Spontaneous activity in peripheral sensory nerves: a systematic review

ABSTRACT

In the peripheral nervous system, spontaneous activity in sensory neurons is considered to be one of the 2 main drivers of chronic pain states, alongside neuronal sensitization. Despite this, the precise nature and timing of this spontaneous activity in neuropathic pain is not well-established. Here, we have performed a systematic search and data extraction of existing electrophysiological literature to shed light on which fibre types have been shown to maintain spontaneous activity and over what time frame. We examined both in vivo recordings of preclinical models of neuropathic pain, as well as microneurography recordings in humans. Our analyses reveal that there is broad agreement on the presence of spontaneous activity in neuropathic pain conditions, even months after injury or years after onset of neuropathic symptoms in humans. However, because of the highly specialised nature of the electrophysiological methods used to measure spontaneous activity, there is also a high degree of variability and uncertainty around these results. Specifically, there are very few directly controlled experiments, with less directly comparable data between human and animals. Given that spontaneous peripheral neuron activity is considered to be a key mechanistic feature of chronic pain conditions, it may be beneficial to conduct further experiments in this space.

Comparative Efficacy of Subcutaneous and Intravenous Infliximab and Vedolizumab for Maintenance Treatment of TNF-naive Adult Patients with Inflammatory Bowel Disease: A Systematic Literature Review and Network Meta-analysis

BACKGROUND

Infliximab and vedolizumab are widely used to treat Crohn's disease (CD) and ulcerative colitis (UC).

AIMS

This systematic review and network meta-analysis evaluated comparative efficacy of various regimens for intravenous or subcutaneous infliximab and vedolizumab during maintenance treatment in CD and UC.

METHODS

Parallel-group randomized controlled trials (RCTs) were identified by a systematic literature review (CRD42022383401) and included if they evaluated therapeutics of interest for maintenance treatment of adults with moderate-to-severe luminal CD or UC and assessed clinical remission between Weeks 30 and 60. Clinical remission rates in CD or UC and mucosal healing rates in UC were analyzed in a Bayesian network meta-analysis model. Endoscopic outcomes in CD were synthesized by proportional meta-analysis.

RESULTS

Overall, 13 RCTs were included in the analyses. All vedolizumab studies randomized induction responders to maintenance treatment; infliximab studies used a treat-through design. Subcutaneous infliximab 120 mg every 2 weeks had the highest odds ratio (OR) [95% credible interval] versus placebo for clinical remission during the maintenance phase (CD: 5.90 [1.90-18.2]; UC: 5.45 [1.94-15.3]), with surface under the cumulative ranking curve (SUCRA) values of 0.91 and 0.82, respectively. For mucosal healing in UC, subcutaneous infliximab 120 mg every 2 weeks showed the highest OR (4.90 [1.63-14.1]), with SUCRA value of 0.73, followed by intravenous vedolizumab 300 mg every 4 weeks (SUCRA value, 0.70). Endoscopic outcomes in CD were better with subcutaneous infliximab 120 mg every 2 weeks than intravenous infliximab 5 mg/kg every 8 weeks.

CONCLUSIONS

Subcutaneous infliximab showed a favorable efficacy profile for achieving clinical remission and endoscopic outcomes during maintenance treatment in CD or UC.

CT findings of inferior vena cava trauma according to the level of injury: a retrospective analysis of 19 cases in a single trauma centre

AIM

To analyse the clinicoradiological characteristics of traumatic inferior vena cava (IVC) injury level on preoperative computed tomography (CT).

MATERIALS AND METHODS

This retrospective study evaluated patients from a single trauma centre treated for traumatic IVC injury between January 2014 and January 2021. Data on demographics, mechanism of injury, Injury Severity Score, radiological findings on CT and angiography, IVC injury level in surgical findings, complications, and clinical outcomes were collected.

RESULTS

During the 8-year study period, 36 patients presented with traumatic IVC injury: 19 underwent preoperative CT with 17 (89%) blunt and two (11%) penetrating injuries. The most common primary CT sign was contour abnormality (53%, n=10), followed by intraluminal flap and active extravasation (21%, n=4). Among the secondary signs, hepatic laceration (53%, n=10) and retroperitoneal haemorrhage (53%, n=10) were the most common. Frequencies of primary and secondary signs were higher in the infrarenal and suprarenal than in the retrohepatic vena cava injuries. Diagnostic capability of preoperative CT for IVC injury differed according to the IVC level. The detection rate was the highest for an infrarenal vena cava injury at 100% (n=4), followed by that for a suprarenal, suprahepatic, and retrohepatic vena cava injuries at 75% (n=3), 43% (n=3), and 25% (n=1), respectively.

CONCLUSION

CT findings of traumatic IVC injuries may vary depending on the mechanism and anatomical site of injury. Familiarity with IVC injury imaging features may help in diagnosis and surgical treatment planning.

Suspected human intravenous immunoglobulin-induced acute haemolytic anaemia in a dog

A 2-year-old mixed breed dog presented with a 1-year history of crust and erosion on the nasal planum. Because histopathological examination revealed ruptured intraepidermal pustules and superficial dermal inflammation, the dog was diagnosed with pemphigus foliaceus. Human intravenous immunoglobulin was administered in two consecutive doses of 0.5 g/kg/day due to poor therapeutic response to previous immunosuppressive therapy. From Day 3 after the first dose of human intravenous immunoglobulin, tachypnoea, pale mucous membrane, haemoglobinuria and haemoglobinemia were observed, thus confirming haemolytic anaemia. Other drug-induced haemolytic anaemias were excluded because no additional drugs had been administered before the haemolysis occurred. Immune-mediated haemolytic anaemia was also excluded because the direct antiglobulin test was negative. Two transfusions were performed, and haemolysis was not observed from Day 4 of haemolytic anaemia onset. In conclusion, human intravenous immunoglobulin-induced haemolytic anaemia should be considered in dogs that develop haemolysis following the administration of human intravenous immunoglobulin.

Onyiuke Grading Scale: A clinical classification system for the diagnosis and management of Bertolotti syndrome

BACKGROUND

Lumbosacral transitional vertebrae (LSTV) is a common anatomic variant of the spine, characterized by the formation of a pseudoarticulation between the transverse process of the lumbar vertebrae and sacrum or ilium. LSTVs have been implicated as a potential source of low back pain - dubbed Bertolotti syndrome. Traditionally, LSTVs have only been subdivided into types I-IV based on the Castellvi radiographic classification system.

