[Pay attention to the futile recanalization management of patients with acute ischemic stroke].

Vascular recanalization therapy has been proven to be one of the most effective treatments for acute ischemic stroke (AIS) worldwide. Recently, the neurological functions have dramatically improved for AIS patients receiving endovascular thrombectomy, especially after the issue and promotion of evidence from different clinical studies. But nearly 50% of the patients had unfavorable clinical outcome even after successful recanalization [modified thrombolysis in cerebral infarction (mTICI)≥2b/3], which was termed as"futile recanalization". The mechanisms are complex, which may be related to poor collateral circulation, microthrombus and small artery reocclusion. The most significant pathophysiological change is brain tissue hypoperfusion although complete opening of the large artery, known as"no-reflow phenomenon". Therefore, it is urgent to manage the complications after vascular recanalization, such as hemorrhagic transformation, hyperperfusion syndrome, vascular re-occlusion, and even surgery-related complications (arterial dissection, contrast-induced encephalopathy), and future research is warranted to focus on the strategy of drugs with multi-target protection combined with vascular recanalization treatment. The current article covers the review, original research and case report focusing on this topic, aiming to raise clinical questions and call for more contribution to explore the mechanism and potential therapeutic strategy of futile recanalization, and thus provides more selections on the improvement of clinical outcome for AIS patients.

[Construction and quality assurance of metagenomic next-generation sequencing platform in pathogen detection].

Early diagnosis remains the key to prevent and control infectious diseases. In recent years, metagenomic next-generation sequencing (mNGS) technology breaks through the limitations of conventional culture methods or targeted molecular detection methods. It improves the diagnosis and treatment level of difficult and rare infectious pathogens through the shotgun high-throughput sequencing to conduct unbiased and rapid detection of microorganisms in clinical samples, which has been widely recognized in clinical practice. Due to the complex detection process of mNGS, there are no uniform specifications and requirements at present. Meanwhile, most laboratories lack of relevant talents at the initial stage of platform establishment, which poses severe challenges to the construction and quality control of the mNGS platform. Based on the practical experience in the construction and operation of the mNGS laboratory of Peking Union Medical College Hospital, the current article summarizes the hardware requirements for the establishment of the mNGS laboratory, the establishment and evaluation methods of the mNGS testing system and the quality assurance after the clinical application, and comprehensively introduces the suggestions for the standardized construction and operation of the mNGS testing platform and quality management system.

[Analysis of factors associated with futile recanalization after endovascular treatment for acute ischemic stroke with large vessels occlusion in anterior intracranial circulation].

Objective: To analyze the related factors of futile recanalization (FR) after emergency endovascular treatment of large artery occlusion in anterior circulation. Methods: Three studies on endovascular treatment of acute anterior circulation large vessels occlusion stroke were selected, and their data were merged for retrospective analysis. Patients were divided into the FR group and favorable prognosis group according to the functional prognosis. Risk factor analysis was conducted using multivariate logistic regression. Results: A total of 1 581 patients were finally included, with 858 (48.9%) patients in favorable prognosis group and 926 (51.91%) patients in FR group. Among them, there were 939 males and 642 females, with a mean age of (65±12) years. Multivariate logistic regression analysis showed that National Institute of Health Stroke Scale (NIHSS) score (OR=1.089,95%CI:1.066-1.113), puncture to recanalization time (OR=0.756, 95%CI:0.586-0.971), age (OR=1.04,95%CI:1.029-1.051), serum glucose (OR=1.101,95%CI:1.062-1.143), systolic blood pressure (OR=1.005,95%CI:1.001-1.010), passes≥3(OR=1.941,95%CI:1.294-2.941)Alberta stroke program early CT (ASPECT) score (OR=0.919,95%CI:0.847-0.996), occlusion site (M1 segment of middle cerebral artery, OR=0.744,95%CI:0.565-0.980) and collateral circulation [(2 points, OR=0.757, 95%CI:0.581-0.985); (3-4 points, adjusted OR=0.640, 95%CI: 0.472-0.866)] were independent factors of FR. Conclusion: The incidence of FR in patients with large artery occlusion in anterior circulation who achieve satisfied reperfusion after endovascular treatment is high. Higher NIHSS score, longer puncture to recanalization time, older age, higher serum glucose and systolic blood pressure are risk factors, while lower ASPECTS, occlusion in cerebral middle M1 segment, better collateral circulation are protective factors.

