Perception of unfamiliar caregivers during sickness - Using the new caregiver perception task (CgPT) during experimental endotoxemia

Social withdrawal is a well-established part of sickness behavior, but in some contexts sick animals might gain from keeping close instead of keeping away. For instance, sick individuals are more willing to be near known individuals who can provide care and safety (close others) compared to when healthy. Yet, interactions with some strangers might also be beneficial (i.e., healthcare professionals), but it is not known how sickness interplay with social behavior towards such individuals. Here, we assessed if sickness affects perception of caregivers and developed a new task, the Caregiver Perception Task (CgPT). Twenty-six participants conducted the CgPT, once after an injection of lipopolysaccharide (LPS, 0.8 ng/kg body weight, n = 24), and once after an injection of saline (n = 25), one hour and forty-five minutes post-injection. During the task, participants watched short videeo-clips of three types of caregivers: a healthcare professional taking care of a sick individual (HP-c), a healthcare professional not taking care of a sick individual (HP-nc), and a non-healthcare professional taking care of their sick adult child or partner (NHP-c). After each videeo clip, the likability, trustworthiness, professionalism, and willingness to interact with and receive care from the caregiver were rated on visual analogue scales. Results showed that participants injected with saline rated healthcare professionals who did not take care of a sick individual less positively on all aspects compared to healthcare professionals who took care of a sick individual. Moreover, compared to saline, LPS increased the participants' willingness to receive care from healthcare professionals and non-healthcare professionals providing care, but not from healthcare professionals not providing care. Thus, our results indicate that sick individuals may approach unknown individuals with potential to provide care and support.

Cryopreservation of cerebrospinal fluid cells preserves the transcriptional landscape for single-cell analysis

Cerebrospinal fluid (CSF) matrix biomarkers have become increasingly valuable surrogate markers of neuropsychiatric diseases in research and clinical practice. In contrast, CSF cells have been rarely investigated due to their relative scarcity and fragility, and lack of common collection and cryopreservation protocols, with limited exceptions for neurooncology and primary immune-based diseases like multiple sclerosis. the advent of a microfluidics-based multi-omics approach to studying individual cells has allowed for the study of cellular phenotyping, intracellular dynamics, and intercellular relationships that provide multidimensionality unable to be obtained through acellular fluid-phase analyses. challenges to cell-based research include site-to-site differences in handling, storage, and thawing methods, which can lead to inaccuracy and inter-assay variability. In the present study, we performed single-cell RNA sequencing (10x Genomics) on fresh or previously cryopreserved human CSF samples from three alternative cryopreservation methods: Fetal Bovine Serum with Dimethyl sulfoxide (FBS/DMSO), FBS/DMSO after a DNase step (a step often included in epigenetic studies), and cryopreservation using commercially available Recovery© media. In comparing relative differences between fresh and cryopreserved samples, we found little effect of the cryopreservation method on being able to resolve donor-linked cell type proportions, markers of cellular stress, and overall gene expression at the single-cell level, whereas donor-specific differences were readily discernable. We further demonstrate the compatibility of fresh and cryopreserved CSF immune cell sequencing using biologically relevant sexually dimorphic gene expression differences by donor. Our findings support the utility and interchangeability of FBS/DMSO and Recovery cryopreservation with fresh sample analysis, providing a methodological grounding that will enable researchers to further expand our understanding of the CSF immune cell contributions to neurological and psychiatric disease.

Considerations for study design in the DAHANCA 35 trial of protons versus photons for head and neck cancer

Proton radiotherapy offers a dosimetric advantage compared to photon therapy in sparing normal tissue, but the clinical evidence for toxicity reductions in the treatment of head and neck cancer is limited. The Danish Head and Neck Cancer Group (DAHANCA) has initiated the DAHANCA 35 randomised trial to clarify the value of proton therapy (NCT04607694). The DAHANCA 35 trial is performed in an enriched population of patients selected by an anticipated benefit of proton therapy to reduce the risk of late dysphagia or xerostomia based on normal tissue complication probability (NTCP) modelling. We present our considerations on the trial design and a test of the selection procedure conducted before initiating the randomised study.

