Factors Associated With Mortality and Hospice Use Among Medicare Beneficiaries With Heart Failure Who Received Home Health Services

BACKGROUND

Although many Medicare beneficiaries with heart failure (HF) are discharged with home health services, little is known about mortality rates and hospice use in this group.

OBJECTIVES

To identify risk factors for 6-month mortality and hospice use among patients hospitalized due to HF who receive home health care, which could inform efforts to improve palliative and hospice use for these patients.

METHODS

A retrospective cohort analysis was conducted in a 100% national sample of Medicare fee-for-service beneficiaries with HF who were discharged to home health care between 2017 and 2018. Multivariable Cox regression models examined factors associated with 6-month mortality, and multivariable logistic regression models examined factors associated with hospice use at the time of death.

RESULTS

A total of 285,359 Medicare beneficiaries were hospitalized with HF and discharged with home health care; 15.5% (44,174) died within 6 months. Variables most strongly associated with mortality included: age > 85 years (hazard ratio [HR] 1.66, 95% CI 1.61-1.71), urgent/emergency hospital admission (HR 1.68, 1.61-1.76), and "serious" condition compared to "stable" condition (HR 1.64, CI 1.52-1.78). Among 44,174 decedents, 48.2% (21,284) received hospice care at the time of death. Those with lower odds of hospice use at death included patients who were: < 65 years (odds ratio [OR] 0.65, CI 0.59-0.72); of Black (OR 0.64, CI 0.59-0.68) or Hispanic race/ethnicity (OR 0.79, CI 0.72-0.88); and Medicaid-eligible (OR 0.80, CI 0.76-0.85).

CONCLUSIONS

Although many patients hospitalized for HF are at risk of 6-month mortality and may benefit from palliative and/or hospice services, our findings indicate under-use of hospice care and important disparities in hospice use by race/ethnicity and socioeconomic status.

How Do Quantitative Tissue Imaging Outcomes in Acute Ischemic Stroke Relate to Clinical Outcomes?

BACKGROUND AND PURPOSE

Infarct volume and other imaging markers are increasingly used as surrogate measures for clinical outcome in acute ischemic stroke research, but how improvements in these imaging surrogates translate into better clinical outcomes is currently unclear. We investigated how changes in infarct volume at 24 hours alter the probability of achieving good clinical outcome (modified Rankin Scale [mRS] 0-2).

METHODS

Data are from endovascular thrombectomy patients from the randomized controlled ESCAPE-NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischaemic Stroke) trial. Infarct volume at 24 hours was manually segmented on non-contrast computed tomography or diffusion-weighted magnetic resonance imaging. Probabilities of achieving good outcome based on infarct volume were obtained from a multivariable logistic regression model. The probability of good outcome was plotted against infarct volume using linear spline regression.

RESULTS

A total of 1,099 patients were included in the analysis (median final infarct volume 24.9 mL [interquartile range: 6.6-92.2]). The relationship between total infarct volume and good outcome probability was nearly linear for infarct volumes between 0 mL and 250 mL. In this range, a 10% increase in the probability of achieving mRS 0-2 required a decrease in infarct volume of approximately 34.0 mL (95% confidence interval: -32.5 to -35.6). At infarct volumes above 250 mL, the probability of achieving mRS 0-2 probability was near zero. The relationships of tissue-specific infarct volumes and parenchymal hemorrhage volume generally showed similar patterns, although variability was high.

CONCLUSION

There seems to be a near-linear association between total infarct volume and probability of achieving good outcome for infarcts up to 250 mL, whereas patients with infarct volumes greater than 250 mL are highly unlikely to have a favorable outcome.

Experiences and resultant care gaps among women with HIV in Canada: concept mapping the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS) findings

OBJECTIVES

The community-based, longitudinal, Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS) explored the experiences of women with HIV in Canada over the past decade. CHIWOS' high-impact publications document significant gaps in the provision of healthcare to women with HIV. We used concept mapping to analyse and present a summary of CHIWOS findings on women's experiences navigating these gaps.

DESIGN

Concept mapping procedures were performed in two steps between June 2019 and March 2021. First, two reviewers (AY and PM) independently reviewed CHIWOS manuscripts and conference abstracts written before 1 August 2019 to identify main themes and generate individual concept maps. Next, the preliminary results were presented to national experts, including women with HIV, to consolidate findings into visuals summarising the experiences and care gaps of women with HIV in CHIWOS.

SETTING

British Columbia, Ontario and Quebec, Canada.

PARTICIPANTS

A total of 18 individual CHIWOS team members participated in this study including six lead investigators of CHIWOS and 12 community researchers.

RESULTS

Overall, a total of 60 peer-reviewed manuscripts and conference abstracts met the inclusion criteria. Using concept mapping, themes were generated and structured through online meetings. In total, six composite concept maps were co-developed: quality of life, HIV care, psychosocial and mental health, sexual health, reproductive health, and trans women's health. Two summary diagrams were created encompassing the concept map themes, one for all women and one specific to trans women with HIV. Through our analysis, resilience, social support, positive healthy actions and women-centred HIV care were highlighted as strengths leading to well-being for women with HIV.