Visible wide-angle view imaging system for the first plasma on the HL-2M tokamak.

The wide-angle view imaging system, in terms of a tangential view diagnostic with field of view (FOV) of 56.8° and a downward-looking diagnostic from the top of the machine with FOV of 94.7°, has been newly constructed for the first plasma of the HL-2M tokamak achieved in December 2020. Its mission in this stage is to monitor the plasma evolution during its startup, sustainment, and disruption in the visible spectral range as well as the plasma-wall interaction. For the latter ultrawide view diagnostic, nearly three-quarters of the divertor region and half the area of the inner wall are in the view range. Both the diagnostics are characterized by a similar optical structure, i.e., the light emission from the plasma is collected by a front-end lens and transferred through an imaging fiber bundle to the camera. This optical structure is suitable for application in the complex tokamak environment mainly because the fiber bundle is flexible. Photos of glow discharges are acquired prior to the first plasma for testing the FOVs in the vacuum vessel. The spatial resolution is ∼4mm for the tangential view diagnostic and ∼10mm for the downward-looking diagnostic. The temporal resolutions, ranging from 90 to 360 Hz by changing the region of interest or binning acquisition mode of the color camera, are applied to record the plasma evolutions and/or dust creation events during the first plasma campaign.

Plasma metabolome alteration in dairy cows with left displaced abomasum before and after surgical correction.

Left displaced abomasum (LDA) leads to substantial changes in the metabolism of dairy cows. Surgical correction of LDA can rapidly improve the health of cows; however, changes in metabolism following surgery are rarely described. To investigate the changes of plasma metabolome in cows with LDA before and after surgical correction, blood samples were collected from 10 healthy postpartum cows and 10 cows with LDA on the day of diagnosis, then again from the LDA cows 14 d after surgery. Serum nonesterified fatty acid, ß-hydroxybutyric acid, cortisol and histamine concentration, and antioxidant enzyme (superoxide dismutase and glutathione peroxidase) activities were evaluated, and the metabolic profile in plasma was analyzed using ultra-high-performance liquid chromatography time-of-flight mass spectrometry. The results demonstrated that cows with LDA experienced severe negative energy balance and oxidative stress, which can be improved by surgical correction. The metabolic profile was analyzed using multidimensional and univariate statistical analyses, and different metabolites were identified. In total, 102 metabolites differed between cows with LDA and healthy cows. After surgical correction, 65 metabolites changed in cows with LDA, compared with these cows during the LDA event. Following surgical correction, AA levels tended to increase, and lipid levels tended to decrease in cows with LDA. Pathway analysis indicated marked changes in linoleic acid metabolism, Arg biosynthesis, and Gly, Ser, and Thr metabolism in cows at the onset of LDA and following surgical correction. Surgical treatment reversed the changes in AA and lipid metabolism in cows with LDA.

Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas.

The synchronization of geodesic acoustic modes (GAMs) and magnetic fluctuations is identified in the edge plasmas of the HL-2A tokamak. Mesoscale electric fluctuations (MSEFs) having components of a dominant GAM, and m/n=6/2 potential fluctuations are found at the same frequency as that of the magnetic fluctuations of m/n=6/2 (m and n are poloidal and toroidal mode numbers, respectively). The temporal evolutions of the MSEFs and the magnetic fluctuations clearly show the frequency entrainment and the phase lock between the GAM and the m/n=6/2 magnetic fluctuations. The results indicate that GAMs and magnetic fluctuations can transfer energy through nonlinear synchronization. Such nonlinear synchronization may also contribute to low-frequency zonal flow formation, reduction of turbulence level, and thus confinement regime transitions.

