One-dimensional proximity superconductivity in the quantum Hall regime

Extensive efforts have been undertaken to combine superconductivity and the quantum Hall effect so that Cooper-pair transport between superconducting electrodes in Josephson junctions is mediated by one-dimensional edge states1-6. This interest has been motivated by prospects of finding new physics, including topologically protected quasiparticles7-9, but also extends into metrology and device applications10-13. So far it has proven challenging to achieve detectable supercurrents through quantum Hall conductors2,3,6. Here we show that domain walls in minimally twisted bilayer graphene14-18 support exceptionally robust proximity superconductivity in the quantum Hall regime, allowing Josephson junctions to operate in fields close to the upper critical field of superconducting electrodes. The critical current is found to be non-oscillatory and practically unchanging over the entire range of quantizing fields, with its value being limited by the quantum conductance of ballistic, strictly one-dimensional, electronic channels residing within the domain walls. The system described is unique in its ability to support Andreev bound states at quantizing fields and offers many interesting directions for further exploration.

Single-cell genomics and regulatory networks for 388 human brains

Single-cell genomics is a powerful tool for studying heterogeneous tissues such as the brain. Yet, little is understood about how genetic variants influence cell-level gene expression. Addressing this, we uniformly processed single-nuclei, multi-omics datasets into a resource comprising >2.8M nuclei from the prefrontal cortex across 388 individuals. For 28 cell types, we assessed population-level variation in expression and chromatin across gene families and drug targets. We identified >550K cell-type-specific regulatory elements and >1.4M single-cell expression-quantitative-trait loci, which we used to build cell-type regulatory and cell-to-cell communication networks. These networks manifest cellular changes in aging and neuropsychiatric disorders. We further constructed an integrative model accurately imputing single-cell expression and simulating perturbations; the model prioritized ~250 disease-risk genes and drug targets with associated cell types.

Practice and principles of stereotactic body radiation therapy for spine and non-spine bone metastases

Radiotherapy is the dominant treatment modality for painful spine and non-spine bone metastases (NSBM). Historically, this was achieved with conventional low dose external beam radiotherapy, however, stereotactic body radiotherapy (SBRT) is increasingly applied for these indications. Meta-analyses and randomized clinical trials have demonstrated improved pain response and more durable tumor control with SBRT for spine metastases. However, in the setting of NSBM, there is limited evidence supporting global adoption and large scale randomized clinical trials are in need. SBRT is technically demanding requiring careful consideration of organ at risk tolerance, and strict adherence to technical requirements including immobilization, simulation, contouring and image-guidance procedures. Additional considerations include follow up practices after SBRT, with appropriate imaging playing a critical role in response assessment. Finally, there is renewed research into promising new technologies that may further refine the use of SBRT in both spinal and NSBM in the years to come.

HyenaDNA: Long-Range Genomic Sequence Modeling at Single Nucleotide Resolution

Genomic (DNA) sequences encode an enormous amount of information for gene regulation and protein synthesis. Similar to natural language models, researchers have proposed foundation models in genomics to learn generalizable features from unlabeled genome data that can then be fine-tuned for downstream tasks such as identifying regulatory elements. Due to the quadratic scaling of attention, previous Transformer-based genomic models have used 512 to 4k tokens as context (<0.001% of the human genome), significantly limiting the modeling of long-range interactions in DNA. In addition, these methods rely on tokenizers or fixed k-mers to aggregate meaningful DNA units, losing single nucleotide resolution where subtle genetic variations can completely alter protein function via single nucleotide polymorphisms (SNPs). Recently, Hyena, a large language model based on implicit convolutions was shown to match attention in quality while allowing longer context lengths and lower time complexity. Leveraging Hyena's new long-range capabilities, we present HyenaDNA, a genomic foundation model pretrained on the human reference genome with context lengths of up to 1 million tokens at the single nucleotide-level - an up to 500x increase over previous dense attention-based models. HyenaDNA scales sub-quadratically in sequence length (training up to 160x faster than Transformer), uses single nucleotide tokens, and has full global context at each layer. We explore what longer context enables - including the first use of in-context learning in genomics. On fine-tuned benchmarks from the Nucleotide Transformer, HyenaDNA reaches state-of-the-art (SotA) on 12 of 18 datasets using a model with orders of magnitude less parameters and pretraining data. On the GenomicBenchmarks, HyenaDNA surpasses SotA on 7 of 8 datasets on average by +10 accuracy points. Code at https://github.com/HazyResearch/hyena-dna.

