Impact of early protein provision on the mortality of acute critically ill stroke patients

BACKGROUND

Stroke is the leading cause of death in China, and dysphagia is a common symptom of stroke. For acute critically ill stroke patients, whether the protein provision overwhelming calorie provision impacts the outcome still requires investigation.

MATERIALS AND METHODS

We conducted a retrospectively observational study. Acute stroke patients admitted to our neurocritical care unit between January 2013 and January 2017 were enrolled. Primary end points were short-term (30-day) and long-term (6-month) mortality, as well as long-term poor outcome with a modified Rankin scale score ≥4.

RESULTS

Of 208 eligible patients, 127 (61.1%) patients were diagnosed with acute ischemic stroke and 81 (38.9%) with intracranial hemorrhage. In multivariate logistic regression analysis, the increased protein provision was significantly associated with reduced 30-day and 6-month mortality (P = .041 and P = .020, respectively) but not 6-month functional outcome (P = .365), whereas calorie provision had no independent association with either mortality or functional outcome. When the protein provision ≤1.74 g/kg/day, there was a 9.37% decrease in short-term mortality and a 9.21% decrease in long-term mortality with each 0.1 g/kg/day increase in protein delivery. The patients were further divided into five subgroups based on the amount of protein provision, and Linear-by-Linear Association tests showed there was a negative linear relationship between the protein provision and 30-day and 6-month mortality (P = .048 and P = .017, respectively).

CONCLUSIONS

Early protein provision during the first week is an independent predictor of short-term and long-term mortality in acute critically ill stroke patients.

A Review of Monitoring Methods for Cerebral Blood Oxygen Saturation

In recent years, cerebral blood oxygen saturation has become a key indicator during the perioperative period. Cerebral blood oxygen saturation monitoring is conducive to the early diagnosis and treatment of cerebral ischemia and hypoxia. The present study discusses the three most extensively used clinical methods for cerebral blood oxygen saturation monitoring from different aspects: working principles, relevant parameters, current situations of research, commonly used equipment, and relative advantages of different methods. Furthermore, through comprehensive comparisons of the methods, we find that near-infrared spectroscopy (NIRS) technology has significant potentials and broad applications prospects in terms of cerebral oxygen saturation monitoring. Despite the current NIRS technology, the only bedside non-invasive cerebral oxygen saturation monitoring technology, still has many defects, it is more in line with the future development trend in the field of medical and health, and will become the main method gradually.

In Situ Monitoring the Potassium-Ion Storage Enhancement in Iron Selenide with Ether-Based Electrolyte

As one of the promising anode materials, iron selenide has received much attention for potassium-ion batteries (KIBs). Nevertheless, volume expansion and sluggish kinetics of iron selenide result in the poor reversibility and stability during potassiation-depotassiation process. In this work, we develop iron selenide composite matching ether-based electrolyte for KIBs, which presents a reversible specific capacity of 356 mAh g^-1 at 200 mA g^-1 after 75 cycles. According to the measurement of mechanical properties, it is found that iron selenide composite also exhibits robust and elastic solid electrolyte interphase layer in ether-based electrolyte, contributing to the improvement in reversibility and stability for KIBs. To further investigate the electrochemical enhancement mechanism of ether-based electrolyte in KIBs, we also utilize in situ visualization technique to monitor the potassiation-depotassiation process. For comparison, iron selenide composite matching carbonate-based electrolyte presents vast morphology change during potassiation-depotassiation process. When changing to ether-based electrolyte, a few minor morphology changes can be observed. This phenomenon indicates an occurrence of homogeneous electrochemical reaction in ether-based electrolyte, which results in a stable performance for potassium-ion (K-ion) storage. We believe that our work will provide a new perspective to visually monitor the potassium-ion storage process and guide the improvement in electrode material performance.