Evaluation of the stability of reference genes in bone mesenchymal stem cells from patients with avascular necrosis of the femoral head.

This study aimed to evaluate 12 genes (18S, GAPDH, B2M, ACTB, ALAS1, GUSB, HPRT1, PBGD, PPIA, PUM1, RPL29, and TBP) for their reliability and stability as reference sequences for real-time quantitative PCR (RT-qPCR) in bone marrow-derived mesenchymal stem cells (BMSCs) isolated from patients with avascular necrosis of the femoral head (ANFH). BMSCs were isolated from 20 ANFH patients divided into four groups according to etiology, and four donors with femoral neck fractures. Total RNA was isolated from BMSCs and reverse transcribed into complementary DNA, which served as a template for RT-qPCR. Three commonly used programs were then used to analyze the results. Reference gene expression varied within each group, between specific groups, and among all five groups. Based on comparisons of all five groups, two of the programs used suggested that HPRT1 was the most stable reference gene, while 18S and ACTB were the most variable. Among the 12 candidate reference genes, HPRT1 exhibited the greatest reliability, followed by PPIA. Thus, these sequences could be used as references for the normalization of RT-qPCR results.

Dynamics of low-intermediate-high-confinement transitions in toroidal plasmas.

The dynamic features of the low-intermediate-high-(L-I-H) confinement transitions on HL-2A tokamak are presented. Here we report the discovery of two types of limit cycles (dubbed type-Y and type-J), which show opposite temporal ordering between the radial electric field and turbulence intensity. In type-Y, which appears first after an L-I transition, the turbulence grows first, followed by the localized electric field. In contrast, the electric field leads type-J. The turbulence-induced zonal flow and pressure-gradient-induced drift play essential roles in the two types of limit cycles, respectively. The condition of transition between types-Y and -J is studied in terms of the normalized radial electric field. An I-H transition is demonstrated to occur only from type-J.

A universal fast algorithm for sensitivity-based structural damage detection.

Structural damage detection using measured response data has emerged as a new research area in civil, mechanical, and aerospace engineering communities in recent years. In this paper, a universal fast algorithm is presented for sensitivity-based structural damage detection, which can quickly improve the calculation accuracy of the existing sensitivity-based technique without any high-order sensitivity analysis or multi-iterations. The key formula of the universal fast algorithm is derived from the stiffness and flexibility matrix spectral decomposition theory. With the introduction of the key formula, the proposed method is able to quickly achieve more accurate results than that obtained by the original sensitivity-based methods, regardless of whether the damage is small or large. Three examples are used to demonstrate the feasibility and superiority of the proposed method. It has been shown that the universal fast algorithm is simple to implement and quickly gains higher accuracy over the existing sensitivity-based damage detection methods.

Frequency-resolved nonlinear turbulent energy transfer into zonal flows in strongly heated L-mode plasmas in the HL-2A tokamak.

The absolute rate of nonlinear energy transfer among broadband turbulence, low-frequency zonal flows (ZFs) and geodesic acoustic modes (GAMs) was measured for the first time in fusion-grade plasmas using two independent methods across a range of heating powers. The results show that turbulent kinetic energy from intermediate frequencies (20-80 kHz) was transferred into ZFs and GAMs, as well as into fluctuations at higher frequencies (>80 kHz). As the heating power was increased, the energy transfer from turbulence into GAMs and the GAM amplitudes increased, peaked and then decreased, while the energy transfer into the ZFs and the ZFs themselves increased monotonically with heating power. Thus there exists a competition between ZFs and GAMs for the transfer of turbulent energy, and the transfer into ZFs becomes dominant as the heating power is increased. The poloidal-radial Reynolds stress and the mean radial electric field profiles were also measured at different heating powers and found to be consistent with the energy transfer measurement. The results suggest that ZFs play an important role in the low-to-high (L-H) plasma confinement transition.

[Research advances on the pathogenesis and diagnosis of pyoderma gangrenosum].