OBJECTIVE

Solely identifying the type of LSTV radiographically provides no clinical relevance to the treatment of Bertolotti syndrome. Here, we seek to analyze such patients and identify a clinical grading scale and diagnostic-therapeutic algorithm to optimize care for patients with this congenital anomaly.

METHODS

Patients presenting with back pain between 2011 and 2018 attributable to a lumbosacral transitional vertebra were identified retrospectively. Data was collected from these patients' charts regarding demographic information, clinical presentation, diagnostic imaging, treatment and outcomes. Based on evaluation of these cases and review of the literature, a diagnostic-therapeutic algorithm is proposed.

RESULTS

Based on our experiences evaluating and treating these patients and review of the existing literature, we propose a clinical classification system for Bertolotti syndrome: we proposed a 4-grade scale for patients with Bertolotti syndrome based upon location, severity, and characteristics of pain experienced due to LSTVs.

CONCLUSION

Based on our experience with the cases illustrated here, we recommend managing patients with LSTV based on our diagnostic-therapeutic algorithm. Moving forward, a larger prospective study with a larger patient cohort is needed to further validate the treatment paradigm.

Root Coverage Predictability in the Treatment of Gingival Recessions on Mandibular Anterior Teeth

INTRODUCTION

Mandibular anterior teeth are most frequently affected by gingival recession. However, data regarding mucogingival treatment aimed at root coverage in this specific location are limited.

OBJECTIVE

The purpose of this study was to systematically review the scientific literature and to use the meta-analytic approach to address the following focused question: "What is the effectiveness of different surgical approaches on clinical and patient-related outcomes in the treatment of buccal gingival recessions on mandibular anterior teeth?"

METHODS

Studies were located by searching 3 electronic databases (Medline, Scopus, and Cochrane databases) and cross-referencing. Randomized and nonrandomized studies including at least 1 arm involving the use of pedicle flaps and/or free soft tissue grafts in the treatment of gingival recessions (recession type [RT] 1 and RT2) located on the buccal aspects of mandibular centrals, laterals and canines, were included in the analysis. Primary outcome was mean root coverage (mRC), expressed in percentage, based on a 3- to 12-mo follow-up observation. A Bayesian single-arm network meta-analysis was performed to identify a treatment hierarchy of the different surgical techniques.

RESULTS

Sixteen studies, with a total of 23 arms, were included in the quantitative analysis. The greatest mRC is associated with laterally positioned flap (LPF) + connective tissue graft (CTG) (91.2%) and tunnel (TUN) + CTG (89.4%), whereas LPF alone, coronally advanced flap (CAF) + CTG, and free gingival graft (FGG) showed lower mRC (79.1%, 78.9%, and 68.5% respectively). TUN + CTG provides significantly greater mRC compared to CAF+CTG. No difference among the procedures could be observed in terms of keratinized tissue width gain.

CONCLUSIONS

Treatment hierarchy generated by an arm-based network meta-analysis model suggested that tunnel and laterally positioned flap, both in combination with connective tissue graft, may provide the greatest mean root coverage in the treatment of mandibular anterior recessions.

KNOWLEDGE TRANSFER STATEMENT

The results of the present systematic review can be used by clinicians when deciding which approach to adopt when treating buccal gingival recessions on mandibular anterior teeth. In particular, procedures based on a laterally positioned flap or a tunneling technique, both in combination with connective tissue graft, seem to be the most predictable therapeutic decision.

Risk factors and outcomes of immune and non-immune causes of diffuse alveolar hemorrhage: a tertiary-care academic single-center experience

Diffuse alveolar hemorrhage (DAH) is a rare but potentially life-threatening emergency that has both immune and non-immune etiologies. The objective of this investigation was to compare the risk factors and outcomes of immune and non-immune causes of DAH at a tertiary-care academic center. This was a retrospective observational study conducted at a University center. We reviewed all chest radiographs spanning 12 years (2007-2019) at our institute with the words "diffuse alveolar hemorrhage" in the body of their report, and ascertained cases of DAH through a detailed chart review. We used Chi-squared test to determine the differences in risk factors and outcomes between immune versus non-immune causes of DAH. We performed logistic regressions to assess whether baseline demographics and clinical features influence four critical outcomes: death, shock, renal failure, and severe anemia requiring transfusions. Over the 12-year period, there were 88 patients with DAH, 55 with non-immune and 33 with immune etiologies. Among immune causes of DAH, granulomatosis with polyangiitis (GPA) (10.2%), microscopic polyangiitis (MPA) (9%) and systemic lupus erythematosus (SLE) (9%) were most common. Among non-immune causes of DAH, coagulopathy (6.8%), decompensated heart failure (4.5%) and infection (3.4%) were most common. Patients with non-immune causes of DAH were 45.8% more likely to die and 20.7% less likely to experience sustained remission (p = 0.001). Patient with immune causes of DAH were 21% more likely to have extra-pulmonary findings and 23.7% more likely to have received hemodialysis (HD). The presence of extra-pulmonary findings was statistically significantly correlated with the number of blood products received, the need for HD and non-statistically significantly correlated with likelihood of death. Patients with immune causes of DAH were 71.5% more likely to receive multimodal therapy including corticosteroids. Immune-mediated DAH is associated with a better prognosis than non-immune DAH, despite its greater association with extra-pulmonary findings and requirement for hemodialysis.