High Resolution Imaging with Focused kV X-Rays for Small Animal Radio-Neuromodulation

PURPOSE/OBJECTIVE(S)

High precision radiotherapy for small animal radio-neuromodulation requires conformal treatment to very small targets down to 2.5 mm. A focused kV technique based on novel usage of polycapillary x-ray lenses can focus x-ray beams to <0.2 mm in diameter, which is ideal for such uses. Such application also requires high resolution CT images for treatment planning and setup, which was hard to achieve using conventional x-ray tube. In this work, we demonstrate the feasibility of using a virtual focal spot generated with an x-ray lens to perform high-resolution CBCT acquisition.

MATERIALS/METHODS

The experiment with x-ray lens was set up on an x-ray tabletop system to generate a virtual focal spot. A pinhole image was acquired for the virtual focal spot and compared with the one acquired with the conventional focal spot without the lens. The planar imaging resolution with and without the lens were evaluated using a line pair resolution phantom. The spatial resolution of the two settings were estimated by reconstructing a 0.15-mm wire phantom and comparing its full width half maximum (FWHM). A CBCT scan of a rodent head was also acquired to further demonstrate the improved resolution using the x-ray lens.

RESULTS

Compared to conventional imaging acquisition with a measured x-ray focal spot of 0.395 mm FWHM, the virtual focal spot size was measured at 0.175 mm. The reduction in focal spot size with lens leads to an almost doubled planar imaging resolution and a 26% enhancement in 3D spatial resolution. A realistic CBCT acquisition of a rodent head mimicked the imaging acquisition step for radio-neuromodulation and further showed the improved visualization for fine structures.

CONCLUSION

This work demonstrated that the focused kV x-ray technique was capable of generating small focal spot size of <0.2 mm. The proposed method provides an adaptive imaging platform to acquire x-ray and CBCT images for treatment planning and setup with improved spatial resolution compared to conventional CBCT image acquisition.

High resolution imaging with focused kV x-rays for small animal radio-neuromodulation

BACKGROUND

High precision radiotherapy with small irradiator size has potential in many treatment applications involving small shallow targets, with small animal radio-neuromodulation as an intriguing example. A focused kV technique based on novel usage of polycapillary x-ray lenses can focus x-ray beams to <0.2 mm in diameter, which is ideal for such uses.

PURPOSE

Such an application also requires high resolution CT images for treatment planning and setup. In this work, we demonstrate the feasibility of using a virtual focal spot generated with an x-ray lens to perform high-resolution CBCT acquisition.

METHOD

The experiment with x-ray lens was set up on an x-ray tabletop system to generate a virtual focal spot. The flood field images with and without the x-ray lens were first compared. A pinhole image was acquired for the virtual focal spot and compared with the one acquired with the conventional focal spot without the lens. The planar imaging resolution with and without the lens were evaluated using a line pair resolution phantom. The spatial resolution of the two settings were estimated by reconstructing a 0.15-mm wire phantom and comparing its full width half maximum (FWHM). A CBCT scan of a rodent head was also acquired to further demonstrate the improved resolution using the x-ray lens.

RESULT

The proposed imaging setup with x-ray lens had a limited exposure area of 5 cm by 5 cm on the detector, which was suitable for guiding radio-neuromodulation to a small target in rodent brain. Compared to conventional imaging acquisition with a measured x-ray focal spot of 0.395 mm FWHM, the virtual focal spot size was measured at 0.175 mm. The reduction in focal spot size with lens leads to an almost doubled planar imaging resolution and a 26% enhancement in 3D spatial resolution. A realistic CBCT acquisition of a rodent head mimicked the imaging acquisition step for radio-neuromodulation and further showed the improved visualization for fine structures.

CONCLUSION

This work demonstrated that the focused kV x-ray technique was capable of generating small focal spot size of <0.2 mm, which substantially improved x-ray imaging resolution for small animal imaging.

Protocol to generate endothelial cells, pericytes, and fibroblasts in one differentiation round from human-induced pluripotent stem cells

Here, we present a protocol for differentiating human-induced pluripotent stem cells into three distinct mesodermal cell types: vascular endothelial cells (ECs), pericytes, and fibroblasts. We describe steps for using monolayer serum-free differentiation and isolating ECs (CD31⁺) and mesenchymal pre-pericytes (CD31^-) from a single differentiation set. We then differentiate pericytes into fibroblasts using a commercial fibroblast culture medium. The three cell types differentiated in this protocol are useful for vasculogenesis, drug testing, and tissue engineering applications. For complete details on the use and execution of this protocol, please refer to Orlova et al. (2014).¹.

