the 101–200 mL/kg/d groups, compared to those mothers in the higher group of ≥201 mL/kg/d, showing a change of 45.2%, where p = 0.001. Mothers producing varying low volumes were able to demonstrate an effect from the use of domperidone and increase their volumes as much as three-hundred-fold over 14- and 28-day study periods. However, those mothers whose volumes were ≤100 mL/kg/d continued to maintain low absolute milk volumes, putting these mothers at ongoing risk of ceasing lactation.

Ivabradine rescues vascular abnormalities in a mouse model of duchenne muscular dystrophy

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Fonds zur Förderung der wissenschaftlichen Forschung

Ivabradine rescues vascular abnormalities in a mouse model of muscular dystrophy

Background

Duchenne muscular dystrophy (DMD) is a rare genetic disorder that primarily affects boys, initiated by the absence of dystrophin and is mainly differentiated by skeletal muscle degeneration and cardiac dysfunction. However, recent studies have underlined the importance of vascular abnormalities such as augmented arterial stiffness and endothelial dysfunction in the progression of cardiac complications in DMD. Several pleiotropic effects of ivabradine have been identified, including the reduction of vascular complications in coronary artery and ischemic heart disease patients. Nevertheless, whether chronic ivabradine treatment could improve the vascular complications in DMD is largely unknown.

Methods

In this study, vascular abnormalities in both dystrophin and utrophin deficient (mdx-utr KO) mice were examined, a severe and progressive animal model of DMD. Mice (4-6 weeks old) were subjected to ivabradine (10 mg/kg/day in drinking water) or vehicle treatments for 3 to 4 weeks. At the end of the treatment, aorta and lung tissue were collected to assess the vascular reactivity by wire myograph and the activity of angiotensin-converting enzyme (ACE) activity was measured in lung tissue respectively.

Results

Comparable with DMD patients, mdx-utr KO mice also exhibit vascular abnormalities and cardiac fibrosis. Ivabradine-treated mice showed a significantly improved endothelium-dependent vasodilation (p&lt;0.05) and decreased vascular stiffness compared to vehicle-treated animals (p&lt;0.01). In addition, lung ACE activity was significantly reduced in the treated mice in comparison to the control group (p&lt;0.01) indicating less activation in the renin-angiotensin-aldosterone system, which causative plays role in the progression of vascular and cardiac dysfunction.

Conclusions

In conclusion, our study shows for the first time the beneficial effects of chronic ivabradine treatment on the progression of cardiac vascular complications in DMD and this may present a novel therapeutic approach. Further studies are needed to clarify the underling signalling mechanisms.

Topographical Mapping of the cardiac autonomic innervation for selective cardiac neuromodulation in pigs and rabbits using MicroCT

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020- EU H2020-EU.1.2.2. - FET Proactive

"NeuHeart" Nr. 824071

Background & Introduction

In recent years, Vagus Nerve Stimulation (VNS) has proved to be a potential therapeutic approach for the treatment of cardiovascular diseases, such as Heart Failure or atrial fibrillation [1]. However, the lack of specific anatomical knowledge of the cervical VN [2, 3] and thus, of the cardiac autonomic innervation aggravates the side effects of unselective cervical VNS.

Purpose

The goal of this study was to investigate the cardiac vagus nerve branches for selective cardiac VNS stimulation using micro-computed tomography (µCT) and 3D renderings.

Methods

Vagus nerve specimens (n= 11 pig nerves, n= 5 rabbit nerves) were harvested from the nodose ganglion down to the cardiac branches in domestic pigs and New Zealand White rabbits on both sides, and the cardiac autonomic innervation was mapped µCT and 3D renderings.

Results

Our results provide anatomical and topographical key features on the cervical and cardiac autonomic innervation including course of the cardiac branch, cardiac branching patterns, fascicle number, and size of the autonomic nerves. We also compared these aforementioned anatomical parameters between pigs and rabbits and highlighted key anatomical differences among individuals within pigs. In pigs, the cardiac branches were partly composed of both nerves even when they branched off the VN whereas in rabbits, the two nerves were completely separated and the cardiac branch was solely parasympathetic. Finally, we generated a 3D model of various parts of the VN specimen and compared them to images of the native nerves taken during VN dissection surgery.