CONCLUSIONS

Concept mapping resulted in a composite summary of 60 peer-reviewed CHIWOS publications. This activity allows for priority setting to optimise care and well-being for women with HIV.

Feasibility study of the multishot gradient-echo planar imaging sequence in non-enhanced and free-breathing whole-heart magnetic resonance coronary angiography

AIM

To investigate the feasibility of non-enhanced and free-breathing whole-heart magnetic resonance coronary angiography (MRCA) using multishot gradient-echo planar imaging (MSG-EPI).

MATERIALS AND METHODS

In total, 29 healthy volunteers were recruited for free-breathing whole-heart MRCA acquisition using the MSG-EPI sequence and fast gradient echo (GRE) sequence. After the examination, the actual scanning times, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the left main (LM) coronary artery, subjective quality scores for each segment, and evaluable length of the coronary artery were recorded and statistically analysed.

RESULTS

There was no significant difference between the SNRLM of the MSG-EPI sequence and fast GRE sequence (p=0.130), but the CNRLM of the MSG-EPI sequence was higher (p=0.001). The subjective quality score of the mid- and distal left anterior descending branch as well as the distal circumflex branch of the coronary artery in the MSG-EPI sequence was higher than that in the fast GRE sequence (p=0.003, 0.001, and 0.003, respectively). The evaluable length of the left anterior descending branch and the circumflex branch was better using the MSG-EPI sequence than that of the fast GRE sequence (p=0.015 and < 0.001, respectively). Moreover, the scanning time of the MSG-EPI sequence was 54.5% less than that of the fast GRE sequence (p<0.001).

CONCLUSION

The MSG-EPI sequence improves the subjective and objective image quality of MRCA as well as reduces the scanning time.

Inflammatory vaginitis in four B-cell suppressed women with Multiple Sclerosis

B-cell depleting therapies are effective in multiple sclerosis (MS) and are widely used (Hauser et al., 2017). Inflammatory vaginitis (IV), characterized by unexplained vaginal symptoms including mucopurulent discharge, pain, irritation, and dyspareunia, has been reported in one MS patient on ocrelizumab (Filikci and Jensen, 2022), and to be present in 3.5 % of women on rituximab for autoimmune diseases (Yockey et al., 2021). We report here four cases of IV in B cell depleted women with MS. B-cell reconstitution was temporally associated with improvement of IV symptoms. Further investigation and vigilance for this potential treatment emergent adverse event affecting sexual and reproductive health of women with MS is needed.

Canadian Stroke Best Practice Recommendations: Acute Stroke Management, 7th Edition Practice Guidelines Update, 2022

The 2022 update of the Canadian Stroke Best Practice Recommendations (CSBPR) for Acute Stroke Management, 7th edition, is a comprehensive summary of current evidence-based recommendations, appropriate for use by an interdisciplinary team of healthcare providers and system planners caring for persons with an acute stroke or transient ischemic attack. These recommendations are a timely opportunity to reassess current processes to ensure efficient access to acute stroke diagnostics, treatments, and management strategies, proven to reduce mortality and morbidity. The topics covered include prehospital care, emergency department care, intravenous thrombolysis and endovascular thrombectomy (EVT), prevention and management of inhospital complications, vascular risk factor reduction, early rehabilitation, and end-of-life care. These recommendations pertain primarily to an acute ischemic vascular event. Notable changes in the 7th edition include recommendations pertaining the use of tenecteplase, thrombolysis as a bridging therapy prior to mechanical thrombectomy, dual antiplatelet therapy for stroke prevention, the management of symptomatic intracerebral hemorrhage following thrombolysis, acute stroke imaging, care of patients undergoing EVT, medical assistance in dying, and virtual stroke care. An explicit effort was made to address sex and gender differences wherever possible. The theme of the 7th edition of the CSBPR is building connections to optimize individual outcomes, recognizing that many people who present with acute stroke often also have multiple comorbid conditions, are medically more complex, and require a coordinated interdisciplinary approach for optimal recovery. Additional materials to support timely implementation and quality monitoring of these recommendations are available at www.strokebestpractices.ca.

Long non-coding RNA generated from CDKN1A gene by alternative polyadenylation regulates p21 expression during DNA damage response

Alternative Polyadenylation (APA) is an emerging mechanism for dynamic changes in gene expression. Previously, we described widespread APA occurrence in introns during the DNA damage response (DDR). Here, we show that a DDR-activated APA event occurs in the first intron of CDKN1A, inducing an alternate last exon-containing lncRNA. We named this lncRNA SPUD (Selective Polyadenylation Upon DNA Damage). SPUD localizes to polysomes in the cytoplasm and is detectable as multiple isoforms in available high-throughput studies. SPUD has low abundance compared to the CDKN1A full-length isoform under non-stress conditions, and SPUD is induced in cancer and normal cells under a variety of DNA damaging conditions in part through p53. The RNA binding protein HuR binds to and promotes the stability of SPUD precursor RNA. SPUD induction increases p21 protein, but not mRNA levels, affecting p21 functions in cell-cycle, CDK2 expression and cell growth. Like CDKN1A full-length isoform, SPUD can bind two competitive p21 translational regulators, the inhibitor calreticulin and the activator CUGBP1; SPUD alters their association with CDKN1A full-length in a DDR-dependent manner, promoting CDKN1A translation. Together, these results show a new regulatory mechanism by which a lncRNA controls p21 expression post-transcriptionally, highlighting lncRNA relevance in DDR progression and cell-cycle.