Bioprinted 3D outer retina barrier uncovers RPE-dependent choroidal phenotype in advanced macular degeneration

Age-related macular degeneration (AMD), a leading cause of blindness, initiates in the outer-blood-retina-barrier (oBRB) formed by the retinal pigment epithelium (RPE), Bruch's membrane, and choriocapillaris. The mechanisms of AMD initiation and progression remain poorly understood owing to the lack of physiologically relevant human oBRB models. To this end, we engineered a native-like three-dimensional (3D) oBRB tissue (3D-oBRB) by bioprinting endothelial cells, pericytes, and fibroblasts on the basal side of a biodegradable scaffold and establishing an RPE monolayer on top. In this 3D-oBRB model, a fully-polarized RPE monolayer provides barrier resistance, induces choriocapillaris fenestration, and supports the formation of Bruch's-membrane-like structure by inducing changes in gene expression in cells of the choroid. Complement activation in the 3D-oBRB triggers dry AMD phenotypes (including subRPE lipid-rich deposits called drusen and choriocapillaris degeneration), and HIF-α stabilization or STAT3 overactivation induce choriocapillaris neovascularization and type-I wet AMD phenotype. The 3D-oBRB provides a physiologically relevant model to studying RPE-choriocapillaris interactions under healthy and diseased conditions.

Impacted gallstone within a cholecystoduodenal fistula: endoscopic laser lithotripsy to the rescue

Video 1A large, impacted gallstone is treated unsuccessfully with electrohydraulic lithotripsy; however, fragmentation and removal is accomplished using endoscopic laser lithotripsy.

Pathological characterization of a novel mouse model expressing the PD-linked CHCHD2-T61I mutation

Coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2) is a mitochondrial protein that plays important roles in cristae structure, oxidative phosphorylation and apoptosis. Multiple mutations in CHCHD2 have been associated with Lewy body disorders (LBDs), such as Parkinson's disease (PD) and dementia with Lewy bodies, with the CHCHD2-T61I mutation being the most widely studied. However, at present, only CHCHD2 knockout or CHCHD2/CHCHD10 double knockout mouse models have been investigated. They do not recapitulate the pathology seen in patients with CHCHD2 mutations. We generated the first transgenic mouse model expressing the human PD-linked CHCHD2-T61I mutation driven by the mPrP promoter. We show that CHCHD2-T61I Tg mice exhibit perinuclear mitochondrial aggregates, neuroinflammation, and have impaired long-term synaptic plasticity associated with synaptic dysfunction. Dopaminergic neurodegeneration, a hallmark of PD, is also observed along with α-synuclein pathology. Significant motor dysfunction is seen with no changes in learning and memory at 1 year of age. A minor proportion of the CHCHD2-T61I Tg mice (~10%) show a severe motor phenotype consistent with human Pisa Syndrome, an atypical PD phenotype. Unbiased proteomics analysis reveals surprising increases in many insoluble proteins predominantly originating from mitochondria and perturbing multiple canonical biological pathways as assessed by ingenuity pathway analysis, including neurodegenerative disease-associated proteins such as tau, cofilin, SOD1 and DJ-1. Overall, CHCHD2-T61I Tg mice exhibit pathological and motor changes associated with LBDs, indicating that this model successfully captures phenotypes seen in human LBD patients with CHCHD2 mutations and demonstrates changes in neurodegenerative disease-associated proteins, which delineates relevant pathological pathways for further investigation.

hTERT DNA Methylation Analysis Identifies a Biomarker for Retinoic Acid-Induced hTERT Repression in Breast Cancer Cell Lines

Telomerase reactivation is responsible for telomere preservation in about 90% of cancers, providing cancer cells an indefinite proliferating potential. Telomerase consists of at least two main subunits: a catalytic reverse transcriptase protein (hTERT) and an RNA template subunit. Strategies to inhibit hTERT expression seem promising for cancer treatment. Previous works showed that all-trans retinoic acid (ATRA) induces hTERT repression in acute promyelocytic leukemia cells, resulting in their death. Here, we investigated the effects of ATRA in a subset of breast cancer cell lines. The mutational status of hTERT promoter and the methylation patterns at a single CpG resolution were assessed. We observed an inverse relationship between hTERT expression after ATRA treatment and the methylation level of a specific CpG at chr5: 1,300,438 in a region of hTERT gene at −5 kb of the transcription initiation site. This observation highlighted the significance of this region, whose methylation profile could represent a promising biomarker to predict the sensitivity to ATRA-induced hTERT repression in specific breast cancer subtypes. As hTERT repression promotes drug-induced cell death, checking the methylation status of this unique region and the specific CpG included can help in decision-making to include ATRA in combination therapy and contributes to a better clinical outcome.

