Atomic-level polarization reversal in sliding ferroelectric semiconductors

Intriguing "slidetronics" has been reported in van der Waals (vdW) layered non-centrosymmetric materials and newly-emerging artificially-tuned twisted moiré superlattices, but correlative experiments that spatially track the interlayer sliding dynamics at atomic-level remain elusive. Here, we address the decisive challenge to in-situ trace the atomic-level interlayer sliding and the induced polarization reversal in vdW-layered yttrium-doped γ-InSe, step by step and atom by atom. We directly observe the real-time interlayer sliding by a 1/3-unit cell along the armchair direction, corresponding to vertical polarization reversal. The sliding driven only by low energetic electron-beam illumination suggests rather low switching barriers. Additionally, we propose a new sliding mechanism that supports the observed reversal pathway, i.e., two bilayer units slide towards each other simultaneously. Our insights into the polarization reversal via the atomic-scale interlayer sliding provide a momentous initial progress for the ongoing and future research on sliding ferroelectrics towards non-volatile storages or ferroelectric field-effect transistors.

[Clinical and prognostic analysis of opsoclonus-myoclonus-ataxia syndrome in children]

Objective: To summarize the clinical and prognostic features of children with opsoclonus-myoclonus-ataxia syndrome (OMAS). Methods: A total of 46 patients who met the diagnostic criteria of OMAS in the Department of Neurology, Beijing Children's Hospital from June 2015 to June 2023 were retrospectively analyzed. Centralized online consultations or telephone visits were conducted between June and August 2023. The data of the children during hospitalization and follow-up were collected, including clinical manifestations, assistant examination, treatment and prognosis. According to the presence or absence of tumor, the patients were divided into two groups. The chi-square test or Mann-Whitney U test was used to compare the differences between the two groups. Univariate Logistic regression was used to analyze the factors related to OMAS recurrence and prognosis. Results: There were 46 patients, with 25 males and the onset age of 1.5 (1.2, 2.4) years. Twenty-six (57%) patients were diagnosed with neuroblastoma during the course of the disease, and no patients were categorized into the high-risk group. A total of 36 patients (78%) were followed up for≥6 months, and all of them were treated with first-line therapy with glucocorticoids, gammaglobulin and (or) adrenocorticotrophic hormone. Among the 36 patients, 9 patients (25%) were treated with second-line therapy for ≥3 months, including rituximab or cyclophosphamide, and 17 patients (47%) received chemotherapy related to neuroblastoma. At the follow-up time of 4.2 (2.2, 5.5) years, 10 patients (28%) had relapsed of OMAS. The Mitchell and Pike OMS rating scale score at the final follow-up was 0.5 (0, 2.0). Seven patients (19%) were mildly cognitively behind their peers and 6 patients (17%) were severely behind. Only 1 patient had tumor recurrence during follow-up. The history of vaccination or infection before onset was more common in the non-tumor group than in the tumor group (55%(11/20) vs. 23%(6/26), χ²=4.95, P=0.026). Myoclonus occurred more frequently in the non-tumor group (40%(8/20) vs. 4%(1/26), χ²=7.23, P=0.007) as the onset symptom. Univariate Logistic regression analysis showed that the tumor group had less recurrence (OR=0.19 (0.04-0.93), P=0.041). The use of second-line therapy or chemotherapy within 6 months of the disease course had a better prognosis (OR=11.64 (1.27-106.72), P=0.030). Conclusions: OMAS in children mostly starts in early childhood, and about half are combined with neuroblastoma. Neuroblastoma in combination with OMAS usually has a low risk classification and good prognosis. When comparing patients with OMAS with and without tumors, the latter have a more common infection or vaccination triggers, and myoclonus, as the onset symptom, is more common. Early addition of second-line therapy is associated with better prognosis in OMAS.

Low-k nano-dielectrics facilitate electric-field induced phase transition in high-k ferroelectric polymers for sustainable electrocaloric refrigeration

Ferroelectric polymer-based electrocaloric effect may lead to sustainable heat pumps and refrigeration owing to the large electrocaloric-induced entropy changes, flexible, lightweight and zero-global warming potential. Herein, low-k nanodiamonds are served as extrinsic dielectric fillers to fabricate polymeric nanocomposites for electrocaloric refrigeration. As low-k nanofillers are naturally polar-inactive, hence they have been widely applied for consolidate electrical stability in dielectrics. Interestingly, we observe that the nanodiamonds markedly enhances the electrocaloric effect in relaxor ferroelectrics. Compared with their high-k counterparts that have been extensively studied in the field of electrocaloric nanocomposites, the nanodiamonds introduces the highest volumetric electrocaloric enhancement (~23%/vol%). The resulting polymeric nanocomposite exhibits concurrently improved electrocaloric effect (160%), thermal conductivity (175%) and electrical stability (125%), which allow a fluid-solid coupling-based electrocaloric refrigerator to exhibit an improved coefficient of performance from 0.8 to 5.3 (660%) while maintaining high cooling power (over 240 W) at a temperature span of 10 K.