Conclusions

Here we present an imaging approach to map the anatomy and topography of the cardiac Vagus Nerve for selective stimulation of cardiac VN branches. We also characterized the morphology of the VN, the sympathetic trunk (ST), and the cardiac branch (CB) at the level of the cardiac branching point to highlight the complex interplay between the nerves. Our data provide one possible reason for unwanted side effects of cervical VNS. However, future studies are required to broaden the knowledge in this specific research field of selective cardiac VNS.

Dapagliflozin alleviates left ventricular hypertrophy and cardiac dysfunction in mice

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Ludwig Boltzmann Institute for Cardiovascular Research

Introduction

Sodium glucose cotransporter 2 inhibitors (SGLT2i) are a class of oral antidiabetic drugs. Recent clinical trials demonstrated and proved the cardiovascular benefit of SGLT2i in patients suffering from ischemic heart disease. In addition, left ventricular hypertrophy (LVH) is associated with cardiovascular events and using SGLT2i alleviated LVH in diabetic patients. However, only few studies investigated the effect of SGLT2i on regression of LVH in absence of diabetes.

Aim of the study

This study aimed to investigate whether the SGLT2i Dapagliflozin (DAPA) could attenuate LVH and cardiac dysfunction in a mouse model of pressure overload-induced LVH.

Methods

Male C57BL/6J mice (body weight 20-25g) were used. LVH was induced surgically by transverse aortic constriction (TAC). DAPA (1 mg/kg bodyweight/day) was administered through drinking water. The animals were divided in four groups: Group 1 underwent TAC for eight weeks (n=8). Group 2 concomitantly received DAPA for eight weeks after TAC (n=5). Group 3 received DAPA for only two weeks (in week 7 and 8 after TAC, n=5) to clarify if DAPA treatment could alleviate LVH at a later timepoint. Group 4 served as a sham control group (no LVH, n=8). Cardiac function was assessed using transthoracic echocardiography and invasive LV hemodynamic measurements.

Results

TAC resulted in a significant reduction in LV ejection fraction (LVEF) and significant increase in heart weight to body weight ratio (HW/BW) compared to sham (p&lt;0.001). In addition, TAC mice showed a significant increase of LV systolic pressure and end-diastolic pressure compared to sham (p&lt;0.01). Both the LVEF and LV functional parameters were markedly improved in mice treated with DAPA for eight weeks (p&lt;0.05). LV mass decreased compared to the untreated group. More importantly, DAPA treatment for only two weeks also improved LVEF and alleviated LVH compared to untreated TAC mice (p&lt;0.05). Furthermore, we also found that mice with only two weeks of DAPA treatment showed a tendency to improve LV hemodynamics.

Conclusions

DAPA was cardioprotective in a mouse model of pressure overload-induced LVH in absence of diabetes. It improved LV contractile function and LVH. DAPA also alleviated LVH and induced LV regression. Our findings uncovered that the SGLT2i DAPA contributed to the regression of LVH and cardiac fibrosis. Thus, administration of SLGT2i may be a novel adjunct therapy to boost reverse remodeling e.g. in patients with elective cardiac surgery and hypertrophic cardiomyopathy.

Dissecting the progression of cardiac dysfunction in tumor-bearing mice

Funding Acknowledgements

Type of funding sources: None.

Background

Cancer patients undergoing heart-related complications result in high incidences of mortality. Nevertheless, it is still not fully understood whether localized tumors affect heart function prior to the onset of cachexia, hence, making the heart more vulnerable for functional abnormalities in later stages of the disease. In addition to analyse heart function, we focus on the expression BCL-2–associated athanogene 3 (BAG3), a co-chaperone protein and Hsp70, which are highly expressed in tumor but decrease in cardiomyocytes (CM) in heart failure (HF).