P103 Impact of the COVID-19 pandemic on the sleep of patients of a multidisciplinary sleep clinic

Introduction

This study aimed to assess the impact of the COVID-19 pandemic on the sleep of adult patients of a multidisciplinary sleep clinic.

Methods

Patients were invited to complete online surveys: Survey 1 in October 2020 (increased COVID-19 restrictions) followed by Survey 2 in February 2021 (after easing of restrictions for a COVIDSafe summer).

Results

Of the 746 patients invited to participate, 73 completed and 8 partially returned Survey 1 (mean age 50.1 years, range 21–83 years, 58% female). Subsequently, 46 completed and 5 partially answered Survey 2. In Survey 1, 22/74 (29.7%) reported reduced sleep quantity and 31/75 (41.3%) indicated worse sleep quality compared with prior to the pandemic. In Survey 2, 33/46 (71.7%) described unchanged sleep quantity whilst 5/46 (10.9%) reported increased sleep quantity since easing COVID-19 restrictions. 36/46 (78.3%) indicated unchanged sleep quality whereas 5/46 (10.9%) described improved sleep quality since easing restrictions. However, 9/46 (19.6%) reported that their sleep remained worse compared with pre-pandemic. For patients who completed both surveys, there was no significant change in Insomnia Severity Index scores (Survey 1 mean 13.6, Survey 2 mean 12.9, mean difference -0.67 [95%CI -2.02, 0.68], p=0.32) or PROMIS Sleep-Related Impairment 8a T-scores (Survey 1 mean 59.0, Survey 2 mean 59.5, mean difference 0.44 [95%CI -1.55, 2.42], p=0.66).

Discussion

The COVID-19 pandemic has negatively affected the sleep of 44% of patients. Following easing of restrictions, symptoms of insomnia and sleep-related impairment did not change significantly, and 19.6% reported that their sleep was not back to their pre-pandemic baseline.

Clinical features and outcomes of neuroblastomas in adults

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Background: Neuroblastomas (NBs) are a spectrum of primitive tumors that include Esthesioneuroblastoma (ENB), and both neuroblastoma (NB) and ganglioneuroblastoma (GNB). NB and GNB are prevalent in children and rare in adults with a paucity of data on their therapy and outcomes. This review is to investigate the clinicopathologic features, treatment, and outcomes of NBs in adults. In addition, we highlight genomic findings of a 63-year-old man treated at our institution and discuss ALK-inhibition as a novel treatment strategy for ALK-driven adult-onset NB. Methods: PubMed literature search for NB adults (19+ years) for the period 2000 – 2020 pooled with a case from our institution. Results: Of the 163 included cases, 105 were ENB, 40 were NB, and 18 were GNB. Male:female ratio (1.50:1, 1.29:1, and 1.83:1 respectively). Mean age at diagnosis (49.8, 39.3, and 38.8 respectively). Most common primary site was sinonasal (60%) in ENB, retroperitoneal (20%) in NB, and adrenal (22%) in GNB. Metastasis found in 31.4%, 42.0%, and 16.7% with a mortality rate of 45%, 53%, and 33% respectively. Most common treatment modality overall was surgery with radiation in ENB (35%), Surgery with chemotherapy in NB (28%) and surgery alone in GNB (50%). Most common treatment modality in metastatic cases was surgery with chemoradiation in ENB (50%), surgery with chemotherapy in NB (36%), and surgery alone in GNB (33%). In our patient, ALK gene (R1275Q) gain of function mutation found both in molecular profiling and genomic circulating DNA analysis. Conclusions: Metastatic NB in adults is associated with very high mortality. Their rarity, heterogeneity of clinical behaviors, diverse treatment regimens, and variable outcomes make them even more challenging. The findings of this study would improve our understanding and develop multidisciplinary management strategies for this rare malignancy in adults. Moreover, further research focusing on the potential novel treatment with ALK-targeted inhibitors may hold promise to improve survival outcomes in adult-onset ALK-positive NB. [Table: see text]

Complex context relationships between DNA methylation and accessibility, histone marks, and hTERT gene expression in acute promyelocytic leukemia cells: perspectives for all-trans retinoic acid in cancer therapy