Glycocalyx is critical for blood-brain barrier integrity by suppressing caveolin1-dependent endothelial transcytosis following ischemic stroke

The breakdown of the blood‐brain barrier (BBB) is related to the occurrence and deterioration of neurological dysfunction in ischemic stroke, which leads to the extravasation of blood‐borne substances, resulting in vasogenic edema and increased mortality. However, a limited understanding of the molecular mechanisms that control the restrictive properties of the BBB hinders the manipulation of the BBB in disease and treatment. Here, we found that the glycocalyx (GCX) is a critical factor in the regulation of brain endothelial barrier integrity. First, endothelial GCX displayed a biphasic change pattern, of which the timescale matched well with the biphasic evolution of BBB permeability to tracers within the first week after t‐MCAO. Moreover, GCX destruction with hyaluronidase increased BBB permeability in healthy mice and aggravated BBB leakage in transient middle cerebral artery occlusion (t‐MCAO) mice. Surprisingly, ultrastructural observation showed that GCX destruction was accompanied by increased endothelial transcytosis at the ischemic BBB, while the tight junctions remained morphologically and functionally intact. Knockdown of caveolin1 (Cav1) suppressed endothelial transcytosis, leading to reduced BBB permeability, and brain edema. Lastly, a coimmunoprecipitation assay showed that GCX degradation enhanced the interaction between syndecan1 and Src by promoting the binding of phosphorylated syndecan1 to the Src SH2 domain, which led to rapid modulation of cytoskeletal proteins to promote caveolae‐mediated endocytosis. Overall, these findings demonstrate that the dynamic degradation and reconstruction of GCX may account for the biphasic changes in BBB permeability in ischemic stroke, and reveal an essential role of GCX in suppressing transcellular transport in brain endothelial cells to maintain BBB integrity. Targeting GCX may provide a novel strategy for managing BBB dysfunction and central nervous system drug delivery.

A semi-supervised zero-shot image classification method based on soft-target

Zero-shot learning (ZSL) aims at training a classification model with data only from seen categories to recognize data from disjoint unseen categories. Domain shift and generalization capability are two fundamental challenges in ZSL. In this paper, we address them with a novel Soft-Target Semi-supervised Classification (STSC) model. Specifically, an autoencoder network is leveraged, where both labeled seen data from the seen categories and unlabeled ancillary data collected from Internet or other datasets are employed as two branches, respectively. For the branch of labeled seen data, side information are employed as the latent vectors to separately connect the input of encoder and the output of decoder. In this way, visual and side information are implicitly aligned. For the branch of unlabeled ancillary data, it explicitly strengthens the reconstruction ability of the network. Meanwhile, these ancillary data can be viewed as a smooth to the domain distribution, which contributes to the alleviation of the domain shift problem. To further guarantee the generation ability, a Softmax-T loss function is proposed by making full use of the soft target. Extensive experiments on three benchmark datasets show the superiority of the proposed approach under tasks of both traditional zero-shot learning and generalized zero-shot learning.

AB0050 A NOVEL METHOD FOR ISOLATION OF EXOSOMES FROM SYNOVIAL FLUID

Background:

Exosomes in synovial fluid (SF) has a close relationship with the pathogenesis of rheumatiod arthritis. As a complex biological fluid, SF presents challenges for exosomes isolation using standard methods, such as ExoquickTM kit and ultracentrifugation.

Objectives:

The study aims to compared the quality of exosomes separated by ExoquickTM kit (TM), ExoquickTM kit+ExoquickTC kit (TM-TC), ultracentrifugation (UC) and TM-TC+UC(TM-TC-UC) from SF.

Methods:

Exosomes was separated by TM, TM-TC, UC and TM-TC-UC respectively. The size and concentrations of exosomes were detected by high sensitivity flow cytometry for nanoparticle analysis. Total protein and RNA were extracted from exosomes. SDS-PAGE was used to detect the protein distribution of exosomes. Western blot was used to examine the level of albumin and exosomes marker (TSG101 and CD81).