Unshielded portable optically pumped magnetometer for the remote detection of conductive objects using eddy current measurements

Electrically conductive objects can be detected using the principle of electromagnetic induction, where a primary oscillating magnetic field induces eddy currents in the object, which in turn produce a secondary magnetic field that can be measured with a magnetometer. We have developed a portable radio-frequency optically pumped magnetometer (RF OPM) working in unshielded conditions with sub-pT/Hz magnetic field sensitivity when used for the detection of small oscillating magnetic fields, setting a new benchmark for the sensitivity of a portable RF OPM in unshielded conditions. Using this OPM, we have detected the induced magnetic field from aluminum disks with diameters as small as 1.5 cm and with the disks being ∼25 cm from both the excitation coil and the magnetometer. When used for eddy current detection, our magnetometer achieves a sensitivity of a 2-6 pT/Hz. We have also detected a moving aluminum disk using our RF OPM and analyzed the magnetometer signals, which depend on the position of the disk, illustrating the potential of high sensitivity RF OPMs for remote sensing applications.

Dose and robustness comparison of nominal, daily and accumulated doses for photon and proton treatment of sinonasal cancer

INTRODUCTION

The aim was to evaluate and compare the dosimetric effect and robustness towards day-to-day anatomical and setup variations in the delivered dose for photon and proton treatments of sinonasal cancer (SNC) patients.

MATERIALS AND METHODS

Photon (VMAT) and proton (IMPT) plans were optimized retrospectively for 24 SNC patients. Synthetic CTs (synCT) were obtained by deforming the planning CT (pCT) to the anatomy of every daily cone-beam CT. Both VMAT and IMPT plans were recalculated on the synCTs. The recalculated daily dose was accumulated over the whole treatment on the pCT. Target coverage and dose to organs and risk (OARs) were evaluated for all patients for the nominal, daily and accumulated dose distribution.

RESULTS

In general, dose to OARs farther away from the target, including brain, chiasm and contralateral optic nerve, was lower for proton plans than photon plans. Whereas, OARs in proximity of the target received a lower dose for photon plans. For proton plans, the target coverage (volume of CTV receiving 95% of prescribed dose), V95%, fell below 99% for 9/24 patients in one or more fractions. For photon plans, 4/24 patients had one or more fractions where V95% fell below 99%. For accumulated doses, V95% was below 99% only in two cases, but above 98% for all patients.

CONCLUSION

Photon and proton treatment have different strengths regarding OAR sparing. The robustness was high for both treatment modalities. Patient selection for either proton or photon radiation therapy of SNC patients should be based on a case-by-case comparison.

Hybrid high-intensity interval training using functional electrical stimulation leg cycling and arm ski ergometer for people with spinal cord injuries: a feasibility study

Aim

The aim was to assess safety and feasibility of Hybrid High-Intensity Interval Training (HIIT) using Functional Electrical Stimulation (FES) leg cycling and arm ski ergometer in people with Spinal Cord Injuries (SCI).

Method

Eight outpatients (mean age 42.8 years; 7 men) with stable SCI paraplegia (mean 14.5 years since injury) participated in hybrid HIIT (90% peak watts; 4 × 4–min intervals), three times a week (over 8 weeks). Primary outcomes were Adverse Events (AE), participant acceptability, shoulder pain, training intensity (% peak watts), and attendance.

Secondary outcomes were effect on peak oxygen uptake (VO₂peak) during FES hybrid poling, mean watts, self-reported leisure time physical activity, quality of life, and fatigue.

Results

No serious AE occurred; acceptability with the training modality was high, while shoulder pain increased by 9% (SD 95.2). During training, 50% of the participants reached > 90% peak watts during the intervals, three with the legs (FES cycle) and one with the arms (Ski-Erg). Overall, mean training intensity (% peak watts) was 92% (SD 18.9) for legs and 82% (SD 10.3) for arms. Proportion of fulfilled training minutes was 82% (range 36–100%); one participant dropped out after 6 weeks due to back pain. Mean VO₂peak increased by 17% (SD 17.5). Participants reported increased leisure time physical activity and health-related quality of life, besides reduced fatigue.