A ferroelectric fin diode for robust non-volatile memory

Among today's nonvolatile memories, ferroelectric-based capacitors, tunnel junctions and field-effect transistors (FET) are already industrially integrated and/or intensively investigated to improve their performances. Concurrently, because of the tremendous development of artificial intelligence and big-data issues, there is an urgent need to realize high-density crossbar arrays, a prerequisite for the future of memories and emerging computing algorithms. Here, a two-terminal ferroelectric fin diode (FFD) in which a ferroelectric capacitor and a fin-like semiconductor channel are combined to share both top and bottom electrodes is designed. Such a device not only shows both digital and analog memory functionalities but is also robust and universal as it works using two very different ferroelectric materials. When compared to all current nonvolatile memories, it cumulatively demonstrates an endurance up to 1010 cycles, an ON/OFF ratio of ~102, a feature size of 30 nm, an operating energy of ~20 fJ and an operation speed of 100 ns. Beyond these superior performances, the simple two-terminal structure and their self-rectifying ratio of ~ 104 permit to consider them as new electronic building blocks for designing passive crossbar arrays which are crucial for the future in-memory computing.

Multiresistance states in ferro- and antiferroelectric trilayer boron nitride

Stacking two atomic layers together can induce interlayer (sliding) ferroelectricity that is absent in their naturally occurring crystal forms. With the flexibility of two-dimensional materials, more layers could be assembled to give rise to even richer polarization states. Here, we show that three-layer boron nitride can host ferro- and antiferroelectric domains in the same sample. When used as a tunneling junction, the polarization of these domains could be switched in a layer-by-layer procedure, producing multiple resistance states. Theoretical investigation reveals an important role played by the interaction between the trilayer boron nitride and graphene substrate. These findings reveal the great potential and unique properties of 2D sliding ferroelectric materials.

Ferroelectric-defined reconfigurable homojunctions for in-memory sensing and computing

Recently, the increasing demand for data-centric applications is driving the elimination of image sensing, memory and computing unit interface, thus promising for latency- and energy-strict applications. Although dedicated electronic hardware has inspired the development of in-memory computing and in-sensor computing, folding the entire signal chain into one device remains challenging. Here an in-memory sensing and computing architecture is demonstrated using ferroelectric-defined reconfigurable two-dimensional photodiode arrays. High-level cognitive computing is realized based on the multiplications of light power and photoresponsivity through the photocurrent generation process and Kirchhoff's law. The weight is stored and programmed locally by the ferroelectric domains, enabling 51 (>5 bit) distinguishable weight states with linear, symmetric and reversible manipulation characteristics. Image recognition can be performed without any external memory and computing units. The three-in-one paradigm, integrating high-level computing, weight memorization and high-performance sensing, paves the way for a computing architecture with low energy consumption, low latency and reduced hardware overhead.

Prediction of progesterone receptor expression in high-grade meningioma by using radiomics based on enhanced T1WI

AIM

To predict progesterone receptor (PR) expression of high-grade meningioma using radiomics based on enhanced T1-weighted imaging (WI).

MATERIALS AND METHODS

There were 157 cases of high-grade meningioma in the study. Seventy-eight cases had negative expression and 79 cases had positive expression. Spearman's rank correlation coefficient and least absolute shrinkage and selection operator (LASSO) regression were used to select the valuable features. The models were developed by naive Bayes (NB), random forest (RF), and support vector machine (SVM). Receiver operating characteristic (ROC) and decision curve analysis (DCA) analysis were used to assess the models.

RESULTS

Nine features were selected as the valuable features using Spearman's analysis and LASSO regression. The RF and NB models achieved the same area under the ROC curve (AUC) of 0.75, which was higher than that of SVM (0.74). There was no significant difference among the AUCs of the three models (p>0.05). There was a larger net benefit in the RF model than the SVM and NB models across all threshold probabilities in the DCA analysis.

CONCLUSION

The RF model had good performance in predicting PR expression of high-grade meningioma. PR expression evaluation for high-grade meningioma would be helpful in clinical practice.