Real-World Experience With Tofacitinib Dose De-Escalation in Patients With Moderate and Severe Ulcerative Colitis

BACKGROUND & AIMS

Tofacitinib is associated with sustained steroid-free remission in patients with ulcerative colitis (UC), with the lowest effective dose recommended for maintenance therapy. However, there are limited real-world data to guide decisions on the optimal maintenance regimen. We aimed to evaluate predictors and outcomes of disease activity after tofacitinib dose de-escalation in this population.

METHODS

Included were adults with moderate-severe UC treated with tofacitinib between June 2012 and January 2022. The primary outcome was evidence of UC disease activity-related events: hospitalization/surgery, corticosteroid initiation, tofacitinib dose increase, or therapy switch.

RESULTS

Among 162 patients, 52% continued 10 mg twice daily while 48% underwent dose de-escalation to 5 mg twice daily. Cumulative incidence rates of UC events at 12 months were similar in patients with and without dose de-escalation (56% vs 58%; P = .81). In univariable Cox regression among patients with dose de-escalation, an induction course with 10 mg twice daily for more than 16 weeks was protective of UC events (hazard ratio [HR], 0.37; 95% CI, 0.16-0.85) while ongoing severe disease (Mayo 3) was associated with UC events (HR, 6.41; 95% 95% CI, 2.23-18.44), which remained significant after adjusting for age, sex, duration of induction course, and corticosteroid use at dose de-escalation (HR, 6.05; 95% CI, 2.00-18.35). Twenty-nine percent of patients with UC events had their dose re-escalated to 10 mg twice daily, with only 63% able to recapture clinical response at 12 months.

CONCLUSIONS

In this real-world cohort, we observed a 56% cumulative incidence of UC events at 12 months in patients with tofacitinib dose de-escalation. Observed factors associated with UC events after dose de-escalation included induction course for fewer than 16 weeks and active endoscopic disease 6 months after initiation.

FLASH-RT does not affect chromosome translocations and junction structures beyond that of CONV-RT dose-rates

BACKGROUND AND PURPOSE

The impact of radiotherapy (RT) at ultra high vs conventional dose rate (FLASH vs CONV) on the generation and repair of DNA double strand breaks (DSBs) is an important question that remains to be investigated. Here, we tested the hypothesis as to whether FLASH-RT generates decreased chromosomal translocations compared to CONV-RT.

MATERIALS AND METHODS

We used two FLASH validated electron beams and high-throughput rejoin and genome-wide translocation sequencing (HTGTS-JoinT-seq), employing S. aureus and S. pyogenes Cas9 "bait" DNA double strand breaks (DSBs) in HEK239T cells, to measure differences in bait-proximal repair and their genome-wide translocations to "prey" DSBs generated after various irradiation doses, dose rates and oxygen tensions (normoxic, 21% O2; physiological, 4% O2; hypoxic, 2% and 0.5% O2). Electron irradiation was delivered using a FLASH capable Varian Trilogy and the eRT6/Oriatron at CONV (0.08-0.13 Gy/s) and FLASH (1x102-5x106 Gy/s) dose rates. Related experiments using clonogenic survival and γH2AX foci in the 293T and the U87 glioblastoma lines were also performed to discern FLASH-RT vs CONV-RT DSB effects.

RESULTS

Normoxic and physioxic irradiation of HEK293T cells increased translocations at the cost of decreasing bait-proximal repair but were indistinguishable between CONV-RT and FLASH-RT. Although no apparent increase in chromosome translocations was observed with hypoxia-induced apoptosis, the combined decrease in oxygen tension with IR dose-rate modulation did not reveal significant differences in the level of translocations nor in their junction structures. Furthermore, RT dose rate modality on U87 cells did not change γH2AX foci numbers at 1- and 24-hours post-irradiation nor did this affect 293T clonogenic survival.

CONCLUSION

Irrespective of oxygen tension, FLASH-RT produces translocations and junction structures at levels and proportions that are indistinguishable from CONV-RT.

Rib Fragility Fractures and Chest Wall Hematoma After Cardiopulmonary Resuscitation Training: A Case Report

Fragility fractures commonly manifest as complications in individuals with diminished bone mineral density and other risk factors. The hip, vertebral body, and wrist are the most documented locations of fragility fractures among patients with osteoporosis or osteopenia. This report presents a rare case of multiple fragility fractures of the right ribs accompanied by an adjacent right chest wall hematoma in an otherwise healthy 60-year-old woman after participating in cardiopulmonary resuscitation (CPR) training. Upon further workup, a diagnosis of osteopenia was established. This report aims to underscore a potential complication in those performing CPR and outline the clinicoradiological presentations, diagnostic workup, and treatment of fragility fractures in patients with no history of prior underlying skeletal conditions or malignancy.