Conclusion

Hybrid HIIT was safe for people with SCI paraplegia. The majority of the criteria for feasibility were met with acceptable attendance rate, limited drop out, participants enjoyed training, and increased VO₂peak and mean watts. However, the intensity of 90% peak watts was reached by < 60% of the participants despite high RPE ratings during training. The method of measuring and calculating intensity needs to be studied further before a study using this HIIT protocol is undertaken.

Trial registration

Clinicaltrials.gov, NCT04211311, registered 12 December 2019 retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-00997-2.

Air variability in maxillary sinus during radiotherapy for sinonasal carcinoma

INTRODUCTION

The aim was to characterise patterns and predictability of aeration changes in the ipsilateral maxillary sinus during intensity-modulated radiotherapy (IMRT) for sinonasal cancer (SNC), and in a sample evaluate the dosimetric effects of aeration changes for both photon and proton therapy.

MATERIALS AND METHODS

The study included patients treated with IMRT for SNC in a single institution in 2009-2017. The volume of air in the ipsilateral maxillary sinus was recorded in 1578 daily cone beam computer tomography (CBCT) from 53 patients. Patterns of changing air volumes were categorised as 'stable', increasing', 'decreasing', or 'erratic'. For the prediction analysis, categorisation was performed based both on the entire treatment course and the first five fractions (F1-5). Photon and proton therapy plans were generated for four patients, the one from each category with the largest aeration variation. Synthetic CT images were generated for each CBCT and all plans were recalculated on the daily synthetic CTs.

RESULTS

The absolute volume of air varied considerably during the treatment course, ranging from 0 to 25.9 cm3. Changes within a single participant varied in the range of 0-18.7 cm3. In the categorisation of patterns, most patients had increasing aeration of the sinus. Generally, patterns of aeration could not be predicted from F1-5. Patients categorised as increasing in F1-5 had the best prediction, with 78% predicted correctly as increasing for the entire treatment course. The numeric correlation coefficients for target coverage and air volume were low for 3/4 scenarios (photons 0.03-0.23, protons 0.26-0.48). No straightforward correlation between the dosimetric effect and the volume changes could be detected in the sample test of four patients for neither photon nor proton therapy.

CONCLUSION

The variation of aeration was large and unpredictable. No clear dosimetric consequences of the aeration variation were evident for neither IMRT nor proton therapy for the patients investigated.

Social isolation induces hyperactivity and exploration in aged female mice

Prolonged social isolation is associated with poor physical and mental health outcomes, findings observed in both humans, and rodent models of isolation. Humans, like mice, may engage in enhanced exploratory and social behaviour following isolation, which may protect against subsequent cognitive decline and psychological distress. Understanding how these effects may impact behaviour in older adults is particularly relevant, as this population is likely to experience periods of late-life social isolation. We report that late-life social isolation in female mice did not lead to robust depressive-like symptomology, altered social interaction behaviour, sensitivity to context fear acquisition and memory, or alterations in inflammatory cytokines (IL-6, IL-1β, Tnf-α) or microglial activation (Itgam) within the hippocampus. Rather, isolation increased hyperactivity and exploration behaviours. These findings have translational value as the first female mouse model of late-life social isolation, and provide evidence to inform the development of interventions aimed at promoting functional recovery following isolation in late-life.

Thermographic visualization of facial vasoconstriction is associated with 30-day all-cause mortality in medical patients; prospective observational two-site cohort study

INTRODUCTION

Quick and reliable assessment of acute patients is required for accurate triage. The temperature gradient between core and peripheral temperature could possibly instantly provide information on circulatory status.

METHODS

Adult medical patients, who did not receive supplementary oxygen, attending two emergency departments, had a thermographic image taken on arrival. The association between 30-day mortality and gradients was tested using logistic regression.

RESULTS

726 patients were studied, median age was 64 years and 14 (1.9%) died within 30 days. There was a significant association between mortality and temperature gradient, comparable to vital signs, age, and clinical intuition.

CONCLUSION

Temperature gradient between nose and eye had an acceptable discriminatory power for 30-day all-cause mortality.