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis, closely associated with the immune system. Its pathogenesis is currently not clear. The lack of specificity in the clinical manifestations and histopathological changes of PG leads to a long clinical diagnosis cycle and even misdiagnosis, which is easy to delay treatment or promote the deterioration of ulcer wound. The diagnosis of this disease is still very difficult, which poses a great challenge to wound repair practitioners. This article reviews the research advances on the pathophysiology, clinical features, and diagnosis of PG in recent years, with the aim of providing reference for relevant clinical practitioners.

Visible imaging system with changeable field of view on the HL-2A tokamak.

A new visible imaging system characterizing a flexible optical design and delivering high resolution frames is established on the HL-2A tokamak. It features a modular configuration, consisting of a front-end imaging lens, a set of bilateral telecentric relay lenses, and a camera. To avoid the effects of plasma radiation (x and gamma-rays) and magnetic field variation on the camera, it should be away from the coils. Therefore, the length of the relay lenses determines the total size of the imaging system. The main feature of this imaging system is to realize the variation of field of view (FOV) by interchanging the front-end prime lenses or by using a zoom lens directly rather than designing the optical system afresh, which lowers the cost drastically. The primary purpose of varying FOV is to enrich the versatility of this system, i.e., focusing on a narrow FOV such as gas puff imaging or a wide FOV such as the plasma cross sections. During the HL-2A experiments, this visible imaging system is used to provide high quality pictures of the plasma-wall interaction, divertor detachment, pellet injections, and so on. The frames confirmed that a strong radiation close to the X point is correlated with the completely detached inner target.

[Diagnosis and endoscopic treatment of blunt laryngeal trauma with arytenoid injury].

Objective: To investigate the clinical characteristics, diagnosis, endoscopic surgical procedures, and therapeutic effect of blunt laryngeal trauma with arytenoid injury. Methods: We retrospectively reviewed 12 patients who suffered blunt laryngeal trauma with laryngeal mucosa avulsion and arytenoid region injury at the Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital from April 2007 to December 2018. Among the 12 patients, 10 were males, 2 were females, aged from 7 to 48 years old, with a median age of 21 years old. All patients were performed with transoral endoscopic laryngeal microsurgery under general anesthesia. Clinical characteristics, laryngoscopic signs, laryngeal CT, endoscopic surgical findings and procedures, and therapeutic effect were analyzed. The subjective and objective parameters of the voice quality of patients before and after surgery were compared using SPSS 22.0 statistical software by paired T test. Results: All patients had a history of obvious dysphonia immediately after trauma, accompanied by throat pain and hemoptysis without obvious dyspnea and dysphagia. Slight subcutaneous emphysema was found in 3 patients by physical examination. Laryngoscope revealed that 14 sides of vocal folds immobilized, arytenoid and/or ventricular region and posterior glottis mucosa were avulsed in 4 patients within 48 h of injury, and arytenoid cartilage was exposed in 4 sides. The arytenoid and ventricular regions were covered with thick pseudo-membrane or granulation, with abnormal structure in 8 patients with damage of more than 48 h. Intraoperative exploration revealed that there were 17 sides of arytenoid region (bilateral 5 cases, unilateral 7 cases) with varying degrees of injury. There was only limited laceration on three sides of the vocal folds. The lateral ventricular and vocal fold mucosae were avulsed vertically from the arytenoid region and arytenoid cartilage was exposed in 14 sides, among which 6 sides had abnormal arytenoid cartilage morphology and 8 sides had fracture displacement. Laryngeal CT showed irregular thickening of lateral glottis and/or supratroglottic structures in patients with vocal folds immobility, among which asymmetry of arytenoid cartilage structure on both sides in 3 cases and displacement in 2 cases were found. Restoration and microsuture of the fractured arytenoid, perichondrium and avulsion laryngeal mucosa under the direct laryngoscope were performed. The degree of dysphonia was significantly improved immediately after laryngeal microsurgery, the voice significantly improved in G, R, B, A, jitter, shimmer, NHR, and MPT three months after surgery(t=12.792, 12.792, 10.340, 3.276, 2.865, 3.781, 3.173, 3.090, respectively, P<0.05). Except for 1 patient with scar on vocal fold, all the other patients had normal laryngeal morphology and normal vocal fold movement. No laryngeal stenosis was found during the follow-up period. Conclusions: For patients with blunt laryngeal trauma, the injury of arytenoid region and arytenoid cartilage should be evaluated if there is obvious hoarseness, vocal fold immobility, avulsion of ventricular/vocal folds mucosa, or structural abnormality of arytenoid region under laryngoscopic examination. For highly suspected cases, microrphonosurgery under the direct laryngoscope should be performed as soon as possible, which can effectively reduce the occurrence of vocal fold movement disorders and laryngeal scar/stenosis, reconstruct the normal laryngeal structure, and restore the vocal function.