Methods

Colon-26 adenocarcinoma cells (C26; n=22) with/without shIL-6 (C26 shIL-6; n=22) were injected subcutaneously into the right flank of 10-11 weeks old BALB/c male mice. Control mice were injected with vehicle (PBS; n=8). Cardiac function was assessed by echocardiography and invasive hemodynamic measurements 10 (early) and 20 (late) days after the injection, respectively. In addition, the expression of BAG3 and Hsp70 were determined by Western blot as well as the extend of cardiac fibrosis was determined by Masson-Goldner's trichrome staining.

Results

The tumor size was comparable between the two injected groups. However, only C26 group showed a significant loss of subcutaneous fat and skeletal muscle (p&lt;0.05, respectively), suggesting cachexia. Heart weight normalized to tibia length was not changed in the injected groups as compared to controls (day 20). However, left ventricular ejection fraction (LVEF) showed a tendency to decline in the early phase (p~0.08) in both injected group and it reached significance at late stage (p&lt;0.05). Invasive hemodynamic assessment also confirmed the contractile dysfunction, resulting in a decrease in LV systolic pressure and increase of LV end-diastolic pressure (p&lt;0.05, respectively). Importantly, these functional changes in the heart in tumor-bearing mice were associated with a marked reduction in both BAG3 and Hsp70 in the myocardium. Furthermore,  there was no sign of cardiac fibrosis in the injected groups.

Discussion

Our study shows for the first time that tumor rather than cancer cachexia plays a significant maladaptive role in the progression of cardiac dysfunction in a mouse model of C26 injection-induced cachexia. The progression of cardiac contractile dysfunction was associated with a decline in BAG3 and Hsp70 in tumor-bearing mice, suggesting changes of BAG3/Hsp 70 signalling may be a critical component as well as target.

St Thomas Hospital polarizing cold cardioplegia does not have superior effects on hemodynamic parameters in an infarcted rat model

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Orphan Drugs

Background

The use of cardioplegic solutions is indispensable during cardiac arrest in order to reduce myocardial metabolism and oxygen demand. Most commonly, hypothermic hyperkalemic cardioplegic solutions are used for open heart surgery. However, high potassium concentrations have several effects that limit left ventricular recovery, such as intracellular calcium overload resulting in the loss of contractility and increased cell death. Recently, we have shown that polarized cardiac arrest results in similar myocardial protection and improves cardiac functional recovery in a porcine model of cardiopulmonary bypass.

Purpose

The purpose of this study was to identify and compare the hemodynamic effects of cold St Thomas’ Hospital polarizing cardioplegia (STH-Pol) in contrast to standard St Thomas’ Hospital cardioplegia (STH2) in rats with chronic myocardial infarction. We hypothesize that St Thomas’ Hospital polarizing cardioplegia shows superior protection on left ventricular hemodynamic recovery as compared to standard STH2 cardioplegia.

Methods

Permanent myocardial infarction was induced by permanent occlusion of the left anterior descending artery LAD on Sprague-Dawley rats (593 ± 65g, day of sacrifice). Six weeks post-MI, after echocardiography assessment, the animals were sacrificed, and hemodynamic parameters were measured in an erythrocyte-perfused isolated heart model (STH2, control group: n=5 or STH-Pol, study group: n=4). Fifteen minutes of Langendorff mode and 30 minutes of Working-heart mode were followed by cardiac arrest with the two types cardioplegia (was applied three times every 20 minutes (t1= 0, t2= 20, t3= 40)). STH-Pol, consisting of esmolol, adenosine and magnesium, was mixed with erythrocyte-buffer shortly prior to administration (1:4). After ischemia, the hearts were started with a hot shot with warm erythrocyte-buffer. Hemodynamic parameters were measured every five minutes in Langendorff mode and Working-heart mode. Finally, pump function was examined and tissue samples were taken for analysis of troponin-T and high-energy phosphates. Results will be given as % of preischemic baseline value.