An Analysis of Patients Treated with Stereotactic Body Radiotherapy for Metastatic Urinary Tract Tumors to Identify Predictors of Response

PURPOSE/OBJECTIVE(S)

To identify selection criteria linked to outcomes in patients treated with stereotactic body radiotherapy (SBRT) for metastatic tumors of the urinary tract (UT).

MATERIALS/METHODS

Single institution retrospective analysis of SBRT treated patients for oligometastatic/progressive UT tumors from 2006-2022. Charts were queried for M1 status at diagnosis or during disease course, treatment details (surgery, SBRT, systemic therapy), metabolic status (diabetes [DM], BMI) and outcomes. A linear quadratic formula was used to calculate the biologically effective dose (BED) using an α/β of 10 for tumor. Descriptive statistics portrayed the cohort, and analyses were done at patient and site level. Time-to-event analyses, including overall survival (OS) and progression-free survival (PFS) from SBRT, were assessed by the Kaplan-Meier method. Cox regression was used for univariable (UVA) and multivariable analyses (MVA) to identify predictors of outcomes.

RESULTS

A total of 35 patients were treated at 44 metastatic sites, including: bone (25%), node (36.4%), lung (20.5%), soft tissue (13.6%) and liver (4.5%). Most were male (74.3%) with a median age of 70 (range: 51-89), without DM (60%) having a median BMI of 29.8, and ECOG <2 (97.1%) at time of SBRT. Six (17.1%) patients were M1 at diagnosis. Of the 29 non-M1 patients, 86.2% received definitive local therapy (LT), 58.6% had at least T3/N+ disease, 75.8% received systemic therapy with a median of 2 agents (range: 1-6) prior to SBRT. Sixteen (45.7%) received immunotherapy (IO) with most receiving this before (75%) and after (56.2%) SBRT. Six patients had positive PD-L1 status (n = 10). The median RT dose, fractionation and BED was 40 Gy (range: 14-46), 5 fractions, and 72 (range: 28-132), respectively. At a median follow-up of 34.8, the median OS was 18.4 m (range: 9.3-27.4) with a 2-year OS of 35.9%. At patient level, 62.8% recurred after SBRT. The median PFS after SBRT was 5.3 m (range: 1.8-8.7) with a 2-yr PFS of 29.3%. Patient-level PFS was improved with LT (6.7 vs 1.4 m; p = 0.001) and DM (NR vs 2.9 m; p = 0.015), whereas improved OS was related with LT (18.9 vs 6.6 m; p = 0.03), DM (p = 0.04), ECOG (p = 0.004), and no relapse after SBRT (NR vs 9.8 m; p <0.001). Exposure to < 3 systemic agents prior to SBRT portended better PFS (6.7 vs 2.6 m; p = 0.04) without any impact by IO. At site level, 20.4% of sites had local relapse with 4 being the first event. Site was related with PFS (p = 0.009) with order of increased relapse risk being liver > bone > soft tissue > node > lung. No dosimetric feature was related with recurrence risk. On MVA, both DM (p = 0.02) and LT (p = 0.002) were predictive for PFS. Only recurrence after SBRT predicted for OS on MVA (HR: 6.7, 95% CI: 1.4-31; p = 0.014). In the IO subset, median PFS was 5.3 m and OS was 9.4 m, with no difference seen with IO-SBRT sequence or PDL1 status.

CONCLUSION

Optimized selection criteria for metastasis-directed therapy in patients with UT tumors is unclear, notably with IO. Future studies may benefit by assessing circulating tumor markers prior to SBRT.

High-Dose Rate Brachytherapy Alone for Treatment of Unfavorable Intermediate Risk Prostate Cancer: A Propensity-Score Matched Analysis

PURPOSE/OBJECTIVE(S)

To demonstrate the feasibility of high-dose rate brachytherapy (HDR BT) as monotherapy for unfavorable intermediate risk (UIR) prostate cancer by comparing survival outcomes of HDR BT alone against external beam radiation therapy (EBRT) + HDR BT boost, +/- androgen deprivation therapy (ADT) using propensity-score matched (PSM) data.

MATERIALS/METHODS

This retrospective study queried two data registries collecting patient data from 1991 to present. 633 patients with UIR prostate cancer treated with HDR BT alone, HDR BT+EBRT or HDR+EBRT+ADT were included. HDR BT patients received 42-45Gy/6 fractions (fx) or 27 Gy/2 fx. For HDR BT+EBRT, the HDR dose was 20-24 Gy/2 fx, 24 Gy/4 fx, or 15 Gy/1 fx. EBRT patients received 45 Gy/25 fx to the prostate +/- pelvic nodes. GU/GI toxicities were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Time-to-event analyses were carried out to evaluate the relationship between treatments and five primary endpoints of interest: freedom from biochemical recurrence (FFBC), freedom from distant metastasis (FFDM), freedom from local failure (FFLF), cancer specific survival (CSS), and overall survival (OS) at 5 years. PSM was performed with one-to-n matching. Logistic regression was used to estimate the respective propensity scores. The five potential confounders identified were T-stage, Gleason score, pre-treatment PSA, age, and percent positive cores. Balance was checked using the standardized mean difference of covariates. Univariate and multivariate analyses were conducted on the matched data. Toxicity analysis was performed via association between a change in pre- and post-treatment GU/GI toxicity status and the treatment group, as well as incidence of post-treatment severe GI/GU toxicity (grade 3 or higher) and the treatment group.