Telomerase (hTERT) reactivation and sustained expression is a key event in the process of cellular transformation. Therefore, the identification of the mechanisms regulating hTERT expression is of great interest for the development of new anticancer therapies. Although the epigenetic state of hTERT gene promoter is important, we still lack a clear understanding of the mechanisms by which epigenetic changes affect hTERT expression. Retinoids are well-known inducers of granulocytic maturation in acute promyelocytic leukemia (APL). We have previously shown that retinoids repressed hTERT expression in the absence of maturation leading to growth arrest and cell death. Exploring the mechanisms of this repression, we showed that transcription factor binding was dependent on the epigenetic status of hTERT promoter. In the present study, we used APL cells lines and publicly available datasets from APL patients to further investigate the integrated epigenetic events that promote hTERT promoter transition from its silent to its active state, and inversely. We showed, in APL patients, that the methylation of the distal domain of hTERT core promoter was altered and correlated with the outcome of the disease. Further studies combining complementary approaches carried out on APL cell lines highlighted the significance of a domain outside the minimal promoter, localized around 5 kb upstream from the transcription start site, in activating hTERT. This domain is characterized by DNA hypomethylation and H3K4Me3 deposition. Our findings suggest a cooperative interplay between hTERT promoter methylation, chromatin accessibility, and histone modifications that force the revisiting of previously proposed concepts regarding hTERT epigenetic regulation. They represent, therefore, a major advance in predicting sensitivity to retinoid-induced hTERT repression and, more generally, in the potential development of therapies targeting hTERT expression in cancers.

Anastomotic Breakdown Five Years After Neoadjuvant Radiochemotherapy and Ultralow Anterior Resection for Rectal Adenocarcinoma

For carefully selected patients with low-lying rectal cancers, ultralow anterior resection (ULAR) can be an effective alternative to abdominal perineal resection, and together with neoadjuvant radiochemotherapy can provide the opportunity for sphincter preservation. However, ULAR is not without potential postoperative complications, particularly anastomotic dehiscence which increases in likelihood after receiving radiation therapy. While surveillance imaging is not indicated three years beyond initial surgical resection, changes in chronic symptoms refractory to conservative management may warrant further investigation. In this case report, we present an interesting case of late-onset stenosis and anastomotic breakdown following neoadjuvant radiochemotherapy, ULAR, and coloanal anastomosis for a low-lying rectal adenocarcinoma. Effective patient education, reliable symptom assessment, and multidisciplinary collaboration are essential to assessing for long-term treatment-related complications and providing appropriate treatment in a timely manner.

Early Mobilization Post-Hip Fracture Surgery

Introduction:

Early mobilization after hip fracture surgery is a widely practiced component of postoperative care. However, there is little evidence to suggest that early mobilization post–hip fracture surgery is beneficial in reducing postoperative complications. This study aims to investigate the effect of early mobilization following hip fracture surgery on postoperative complications.

Materials and Methods:

This study retrospectively included 240 patients (female = 165, male = 75, mean age: 82.2 years) admitted to a level 1 trauma center in Adelaide, Australia, for hip fracture surgery. The effect of early mobilization on postoperative complications was assessed along with premorbid status. Subgroup analysis of patients stratified by premorbid health was subsequently analyzed to reduce confounding.

Results:

The odds of developing a complication were 1.9 times higher if the patient remained bedbound compared to mobilizing. Early mobilization was favorable to delayed mobilization. On average, complication-free patients mobilized earlier (mean [M] = 29 hours) compared to patients who experienced complications (M = 38 hours). In particular, rates of delirium was significantly reduced in patients who mobilized compared to remaining bedbound. However, premorbid status varied greatly. Early mobilizers had significantly better premorbid health than patients who remained bedbound. Overall subgroup analysis of patients with similar premorbid health showed mobilization was not associated with a reduction in complications. With an exception of patients with poor premorbid health, who experienced a reduction in complications following early mobilization.

Discussion:

In general, early mobilization was associated with the same complication rates as delayed mobilization and remaining bedbound. Patients with poor premorbid health benefited most from early mobilization with reduced complication rates.

Conclusion:

Postoperative delirium and premorbid health were better indicators of postoperative outcomes than time to mobilization.

Rethinking Intravenous Catheter Size and Location for Computed Tomography Pulmonary Angiography

Introduction

Computed tomography pulmonary angiography (CTPA) is the test of choice for diagnosis of pulmonary embolism (PE) in the emergency department (ED), but this test may be indeterminate for technical reasons such as inadequate contrast filling of the pulmonary arteries. Many hospitals have requirements for intravenous (IV) catheter size or location for CTPA studies to reduce the chances of inadequate filling, but there is a lack of clinical data to support these requirements. The objective of this study was to determine if a certain size or location of IV catheter used for contrast for CTPA is associated with an increased chance of suboptimal CTPA.