Results

The use of STH-Pol instead of STH2 did not yield any significant differences in hemodynamic recovery (%) across the parameters of left atrial flow (LAF: 40.87 ± 13.22 vs. 53.24 ± 11.27), coronary flow (CF: 58 ± 14.36 vs. 76.21 ± 9) and cardiac output (CO: 42.82 ± 13.36 vs. 51.83 ± 11.76). Furthermore, we have not been able to identify superior effects of STH-Pol on stroke volume (SV: 46.55 ± 13.91 vs. 52.66 ± 11.33) recovery. Moreover, heart rate was comparable in both groups (92.07 ± 2.02 vs. 99.35 ± 1.72), which indicates swift reversal of negative chronotropic effects of esmolol.

Conclusion

Polarizing cardioplegic arrest does not show superior effects on hemodynamic parameters of left ventricular recovery after ischemia in chronically infarcted rat hearts as compared to depolarizing cardioplegic arrest.

Stromal Vascular Fraction-based patches generated under perfusion culture enhance cardiac function in rats with chronic myocardial infarction

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss National Foundation

The development of novel adjuvant angiogenic therapies to restore the low-perfused microvascular network upon myocardial infarction (MI) is crucial to avoid a possible end-stage heart failure. Of the current adult cell-based therapies, human adipose tissue-derived stromal vascular fraction cell (SVF) has vast reparative potential, principally due to: 1) its heterogeneous composition rich in mesenchymal stem cells (MSC), endothelial cells (EC), pericytes and hematopoietic cells, among others. In vitro engineering of SVF-based patches under unidirectional flow, applied by the help of a perfusion-based bioreactor, was found to increase certain cellular SVF subgroups such as pericytes, compared to static culture. In this study, we aimed at studying the potential of SVF-based engineered tissues in a model of chronic MI in nude rats. Human SVF cells were isolated upon liposuction and cultured on 3D collagen sponges (8 mm diameter, 3 mm thickness) either under constant unidirectional perfusion or in static condition for 5 days. Patches were characterized in terms of cellular composition prior to implantation. MI was induced by permanent ligation of the left anterior descending (LAD) coronary artery in male nude rats. Cardiac MRI was performed 4 weeks after MI; prior to the suture of patches and before sacrifice (4 weeks after implantation). Left ventricular ejection fraction (EF) was the surrogate marker and primary end point for cardiac pump function. Controls included untreated MI animals. Following perfusion culture, SVF cells were composed with a statistically superior percentage of pericytes, identified as CD45- CD34- CD146+ compared to static culture (28.06±10.03 and 3.37±2.50, respectively, p&lt;0.0007). The presence of other cell subpopulations was similar in the patches generated in perfusion or static culture. While the percentage of EF at the time of sacrifice resulted to be not statistically different between static and perfusion-based patches, statically generated constructs showed a general trend of decrease in the % EF before and after treatment (rat 1: 61.96 vs 52.90; rat 2: 55.39 vs 53.00; rat 3: 52.34 vs 50.62, respectively). Perfusion-cultured patches, instead, rather improved the cardiac function, measured as % EF (rat 1: 51.82 vs 58.72; rat 2: 51.66 vs 60.45; rat 3: 53.50 vs 52. 36, respectively for 4 weeks following MI and 4 weeks following treatment). When comparing the ratio of the % EF 8 weeks and 4 weeks between static or perfusion-based patches and the untreated controls, rats treated with patches generated under perfusion resulted to show higher levels of % EF, with an almost statistically difference (p=0.0556), compared to the control group. The observed results showed the great potential of human SVF-based patches in the improvement of the heart pump function.

Vascular graft storage solution preserves endothelial function

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Karl Landsteiner Institute Cardiovascular Research

Background

Saline is still the most widely used storage and flushing solution in cardiovascular procedures despite knowing evidence of its influence on the human endothelial cell function. Aim of this study was to assess the effect of DuraGraft©, an intraoperative graft treatment solution, on human saphenous vein segments, rat aortic segments and human umbilical vein endothelial cells (HUVECs) in comparison to saline.