Results:

There was no statistic difference in the diameters of exosomes separated by the four methods. The concentrations of exosomes in TM, TM-TC, TM-TC-UC and UC were (5.65±0.93), (3.02±1.19), (1.67±0.25) and (4.61±0.73) *109Particles/mL. The protein concentrations of exosomes separated by the four methods were consistent with the concentrations of exosomes. SDS-PAGE showed that the protein distribution of exosomes separated by the four methods were different. Low levels of albumin were detected in TM-TC and TM-TC-UC, while high levels of albumin in TM and UC. Total RNA concentrations from exosomes in TM-TC was higher than other groups.

Conclusion:

TM-TC can be used to obtain higher quality exosomes from SF for the study of exosome-enriched components.

References:

[1]Helwa I, et al, A Comparative Study of Serum Exosome Isolation Using Differential Ultracentrifugation and Three Commercial Reagents. PloS one, 2017. 12(1): p. e0170628-e0170628.

Figure 1.

A: SDS-PAGE showed the protein distribution of exosomes; B: the detection of albumin, TSG101 and CD81 by western blot.

Disclosure of Interests:

None declared

POS0817 A NOVEL MODEL TO ASSESS DISEASE ACTIVITY IN TAKAYASU ARTERITIS BASED ON 18F-FDG-PET/CT: A CHINESE COHORT STUDY

Background:

Takayasu arteritis (TA) is a condition characterized by major large-vessel vasculitis (LVV), and is most commonly found in young women (age <40 years) of East Asia countries. 18F-FDG-PET/CT has been widely used in the diagnosis and follow-up of cancers to gather functional information based on metabolic activity. In the present study, we evaluated the value of different parameters in 18F-FDG-PET/CT for assessing active TA disease, and we establish a simple, quantifiable, and effective disease activity evaluation model based on 18F-FDG-PET/CT. A comparison in the ability to identify active disease was performed between the established Kerr score and the new 18F-FDG-PET/CT was also performed.

Objectives:

To investigate the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in assessing disease activity in TA.

Methods:

Ninety-one patients with TA, were recruited from a Chinese cohort from October 2017 to January 2019. Clinical data, acute-phase reactants (APRs), and 18F-FDG-PET/CT findings were simultaneously recorded. The Physician Global Assessment was used as the gold standard to assess TA disease activity. The value of using 18F-FDG-PET/CT to identify active disease was evaluated, using erythrocyte sedimentation rate (ESR) as a reference. Disease activity assessment models were constructed and concordance index (C-index), net reclassification index (NRI), and integrated discrimination index (IDI) were evaluated to compare the benefits of the new modes with ESR and Kerr score.

Results:

In total, 64 (70.3%) cases showed active disease. Higher levels of ESR and CRP, and lower interleukin (IL)-2R levels, were observed in active cases. 18F-FDG-PET/CT parameters, including SUVmean, SUVratio1, SUVratio2, sum of SUVmean, and sum of SUVmax, were significantly higher in active disease groups. The C index threshold of ESR to indicate active disease was 0.78 (95% CI: 0.69-0.88). The new activity assessment model combining ESR, sum of SUVmean, and IL-2R showed significant improvement in C index over the ESR method (0.96 vs. 0.78, P < 0.01; NRI 1.63, P < 0.01; and IDI 0.48, P < 0.01). The new model also demonstrated modest superiority to Kerr score assessment (0.96 vs. 0.87, P = 0.03; NRI 1.19, P < 0.01; and IDI 0.33 P < 0.01).

Conclusion:

A novel 18F-FDG-PET/CT-based method that involves combining the sum of SUVmean with ESR score and IL-2R levels demonstrated superiority in identifying active TA compared to conventional methods.

References:

[1]Kerr GS, Hallahan CW, Giordano J, Leavitt RY, Fauci AS, Rottem M, et al. Takayasu arteritis. Ann Intern Med 1994;120:919-29.