Methods

This was a retrospective chart review of patients who underwent CTPA in the ED. A CTPA study was considered suboptimal if the radiology report indicated it was technically limited or inadequate to exclude a PE. The reason for the study being suboptimal, and the size and location of the IV catheter, were abstracted. We calculated the rate of inadequate contrast filling of the pulmonary vasculature and compared the rate for various IV catheter sizes and locations. In particular, we compared 20-gauge or larger IV catheters in the antecubital fossa or forearm to all other sizes and locations.

Results

A total of 19.3% of the 1500 CTPA reports reviewed met our criteria as suboptimal, and 51.6% of those were due to inadequate filling. Patients with a 20-gauge IV catheter or larger placed in the antecubital fossa or forearm had inadequate filling 9.2% of the time compared to 13.2% for patients who had smaller IVs or IVs in other locations (difference: 4.0% [95% confidence interval, −1.7%–9.7%]). There were also no statistically significant differences in the rates of inadequate filling when data were further stratified by IV catheter location and size.

Conclusion

We did not detect any statistically significant differences in the rate of inadequate contrast filling based on IV catheter locations or sizes. While small differences not detected in this study may exist, it seems prudent to proceed with CTPA in patients with difficult IV access who need emergent imaging even if they have a small or distally located IV.

Telomerase regulation by the long non-coding RNA H19 in human acute promyelocytic leukemia cells

Background

Since tumor growth requires reactivation of telomerase (hTERT), this enzyme is a challenging target for drug development. Therefore, it is of great interest to identify telomerase expression and activity regulators. Retinoids are well-known inducers of granulocytic maturation associated with hTERT repression in acute promyelocytic leukemia (APL) blasts. In a maturation-resistant APL cell line, we have previously identified a new pathway of retinoid-induced hTERT transcriptional repression independent of differentiation. Furthermore, we reported the isolation of a cell variant resistant to this repression. Those cell lines could serve as unique tools to identify new telomerase regulators.

Methods

Using a microarray approach we identified the long non-coding RNA, H19 as a potential candidate playing a role in telomerase regulation. Expression of H19, hTERT, and hTR were examined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Telomerase activity was quantified by quantitative telomeric repeats amplification protocol (qTRAP). In vitro and in vivo assays were performed to investigate H19 function on telomerase expression and activity.

Results

We showed both in retinoid-treated cell lines and in APL patient cells an inverse relationship between the expression of H19 and the expression and activity of hTERT. Exploring the mechanistic link between H19 and hTERT regulation, we showed that H19 is able to impede telomerase function by disruption of the hTERT-hTR interaction.

Conclusions

This study identifies a new way of telomerase regulation through H19’s involvement and thereby reveals a new function for this long non-coding RNA that can be targeted for therapeutic purpose.

Electronic supplementary material

The online version of this article (10.1186/s12943-018-0835-8) contains supplementary material, which is available to authorized users.

Clinical prediction rules for mortality in patients with pulmonary embolism and cancer to guide outpatient management: a meta-analysis

Essentials Clinical prediction rules (CPRs) can stratify patients with pulmonary embolism (PE) and cancer. A meta-analysis was done to assess prognostic accuracy in CPRs for mortality in these patients. Eight studies evaluating ten CPRs were included in this study. CPRs should continue to be used with other patient factors for mortality risk stratification.

SUMMARY

Background Cancer treatment is commonly complicated by pulmonary embolism (PE), which remains a leading cause of morbidity and mortality in these patients. Some guidelines recommend the use of clinical prediction rules (CPRs) to help clinicians identify patients at low risk of mortality and therefore guide care. Objective To determine and compare the accuracy of available CPRs for identifying cancer patients with PE at low risk of mortality. Methods A literature search of Medline and Scopus (January 2000 to August 2017) was performed. Studies deriving/validating ≥ 1 CPR for early post-PE all-cause mortality were included. A bivariate, random-effects model was used to pool sensitivity and specificity estimates for each CPR. Traditional random-effects meta-analysis was performed to estimate the weighted proportion of patients deemed at low risk of early mortality, mortality in low risk patients and odds ratios for death compared with higher-risk patients. Results Eight studies evaluating 10 CPRs were included. The highest sensitivities were observed with Hestia (98.1%, 95% confidence interval [CI] = 75.6-99.9%) and the EPIPHANY index (97.4%, 95% CI = 93.2-99.0%); sensitivities of remaining rules ranged from 59.9 to 96.6%. Of the six CPRs with sensitivities ≥ 95%, none had specificities > 33%. Random-effects meta-analysis suggested that 6.6-51.6% of cancer patients with PE were at low risk of mortality, 0-14.3% of low-risk patients died and low-risk patients had a 43-94% lower odds of death compared with those at higher risk. Conclusions Because of the limited total body of evidence regarding CPRs, their results, in conjunction with other pertinent patient-specific clinical factors, should continue to be used in identifying appropriate management for PE in patients with cancer.