Hemoglobin level at stabilization is associated with long-term all-cause mortality in patients with left-sided endocarditis, a POET substudy

Background

Left-sided infectious endocarditis (IE) has a high 1-year mortality. Anemia is a common finding in patients with IE, yet little is known about frequency, severity, and associated outcomes in this setting.

Purpose

To examine the relationship between Hemoglobin (Hgb) level measured at IE stabilization (time of randomization) in the Partial Oral versus intravenous Antibiotic Treatment of Endocarditis (POET) trial - and long-term all-cause mortality.

Methods

In the POET trial, 400 patients with left-sided IE were randomized, after medical and/or surgical stabilization, to conventional antibiotic treatment or partial oral treatment. Only non-surgically treated patients were considered in this study. Patients were divided by quartiles into four groups based on Hgb level at randomization.

Results

We examined 248 patients with non-surgically treated IE. Median time from diagnosis of IE to randomization was 14 days (IQ 12–19). At long-term follow-up (median 3.2 years, IQ 2.18–4.60), 71 patients had died (28.6%). Patients in the lowest quantile (Hgb ≤6.0 mmol) had a HR of 4.17 (95% CI 1.81–9.61, p&lt;0.001) for death compared to patients in the highest quantile (Hgb &gt;7.5 mmol/L). This association remained significant after multivariable adjustment for age, sex, renal disease, C-Reactive Protein, and Prosthetic heart valve (HR 2.69, 95% CI 1.11–6.50); p=0.028).

Conclusion

Low Hemoglobin level at stabilization in patients with IE was associated with an increased risk of long-term mortality. Whether intensified treatment of anemia in patients with IE could improve long-term outcome requires investigation.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): The Danish Heart Foundation, The Capital Regions Research Council

Late toxicity in the brain after radiotherapy for sinonasal cancer: Neurocognitive functioning, MRI of the brain and quality of life

•

Compared with matched normative data, impaired cognitive function was substantial.

•

Several correlations between radiation dose and cognitive impairment were present.

•

Radiation-induced white matter hyperintensities were present in 2/27 participants.

•

One participant displayed radiation-induced necrosis in the temporal lobe.

•

The domains affecting quality of life the most were fatigue and quality of sleep.

Purpose

The aim of the study was to evaluate neurocognitive late effects, structural alterations and associations between cognitive impairment and radiation doses as well as cerebral tissue damage after radiotherapy for sinonasal cancer. Furthermore, the aim was to report quality of life (QoL) and self-reported cognitive capacity.

Materials and methods

Recurrence-free patients previously treated with intensity-modulated radiotherapy with a curative intent were eligible for the study. Study examinations comprised comprehensive neurocognitive testing, MRI of the brain, and self-reported outcomes.

Results

A total of 27 patients were included. Median age was 67 years (range 47–83). The majority of test outcomes were below normative values in any degree, and 37% of the participants had clinically significant neurocognitive impairment when compared with normative data. Correlations between absorbed doses to specific substructures of the brain and neurocognitive outcomes were present for Wechsler’s Adult Intelligence Scale-digit span and Controlled Oral Word Association Test-S. Structural MRI revealed macroscopic abnormalities in three patients; infarction (n = 1), diffuse white matter intensities (n = 2) and necrosis (n = 1). In the analysis of atrophy of cerebral tissue, no correlations were present with neither radiation dose to cerebral substructures nor neurocognitive impairment. The global QoL of the cohort was 75. The most affected outcomes were ‘fatigue’, ‘insomnia’, and ‘drowsiness’. A total of 59% of participants reported significantly impaired quality of sleep. Self-reported cognitive function revealed that ‘memory’ was the most affected cognitive domain. For the domains of ‘memory’ and ‘language’, self-reported functioning was associated with objectively measured neurocognitive outcomes.

Conclusion

Cerebral toxicity after radiotherapy for sinonasal cancer was substantial. Clinically significant cognitive impairment was present in more than one third of the participants, and several dose–response associations were present. Furthermore, the presence of macroscopic radiation sequelae indicated considerable impact of radiotherapy on brain tissue.