RESULTS

Univariate analysis with Kaplan-Meier method and log rank test comparison between the three cohorts demonstrated no significant difference in all survival outcomes FFBC, FFDM, FFLF, CSS, OS (p = 0.15, 0.19, 0.29, 0.57, 0.28, respectively). Multivariate analysis with Cox proportional hazard regression showed no differences in HR for FFBC and OS (p = 0.95, 0.11) with addition of EBRT, or with EBRT+ADT (p = 0.17, 0.24); no fit was obtainable for FFDM, CSS, FFLF. Toxicities between the three cohorts were not significantly different when comparing post-treatment and baseline GI/GU symptoms (p = 0.53/1). No Grade 2 or 3 GI toxicities were identified, while 8%/1% HDR patients, 10%/1% HDR+EBRT patients, and 12%/2% HDR+EBRT+ADT patients experienced Grade 2/3 GU toxicities. The incidence of grade 3 or higher GU toxicities between the three groups was not significantly different (p = 0.91).

CONCLUSION

This propensity-score matched study demonstrates the feasibility of HDR BT alone for effective treatment of UIR prostate cancer when compared to HDR+EBRT or HDR+EBRT+ADT, while potentially minimizing the added toxicities of EBRT and the undesirable side effect profile of ADT.

FLASH-RT does not affect chromosome translocations and junction structures beyond that of CONV-RT dose-rates

The molecular and cellular mechanisms driving the enhanced therapeutic ratio of ultra-high dose-rate radiotherapy (FLASH-RT) over slower conventional (CONV-RT) radiotherapy dose-rate remain to be elucidated. However, attenuated DNA damage and transient oxygen depletion are among several proposed models. Here, we tested whether FLASH-RT under physioxic (4% O 2 ) and hypoxic conditions (≤2% O 2 ) reduces genome-wide translocations relative to CONV-RT and whether any differences identified revert under normoxic (21% O 2 ) conditions. We employed high-throughput rejoin and genome-wide translocation sequencing ( HTGTS-JoinT-seq ), using S. aureus and S. pyogenes Cas9 "bait" DNA double strand breaks (DSBs), to measure differences in bait-proximal repair and their genome-wide translocations to "prey" DSBs generated by electron beam CONV-RT (0.08-0.13Gy/s) and FLASH-RT (1×10 2 -5×10 6 Gy/s), under varying ionizing radiation (IR) doses and oxygen tensions. Normoxic and physioxic irradiation of HEK293T cells increased translocations at the cost of decreasing bait-proximal repair but were indistinguishable between CONV-RT and FLASH-RT. Although no apparent increase in chromosome translocations was observed with hypoxia-induced apoptosis, the combined decrease in oxygen tension with IR dose-rate modulation did not reveal significant differences in the level of translocations nor in their junction structures. Thus, Irrespective of oxygen tension, FLASH-RT produces translocations and junction structures at levels and proportions that are indistinguishable from CONV-RT.

Abstract P1-10-02: FLASH-RT, ultra-high dose rate rate radiotherapy, is as effective as conventional dose rate radiotherapy in eradicating tumor in a preclinical model of breast cancer