Retroductal Delivery of Epidermal Growth Factor Protects Salivary Progenitors after Irradiation

Salivary gland hypofunction after irradiation is associated with a deficit of epithelial stem/progenitors in salivary glands. Although epidermal growth factor (EGF) is known to stimulate the proliferation of epithelial cells, the therapeutic effect of EGF on salivary epithelial stem/progenitors remains undetermined. In this study, we administered EGF to submandibular glands (SMGs) via a retrograde route through the SMG excretory duct before fractionated irradiation and examined whether EGF could protect salivary epithelial progenitor cells from radiation and alleviate radiation-induced salivary hypofunction. EGF-treated mice exhibited greater body and gland weights at 12 wk after irradiation than untreated mice. The retroductal delivery of EGF improved salivary secretory function and increased salivary amylase activity in a dose-dependent manner. Histological examinations highlighted the amelioration of the loss of keratine-14⁺ (KRT14⁺) basal ductal and/or MIST1⁺ acinar cells, as well as induction of fibrosis, following irradiation in EGF-treated mice. An additional in vitro experiment using a salivary gland organoid irradiation model indicated that the radioprotective effects of EGF promoted the growth and inhibited the apoptotic cell death of salivary epithelial cells. Our results suggest that retroductal delivery of EGF may be a promising therapeutic option for preventing radiation-induced salivary gland hypofunction.

MRI Features May Predict Molecular Features of Glioblastoma in Isocitrate Dehydrogenase Wild-Type Lower-Grade Gliomas

BACKGROUND AND PURPOSE

Isocitrate dehydrogenase (IDH) wild-type lower-grade gliomas (histologic grades II and III) with epidermal growth factor receptor (EGFR) amplification or telomerase reverse transcriptase (TERT) promoter mutation are reported to behave similar to glioblastoma. We aimed to evaluate whether MR imaging features could identify a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

MATERIALS AND METHODS

In this multi-institutional retrospective study, pathologically confirmed IDH wild-type lower-grade gliomas from 2 tertiary institutions and The Cancer Genome Atlas constituted the training set (institution 1 and The Cancer Genome Atlas, 64 patients) and the independent test set (institution 2, 57 patients). Preoperative MRIs were analyzed using the Visually AcceSAble Rembrandt Images and radiomics. The molecular glioblastoma status was determined on the basis of the presence of EGFR amplification and TERT promoter mutation. Molecular glioblastoma was present in 73.4% and 56.1% in the training and test sets, respectively. Models using clinical, Visually AcceSAble Rembrandt Images, and radiomic features were built to predict the molecular glioblastoma status in the training set; then they were validated in the test set.

RESULTS

In the test set, a model using both Visually AcceSAble Rembrandt Images and radiomic features showed superior predictive performance (area under the curve = 0.854) than that with only clinical features or Visually AcceSAble Rembrandt Images (areas under the curve = 0.514 and 0.648, respectively; P < . 001, both). When both Visually AcceSAble Rembrandt Images and radiomics were added to clinical features, the predictive performance significantly increased (areas under the curve = 0.514 versus 0.863, P < .001).

CONCLUSIONS

MR imaging features integrated with machine learning classifiers may predict a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

Coronary angiographic manifestations of fibromuscular dysplasia and clinical outcomes in patients with spontaneous coronary artery dissection

Background

Fibromuscular dysplasia (FMD) is a common predisposing condition for spontaneous coronary artery dissection (SCAD), which is an important cause of myocardial infarction (MI) in young to middle-aged women. However, its impact on clinical presentation, coronary anatomies, and outcomes have not been reported.

Purpose

To evaluate coronary angiographic characteristics and clinical outcomes in SCAD patients with or without underlying extracoronary FMD.

Methods

We retrospectively analyzed patients enrolled in our Vancouver SCAD registries who were screened for extracoronary FMD. Extracoronary FMD was defined as the presence of multifocal FMD on catheter or noninvasive angiography (computed tomographic or magnetic resonance imaging) in ≥1 extracoronary vascular beds. We reviewed coronary angiograms for manifestations of coronary FMD that were previously described (i.e. irregular stenosis, smooth stenosis, dilatation/ectasia, and tortuosity). Severe tortuosity was defined as ≥2 consecutive bends ≥180° at any cardiac cycle or 360° loop in ≥1 epicardial artery that was ≥2 mm in diameter. Clinical outcomes of major adverse cardiovascular event (MACE), a composite of all-cause death, MI, and stroke, were evaluated.

Results

We included 346 SCAD patients, 250 (72.3%) had extracoronary FMD. Patients with FMD were older (54.6±9.5 vs. 51.7±9.8 years) and more likely to have prior history of MI (7.2% vs. 1.0%, p=0.047) and stroke (4.4% vs. 0%, p=0.081) compared with non-FMD patients. The proportion of multivessel SCAD and TIMI flow was not different between groups, but type 3 SCAD was more commonly observed in FMD group (11.6% vs. 3.1%, p=0.026). On coronary angiography, severe tortuosity was more prevalent in patients with extracoronary FMD (58.4% vs. 36.5%, p&lt;0.001), whereas rates of irregular stenosis, smooth stenosis, and dilatation/ectasia were not significantly different (Figure). Percutaneous coronary intervention was performed in 13.2% of FMD and 15.6% of non-FMD group, with similar success rates (75.8% vs. 69.2%, p=0.65). In-hospital and long-term MACE rate at median follow-up of 1032 (IQR 453–1096) days were not different between FMD and non-FMD groups (in-hospital: 5.6% vs. 8.3%, p=0.492; long-term: 19.6% vs. 15.6%, p=0.185).

Conclusion

In SCAD patients, severe coronary tortuosity was more prevalent in patients with FMD than those without. Despite the complex coronary anatomy, FMD was not associated with worse outcomes.

Differences in coronary manifestations

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Canadian Institutes of Health Research

Machine learning for predicting fractional flow reserve based on optical coherence tomography in intermediate coronary stenosis

Background

Machine learning approaches using intravascular optical coherence tomography (OCT) to predict fractional flow reserve (FFR) have not been previously investigated. The objective of the study was to evaluate a machine learning method to estimate FFR based on intravascular OCT images in intermediate coronary lesions.

Methods

Data from both OCT- and wire-based FFR methods were obtained for lesions of the left anterior descending artery in 125 patients. Based on the total number of lesions, training and testing groups were partitioned at a ratio of 5:1. For the training group, 36 features, including 16 clinical and lesion characteristics, and 21 OCT features, were used to model machine learning-FFR. machine learning-FFR values were then derived for the testing group and compared with wire-based FFR values in terms of a diagnosis of ischemia (FFR &lt;0.8).