Grazing mediates soil microbial activity and litter decomposition in salt marshes

Salt marshes contribute to climate change mitigation because of their great capacity to store organic matter (OM) in soils. Most of the research regarding OM turnover in salt marshes in times of global change focuses on effects of rising temperature and accelerated sea-level rise, while effects of land-use change have gained little attention. The present work investigates the mechanisms by which livestock grazing can affect OM decomposition in salt marsh soils. In a grazing exclusion experiment at the mouth of the Yangtze estuary, China, we assessed soil microbial exo-enzyme activity (EEA) to gain insight into the microbial carbon (C) and nitrogen (N) demand. Additionally, we studied the decomposition of plant litter in soil using the Tea Bag Index (TBI), a widely used standardized litter bag assay to fingerprint soil decomposition dynamics. Based on EEAs, grazing markedly reduced microbial C acquisition, whereas microbial N acquisition was strongly increased. These opposing grazing effects were also evident in the decomposition of standardized plant litter: The decomposition rate constant (k) and the stabilization (S) of litter were not inversely related, as would be expected, but instead both were reduced by livestock grazing. Our data suggest that gazing effects on EEAs and litter decomposition can just partly be explained by grazing-driven soil compaction and resulting lower oxygen availability, which has previously been hypothesized as a main pathway by which grazing can reduce microbial activity in wetland soils. Instead, grazing effects on microbial nutrient demand occurs to be an at least equally important control on soil decomposition processes.

Four New Species of Paraorygmatobothrium (Eucestoda: Phyllobothriidea) From Sharks of the Gulf of Mexico and the Atlantic Ocean, with Comments on Their Host Specificity

Four new species of Paraorygmatobothrium are described from carcharhinid shark species from the Gulf of Mexico and the U.S. coast of the northwestern Atlantic Ocean. Paraorygmatobothrium bullardi n. sp. is described from Carcharhinus brevipinna as its type host, and from Carcharhinus acronotus and Carcharhinus limbatus. Paraorygmatobothrium campbelli n. sp. is described from Rhizoprionodon terraenovae. Paraorygmatobothrium deburonae n. sp. is described from Carcharhinus isodon as its type host, as well as from C. brevipinna, C. limbatus, and R. terraenovae. Paraorygmatobothrium mattisi n. sp. is described from R. terraenovae as its type host, and from C. brevipinna and C. limbatus. These 4 species differ from other species of Paraorygmatobothrium and from each other in bothridial microthrix shape, and in various combinations of features such as the total length of the worm, apical sucker size, bothridial musculature, proglottid number, testes number, and genital pore position. Difficulty in differentiating these 4 species from one another, and from other species of Paraorygmatobothrium, points to limitations in the use of morphology alone to recognize species diversity in this genus. A phylogenetic analysis of Paraorygmatobothrium and related genera, based on partial (D1-D3) 28S rDNA sequence data, confirms that the genus is not monophyletic. Genetic distances of COI revealed that sequence divergence between species of Paraorygmatobothrium is generally at least an order of magnitude larger than COI divergence within a species. Patterns of host use for 3 of the new species are consistent with previous findings that point to a lack of host specificity in Paraorygmatobothrium.

Interactive website for head and neck cancer patients: Adherence and coping program to prevent dysphagia after radiation

INTRODUCTION

Pharyngeal and laryngeal cancers are highly curable; however survivors are at high risk for long-term dysphagia after radiation. To address lack of access to preventive care in community settings, we developed a responsive web-based application to help patients adhere to preventive swallowing exercises and cope with radiation side effects. We conducted an interim study analysis to determine website usage characteristics and to examine the effect size for future trials.

METHODS

Pharyngeal and laryngeal cancer patients were recruited for enrollment by speech language pathologists before primary radiation and introduced to the interactive website. The program (English and Spanish) features tracking logs for preventive exercises, instructional videos, patient stories and search features. Patients' self-reported swallowing function was assessed with the MD Anderson Dysphagia Inventory (MDADI) at baseline and at 6 months. Adherence to preventive exercises was assessed during the 10 week intervention. Number of unique website visits, total duration of website exposure, and rankings of the most popular webpages were calculated. Preliminary regression models were run using adherence and MDADI as outcomes.