C5a Increases the Injury to Primary Neurons Elicited by Fibrillar Amyloid Beta

C5aR1, the proinflammatory receptor for C5a, is expressed in the central nervous system on microglia, endothelial cells, and neurons. Previous work demonstrated that the C5aR1 antagonist, PMX205, decreased amyloid pathology and suppressed cognitive deficits in two Alzheimer's Disease (AD) mouse models. However, the cellular mechanisms of this protection have not been definitively demonstrated. Here, primary cultured mouse neurons treated with exogenous C5a show reproducible loss of MAP-2 staining in a dose-dependent manner within 24 hr of treatment, indicative of injury to neurons. This injury is prevented by the C5aR1 antagonist PMX53, a close analog of PMX205. Furthermore, primary neurons derived from C5aR1 null mice exhibited no MAP-2 loss after exposure to the highest concentration of C5a tested. Primary mouse neurons treated with both 100 nM C5a and 5 µM fibrillar amyloid beta (fAβ), to model what occurs in the AD brain, showed increased MAP-2 loss relative to either C5a or fAβ alone. Blocking C5aR1 with PMX53 (100 nM) blocked the loss of MAP2 in these primary neurons to the level seen with fAβ alone. Similar experiments with primary neurons derived from C5aR1 null mice showed a loss of MAP-2 due to fAβ treatment. However, the addition of C5a to the cultures did not enhance the loss of MAP-2 and the addition of PMX53 to the cultures did not change the MAP-2 loss in response to fAβ. Thus, at least part of the beneficial effects of C5aR1 antagonist in AD mouse models may be due to protection of neurons from the toxic effects of C5a.

Reduction in surgical fog with a warm humidified gas management protocol significantly shortens procedure time in pediatric robot-assisted laparoscopic procedures

INTRODUCTION

The adoption of robot-assisted laparoscopic (RAL) procedures in the field of urology has occurred rapidly, but is, to date, without pediatric-specific instrumentation. Surgical fog is a significant barrier to safe and efficient laparoscopy. This appears to be a significant challenge when adapting three-dimensional 8.5-mm scopes to use in pediatric RAL surgery. The objective of the present study was to compare matched controls from a prospectively collected database to procedures that were performed utilizing special equipment and a protocol to minimize surgical fog in pediatric RAL procedures.

METHODS

A prospectively collected database of all patients who underwent RAL pediatric urology procedures was used to compare: procedure, age, sex, American Society of Anesthesiologists score, weight, console time, number of times the camera was removed to clean the lens during a procedure, length of hospital stay, and morphine equivalents required in the postoperative period. A uniquely developed protocol was used, it consisted of humidified (95% relative humidity) and warmed CO₂ gas (95 °F) insufflation via Insuflow® on a working trocar, with active smoke evacuation via PneuVIEW®XE on the opposite working trocar with a gas pass through of 3.5-5 l/min. The outcomes were compared with matched controls (Summary Fig).

RESULTS

The novel gas protocol was utilized in 13 procedures (five pyeloplasties, two revision pyeloplasties, three ureteroureterostomies (UU), three nephrectomies) and compared with 13 procedures (six pyeloplasties, one revision pyeloplasty, three UU, three nephrectomies) prior to the protocol development. There was no statistical difference in age (P = 0.78), sex (P = 0.11), ASA score (P = 1.00) or weight (P = 0.69). There were no open conversions, ≥Grade 2 Clavien complications, or readmissions within 30 days in either group.

CONCLUSIONS

This novel gas protocol yielded a statistically significant reduction in procedure time, by decreasing the number of times the camera was required to be pulled during the case by more than five occurrences, and saved approximately 35 min on average per case.

Malignant Gastric Outlet Obstruction from Pancreatic Cancer

Patients with advanced-stage pancreatic cancer are typically burdened by many symptoms that impair functioning and worsen quality of life. We report an exceptional case of a 73-year-old woman with T4N1M0 adenocarcinoma of the uncinate process of the pancreas who developed significant gastric outlet obstruction – an uncommon yet potentially life-threatening complication of disease progression. She developed progressive abdominal pain and emesis, and profound dilatation of her stomach was detected on a radiation therapy simulation CT scan that required urgent decompression. Malignant gastric outlet obstruction must be included in the differential diagnosis when patients with known advanced disease of the pancreas present with obstructive upper gastrointestinal symptoms.