[2]Hoffman GS, Ahmed AE. Surrogate markers of disease activity in patients with Takayasu arteritis. A preliminary report from The International Network for the Study of the Systemic Vasculitides (INSSYS). Int J Cardiol 1998;66 Suppl 1:S191-4; discussion S195.

[3]Misra R, Danda D, Rajappa SM, Ghosh A, Gupta R, Mahendranath KM, et al. Development and initial validation of the Indian Takayasu Clinical Activity Score (ITAS2010). Rheumatology (Oxford) 2013;52:1795-801.

[4]Bardi M, Diamantopoulos AP. EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice summary. Radiol Med 2019;124:965-972.

[5]Spick C, Herrmann K, Czernin J. 18F-FDG PET/CT and PET/MRI Perform Equally Well in Cancer: Evidence from Studies on More Than 2,300 Patients. J Nucl Med 2016;57:420-30.

Disclosure of Interests:

None declared

A novel multifunctional platform based on ITO/APTES/ErGO/AuNPs for long-term cell culture and real-time biomolecule monitoring

Integrating long-term cell culture with real-time electrochemical monitoring is a promising strategy for future studies of physiological and pathological processes. However, great challenges still remain in fabricating such a platform with satisfactory electrochemical performance as well as desirable biocompatibility. Herein, we proposed a novel multifunctional platform based on gold nanoparticles/electrochemically reduced graphene oxide/3-aminopropyl-triethoxysilane modified indium tin oxide plate (ITO/APTES/ErGO/AuNPs). The unique biological and electrical properties of AuNPs and ErGO endow the platform with superior electrocatalytic activity and desirable biocompatibility. As a proof of concept, the present platform showed satisfactory electrochemical performance for sensitive and selective detection of hydrogen peroxide (H₂O₂) with a sensitivity about 0.25 μA μM^-1 cm^-2 and a detection limit of 0.38 μM in a linear range of 0.5-1461 μM. And the principle of catalytic reduction was clarified through density functional calculations (DFT). Furthermore, cells grew on the platform exhibited excellent proliferation ability and considerable viability after a long-term cultivation. Based on those desirable performances, in-situ and real-time monitoring of endogenously produced H₂O₂ released from cancer cells cultured on the platform has been successfully realized, which will be of great significance in pathophysiology research.

POS0187 THE PROGNOSTIC FACTORS IN PREDICTING RELAPSE FOR IGG4-RELATED DISEASE: A LONG-TERM STUDY BASED ON THE CLINICAL AND PATHOLOGICAL CHARACTERISTICS OF THE PATIENTS

Background:

The relationship between the pathological findings and disease relapse has not been well established.

Objectives:

We aim to investigate the clinical and pathological manifestations in relation with disease relapse in IgG4-RD, as well as identify prognostic factors in predicting relapsed disease.

Methods:

This study enrolled 71 patients newly diagnosed with IgG4-RD between Jan 2011 and April 2020, all of whom had received pathological examinations. Their pathological manifestations and clinical data were collected. Multivariate Cox regression and AUC (area under curve) were used to identify predictors for relapsed disease and assess the predictive value of these predictors, respectively.

Results:

During a follow-up period of 26 (range, 6-123) months, 4.2% (3/71) patients died. The remaining 68 patients were all treated with glucocorticoids with or without immunosuppressor continuously. By the end of follow-up, 47 (69.1%) patients sustained clinical remission, and 21 (30.9%) patients suffered relapsed disease with a median relapse time at 10 (6-30) months. We found that IgG4 ≥ 6.5g/L (OR 1.52-11.06), IgG ≥ 20.8g/L (OR 1.11-7.23), IgG4-RD responder index (RI) ≥ 9 (OR 1.28-11.37), and more IgG4+ plasma cell infiltration (≥ 60 / HPF in visceral organs, or ≥ 200 / HPF in head and neck organs) (OR 1.79-22.41) were all independent predictive factors for disease relapse. A prognostic score was explored for predicting recurrence in IgG4-RD, including three predictive factors (IgG ≥ 20.8g/L, IgG4-RD RI ≥9, and more IgG4+ plasma cell infiltration). The three-year relapse rate for the patients with no, one, two, and three risk factors were 0%, 27.3%, 66.7%, and 100%, respectively.