RESULTS

Of the 160 enrolled, 96 had 10-week adherence data and 61 had 6-month MDADI data. The average age was 63 (SD = 12.26), 49.4% were from rural counties, 44% had a high school education or lower, and 42% reported annual income of $30,000 or less. The average number of visits was 5.49 (SD = 9.96) and the average total time spent with the website was 41.09 min (SD =88.48). Preliminary analyses indicated that number of unique visits to the website was independently associated with increased adherence to preventive exercises (p = .001-.008).

CONCLUSION

Our website showed significant effects in promoting adherence to swallowing exercises. However, our return visit rate showed that the platform needs improvement in navigability and usability for this older population undergoing challenging treatment in community settings with low resources.

NTCP model validation method for DAHANCA patient selection of protons versus photons in head and neck cancer radiotherapy

Introduction: Prediction models using logistic regression may perform poorly in external patient cohorts. However, there is a need to standardize and validate models for clinical use. The purpose of this project was to describe a method for validation of external NTCP models used for patient selection in the randomized trial of protons versus photons in head and neck cancer radiotherapy, DAHANCA 35. Material and methods: Organs at risk of 588 patients treated primarily with IMRT in the randomized controlled DAHANCA19 trial were retrospectively contoured according to recent international recommendations. Dose metrics were extracted using MatLab and all clinical parameters were retrieved from the DAHANCA database. The model proposed by Christianen et al. to predict physician-rated dysphagia was validated through the closed testing, where change of the model intercept, slope and individual beta's were tested for significant prediction improvements. Results: Six months prevalence of dysphagia in the validation cohort was 33%. The closed testing procedure for physician-rated dysphagia showed that the Christianen et al. model needed an intercept refitting for the best match for the Danish patients. The intercept update increased the risk of dysphagia for the validation cohort by 7.9 ± 2.5% point. For the raw model performance, the Brier score (mean squared residual) was 0.467, which improved significantly with a new intercept to 0.415. Conclusions: The previously published Dutch dysphagia model needed an intercept update to match the Danish patient cohort. The implementation of a closed testing procedure on the current validation cohort allows quick and efficient validation of external NTCP models for patient selection in the future.

Exercise-based cardiac rehabilitation in patients with reduced left ventricular ejection fraction: The Cardiac Rehabilitation Outcome Study in Heart Failure (CROS-HF): A systematic review and meta-analysis

Background

In heart failure with reduced left ventricular ejection fraction (HFrEF) patients the effects of exercise-based cardiac rehabilitation on top of state-of-the-art pharmacological and device therapy on mortality, hospitalization, exercise capacity and quality-of-life are not well established.

Design

The design of this study involved a structured review and meta-analysis.

Methods

Evaluation of randomised controlled trials of exercise-based cardiac rehabilitation in HFrEF-patients with left ventricular ejection fraction ≤40% of any aetiology with a follow-up of ≥6 months published in 1999 or later.

Results

Out of 12,229 abstracts, 25 randomised controlled trials including 4481 HFrEF-patients were included in the final evaluation. Heterogeneity in study population, study design and exercise-based cardiac rehabilitation-intervention was evident. No significant difference in the effect of exercise-based cardiac rehabilitation on mortality compared to control-group was found (hazard ratio 0.75, 95% confidence interval 0.39–1.41, four studies; 12-months follow-up: relative risk 1.29, 95% confidence interval 0.66–2.49, eight studies; six-months follow-up: relative risk 0.91, 95% confidence interval 0.26–3.16, seven studies). In addition there was no significant difference between the groups with respect to ‘hospitalization-for-any-reason’ (12-months follow-up: relative risk 0.79, 95% confidence interval 0.41–1.53, four studies), or ‘hospitalization-due-to-heart-failure’ (12-months follow-up: relative risk 0.59, 95% confidence interval 0.12–2.91, four studies; six-months follow-up: relative risk 0.84, 95% confidence interval 0.07–9.71, three studies). All studies show improvement of exercise capacity. Participation in exercise-based cardiac rehabilitation significantly improved quality-of-life as evaluated with the Kansas City Cardiomyopathy Questionnaire: (six-months follow-up: mean difference 1.94, 95% confidence interval 0.35–3.56, two studies), but no significant results emerged for quality-of-life measured by the Minnesota Living with Heart Failure Questionnaire (nine-months or more follow-up: mean difference –4.19, 95% confidence interval –10.51–2.12, seven studies; six-months follow-up: mean difference –5.97, 95% confidence interval –16.17–4.23, four studies).