Results

Clinical and lesion characteristics and OCT features between the training and testing groups were similar. During the machine learning modeling of the training group, six important features of machine learning-FFR were identified: minimal luminal area, percentage of the stenotic area, lesion length, proximal luminal area, pre-procedural platelet count, and hypertension. machine learning-FFR values showed a good correlation (r=0.853, P&lt;0.001) with wire-based FFR values (Figure 1A). The diagnostic power of an FFR value less than 0.8, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of machine learning-FFR values for the testing group were 85.7%, 100%, 100%, 77.8%, and 90.5%, respectively (Figure 1B). Additionally, OCT-based machine learning-FFR values showed a good diagnostic accuracy compared with other image-based FFR values.

Conclusions

The OCT-based machine learning-FFR method can be used to simultaneously acquire information on both image and functional modalities using one invasive procedure, suggesting that it may be used to optimize treatments for intermediate coronary artery stenosis, as well as save time and cost.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Funded by the Korean government (MSIT) (no. 2017R1A2B2003191)

TEK is a novel prognostic marker for clear cell renal cell carcinoma

OBJECTIVE

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer. However, effective therapeutics for ccRCC are lacking. Novel biomarkers could provide critical information when determining prognoses for patients with ccRCC. In this study, we sought to determine if the expression of receptor tyrosine kinase (TEK) could be a potential novel prognostic biomarker for ccRCC. TEK, originally identified as an endothelial cell-specific receptor, plays an important role in the modulation of vasculogenesis and remodeling. Altered TEK expression has been observed in tumor tissues (e.g., oral squamous cell carcinomas, leukemia) and breast, gastric and thyroid cancers. However, the role of TEK in ccRCC remains unknown.

PATIENTS AND METHODS

Differential TEK expression between non-metastatic (stage M0) and metastatic (stage M1) ccRCC patient cohorts was determined from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Furthermore, TEK expression was assessed as a prognostic factor using the time-dependent area under the curve (AUC) of Uno's C-index, the AUC value of the receiver operating characteristics (ROC) at 5 years, Kaplan-Meier survival curves and multivariate analyses.

RESULTS

A Kaplan-Meier curve analysis revealed that the downregulation of TEK expression was associated with a poor prognosis for patients with ccRCC with good discrimination (p<0.0001 and p=0.0044 for the TGCA and ICGC cohorts, respectively). Analyses of C-indices and receiver operating characteristic AUC values further support this discriminative ability. Moreover, multivariate analyses showed the prognostic significance of TEK expression levels (p<0.001).

CONCLUSIONS

Although additional clinical investigations will be needed, our results suggest that TEK is a potential biomarker for ccRCC.

Magnesium-Dependent Promotion of H2O2 Production Increases Ecological Competitiveness of Oral Commensal Streptococci

The pyruvate oxidase (SpxB)-dependent production of H₂O₂ is widely distributed among oral commensal streptococci. Several studies confirmed the ability of H₂O₂ to antagonize susceptible oral bacterial species, including caries-associated Streptococcus mutans as well as several periodontal pathobionts. Here we report a potential mechanism to bolster oral commensal streptococcal H₂O₂ production by magnesium (Mg²⁺) supplementation. Magnesium is a cofactor for SpxB catalytic activity, and supplementation increases the production of H₂O₂ in vitro. We demonstrate that Mg²⁺ affects spxB transcription and SpxB abundance in Streptococcus sanguinis and Streptococcus gordonii. The competitiveness of low-passage commensal streptococcal clinical isolates is positively influenced in antagonism assays against S. mutans. In growth conditions normally selective for S. mutans, Mg²⁺ supplementation is able to increase the abundance of S. sanguinis in dual-species biofilms. Using an in vivo biophotonic imaging platform, we further demonstrate that dietary Mg²⁺ supplementation significantly improves S. gordonii oral colonization in mice. In summary, our results support a role for Mg²⁺ supplementation as a potential prebiotic to promote establishment of oral health-associated commensal streptococci.

SAT0247 PREDICTORS OF ADVERSE OUTCOMES IN DIFFUSE ALVEOLAR HEMORRHAGE OF IMMUNE AND NON-IMMUNE CAUSES: 12-YEAR EXPERIENCE FROM A UNIVERSITY HOSPITAL

Background:

Diffuse alveolar hemorrhage (DAH) is a rare, life-threatening condition that has either immune or non-immune etiologies1. DAH caused by capillaritis can be immune-mediated (IM-DAH), e.g. anti-neutrophil cytoplasmic antibody (ANCA) vasculitis and systemic lupus erythematosus, but DAH may also result from anticoagulation, heart failure, drugs or inhaled toxins. Since IM-DAH has specific therapies available, we hypothesized that patients with IM-DAH would have a better prognosis.

Objectives:

We did a retrospective analysis of all DAH cases seen at our university hospital in the last 12 years to investigate the predictors of adverse outcomes.

Methods:

Using Epic radiant and Agfa Radiology Information System databases, we queried electronic medical records of all patients admitted to our university between Jan 2007 to Jan 2019 who had the words “diffuse alveolar hemorrhage” in their chest x-ray report. We manually reviewed charts of all these patients to confirm true DAH. True DAH was defined as suspicion of DAH on chest x-ray plus inclusion of DAH on the discharge problem list. We did a detailed chart review of true DAH cases to extract information regarding demographics, baseline disease characteristics, physical/serology/imaging findings, treatment received, and outcomes. The outcomes of interest were death, intubation, shock, need for hemodialysis (HD), and red blood cell transfusions. We compared IM-DAH with non IM-DAH cases using descriptive statistics, t-test, and chi-squared tests. We used logistic regression models to assess the influence of baseline characteristics on outcomes. A p-value < 0.05 was considered statistically significant.

Results:

There were 88 cases of DAH (M:F 54:34, median age 57) fulfilling inclusion criteria (Table 1). The non-immune etiology was diagnosed in 63%, while 36% were IM-DAH (18% ANCA associated, 9% SLE, 2% decompensated heart failure, the rest were others). No clear etiology for DAH was found in 37.5% cases. Death within 90 days of onset of DAH occurred in 37.5%, 5.6% had recurrent DAH, and 56.8% had sustained remission. Non-IM DAH cases had worse outcomes such as death and were less likely to experience sustained remission (Chi-squared = 19.1, p < 0.001), though IM-DAH were more likely to receive HD (Chi-squared = 7.5, p-value 0.01). Presence of extrapulmonary findings (e.g. nephritis) was a risk factor for adverse outcome, and was statistically significantly correlated with the amount of blood products received, need for HD and likelihood of death, which did not reach statistical significance. Shock and intubation were associated with a higher likelihood of death (p = 0.02 and p = 0.001, respectively).