Conclusion:

Patients’ earlier IgG4 ≥ 6.5g/L, IgG ≥ 20.8g/L, IgG4-RD RI ≥9, and more IgG4+ plasma cell infiltration independently predicted disease relapse. We explored a prognostic score for predicting recurrence in IgG4-RD include three predictive factors (IgG ≥ 20.8g/L, IgG4-RD RI ≥9, and more IgG4+ plasma cell infiltration), which might be used to evaluate the risk of recurrence in IgG4-RD.

References:

[1]DESHPANDE V, ZEN Y, CHAN J K, et al. Consensus statement on the pathology of IgG4-related disease[J]. Mod Pathol,2012,25(9): 1181-1192.

[2]JENNETTE J C, FALK R J, BACON P A, et al. 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides[J]. Arthritis Rheum,2013,65(1): 1-11.

[3]OKAZAKI K, UMEHARA H. Are Classification Criteria for IgG4-RD Now Possible? The Concept of IgG4-Related Disease and Proposal of Comprehensive Diagnostic Criteria in Japan[J]. Int J Rheumatol,2012,2012: 357071.

[4]SHIMOSEGAWA T, CHARI S T, FRULLONI L, et al. International consensus diagnostic criteria for autoimmune pancreatitis: guidelines of the International Association of Pancreatology[J]. Pancreas,2011,40(3): 352-358.

[5]OHARA H, OKAZAKI K, TSUBOUCHI H, et al. Clinical diagnostic criteria of IgG4-related sclerosing cholangitis 2012[J]. J Hepatobiliary Pancreat Sci,2012,19(5): 536-542.

[6]KAWANO M, SAEKI T, NAKASHIMA H, et al. Proposal for diagnostic criteria for IgG4-related kidney disease[J]. Clin Exp Nephrol,2011,15(5): 615-626.

[7]GOTO H, TAKAHIRA M, AZUMI A. Diagnostic criteria for IgG4-related ophthalmic disease[J]. Jpn J Ophthalmol,2015,59(1): 1-7.

[8]MATSUI S, YAMAMOTO H, MINAMOTO S, et al. Proposed diagnostic criteria for IgG4-related respiratory disease[J]. Respir Investig,2016,54(2): 130-132.

[9]WEN ZHANG J H S. Management of IgG4-related disease[J]. Lancet Rheumatol,2019,1: e55-e65.

[10]EBBO M, DANIEL L, PAVIC M, et al. IgG4-related systemic disease: features and treatment response in a French cohort: results of a multicenter registry[J]. Medicine (Baltimore),2012,91(1): 49-56.

Disclosure of Interests:

None declared

A refractory anti-NMDA receptor encephalitis successfully treated by bilateral salpingo-oophorectomy and intrathecal injection of methotrexate and dexamethasone: a case report

Introduction

Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is an autoimmune-mediated disease that is common in young female patients with ovarian teratomas. With appropriate immunotherapy, most patients achieve a good prognosis. Nevertheless, some patients may be refractory to first- and second-line immunotherapy, thus alternative treatments are required for these patients.

Case presentation: We present a case of anti-NMDA receptor encephalitis with ovarian teratoma. After the prompt removal of the teratoma and intense immunotherapy was administered, including an intravenous methylprednisolone pulse, intravenous immunoglobin, plasmapheresis, immunoadsorption, intravenous cyclophosphamide, and rituximab, the patient’s neurologic status did not improve. Bilateral salpingo-oophorectomy was then conducted, and intrathecal injection of methotrexate (MTX) and dexamethasone (DXM) was performed. The patient’s neurological symptoms improved dramatically, and she achieved a good prognosis after 23 months.