Conclusion

No association between exercise-based cardiac rehabilitation and mortality or hospitalisation could be observed in HFrEF patients but exercise-based cardiac rehabilitation is likely to improve exercise capacity and quality of life.

A New Species of Pentaloculum (Cestoda: "Tetraphyllidea") from the Taiwan Saddled Carpetshark, Cirrhoscyllium formosanum (Orectolobiformes: Parascylliidae)

Collection of cestodes from the Taiwan saddled carpetshark, Cirrhoscyllium formosanum, for the first time led to the discovery of Pentaloculum hoi n. sp. This species provided important insights into the identity of the heretofore monotypic Pentaloculum-known previously only from the blind electric ray, Typhlonarke aysoni, in New Zealand. The new species differs from Pentaloculum macrocephalum in testis number, vitelline follicle and cirrus sac configuration, and in that it is hyperapolytic rather than euapolytic. Maximum-likelihood analysis of sequence data generated for the D1-D3 region of the 28S rDNA gene not only confirmed this generic placement but also confirmed the close affinities between both species of Pentaloculum and specimens previously referred to in the literature as new genus 7 n. sp. 1. Examination of limited material of the latter, including that of a second specimen from which partial 28S rDNA sequence data were generated here, led to the realization that new genus 7 n. sp. 1 represents an undescribed species of Pentaloculum, referred to here as Pentaloculum n. sp. 2. All 3 species share bothridia divided into 1 anterior and 2 consecutive pairs of loculi. Given that Pentaloculum n. sp. 2 parasitizes a member of the second and only other genus of parascylliid sharks (i.e., Parascyllium), we predict that the 4 other species of Parascyllium and the 2 other species of Cirrhoscyllium are likely to host other species of Pentaloculum. The factors that might account for the eclectic host associations of Pentaloculum, which include a torpediniform ray and 2 species of orectilobiform sharks, are currently unclear. The compilation of diet data for these elasmobranchs and determination of the final intermediate hosts for these cestodes would be interesting avenues of further investigation given that cestodes are trophically transmitted between their intermediate and definitive hosts. The phylogenetic affinities of Pentaloculum among elasmobranch cestodes remain unresolved.

A New Genus of Tapeworm (Cestoda: Onchoproteocephalidea) from Sawfish (Elasmobranchii: Pristidae)

Collections from the dwarf sawfish, Pristis clavata, near Darwin, Australia, in 1997 led to the discovery of the new onchoproteocephalidean genus Matticestus n. gen.-a taxon that has been referred to in molecular phylogenetic analyses in which it has been included as "New genus 8." Its type species, Matticestus anneae n. gen., n. sp., and a second species, Matticestus kathleenae n. sp., are described. Placement of this taxon in the Onchoproteocephalidea is supported morphologically in that both species bear a scolex with 4 bothridia each with a pair of bi-pronged hooks and spinitriches that extend throughout the length of the body. Sequence data for the D1-D3 region of the 28S rDNA gene also place the genus solidly among the other elasmobranch-hosted members of the order. The new genus differs from the other elasmobranch-hosted genera in the order in that its members possess a combination of biloculated bothridia with lateral lappets on the posterior margin of the anterior loculus and a pair of bi-pronged hooks with a distinctive configuration of tubercles and internal channels. Its members are also extremely small. In summary, Matticestus n. gen. is an unusually tiny, "spiny," genus of cestode that seems to exclusively parasitize sawfish of the genus Pristis.

Abstract 3355: Identification of a novel network of miRNAs that regulate stemness in colorectal cancer

Background and Aims: Accumulating evidence suggests that a subset of cancer cells also known as the “cancer stem cells” (CSCs) influence various clinical outcomes in cancer, including tumor recurrence, metastasis and resistance to chemotherapy. Recently stemness has been recognized as a dynamic state governed by epigenetic modifiers including miRNAs. Despite identification of several self-renewal associated miRNAs, miRNA profile of CSCs remains unclear. Herein, we characterized miRNA expression of CSCs with high vs. low CD44v6 expression through RNA-Seq. Subsequently, we investigated the clinical significance of a novel miRNA identified from this systematic discovery approach.