Problem Statement: Radiation therapy (RT) for breast cancer (BC) can induce skin and soft tissue fibrosis, raises concerns over cardiac and pulmonary injury, is associated with higher rates of lymphedema and shoulder dysfunction with regional nodal irradiation, and significantly increases complication rates in women undergoing implant-based reconstruction due to radiation toxicity. Although these toxicities are not generally associated with higher mortality, in general, they can represent significant setbacks with respect to quality of life. These toxicities dissuade some patients from breast conservation leading to unnecessary mastectomy and can lead patients to omit reconstruction after mastectomy or choose more extensive autologous breast reconstruction. Women with implant-based reconstruction and radiotherapy have known higher rates of reconstruction failure. Purpose: Ultra-high dose rate radiation (FLASH) has been shown to induce less normal tissue toxicity, therefore if tumor control of FLASH-RT would be comparable to conventional radiotherapy (CONV) then it has the potential to lower morbidity associated with radiotherapy for breast cancer and allow overall improved outcomes. At first, we aimed to determine the effectiveness of FLASH-RT compared to CONV in eradicating small breast tumors in an orthotopic BC model using single-fraction 20 or 30Gy RT to compare effectiveness of FLASH-RT vs CONV. Methods: Radiation sensitive, syngeneic mammary tumor cell line Py117, that efficiently forms non-metastatic orthotopic tumors in C57BL/6 mice, were injected (106 cells) into the left 4th mammary fat pad. 30mm3 tumors or a range of greater volumes (200-800mm3) were irradiated with single-fraction 20 or 30Gy with a 2x2cm radiation field (~17MeV beams), exposing only 5mm of the surrounding tissue. FLASH RT was delivered with 2Gy per pulse at dose rate ~200Gy/s compared to CONV dose rate of 0.13Gy/s Results: Single-fraction 20Gy suppressed 30mm3 tumor growth until ~day 15 post-RT then regrew for both FLASH and CONV, while 30mm3 tumors were eradicated with both FLASH and CONV at 30Gy. Larger tumors irradiated with 30Gy regressed until ~day 12 post-RT then regrew for both FLASH and CONV. There was no significant difference in growth suppression or tumor eradication between FLASH and CONV in any cohort. Conclusion: In this murine model of breast cancer, FLASH is as effective as CONV in controlling tumor growth. Future studies will extend the evaluation of the tumor control using clinically relevant fractionated dose schedules to be followed by comparisons of tumor control in xenograft models. Additional studies will assess normal tissue toxicity of FLASH vs CONV in murine models of implant-based breast reconstruction. We have established collaborations to understand differences in molecular pathways activated by FLASH vs CONV in tumor and normal tissue to explain the observed experimental differences in normal tissue, tumor, and cancer stem cells.

Citation Format: Frederick Dirbas, Stavros Melemenidis, Bill Loo, Kathleen Horst, Edward E. Graves, Suparna Dutt, Vignesh Viswanathan, Brianna Lau, Amy Yu. FLASH-RT, ultra-high dose rate rate radiotherapy, is as effective as conventional dose rate radiotherapy in eradicating tumor in a preclinical model of breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-10-02.

A controlled forearm washing ex vivo method for assessing the impact of personal cleansing products on skin's acid mantle properties and antimicrobial defense against transient bacteria

BACKGROUND

An important trend in the personal care industry involves the development of advanced personal cleaning products that not only provide skin mildness but support skin's acid mantle properties and skin's natural antimicrobial defense function.

OBJECTIVE

The objective of this study was to develop a controlled forearm washing ex vivo method for assessing the impact of personal cleansing products on skin's acid mantle properties and antimicrobial defense against transient bacteria.

METHODS

We developed a controlled forearm washing ex vivo method (ex vivo NET method) to compare the impact of two representative personal cleansing products on skin's acid mantle properties and antimicrobial defense against transient bacteria: one was a low pH skin cleanser, and the other was a high pH soap cleanser. Skin pH was measured at baseline and four hours after the product application. Concurrently, D-squame tape stripping procedure was followed to sample the stratum corneum surface layers. Then, two selected transient bacteria: S.aureus and E.coli, were inoculated onto the D-Squame tapes and incubated under controlled conditions, respectively. The residual bacteria counts can provide an objective measure of skin's acid mantle properties against transient bacteria. Results from the ex vivo NET method were compared with the traditional in vivo cup-scrub RET method.

RESULTS

The skin pH was significantly lower four hours after washing the forearm with the low pH cleanser vs. the high pH soap, consistent with literatures. Interestingly, the skin surface washed by the low pH cleanser showed significantly higher hostility against representative transient bacteria as demonstrated by the lower counts of S. aureus by 1.09log and E. coli by 0.6log vs. the high pH soap based on the ex vivo NET method. Results from the ex vivo NET method was further supported by the traditional in vivo RET method which also showed the skin washed by the low pH cleanser had significantly lower counts of S. aureus and E. coli vs. the high pH soap.

CONCLUSIONS

The skin's acid mantle properties and antimicrobial defense can be directly impacted by the personal cleansing products. The low pH skin cleanser works better than the high pH soap for supporting skin's acid mantle properties and antimicrobial defense against transient bacteria. Results from the ex vivo NET method are consistent with the in vivo RET method. It is important that the ex vivo NET method offers many advantages since it is quicker to run with higher throughput and has better safety without the constraint of inoculating harmful microorganisms onto the human subjects.

Effect of testosterone therapy on migraine frequency and disability in two transgender patients: a case report

With an increasing number of patients seeking gender-affirming hormone therapy (GAHT), the clinical impact of testosterone treatments on headache needs to be determined. Our case report looks at the potential effect of testosterone on migraine among transgender patients. We present two transmasculine patients who used masculinising hormone therapy with testosterone. Both patients described their headache as moderate-to-severe pain with features that fulfilled the criteria for chronic migraine without aura. Following GAHT, one patient improved in both frequency and intensity of headache symptoms while the other noted improvement in headache intensity alone. Our report postulates that testosterone therapy may have a positive impact on headaches in individuals participating in GAHT, highlighting the need for further research on the role of testosterone therapy on headache in transmasculine individuals.