Conclusions

Intrathecal injection of MTX and DXM may be beneficial for treatment of refractory cases of anti-NMDA receptor encephalitis. Additional research is required to elucidate the mechanisms of intrathecal treatment with this therapy.

Bismuth oxychloride anchoring on graphene nanosheets as anode with a high relative energy density for potassium ion battery

In this work, we developed bismuth oxychloride anchoring on graphene nanosheets (BiOCl/G) composite via a simple one-step hydrothermal process for KIBs' anode, which delivers a high reversible specific capacity of 251 mAh g^-1 at 50 mA g^-1 after 50 cycles. Meanwhile, our BiOCl/G composite also exhibits a low voltage plateau during potassiation-depotassiation process, and such low voltage plateau in anode is helpful to improve the energy density of the full battery. In addition, we also provide the energy changes for migration of K-ion of our composite according to the density functional theory calculation and the result shows that the introduction of graphene in BiOCl can reduce the adsorption energy variation, which is in favor of K-ion intercalation process. In consideration of low potential plateau of our composite, we also introduce a new evaluation method, relative energy density (E_R), which not only includes the specific capacity, but also combines the potential plateau of the anode materials during potassiation-depotassiation process. According to the calculation, our BiOCl/G composite obtain an ultra-high E_R of 541 Wh kg^-1 at 50 mA g^-1 after 50 cycles with a relative energy conversion efficiency of 81%.

[Realization of non-invasive blood glucose detector based on nonlinear auto regressive model and dual-wavelength]

The use of non-invasive blood glucose detection techniques can help diabetic patients to alleviate the pain of intrusive detection, reduce the cost of detection, and achieve real-time monitoring and effective control of blood glucose. Given the existing limitations of the minimally invasive or invasive blood glucose detection methods, such as low detection accuracy, high cost and complex operation, and the laser source's wavelength and cost, this paper, based on the non-invasive blood glucose detector developed by the research group, designs a non-invasive blood glucose detection method. It is founded on dual-wavelength near-infrared light diffuse reflection by using the 1 550 nm near-infrared light as measuring light to collect blood glucose information and the 1 310 nm near-infrared light as reference light to remove the effects of water molecules in the blood. Fourteen volunteers were recruited for in vivo experiments using the instrument to verify the effectiveness of the method. The results indicated that 90.27% of the measured values of non-invasive blood glucose were distributed in the region A of Clarke error grid and 9.73% in the region B of Clarke error grid, all meeting clinical requirements. It is also confirmed that the proposed non-invasive blood glucose detection method realizes relatively ideal measurement accuracy and stability.

Deep Attentive Video Summarization With Distribution Consistency Learning

This article studies supervised video summarization by formulating it into a sequence-to-sequence learning framework, in which the input and output are sequences of original video frames and their predicted importance scores, respectively. Two critical issues are addressed in this article: short-term contextual attention insufficiency and distribution inconsistency. The former lies in the insufficiency of capturing the short-term contextual attention information within the video sequence itself since the existing approaches focus a lot on the long-term encoder-decoder attention. The latter refers to the distributions of predicted importance score sequence and the ground-truth sequence is inconsistent, which may lead to a suboptimal solution. To better mitigate the first issue, we incorporate a self-attention mechanism in the encoder to highlight the important keyframes in a short-term context. The proposed approach alongside the encoder-decoder attention constitutes our deep attentive models for video summarization. For the second one, we propose a distribution consistency learning method by employing a simple yet effective regularization loss term, which seeks a consistent distribution for the two sequences. Our final approach is dubbed as Attentive and Distribution consistent video Summarization (ADSum). Extensive experiments on benchmark data sets demonstrate the superiority of the proposed ADSum approach against state-of-the-art approaches.