Table 1.

Comparison of Clinical Characteristics of Immune versus Non-Immune Cases of Diffuse Alveolar Hemorrhage

VariableImmune cases(N = 32)Non-immune cases(N = 56)Statistical comparisonAge (years)51.0955.91P = 0.196%Female43.835.7P = 0.510%presenting with hemoptysis8 (25%)14 (25%)P = 0.101%extrapulmonary findings20 (62.5%)1 (1.7%)P = 6.9*e-10pANCA positive16 (50%)2 (3.6%)P = 0.0004% on anticoagulation9.42.5P = 0.090Mean Creatinine2.381.89P = 0.507Mean hospital length of stay (days)16.6923.27P = 0.139Drop in Hemoglobin prior to DAH and day of DAH0.241.17P = 0.070%Bronchoscopy-confirmed DAH62.575.0P = 0694Mean units of blood transfused1.912.66P = 0.448%Need for hemodialysis37.512.5P = 0.010%Shock (any kind)21.932.1P = 0.338%Need for intubation43.862.5P = 0.122%Death within 90 days12.552.7P = 0.0009

Conclusion:

DAH, a life-threatening condition, has both immune and non-immune etiologies. Our 12-years, single-center, university hospital experience showed that IM-DAH has a better prognosis than non IM-DAH. Presence of extrapulmonary manifestations was associated with worse outcomes.

References:

[1]Moo Suk Park. Diffuse Alveolar Hemorrhage. Tuberc Respir Dis (Seoul). 2013 Apr; 74(4): 151–162.

[2]Nasser M, Cottin V. Alveolar Hemorrhage in Vasculitis (Primary and Secondary). Semin Respir Crit Care Med. 2018 Aug;39(4):482-493.

Disclosure of Interests:

Ambika Bhushan: None declared, Dongseok Choi: None declared, Guy Maresh: None declared, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB

Exposure to oral bisphosphonates and risk of gastrointestinal cancer

Few studies have explored the association of oral bisphosphonate exposure and gastrointestinal cancer within Asian populations. In this study, we investigated 45,397 Korean women from the nationwide population-based cohort from 2002 to 2013. Oral bisphosphonate exposure did not appear to be associated with elevated or reduced risk for gastrointestinal cancer.

INTRODUCTION

While several studies suggested increased risk in upper gastrointestinal (GI) cancer or reduced risk in colorectal cancer upon bisphosphonate exposure, the association is less explored within Asian populations. We investigated the effect of oral bisphosphonate exposure on the risk of GI cancers within a nationwide population-based cohort.

METHODS

This study used two separate cohorts. The first cohort included 45,397 women aged 60 years or older from the National Health Insurance Service-Health Screening Cohort during 2002-2013. Participants were classified into bisphosphonate users and non-users based on drug exposure during 2002-2007, and followed-up from the index date of January 1, 2008. The second cohort included 25,665 newly diagnosed osteoporosis patients who started taking oral bisphosphonate during 2003-2008. After 4 years of drug exposure period, patients were separated into quartiles based on cumulative oral bisphosphonate exposure. Participants were followed-up until December 31, 2013 for GI cancer, stomach cancer, and colorectal cancer. Cox proportional hazard regression models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs) for the cancer risks.

RESULTS

Compared to bisphosphonate non-users, no significant risk difference was observed among bisphosphonate users on GI (HR 1.06; 95% CI 0.87-1.28), stomach (HR 1.11; 95% CI 0.85-1.47) and colorectal cancers (HR 1.04; 95% CI 0.79-1.37). Among bisphosphonate users, increasing doses of bisphosphonate exposure was not associated with elevated or reduced risk for GI cancer (p for trend 0.573).

CONCLUSION

Oral bisphosphonate use did not appear to be associated with elevated or reduced risk for GI cancers.

Spinal Stenosis in Familial Transthyretin Amyloidosis

Here we describe a patient with genetically confirmed ATTR, a family history of the disease and histological confirmation following carpal tunnel release surgery but no other manifestations. The first major neurological or systemic manifestation was cauda equina syndrome with ATTR deposits contributing to lumbar spinal stenosis. Recent gene therapy trials showed improvement in the neuropathy in TTR amyloidosis. This case highlights the need for awareness of the heterogeneous neurological phenotype seen in ATTR to aid earlier diagnosis especially now that disease modifying therapies are available.

P4393Current smoking and gender difference in South Korean AMI patients who underwent PCI with DES

Background

There is some debate on whether or not there is a gender difference is present between current smoking and cardiovascular disease.

Purpose

We decide to evaluate the impact of sex difference on the 2-year clinical outcomes in Korean acute myocardial infarction (AMI) patients who currently smoke and who underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES).

Methods

The data of this study was obtained from the Korea Acute Myocardial Infarction (KAMIR) registry. More than fifty high-volume universites or community hospitals with facilities for primary PCI and onsite cardiac surgery participated in this KAMIR registry. A total of 12565 current smoker AMI patients were enrolled and divided into the male (n=11767, 93.6%) or female (n=798, 6.4%) group. The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), and total repeat revascularization.

Results

Before risk adjustment, the cumulative incidences of MACE (7.2% vs. 10.0%, hazard ratio [HR], 1.419; 95% confidence interval [CI], 1.125–1.790; P=0.003), all-cause death (HR, 1.988; 95% CI, 1.417–2.789; P<0.001), and re-MI (HR, 1.885; 95% CI, 1.154–3.078; P=0.011) were significantly higher in the female group compared with the male group. However, after adjustment the cumulative incidences of MACE (adjusted HR, 1.047; 95% CI, 0.756–1.450; P=0.782), all-cause death, re-MI, total repeat revascularization, TLR, TVR, and non-TVR were similar between the two groups.