Long Non-Coding RNA Generated from CDKN1A Gene by Alternative Polyadenylation Regulates p21 Expression during DNA Damage Response

Alternative Polyadenylation (APA) is an emerging mechanism for dynamic changes in gene expression. Previously, we described widespread APA occurrence in introns during the DNA damage response (DDR). Here, we show that a DNA damage activated APA event occurs in the first intron of CDKN1A , inducing an alternate last exon (ALE)-containing lncRNA. We named this lncRNA SPUD (Selective Polyadenylation Upon Damage). SPUD localizes to polysomes in the cytoplasm and is detectable as multiple isoforms in available high throughput studies. SPUD has low abundance compared to the CDKN1A full-length isoform and is induced in cancer and normal cells under a variety of DNA damaging conditions in part through p53 transcriptional activation. RNA binding protein (RBP) HuR and the transcriptional repressor CTCF regulate SPUD levels. SPUD induction increases p21 protein, but not CDKN1A full-length levels, affecting p21 functions in cell-cycle, CDK2 expression, and cell viability. Like CDKN1A full-length isoform, SPUD can bind two competitive p21 translational regulators, the inhibitor calreticulin and the activator CUGBP1; SPUD can change their association with CDKN1A full-length in a DDR-dependent manner. Together, these results show a new regulatory mechanism by which a lncRNA controls p21 expression post-transcriptionally, highlighting lncRNA relevance in DDR progression and cellcycle.

1649. Ceftolozane-Tazobactam or Ceftazidime-Avibactam Versus Best Available Therapy in the Treatment of Difficult-to-Treat Pseudomonas aeruginosa Infections: a Retrospective Comparative Effectiveness Analysis of 195 U.S. Hospitals, 2016–2020

Background

Infections due to Pseudomonas aeruginosa displaying difficult-to-treat resistance (DTR-PA) necessitate the use of sub-efficacious and/or toxic “reserve” antibiotics and are associated with considerable morbidity and mortality. Ceftazidime-avibactam (CAZ-AVY) and ceftolozane-tazobactam (CEF-TAZO) are novel ß-lactam/ß-lactamase inhibitors (BLBLI) that tend to retain in vitro activity against DTR-PA. However, little is known about their in vivo effectiveness compared to reserve agents.

Methods

Inpatients aged ≥ 18 years with ≥1 blood, urine, respiratory, or body fluid culture growing DTR-PA who received targeted therapy with either CAZ-AVY, CEF-TAZO, or Best-Available Therapy (BAT) were identified in the Premier Healthcare Database. Primary outcome was in-hospital mortality or discharge to hospice and secondary outcome was length of hospital stay (LOS) for survivors. The primary outcome was compared for CAZ-AVY vs CEF-TAZO and novel agents (CAZ-AVY or CEF-TAZO) vs BAT using overlap weighting and binomial regression with downstream adjustment controlling for patient and treatment characteristics. The secondary outcomes were compared using overlap weighting and poisson regression with downstream adjustment controlling for patient and treatment characteristics.

Results

Between 2016 and 2020, 1,552 patients with DTR-PA infections were identified at 105 hospitals, of which 202 (13.0%) were treated with CAZ-AVY, 906 (58.4%) with CEF-TAZO, and 444 (28.6%) with BAT. Patient characteristics were similar among treatment groups (Table 1, Table 2). Overall crude mortality was 15.5%. The adjusted risk of mortality was lower in patients treated with CAZ-AVI (12.5%, 95% CI 7.9–17.1) vs CEF-TAZO (18.8%, 95% CI 15.9–21.8) for a risk difference of 6.3% (95% 1.1–11.5, p = 0.02). The novel agents were not associated with a reduced mortality risk when collectively compared to BAT (risk difference -1.1%, 95% CI -5.4; 3.2%). LOS favoured novel agents and were comparable for CAZ-AVY and CEF-TAZO.

Conclusion

In this real-world observational study of patients with DTR-PA infections, the novel ß-lactam/ß-lactamase inhibitors were comparably effective against BAT, though the use of CAZ-AVY was associated with a reduced mortality compared to CEF-TAZO.

Disclosures

All Authors: No reported disclosures.

Targeting acid ceramidase ameliorates fibrosis in mouse models of non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is a common cause of liver disease worldwide, and is characterized by the accumulation of fat in the liver. Non-alcoholic steatohepatitis (NASH), an advanced form of NAFLD, is a leading cause of liver transplantation. Fibrosis is the histologic feature most associated with liver-related morbidity and mortality in patients with NASH, and treatment options remain limited. In previous studies, we discovered that acid ceramidase (aCDase) is a potent antifibrotic target using human hepatic stellate cells (HSCs) and models of hepatic fibrogenesis. Using two dietary mouse models, we demonstrate that depletion of aCDase in HSC reduces fibrosis without worsening metabolic features of NASH, including steatosis, inflammation, and insulin resistance. Consistently, pharmacologic inhibition of aCDase ameliorates fibrosis but does not alter metabolic parameters. The findings suggest that targeting aCDase is a viable therapeutic option to reduce fibrosis in patients with NASH.