A remote gain controlled and polarization angle tunable Doppler backward scattering reflectometer.

Remote control of the diagnostic systems is the basic requirement for the high performance plasma operation in a fusion device. This work presents the development of the remote control system for the multichannel Doppler backward scattering (DBS) reflectometers. It includes a remote controlled quasi-optical system and a remote intermediate frequency (IF) amplifier gain control system. The quasi-optical system contains a rotational polarizer, its polarization angle is tunable through a remote controlled motor, and it could combine the microwave beams with a wide frequency range into one focused beam. The remote IF gain control system utilizes the digital microcontroller (MCU) technique to regulate the signal amplitude for each signal channel. The gain parameters of amplifiers are adjustable, and the feedback of working status in the IF system will be sent to MCU in real time for safe operation. The gain parameters could be controlled either by the Ethernet remote way or directly through the local control interface on the system. Preliminary experimental results show the effectiveness of the remote controlled multichannel DBS system.

Development of solid state terahertz interferometer for the first plasma on HL-2M tokamak.

A solid state terahertz interferometer has been developed on the recent commissioned HL-2M tokamak. It can work in a wide frequency region of 220-325 GHz, and the terahertz wave is generated from a low frequency phase locked voltage controlled oscillator with the frequency multiplying technique. A phase processor based on field programmable gate array (FPGA) technology is designed for the heterodyne interferometer, and it contributes to real-time display of electron density. To extract phase information, a novel numerical algorithm related to fast Fourier transform is written on the FPGA chip and enables one to obtain phase shift without being affected by amplitude variation induced by plasma absorption or frequency modulation from the outer electromagnetic environment. The interferometer achieves minimum measurable electron density in the order of 1016 m-3. With the plasma diagnosis, electron density and low frequency tearing mode have been measured during the first experimental campaign.

ß-induced Alfvén eigenmodes destabilized by energetic electrons in a Tokamak plasma.

The ß-induced Alfvén eigenmode (BAE) excited by energetic electrons has been identified for the first time both in the Ohmic and electron cyclotron resonance heating plasma in HL-2A. The features of the instability, including its frequency, mode number, and propagation direction, can be observed by magnetic pickup probes. The mode frequency is comparable to that of the continuum accumulation point of the lowest frequency gap induced by the shear Alfvén continuous spectrum due to finite ß effect, and it is proportional to Alfvén velocity at thermal ion ß held constant. The experimental results show that the BAE is related not only with the population of the energetic electrons, but also their energy and pitch angles. The results indicate that the barely circulating and deeply trapped electrons play an important role in the mode excitation.

Observation of a spontaneous particle-transport barrier in the HL-2A tokamak.

Using the profile analysis, the density perturbation transport analysis, and the Doppler reflectometry measurement, for the first time a spontaneous and steady-state particle-transport barrier has been evidenced in the Ohmic plasmas in the HL-2A tokamak with no externally applied momentum or particle input except the gas puffing. A threshold in density has been found for the observation of the barrier. The particle diffusivity is well-like, and the convection is found to be inward outside the well and outward inside the well. The formation of the barrier coincides with the transition between the trapped electron mode and the ion temperature gradient driven mode.

Age-Dependent Changes in the Plasma Proteome of Healthy Adults.