Few-Shot Human-Object Interaction Recognition With Semantic-Guided Attentive Prototypes Network

Extreme instance imbalance among categories and combinatorial explosion make the recognition of Human-Object Interaction (HOI) a challenging task. Few studies have addressed both challenges directly. Motivated by the success of few-shot learning that learns a robust model from a few instances, we formulate HOI as a few-shot task in a meta-learning framework to alleviate the above challenges. Due to the fact that the intrinsical characteristic of HOI is diverse and interactive, we propose a Semantic-guided Attentive Prototypes Network (SAPNet) framework to learn a semantic-guided metric space where HOI recognition can be performed by computing distances to attentive prototypes of each class. Specifically, the model generates attentive prototypes guided by the category names of actions and objects, which highlight the commonalities of images from the same class in HOI. In addition, we design two alternative prototypes calculation methods, i.e., Prototypes Shift (PS) approach and Hallucinatory Graph Prototypes (HGP) approach, which explore to learn a suitable category prototypes representations in HOI. Finally, in order to realize the task of few-shot HOI, we reorganize 2 HOI benchmark datasets with 2 split strategies, i.e., HICO-NN, TUHOI-NN, HICO-NF, and TUHOI-NF. Extensive experimental results on these datasets have demonstrated the effectiveness of our proposed SAPNet approach.

Enhancing the photodetection performance of MAPbI3 perovskite photodetectors by a dual functional interfacial layer for color imaging

The color imaging capacity of recently developed perovskite photodetectors (PDs) has not been fully explored. In this Letter, we fabricate a CH₃NH₃PbI₃ (MAPbI₃) PD as a color imaging sensor mainly due to its almost flat spectral response in a full visible light region. To enhance the photodetection performance, we introduce a dual functional interfacial TiO₂ layer by atomic layer deposition, reducing the dark current to 12 pA from 13 nA and improving the photocurrent to 1.87 µA from 20 nA, resulting in a ∼10⁵ fold enhancement of the ON/OFF ratio. Since we obtained satisfactory color images, we believe that the MAPbI₃ perovskite PD is an ideal photosensitive device for color imaging.

Cerebral autoregulation is heterogeneous in different stroke mechanism of ischemic stroke caused by intracranial atherosclerotic stenosis

BACKGROUND AND PURPOSE

Intracranial atherosclerotic stenosis (ICAS) is the most common cause of ischemic stroke (IS) and is associated with stroke recurrence. It results in IS due to a variety of mechanisms. However, the influence of brain reserve mechanism on different stroke mechanism is still unclear. Cerebral autoregulation (CA) is an important brain reserve mechanism and is impaired after IS. This study aimed to explore the impaired pattern of CA and assess the association between CA and stroke risk factors in different stroke mechanism caused by ICAS.

METHODS

IS patients with ICAS (50%-99% stenosis/occlusion) in middle cerebral artery (MCA) or internal carotid artery were enrolled to receive CA examinations within 7 days after onset. Healthy volunteers were also recruited as controls. CA was recorded from spontaneous fluctuations of blood pressure and MCA flow velocity. Transfer function analysis was used to derive CA parameters, including phase difference (PD) and coherence in the low-frequency range (0.06-0.12 Hz).

RESULTS

A total of 89 IS patients and 90 healthy controls were included. Compared with controls, CA was impaired ipsilaterally in patients with parent artery atherosclerosis occluding penetrating artery (POPA) while CA was bilaterally impaired in other stroke mechanisms. And CA on ipsilateral hemisphere was correlated with hypertension/hyperlipidemia in patients with POPA (r = -0.481, p = .008; r = -0.484, p = .008). While CA on ipsilateral hemisphere was correlated with perfusion parameter including the arterial spin-labeling (ASL) parameter cerebral blood flow (CBF) (r = 0.893, p = .007) and collateral circulation status the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) (r = 0.610, p = .021) in patients with hypoperfusion mechanism.

CONCLUSION

In IS patients, CA was impaired heterogeneously and was correlated with different risk factors in varied stroke mechanism. CA can be as an informative determinant of stroke risk in patients with ICAS and to help improving individualized treatment strategies in the presence of ischemic stroke caused by ICAS.