Methods

Within 12 patients undergoing aortocoronary bypass surgery, saphenous vein graft segments were randomized to DuraGraft© (n=12/6) or saline (n=12/6) solution before intraoperative storage. These segments as well as rat aortic segments underwent assessment of vascular function in a multichamber isometric myograph system in comparison to Krebs-Henseleit solution (KHS), a physiologic organ buffer solution. Additionally, human umbilical vein endothelial cells (HUVECs) were used for cell viability tests.

Results

KCl-induced contraction showed a tendency toward increase when treated with DuraGraft© compared to normal saline preservation of human vein segments (24.73±16.22 vs. 15.59±9.53 N/m2, P

Conclusion

DuraGraft© demonstrated a favorable effect on graft relaxation and contraction indicating preservation of vascular endothelial function. Saline is clearly not only inferior to this specialized solution but may show additional harmful effects to viability.

Tenascin-C provokes cardiac fibrosis and endothelial impairment in Duchenne Muscular Dystrophy

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): FWF Austrian Science Fund

Cardiac fibrosis and dilated cardiomyopathy are major contributors to mortality in Duchenne muscular dystrophy (DMD) patients. There is a growing collection of evidence that Tenascin C (TN-C) plays a maladaptive role in cardiac remodelling and fibrosis.

Our aims were to 1) assess the vascular dysfunction and cardiac fibrosis and its link to TN-C in a mouse model of DMD and 2) explore the effect of knocking out TN-C in dystrophic mice.

Male wt, mdx and mdx TN-C KO age-matched mice were used. Cardiac fibrosis was assessed on tissue sections. Wire myography was used to test the vascular reactivity and endothelial cells (ECs) were isolated from mouse lung tissues to characterize the oxidative stress and inflammatory marker expression. To study the signalling pathways contributing to cardiac fibrosis, human cardiac fibroblasts (hCFs) were treated with TN-C or TGF-β and gene expression and epigenetic regulation of p65 were assessed.

Cardiac fibrosis was markedly increased in mdx mice which was accompanied with elevated TN-C level in cardiac tissue and plasma compared to wt animals. In addition, endothelial cells isolated from mdx mice also showed a marked upregulation of oxidative stress and inflammatory markers and in line with that vascular endothelial function was impaired in mdx mice. Interestingly, mdx- TN-C KO mice showed preserved vascular function as well as reduced cardiac fibrosis compared to age-matched mdx mice. hCFs treated with TN-C or TGF-β showed increased collagen and α-SMA expressions which could be reduced by TN-C siRNA. In addition, both TN-C and TGF-β promote p65/NF-κB promoter demethylation and subsequently stimulate pro-inflammatory and pro-fibrotic signalling, which could be reversed by applying p38 MAPK inhibitor in hCFs.

TN-C promotes oxidative stress and inflammation in ECs and fibroblasts, contributing to severe endothelial dysfunction and cardiac fibrosis. In addition, activation of NF-κB p65 signalling pathway may play a role in TN-C induced fibrosis. Thus, TN-C may be a critical mediator and potential target for therapy in DMD.

Associations between use of expressed human milk at 2 weeks postpartum and human milk feeding practices to 6 months: a prospective cohort study with vulnerable women in Toronto, Canada

OBJECTIVES

To examine whether use of expressed human milk in the first two weeks postpartum is associated with cessation of human milk feeding and non-exclusive human milk feeding up to 6 months.

DESIGN

Pooled data from two prospective cohort studies SETTING: Three Canada Prenatal Nutrition Program (CPNP) sites serving vulnerable families in Toronto, Canada.

PARTICIPANTS

337 registered CPNP clients enrolled prenatally from 2017 to 2020; 315 (93%) were retained to 6 months postpartum.

EXCLUSIONS

pregnancy loss or participation in prior related study; Study B: preterm birth (<34 weeks); plan to move outside Toronto; not intending to feed human milk; hospitalisation of mother or baby at 2 weeks postpartum.