Clinical outcomes at 2-year Outcomes Cumulative Events at 2-year (%) Unadjusted Adjusted* Propensity-score adjusted Male Female Log-rank Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value MACE 819 (7.2) 78 (10.0) 0.003 1.419 (1.125–1.790) 0.003 1.047 (0.756–1.450) 0.782 1.133 (0.871–1.473) 0.352 All-cause death 283 (2.5) 38 (4.8) <0.001 1.988 (1.417–2.789) <0.001 0.764 (0.457–1.279) 0.306 1.105 (0.744–1.641) 0.620 Cardiac death 224 (1.9) 25 (3.2) 0.016 1.654 (1.094–2.500) 0.017 0.512 (0.261–1.005) 0.052 0.822 (0.511–1.322) 0.419 Re-MI 142 (1.3) 18 (2.4) 0.010 1.885 (1.154–3.078) 0.011 1.741 (0.887–3.419) 0.107 1.835 (1.109–3.375) 0.062 Total revascularization 444 (4.0) 27 (3.6) 0.594 0.900 (0.610–1.327) 0.594 1.069 (0.654–1.748) 0.789 0.956 (0.627–1.458) 0.835 TLR 121 (1.1) 8 (1.1) 0.956 0.980 (0.479–2.004) 0.956 0.955 (0.366–2.497) 0.926 0.868 (0.395–1.910) 0.726 TVR 228 (2.1) 14 (1.9) 0.726 0.908 (0.529–1.558) 0.726 1.051 (0.518–2.135) 0.890 0.935 (0.519–1.684) 0.823 Non-TVR 223 (2.0) 13 (1.7) 0.602 0.862 (0.493–1.508) 0.602 1.060 (0.536–2.097) 0.867 0.942 (0.514–1.726) 0.847

Conclusion

Before risk adjustment, a gender difference was suggested in the female group compared with the male in these current smoker South Korean AMI patients during a 2-year follow-up period. However, after adjustment, gender difference was not observed in these AMI patients with a history of current smoking.

P833Two-year clinical outcomes between statin with ACE inhibitor or ARB in patients with ST-segment elevation myocardial infarction after successful PCI with DES

Background

Limited comparative data are available.

Purpose

We decided to compare 2-year major clinical outcomes between statin with ACEI and statin ARB therapy in patients with STEMI after PCI with drug-eluting stents (DES).

Methods

A total 11706 STEMI patients who underwent PCI with DES and who prescribed statin were enrolled and they were divided into two groups, the statin with ACEI group (n=8705) and the statin with ARB group (n=3001). The primary endpoint was the major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-TVR. The secondary endpoints were the cumulative incidences of individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR.

Results

Two PSM groups (2835 pairs, n=5670, C-statistic = 0.680) were generated. The relative risk of MACE was higher in the statin with ARB group compared to statin with ACEI groups after propensity score-matched (PSM) analysis (hazard ratio [HR]: 1.323, 95% confidence interval [CI]: 1.085–1.613, p=0.006). The relative risks of cardiac death (HR: 1.831, 95% CI: 1.199–2.740, p=0.005), total repeat revascularization (HR: 1.487, 95% CI: 1.133–1.950, p=0.004), and non-TVR (HR: 1.696, 95% CI: 1.122–2.564, p=0.012) were also higher in the statin with ARB group after PSM.

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Statin + ACEI Statin + ARB Log-rank Propensity score matched Patients MACE 173 (6.5) 225 (8.5) 0.006 1.323 (1.085–1.613) 0.006 All-cause death 58 (2.2) 80 (3.0) 0.054 1.391 (0.992–1.950) 0.056 Cardiac death 35 (1.3) 63 (2.3) 0.004 1.831 (1.199–2.740) 0.005 Re-MI 39 (1.5) 44 (1.7) 0.548 1.141 (0.742–1.756) 0.548 Total repeat revascularization 88 (3.4) 128 (4.9) 0.004 1.487 (1.133–1.950) 0.004 TLR 26 (1.0) 40 (1.5) 0.075 1.561 (0.953–2.558) 0.077 TVR 53 (2.0) 71 (2.8) 0.086 1.364 (0.955–1.946) 0.088 Non-TVR 36 (1.4) 60 (2.3) 0.011 1.696 (1.122–2.564) 0.012 TVF 140 (5.3) 173 (6.6) 0.050 1.249 (1.000–1.561) 0.050

Conclusions

In this study, we suggest that the combination of statin with ACEI may be beneficial for reducing the cumulative incidences of MACE, total repeat revascularization rate, and non-TVR rather than the statin with ARB after PCI with DES in STEMI patients.

P5362Impact of statin therapy on long-term clinical outcomes between STEMI and NSTEMI after stent implantation

Background

Although European guideline recommends that statin should be given to all patients with acute myocardial infarction (AMI), irrespective of cholesterol concentration, limited studies were focused on the long-term effects of statin therapy between ST-segment elevation MI (STEMI) and non-ST-segment elevation MI (NSTEMI).

Purpose

The authors conducted the study to compare the relative beneficial role of statin on 2-year major clinical outcomes between STEMI and NSTEMI in patients who underwent successful PCI with DES.

Methods

Finally, a total of 26317 AMI patients who underwent stent implantation and who were prescribed the statin were enrolled and they were separated into two groups; the STEMI group (n=15002) and the NSTEMI group (n=11315). The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), total coronary revascularization (target lesion revascularization [TLR], target vessel revascularization [TVR], non-TVR) during 2-year follow-up period.

Results

After propensity score-matched (PSM) analysis, two PSM groups (7746 pairs, n=15492, C-statistic = 0.766) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, and cardiac death were significantly higher in the NSTEMI group. However, after PSM, the cumulative incidence of all-cause death (Hazard ratio, 1.386; 95% CI, 1.133–1.696; p=0.002) was significantly higher in the NSTEMI group. The cumulative incidences of MACE, cardiac death, re-MI, total revascularization, TLR, TVR, and non-TVR were similar between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value STEMI NSTEMI Log-rank Propensity score matched patients MACE 532 (7.2) 584 (8.1) 0.092 1.106 (0.984–1.244) 0.092 All-cause death 163 (2.2) 224 (3.1) 0.001 1.386 (1.133–1.696) 0.002 Cardiac death 121 (1.5) 148 (2.0) 0.088 1.232 (0.969–1.566) 0.089 Re-MI 117 (1.6) 107 (1.5) 0.545 0.922 (0.710–1.199) 0.545 Total revascularization 291 (4.1) 307 (4.4) 0.422 1.068 (0.910–1.254) 0.423 TLR 92 (1.3) 89 (1.2) 0.880 0.978 (0.731–1.309) 0.880 TVR 173 (2.4) 184 (2.6) 0.478 1.078 (0.876–1.327) 0.478 Non-TVR 123 (1.7) 130 (1.9) 0.593 1.070 (0.836–1.369) 0.539

Conclusion

The mortality reduction capability of statin was more prominent in the STEMI group compared with the NSTEMI group.