Ultralow-power in-memory computing based on ferroelectric memcapacitor network

Analog storage through synaptic weights using conductance in resistive neuromorphic systems and devices inevitably generates harmful heat dissipation. This thermal issue not only limits the energy efficiency but also hampers the very-large-scale and highly complicated hardware integration as in the human brain. Here we demonstrate that the synaptic weights can be simulated by reconfigurable non-volatile capacitances of a ferroelectric-based memcapacitor with ultralow-power consumption. The as-designed metal/ferroelectric/metal/insulator/semiconductor memcapacitor shows distinct 3-bit capacitance states controlled by the ferroelectric domain dynamics. These robust memcapacitive states exhibit uniform maintenance of more than 104 s and well endurance of 109 cycles. In a wired memcapacitor crossbar network hardware, analog vector-matrix multiplication is successfully implemented to classify 9-pixel images by collecting the sum of displacement currents (I = C × dV/dt) in each column, which intrinsically consumes zero energy in memcapacitors themselves. Our work sheds light on an ultralow-power neural hardware based on ferroelectric memcapacitors.

FoxO1/NLRP3 Inflammasome Promotes Age-Related Alveolar Bone Resorption

Periodontitis is the utmost common chronic oral disease that exhibits intense susceptibility to aging. Aging is characterized by persistent sterile low-grade inflammation, leading to age-related periodontal complications represented by alveolar bone loss. Currently, forkhead transcription factor O1 (FoxO1) is generally believed to have a significant role in body development, senescence, cell viability, and oxidative stress in numerous organs and cells. However, the role of this transcription factor in mediating age-related alveolar bone resorption has not been examined. In this study, FoxO1 deficiency was discovered to have a beneficial correlation with halting the progression of alveolar bone resorption in aged mice. To further investigate the function of FoxO1 in age-related alveolar bone resorption, osteoblastic-specific FoxO1 knockout mice were generated, leading to an amelioration in alveolar bone loss compared to aged-matched wild-type mice, manifested as enhanced osteogenic potential. Mechanistically, we identified enhancement of the NLRP3 inflammasome signaling in FoxO1-deficient osteoblasts in the high dose of reactive oxygen species. Concordant with our study, MCC950, a specific inhibitor of NLRP3 inflammasome, greatly rescued osteoblast differentiation under oxidative stress. Our data shed light on the manifestations of FoxO1 depletion in osteoblasts and propose a possible mechanism for the therapy of age-related alveolar bone loss.

Predictors of postoperative biochemical remission in lower Knosp grade growth hormone-secreting pituitary adenomas: a large single center study

PURPOSE

Growth hormone-secreting pituitary adenomas (GH-PAs) with a low Knosp grade are typically associated with a good postoperative biochemical remission (BR) rate. However, a proportion of patients do not achieve remission. In this study, we aimed to investigate predictive factors of postoperative remission for lower Knosp GH-PAs.

METHODS

In this retrospective study, we enrolled 140 patients who were diagnosed with lower Knosp (0-2) GH-PAs and received trans-sphenoidal surgery between December 2016 and June 2021 from the largest pituitary tumor surgery center in southern China. The univariate, binary Logistic regression, and receiver operating characteristic curve (ROC) analyses were employed to determine independent predictors and cutoff values of remission. The postoperative outcome was defined as remission using the 2010 consensus criteria of acromegaly.

RESULTS

One hundred and thirty six patients (97.1%) achieved gross total resection. The postoperative long-term BR was 68.6%. Empty sella, tumor maximum diameter and postoperative GH levels were independent factors predicting remission. ROC revealed that postoperative 24 h GH ≤ 1.3 ng/mL and  ≤ 1.23 ng/mL were valuable predictors for 3-month and long-term remission respectively, and that postoperative 3-month GH ≤ 1.6 ng/mL and tumor maximum diameter  ≤ 17 mm were predictors for delayed remission.

CONCLUSION

Early postoperative GH levels can be used as predictors of remission. However, BR was not associated with preoperative somatostatin analogs therapy or Knosp grade (0-2). For patients without residual tumor or recurrence and whose GH levels are slightly elevated within 1 year after surgery, adjuvant treatments may not be necessary.