PRIMARY AND SECONDARY OUTCOME MEASURES

Main exposure variable: any use of expressed human milk at 2 weeks postpartum.

OUTCOMES

cessation of human milk feeding by 6 months; non-exclusive human milk feeding to 4 months and 6 months postpartum.

RESULTS

All participants initiated human milk feeding and 80% continued for 6 months. Exclusive human milk feeding was practiced postdischarge to 4 months by 28% and to 6 months by 16%. At 2 weeks postpartum, 34% reported use of expressed human milk. Any use of expressed human milk at 2 weeks was associated with cessation of human milk feeding before 6 months postpartum (aOR 2.66; 95% CI 1.41 to 5.05) and with non-exclusive human milk feeding to 4 months (aOR 2.19; 95% CI 1.16 to 4.14) and 6 months (aOR 3.65; 95% CI 1.50 to 8.84).

TRIAL REGISTRATION NUMBERS

NCT03400605, NCT03589963.

Differences in Suicide-Related Twitter Content According to User Influence

Background: The content of suicide-specific social media posts may impact suicide rates, and putatively harmful and/or protective content may vary by the author's influence. Aims: This study sought to characterize how suicide-related Twitter content differs according to user influence. Method: Suicide-related tweets from July 1, 2015, to June 1, 2016, geolocated to Toronto, Canada, were collected and randomly selected for coding (n = 2,250) across low, medium, or high user influence levels (based on the number of followers, tweets, retweets, and posting frequency). Logistic regression was used to identify differences by user influence for various content variables. Results: Low- and medium-influence users typically tweeted about personal experiences with suicide and associations with mental health and shared morbid humor/flippant tweets. High-influence users tended to tweet about suicide clusters, suicide in youth, older adults, indigenous people, suicide attempts, and specific methods. Tweets across influence levels predominantly focused on suicide deaths, and few described suicidal ideation or included helpful content. Limitations: Social media data were from a single location and epoch. Conclusion: This study demonstrated more problematic content vis-à-vis safe suicide messaging in tweets by high-influence users and a paucity of protective content across all users. These results highlight the need for further research and potential intervention.

Establishing a multicenter, preclinical consortium in resuscitation: A pilot experimental trial evaluating epinephrine in cardiac arrest

BACKGROUND

Large animal studies are an important step in the translation pathway, but single laboratory experiments do not replicate the variability in patient populations. Our objective was to demonstrate the feasibility of performing a multicenter, preclinical, randomized, double-blinded, placebo-controlled cardiac arrest trial. We evaluated the effect of epinephrine on coronary perfusion pressure (CPP) as previous single laboratory studies have reported mixed results.

METHODS

Forty-five swine from 5 different laboratories (Ann Arbor, MI; Baltimore, MD; Los Angeles, CA; Pittsburgh, PA; Toronto, ON) using a standard treatment protocol. Ventricular fibrillation was induced and left untreated for 6 min before starting continuous cardiopulmonary resuscitation (CPR). After 2 min of CPR, 9 animals from each lab were randomized to 1 of 3 interventions given over 12 minutes: (1) Continuous IV epinephrine infusion (0.00375 mg/kg/min) with placebo IV normal saline (NS) boluses every 4 min, (2) Continuous placebo IV NS infusion with IV epinephrine boluses (0.015 mg/kg) every 4 min or (3) Placebo IV NS for both infusion and boluses. The primary outcome was mean CPP during the 12 mins of drug therapy.

RESULTS

There were no significant differences in mean CPP between the three groups: 14.4 ± 6.8 mmHg (epinephrine Infusion), 16.9 ± 5.9 mmHg (epinephrine bolus), and 14.4 ± 5.5 mmHg (placebo) (p = NS). Sensitivity analysis demonstrated inter-laboratory variability in the magnitude of the treatment effect (p = 0.004).

CONCLUSION

This study demonstrated the feasibility of performing a multicenter, preclinical, randomized, double-blinded cardiac arrest trials. Standard dose epinephrine by bolus or continuous infusion did not increase coronary perfusion pressure during CPR when compared to placebo.