OBJECTIVE: Human blood plasma is a complex that communicates with most parts of the body and reflects the changes in the state of an organism. Identifying age-related biomarkers can help predict and monitor age-related physiological decline and diseases and identify new treatments for diseases. METHODS AND PARTICIPANTS: In this study, TMT-LC-MS/MS was utilized to screen differentially expressed plasma proteins in 118 healthy adults of different ages. Participants were divided into three groups: 21-30 years of age (Young), 41-50 years of age (Middle) and ≥60 years of age (Old). RESULTS: The number of differentially expressed proteins in the comparisons of Young vs Middle, Middle vs Old and Young vs Old were 82, 22 and 99, respectively. These proteins were involved in numerous physiological processes, such as "negative regulation of smooth muscle cell proliferation" and "blood coagulation". Moreover, when Young was compared with Middle or Old, "complement and coagulation cascades" was the top enriched pathway by KEGG pathway enrichment analysis. Functional phenotyping of the proteome demonstrated that the plasma proteomic profiles of young adults were strikingly dissimilar to those of the middle-aged or older adults. CONCLUSIONS: The results of this study mapped the variation in the expression of plasma proteins and provided information about possible biomarkers/treatments for different age-related functional disorders.

Fast charge exchange recombination spectroscopy on HuanLiu-2A tokamak.

A Fast Charge eXchange Recombination Spectroscopy (CXRS) diagnostic with eight radial channels has been implemented on a HuanLiu-2A (HL-2A) tokamak with a time resolution of up to 10 kHz monitoring helium II spectra or 1 kHz monitoring carbon VI spectra. The crucial aspects of the fast CXRS are to improve the spectral intensity and the acquisition frequency. The spectral intensity has been greatly enhanced by customized fiber bundles. The main boost in optimizing the acquisition frequency is achieved by binning more pixel rows of the charge coupled device (CCD) representing one radial channel and by reducing the effective image area of the CCD. Consequently, the sawtooth oscillations of ion temperature and rotation velocity are continuously observed for the first time in the HL-2A tokamak.

Validation of reference genes for the normalization of RT-qPCR expression studies on human laryngeal cancer and hypopharyngeal cancer.

OBJECTIVE: Selecting stably expressed reference genes is crucial for evaluating real-time quantitative polymerase chain reaction (RT-qPCR) data via the relative quantification method. In the present-day study, our aim was to select optimal reference genes (RGs) for the investigation of target gene (TG) expression profiling in cancerous human laryngeal and hypopharyngeal tissues. PATIENTS AND METHODS: 12 cancerous laryngeal tissues and 10 cancerous hypopharyngeal tissues were investigated. The expression characteristics of 11 reference genes (18S rRNA, GAPDH, B2M, ACTB, TBP, ALAS1, RPL29, HMBS, HPRT1, GUSB, and PUM1), which were commonly used in RT-qPCR for the analysis of gene expression, were investigated using the geNorm, NormFinder, and BestKeeper algorithm programs. RESULTS: HMBS, ALAS1, and B2M were suggested as optimal RGs for studying human laryngeal and hypopharyngeal cancerous tissues together, laryngeal cancerous tissue by itself, and hypopharyngeal cancerous tissue by itself, respectively. If 2 or more reference genes are needed to achieve better standardization, 3 reference genes can optimally be used in combination to improve the accuracy of relative quantitation normalization. The recommended combinations for studying human laryngeal and hypopharyngeal cancerous tissues together, laryngeal cancerous tissue by itself, and hypopharyngeal cancerous tissue by itself were HMBS + HPRT1 + GUSB, ALAS1 + GUSB + HMBS, and B2M + HPRT1 + TBP, respectively. CONCLUSIONS: The recommended reference genes could be used to improve the accuracy of gene expression studies on the molecular mechanisms of cancerous human laryngeal and hypopharyngeal tissues. The selected combination of reference genes can effectively improve the accuracy of the relative quantitative diagnosis of gene expression levels, such as messenger RNA, circular RNA, and long-noncoding RNA.