P5494Impact of the gender difference on long-term clinical outcomes in dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES

Background

There are limited comparative data concerning long-term major clinical outcomes between male and female in dyslipidemic AMI patients after PCI with new-generation DES.

Purpose

We thought to investigate the impact of gender difference on the 2-year clinical outcomes.

Methods

Finally, a total of 2403 eligible dyslipidemic AMI patients who underwent PCI with new-generation DES were enrolled and they were separated into two groups; the male group (n=1800) and the female group (n=603). The primary endpoint was major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), and target vessel revascularization (TVR). The secondary endpoints were the incidence of the individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR

Results

Two propensity score-matched (PSM) groups (422 pairs, n=844, C-statistic = 0.850) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, re-MI, and TVF were significantly higher in the female group compared with the male group. However, after propensity score-matched (PSM) analysis, the cumulative incidences of MACE (HR, 0.971; 95% CI, 0.628–1.501; p=0.895), all-cause death (HR, 1.061; 95% CI, 0.536–2.100; p=0.865), re-MI (HR, 1.212; 95% CI, 0.433–2.907; p=0.813), and TVF (HR, 0.764; 95% CI, 0.474–1.229; p=0.267) were similar between the two groups. In addition, the cumulative incidences of cardiac death, TLR, TVR were not significantly different between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Male Female Log-rank Propensity score matched patients MACE 41 (10.4) 40 (10.3) 0.895 0.971 (0.628–1.501) 0.895 All-cause death 16 (4.0) 17 (4.2) 0.865 1.061 (0.536–2.100) 0.865 Cardiac death 13 (3.3) 9 (2.2) 0.391 0.691 (0.295–1.616) 0.393 Re-MI 8 (2.0) 9 (2.4) 0.813 1.212 (0.433–2.907) 0.813 TLR 7 (1.8) 6 (1.6) 0.781 0.857 (0.298–2.550) 0.781 TVR 16 (4.3) 10 (2.7) 0.236 0.623 (0.283–1.373) 0.241 TVF 39 (10.2) 30 (7.8) 0.265 0.764 (0.474–1.229) 0.267

Conclusion

The gender difference was not apparent in these dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES during 2-year follow-up period.

P02.01 Analysis of Multimodal Intraoperative Monitoring During Intramedullary Spinal Ependymoma Surgery

BACKGROUND

To evaluate the validity of intraoperative somatosensory-evoked potential (SSEP) and motor-evoked potential (MEP) monitoring according to two different warning criteria for 6 months after intramedullary spinal ependymoma (IMSE) surgery.

MATERIAL AND METHODS

To evaluate the validity of intraoperative somatosensory-evoked potential (SSEP) and motor-evoked potential (MEP) monitoring according to two different warning criteria for 6 months after intramedullary spinal ependymoma (IMSE) surgery.

RESULTS

The success rates of SSEP and MEP monitoring were 84.9% and 83.7%, respectively. There was one indeterminate case in SSEP and six in MEP. All-or-none criterion in SSEP and MEP monitoring showed higher specificity, PPV, and DOR than 50% decline criterion during 6 months. During the follow up, 37 of 38 extremities (97.4%) and 21 of 29 extremities (72.4%) were observed the improvement of sensory and motor deficit, respectively. Seven indeterminate cases also showed good clinical outcomes. However, most patients remained some degree of neurologic deficit.

CONCLUSION

Many false positive and false negative results of SSEP and MEP monitoring occurred immediately postoperative period. All-or-none criterion was more beneficial for IMSE surgery than 50% decline criterion. This trend was maintained until 6 months after surgery.

P92 What is a benign notochordal cell tumour?

Objectives

Characteristics from a large systematic review.

Design

The first systematic review of benign notochordal cell tumours.

Subjects

All studies, in any language, published at any time, identified using specified search terms.

Methods

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Results

So-called benign notochordal cell tumours exhibited the following features: pain was the sole presenting symptom in 37/81 (45.7%) and neurological deficit in 36/81 (44.4%). Incidental discovery upon imaging was reported in 8/81 (9.9%). Radiologically, lesions were small, (≤30 millimetres at their maximum diameter) in 57/65 (87.7%), hypointense on T1 sequences and hyperintense on T2 sequences on magnetic resonance imaging (106/130; 81.5%), did not enhance following contrast administration (62/74; 83.8%) and were non-lytic (80/160; 50.0%). Histologically, these tumours lacked myxoid matrix (66/84; 78.6%) and nuclear atypia (100/112; 89.3%). In those managed conservatively, follow up was between 8.5 and 120 months. Most were stable at follow up (22/25; 88.0%), one lesion grew (4.0%), one patient died of an unrelated cause (4.0%) and outcome was not stated in one case (4.0%).

Conclusions

BNCTs exhibit a spectrum of features, none of which are pathognomonic and diagnosis is subjective. The majority of reports describe small, non-progressive, non-lytic lesions that lack contrast enhancement, intercellular myxoid matrix and nuclear atypia. They are nevertheless difficult to distinguish from small chordomas.

P25 Hydrogel systems to enhance the delivery of cell therapy for traumatic spinal cord injury

Objectives

Cell therapies are an emerging therapeutic approach for spinal cord injury. We assessed the survival and phenotype of olfactory ensheathing cells (OECs) in hydrogel delivery systems suitable for clinical use.

Design

Laboratory study.

Methods

Cell survival in different formulations of collagen and fibrin hydrogels was assessed using Syto 9 and propidium iodide. The proportion of cells staining positive for a key repair marker (p75NTR) was also quantified using immunocytochemistry and fluorescence microscopy.