Methods: Colorectal CSCs from HCT116 and HT29 cells were grown as spheroid-derived cancer stem cells (SDCSCs). CD44v6+ and CD44v6- CSCs were subdivided by FACS and characterized by small RNA-Seq. Differentially expressed miRNAs were subsequently confirmed in CD44v6+ CSCs and chemoresistant cells. The expression of one such candidate, miR-1246, was assessed in a clinical cohort (n = 144) by qRT-PCR.

Results: MiRNA profiling identified a unique overall pattern of CD44v6+ SDCSCs indicative of high self-renewal capacity. We noted that a panel of established self-renewal suppressive-miRNAs were downregulated (including miR-34a, 101 and 200 family) in CD44v6+ CSCs, and discovered upregulation of previously unreported miRNAs (miR-1246, 3605, 3182 and 4284). KEGG pathway analysis indicated that these miRNAs regulate Akt-MAPK and Wnt signaling pathways. Subsequently, we selected miR-1246 and validated its expression in CD44v6+ SDCSCs and chemoresistant cells. Clinically, the expression of miR-1246 was significantly elevated in CRC tissues compared to corresponding normal mucosa, and this occurred in a stage-dependent manner in primary CRCs. Furthermore, the expression of CD44v6 positively correlated with miR-1246 in CRC tissues. High miR-1246 expression resulted in poor disease free and overall survival.

Conclusion: Using a systematic and comprehensive approach, we have identified a unique network of dysregulated miRNAs in CD44v6 CSCs indicative of high degree of stemness features in cancer. In particular, we identified miR-1246 to be frequently overexpressed in CSCs as well as chemoresistant cells and its expression was associated with poor prognosis in CRC patients. Collectively, we have identified a unique group of previously unreported miRNAs which appear to have important mechanistic roles in CSCs and could serve as a promising predictive biomarkers for recurrence and prognosis in patients with CRC.

Citation Format: Shusuke Toden, Takatoshi Matsuyama, Elizabeth Hutchins, Kendall Jensen, Ajay Goel. Identification of a novel network of miRNAs that regulate stemness in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3355. doi:10.1158/1538-7445.AM2017-3355

Predictors of overall and recurrence-free survival after neoadjuvant chemotherapy for gastroesophageal adenocarcinoma: Pooled analysis of individual patient data (IPD) from randomized controlled trials (RCTs)

BACKGROUND

Neoadjuvant chemotherapy improves prognosis of patients with locally advanced gastroesophageal adenocarcinoma. The aim of this study was to identify predictors for postoperative survival following neoadjuvant therapy. These could be useful in deciding about postoperative continuation of chemotherapy.

METHODS

This meta-analysis used IPD from RCTs comparing neoadjuvant chemotherapy with surgery alone for gastroesophageal adenocarcinoma. Trials providing IPD on age, sex, performance status, pT/N stage, resection status, overall and recurrence-free survival were included. Survival was calculated in the entire study population and subgroups stratified by supposed predictors and compared using the log-rank test. Multivariable Cox models were used to identify independent survival predictors.

RESULTS

Four RCTs providing IPD from 553 patients fulfilled the inclusion criteria. (y)pT and (y)pN stage and resection status strongly predicted postoperative survival both after neoadjuvant therapy and surgery alone. Patients with R1 resection after neoadjuvant therapy survived longer than those with R1 resection after surgery alone. Patients with stage pN0 after surgery alone had better prognosis than those with ypN0 after neoadjuvant therapy. Patients with stage ypT3/4 after neoadjuvant therapy survived longer than those with stage pT3/4 after surgery alone. Multivariable regression identified resection status and (y)pN stage as predictors of survival in both groups. (y)pT stage predicted survival only after surgery alone.

CONCLUSION

After neoadjuvant therapy for gastroesophageal adenocarcinoma, survival is determined by the same factors as after surgery alone. However, ypT stage is not an independent predictor. These results can facilitate the decision about postoperative continuation of chemotherapy in pretreated patients.