The impact of appointment-based medication synchronization on medication taking behaviour and health outcomes: A systematic review

WHAT IS KNOWN AND OBJECTIVE

Proactive synchronization of medication refills through an appointment-based model (ABM) is a community pharmacy-based intervention targeting adherence to medications. We aimed to systematically review evidence on the impact of the ABM on medication taking behaviour, health resource utilization, clinical outcomes and the preferences of patients and providers.

METHODS

We conducted a systematic literature search of MEDLINE and Scopus from database inception through 6 February 2017. Studies were included if they were original investigations evaluating the impact of the ABM on at least one outcome of interest and published in the peer-reviewed literature as a full-text manuscript in the English language. Outcomes included medication taking behaviour, clinical and economic outcomes, health resource utilization, and patient or provider satisfaction. Data were synthesized qualitatively.

RESULTS

Five studies, mostly observational in design and with low risk of bias, were included. Objective measures of medication taking behaviour were consistently improved in patients enrolled in an ABM vs control, indicating an association between appointment-based medication synchronization with improved adherence and decreased likelihood of non-persistence. A single decision analysis indicates a cost savings over 1 year associated with the appointment-based medication synchronization programme modelled, for hypertension, diabetes and hyperlipidaemia. Limited data regarding health resource utilization and clinical outcomes and patient or provider satisfaction exist and are currently inconclusive.

WHAT IS NEW AND CONCLUSION

The ABM provides a unique, patient-centred service to improve medication adherence amongst patients taking chronic medications while demonstrating a positive financial return on investment. Future research is needed to determine the impact of the ABM on final health outcomes.

The influence of intramolecular sulfur-lone pair interactions on small-molecule drug design and receptor binding

Sulfur-lone pair interactions are important conformational control elements in sulfur-containing heterocycles that abound in pharmaceuticals, natural products, agrochemicals, polymers and other important classes of organic molecules. Nonetheless, the role of intramolecular sulfur-lone pair interactions in the binding of small molecules to receptors is often overlooked. Here we analyze the magnitudes and origins of these interactions for a variety of biologically relevant small molecules using quantum chemical and automated docking calculations. In most cases examined in this study, the lowest energy conformation of the small molecule displays a sulfur-lone pair close contact. However, docking studies, both published and new, often predict that conformations without sulfur-lone pair contacts have the best binding affinity for their respective receptors. This is a serious problem. Since many of these predicted bound conformations are not actually energetically accessible, pursuing design (e.g., drug design) around these binding modes necessarily will lead, serendipity aside, to dead end designs. Our results constitute a caution that one best not neglect these interactions when predicting the binding affinities of potential ligands (drugs or not) for hosts (enzymes, receptors, DNA, RNA, synthetic hosts). Moreover, a better understanding and awareness of sulfur-lone pair interactions should facilitate the rational modulation of host-guest interactions involving sulfur-containing molecules.

Three-Dimensional Printing in Orthopedic Surgery

Three-dimensional (3D) printing is emerging as a clinically promising technology for rapid prototyping of surgically implantable products. With this commercially available technology, computed tomography or magnetic resonance images can be used to create graspable objects from 3D reconstructed images. Models can enhance patients' understanding of their pathology and surgeon preoperative planning. Customized implants and casts can be made to match an individual's anatomy. This review outlines 3D printing, its current applications in orthopedics, and promising future directions.

WT1 expression is inversely correlated with MYCN amplification or expression and associated with poor survival in non-MYCN-amplified neuroblastoma

Neuroblastoma (NB) is the most common extra cranial solid tumor in childhood and the most frequently diagnosed neoplasm during infancy. A striking feature of this tumor is its clinical heterogeneity. Several tumor progression markers have been delineated so far, among which MYCN amplification, which occurs in about 25% of total NB cases, with the percentage increasing to 30% in advanced stage NB. Although MYCN amplification is strongly correlated with NB of poor outcome, the MYCN status cannot alone predict all cases of poor survival in NB. Indeed NB without MYCN amplification (about 70-80% of NB) are not always favorable. WT1 was initially identified as a tumor suppressor gene involved in the development of a pediatric renal tumor (Wilms' tumor). Here, we describe an inverse correlation between WT1 expression and MYCN amplification and expression. However and most notably, our results show that WT1 gene expression is associated with a poor outcome for patients showing non-MYCN-amplified tumors. Thus WT1 expression is clinically significant in NB and may be a prognostic marker for better risk stratification and for an optimized therapeutic management of NB.