Biomarkers of Unfavorable Outcome in Acute Ischemic Stroke Patients with Successful Recanalization by Endovascular Thrombectomy

<b><i>Background:</i></b> We aimed to identify plasma markers of unfavorable outcomes for patients with acute ischemic stroke (AIS) after recanalization by endovascular thrombectomy (EVT). <b><i>Methods:</i></b> From November 2017 to May 2019, we prospectively collected 61 AIS patients due to anterior large vessel occlusion who achieved recanalization by EVT. Plasma samples were obtained between 18 and 24 h after recanalization. Unfavorable outcomes included futile recanalization at 90 days and overall early complications within 7 days after EVT. <b><i>Results:</i></b> After adjustment for age and initial National Institute of Health Stroke Scale (NIHSS), matrix metalloproteinase-9 (MMP-9), tenascin-C, thioredoxin, ADAMTS13, and gelsolin were independently associated with both futile recanalization and overall early complications significantly (all <i>p</i> &#x3c; 0.05), while C-reactive protein (CRP) was independently associated with overall early complications (<i>p</i> = 0.031) but at the limit of significance for futile recanalization (<i>p</i> = 0.051). The baseline clinical model (BCM) (including age and initial NIHSS) demonstrated discriminating ability to indicate futile recanalization (area under the curve [AUC] 0.807, 95% confidence interval [CI] 0.693–0.921) and overall early complications (AUC 0.749, 95% CI 0.611–0.887). BCM+MMP-9+thioredoxin enhanced discrimination (AUC 0.908, 95% CI 0.839–0.978, <i>p</i> = 0.043) and reclassification (net reclassification improvement [NRI] 67.2%, <i>p</i> &#x3c; 0.001) to indicate futile recanalization. With respect to overall early complications, BCM+MMP-9+tenascin-C, BCM+MMP-9+CRP, BCM+MMP-9+ADAMTS13, BCM+tenascin-C+ADAMTS13, and BCM+CRP+ADAMTS13, all improved discrimination (AUC [95% CI]: 0.868 [0.766–0.970], 0.882 [0.773–0.990], 0.886 [0.788–0.984], 0.880 [0.783–0.977], and 0.863 [0.764–0.962], respectively, all <i>p</i> &#x3c; 0.05 by the DeLong method) and reclassification (NRI 59.1%, 71.8%, 51.1%, 67.4%, and 38.3%, respectively, all <i>p</i> &#x3c; 0.05). <b><i>Conclusions:</i></b> The increased levels of MMP-9, tenascin-C, CRP, thioredoxin, and decreased levels of ADAMTS13 and gelsolin were independent predictors of futile recanalization in AIS patients after recanalization by EVT.

A novel fluorescence probe for rapid and sensitive detection of tetracyclines residues based on silicon quantum dots

A novel rapid and sensitive fluorescence probe based on silicon quantum dots (Si QDs) fluorescence was fabricated for selective detection of tetracyclines (TCs) residues. Si QDs were innovatively prepared via facile One-Pot Solvent-Free Method and characterized by TEM, FT-IR, UV absorption, fluorescence, XPS and XRD. In aqueous solution, Cu²⁺ and Si QDs complexed together and the fluorescence of Si QDs quenched (static quenching) to a certain extent. TCs can be early in binding to Cu²⁺ and prevent Si QDs fluorescence quenching. As a consequence, quantitative screening of TCs can be achieved. The assay is highly selective for TCs. Represented by chlortetracycline (CTC), a member of TCs, under optimized conditions, good linear relationship in the range of 11.32-1086.72 nM was obtained, and the detection limit (LOD; S/N ratio = 3) of this assay for CTC is 0.92 nM. It was successfully applied to the determination of CTC in spiked bee honey and total TCs in actual honey samples. And the evaluation of selectivity, reproducibility and stability of the probe were favorable. These results demonstrated that the presented fluorescent probe can be a promising sensing platform for TCs analysis.