Results

There were significant differences in OEC survival between the various collagen and fibrin hydrogel formulations tested (p<0.001 one-way ANOVA, n=17). 10% v/v fibrin conferred the best cell survival with 85% of OECs remaining alive. Incorporating OECs into collagen hydrogels promoted the highest proportion of p75NTR immunopositive cells (78%) and this was significantly higher than both fibrin hydrogels and traditional monolayer culture (53% and 20%, respectively, p<0.0001 one-way ANOVA, n=24).

Conclusions

Collagen and fibrin hydrogels both have the potential to enhance the delivery, survival and retention of transplanted OECs for spinal cord repair. Both materials are clinically scalable, promote favourable OEC survival and have the potential to increase the proportion of cells expressing a key repair marker (p75NTR). Optimised hydrogel delivery systems may provide a valuable approach to improve the delivery of OECs for spinal cord repair in the future.

Leukocytes as a reservoir of circulating oncogenic DNA and regulatory targets of tumor-derived extracellular vesicles

Essentials Tumor-bearing mice were employed to follow oncogenic HRAS sequences in plasma, and blood cells. Cancer DNA accumulated in leukocytes above levels detected in exosomes, platelets and plasma. Extracellular vesicles and nucleosomes are required for uptake of tumor DNA by leukocytes. Uptake of tumor-derived extracellular vesicles by leukocytes triggers coagulant phenotype.

SUMMARY

Background Tumor-derived extracellular vesicles (EVs) and free nucleosomes (NSs) carry into the circulation a wealth of cancer-specific, bioactive and poorly understood molecular cargoes, including genomic DNA (gDNA). Objective Here we investigated the distribution of extracellular oncogenic gDNA sequences (HRAS and HER2) in the circulation of tumor-bearing mice. Methods and Results Surprisingly, circulating leukocytes (WBCs), especially neutrophils, contained the highest levels of mutant gDNA, which exceeded the amount of this material recovered from soluble fractions of plasma, circulating EVs, platelets, red blood cells (RBCs) and peripheral organs, as quantified by digital droplet PCR (ddPCR). Tumor excision resulted in disappearance of the WBC-associated gDNA signal within 2-9 days, which is in line with the expected half-life of these cells. EVs and nucleosomes were essential for the uptake of tumor-derived extracellular DNA by neutrophil-like cells and impacted their phenotype. Indeed, the exposure of granulocytic HL-60 cells to EVs from HRAS-driven cancer cells resulted in a selective increase in tissue factor (TF) procoagulant activity and interleukin 8 (IL-8) production. The levels of circulating thrombin-antithrombin complexes (TAT) were markedly elevated in mice harboring HRAS-driven xenografts. Conclusions Myeloid cells may represent a hitherto unrecognized reservoir of cancer-derived, EV/NS-associated oncogenic gDNA in the circulation, and a possible novel platform for liquid biopsy in cancer. In addition, uptake of this material alters the phenotype of myeloid cells, induces procoagulant and proinflammatory activity and may contribute to systemic effects associated with cancer.

Molecular subtypes and differentiation programmes of glioma stem cells as determinants of extracellular vesicle profiles and endothelial cell-stimulating activities

We have previously uncovered the impact of oncogenic and differentiation processes on extracellular vesicles (EVs) in cancer. This is of interested in the context of glioma stem cells (GSC) that are responsible for recurrent nature of glioblastoma multiforme (GBM), while retaining the potential to undergo differentiation and self renewal.  GSCs reside in vascular niches where they interact with endothelial cells through a number of mediators including bioactive cargo of EVs. GSCs can be classified as proneural (PN) or mesenchymal (MES) subtypes on the basis of their gene expression profiles and distinct biological characteristics. In the present study we investigated how GSC diversity and differentiation programmes influence their EV-mediated communication potentials. Indeed, molecular subtypes of GBMs and GSCs differ with respect to their expression of EV-related genes (vesiculome) and GSCs with PN or MES phenotypes produce EVs with markedly different characteristics, marker profiles, proteomes and endothelial stimulating activities. For example, while EVs of PN GSC are largely devoid of exosomal markers their counterparts from MES GSCs express ample CD9, CD63 and CD81 tetraspanins. In both GSC subtypes serum-induced differentiation results in profound, but distinct changes of cellular phenotypes including the enhanced EV production, reconfiguration of their proteomes and the related functional pathways. Notably, the EV uptake was a function of both subtype and differentiation state of donor cells. Thus, while, EVs produced by differentiated MES GSCs were internalized less efficiently than those from undifferentiated cells they exhibited an increased stimulatory potential for human brain endothelial cells. Such stimulating activity was also observed for EVs derived from differentiated PN GSCs, despite their even weaker uptake by endothelial cells. These findings suggest that the role of EVs as biological mediators and biomarkers in GBM may depend on the molecular subtype and functional state of donor cancer cells, including cancer stem cells.

Abbreviations: CryoTEM: cryo-transmission electron microscopy; DIFF: differentiated GSCs; EGF: epidermal growth factor; DUC: differential ultracentrifugation; EV: extracellular vesicle; FGF: fibroblast growth factor; GBM: glioblastoma multiforme; GFAP: glial fibrillary acidic protein; GO: gene ontology; GSC: glioma stem cells; HBEC-5i: human brain endothelial cells; MES: mesenchymal cells; MTS - [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt; PMT1: proneural-to-mesenchyman transition cell line 1; PN: proneural cells; TEM: transmission electron microscopy; WB: western blotting

Compressive Sensing with Optical Chaos

Compressive sensing (CS) is a technique to sample a sparse signal below the Nyquist-Shannon limit, yet still enabling its reconstruction. As such, CS permits an extremely parsimonious way to store and transmit large and important classes of signals and images that would be far more data intensive should they be sampled following the prescription of the Nyquist-Shannon theorem. CS has found applications as diverse as seismology and biomedical imaging. In this work, we use actual optical signals generated from temporal intensity chaos from external-cavity semiconductor lasers (ECSL) to construct the sensing matrix that is employed to compress a sparse signal. The chaotic time series produced having their relevant dynamics on the 100 ps timescale, our results open the way to ultrahigh-speed compression of sparse signals.