The petrosal artery and its variations: a comprehensive review and anatomical study with application to skull base surgery and neurointerventional procedures

BACKGROUND

The petrosal artery supplies several structures at the skull base and is often the focus of various neurointerventional procedures. Therefore, knowledge of its anatomy and variations is important to surgeons and interventionalists.

MATERIALS AND METHODS

Twenty latex injected cadaveric heads (40 sides) underwent microsurgical dissection of the petrosal artery. Documentation of the course of the artery and its branches were made. Measurements of the petrosal artery's length and diameter were performed using microcallipers.

RESULTS

A petrosal artery was identified on all sides. The mean length and diameter of the artery within the middle cranial fossa was 2.4 cm and 0.38 mm, respectively. Branches included the following: dural, ganglionic, V3 branches, branches extending through the foramen ovale, branches directly to the greater petrosal and lesser petrosal nerves, branches to the floor of the hiatus of the greater and lesser petrosal nerves, branch to the arcuate eminence, and superior tympanic artery. No statistically significant differences were noted between male and female specimens, but right-sided petrosal arteries were in general, larger in diameter than left sides.

CONCLUSIONS

A thorough anatomical knowledge of the petrosal artery and to its relationship to the facial nerve and other neurovascular structures is necessary to facilitate effective endovascular treatment and to preclude facial nerve complications.

"Our Hands Are Tied Until Your Doctor Gets Here": Nursing Perspectives on Inter-hospital Transfers

BACKGROUND

The transfer of patients between hospitals (inter-hospital transfer, or IHT) is a common occurrence for patients, but guidelines to ensure safe and effective IHTs are lacking. Poor IHTs result in higher rates of mortality, longer lengths of stay, and higher hospitalization costs compared to admissions from the emergency department. Nurses are often the first point of contact for IHT patients and can provide valuable insights on key challenges to IHT processes.

OBJECTIVE

To characterize the experiences of inpatient floor-level bedside nurses caring for IHT patients and identify care coordination challenges and solutions.

DESIGN/PARTICIPANTS/APPROACH

Qualitative study using semi-structured focus groups and interviews conducted from October 2019 to July 2020 with 21 inpatient floor-level nurses caring for adult medicine patients at an academic hospital. Nurses were recruited using a purposive convenience sampling approach. A combined inductive and deductive coding approach guided by thematic analysis was used for data analysis.

KEY RESULTS

Results from this study are mapped to the Agency for Healthcare Research and Quality Care Coordination Measurement Framework domains of communication, assessing needs and goals, and negotiating accountability. The following key themes characterize nurses' experiences with IHT related to these domains: (1) challenges with information exchange and team communication during IHT, (2) environmental and information preparation needed to anticipate transfers, and (3) determining responsibility and care plans after the IHT patient has arrived at the accepting facility.

CONCLUSIONS

Nurses described the absence of standardized processes to coordinate care before or at the time of patient arrival. Challenges to communication and coordination during IHTs negatively impacted patient care and nursing professional satisfaction. To streamline care for IHT patients and reduce nursing stress, future IHT interventions should include standardized handoff reports, timely identification and easy access to admitting clinicians, and timely clinician evaluation and orders.

Quantifying Contact Patterns: Development and Characteristics of the British Columbia COVID-19 Population Mixing Patterns Survey

Purpose

Several non-pharmaceutical interventions such as physical distancing, self-isolation, a stay-at-home order, hand washing, and schools and businesses closures were implemented in British Columbia (BC) following the first lab-tested case of COVID-19 on January 26, 2020. These interventions were aimed at minimizing in-person contacts that could potentially lead to new COVID-19 infections. The BC COVID-19 Population Mixing Patterns survey (BC-Mix) was established as a surveillance system to measure behaviour and contact patterns in BC over time to inform the timing of the easing/re-imposition of control measures. We describe the BC-Mix survey design and the demographic characteristics of respondents.

Methods & Materials

The ongoing repeated online survey was launched in September 2020. Participants are recruited through a variety of social media platforms including Instagram, Facebook, YouTube, and community group mailing lists. A follow up survey is sent to participants two to four weeks after completing the first iteration. Survey responses are weighted to BC's population by age, sex, geography, and ethnicity to obtain generalizable estimates. A survey completion rate of at least 33% AND a valid response for the sex questionnaire item AND a valid response for age questionnaire item were required for inclusion in weighting and further analysis. Additional indices such as material and social deprivation index, and residential instability are generated using census and location data.

Results

As of June 14, 2021, over 58,000 residents of BC had participated in the survey of which 31,007 survey responses were eligible for analysis. Of the eligible participants, about 60% provided consent for monthly follow up and about 26% provided their personal health numbers for linkage with other healthcare utilization databases. Approximately 51% were females 39% were 55 years or older, 63% identified as white or not a visible minority and 48% had at least a university degree.

Conclusion

The pandemic response is best informed by surveillance systems capable of timely assessment of behaviour patterns. BC-Mix survey respondents represented a large cohort of British Columbians providing near real-time information on behavioural and contact patterns in BC. Data from the BC-Mix survey continues to inform provincial COVID-19-related control measures.