[Endoscopic resection of type D trigeminal schwannoma through nasal sinus approach]

Objective: To examine the feasibility and surgical approach of removing type D trigeminal schwannoma through nasal cavity and nasal sinus under endoscope. Methods: Eleven patients with trigeminal schwannoma who were treated in the Department of Otorhinolaryngology, Qilu Hospital of Shandong University from December 2014 to August 2021 were analyzed retrospectively in this study. There were 7 males and 4 females, aged (47.5±13.5) years (range: 12 to 64 years). The neoplasm involved the pterygopalatine fossa, infratemporal fossa, ethmoidal sinus, sphenoid sinus, cavernous sinus, and middle cranial fossa. The size of tumors were between 1.6 cm×2.0 cm×2.0 cm and 5.7 cm×6.0 cm×6.0 cm. Under general anesthesia, the tumors were resected through the transpterygoid approach in 4 cases, through the prelacrimal recess approach in 4 cases, through the extended prelacrimal recess approach in 2 cases, and through the endoscopic medial maxillectomy approach in 1 case. The nasal endoscopy and imaging examination were conducted to detect whether neoplasm recurred or not, and the main clinical symptoms during follow-up. Results: All the surgical procedures were performed under endonasal endoscope, including Gross total resection in 10 patients. The tumor of a 12-year-old patient was not resected completely due to huge tumor size and limited operation space. One patient was accompanied by two other schwannomas located in the occipital region and the ipsilateral parotid gland region originating from the zygomatic branch of the facial nerve, both of which were removed concurrently. After tumor resection, the dura mater of middle cranial fossa was directly exposed in the nasal sinus in 2 cases, including 1 case accompanied by cerebrospinal fluid leakage which was reconstructed by a free mucosal flap obtained from the middle turbinate, the other case was packed by the autologous fat to protect the dura mater. The operation time was (M(IQR)) 180 (160) minutes (range: 120 to 485 minutes). No complications and deaths were observed. No recurrence was observed in the 10 patients with total tumor resection during a 58 (68) months' (range: 10 to 90 months) follow-up. No obvious change was observed in the facial appearance of all patients during the follow-up. Conclusion: Type D trigeminal schwannoma involving pterygopalatine fossa and infratemporal fossa can be removed safely through purely endoscopic endonasal approach by selecting the appropriate approach according to the size and involvement of the tumor.

[Research progress of interstitial lung disease combined with lung cancer]

Interstitial lung disease combined with lung cancer (ILD-LC) has attracted more and more attention. Interstitial lung disease (ILD) is an independent risk factor of lung cancer. ILD and lung cancer have common pathogenesis of promoting fibrosis and promoting cancer, so they are not only comorbidities. This review updated the epidemiology, pathogenesis and incidence and risk factors of treatment-induced acute exacerbation(including surgery, chemotherapy, and radiotherapy)in ILD-LC. The purpose is to improve the understanding, individual management and quality of life of patients in ILD-LC.

A very low frequency (VLF) antenna based on clamped bending-mode structure magnetoelectric laminates

As the development of wireless communication devices tends to be highly integrated, the miniaturization of very low frequency (VLF) antenna units has always been an unresolved issue. Here, a novel VLF mechanical communication antenna using magnetoelectric (ME) laminates with bending-mode structure is realized. ME laminates combines magnetostrictive Metglas amorphous ribbons and piezoelectric 0.7Pb(Mg_1/3Nb_2/3)O₃-0.3PbTiO₃single crystal plates. From the simulation, we confirmed that the ME laminates can reduce the resonance peak from 18 kHz to 7.5 kHz by bending-mode structure. Experiment results show the resonance frequency can be farther reduced to 6.3 kHz by clamping one end of the ME antenna. The ME laminate exhibits a giant converse ME coefficient of 6 Oe cm V^-1at 6.3 kHz. The magnetic flux density generated by the ME antenna has been tested along with distance ranging from 0 to 60 cm and it is estimated that a 1 fT flux could be detected around 100 m with an excitation power of 10 mW.

Ultralow-Power Machine Vision with Self-Powered Sensor Reservoir

A neuromorphic visual system integrating optoelectronic synapses to perform the in-sensor computing is triggering a revolution due to the reduction of latency and energy consumption. Here it is demonstrated that the dwell time of photon-generated carriers in the space-charge region can be effectively extended by embedding a potential well on the shoulder of Schottky energy barrier. It permits the nonlinear interaction of photocurrents stimulated by spatiotemporal optical signals, which is necessary for in-sensor reservoir computing (RC). The machine vision with the sensor reservoir constituted by designed self-powered Au/P(VDF-TrFE)/Cs2 AgBiBr6 /ITO devices is competent for both static and dynamic vision tasks. It shows an accuracy of 99.97% for face classification and 100% for dynamic vehicle flow recognition. The in-sensor RC system takes advantage of near-zero energy consumption in the reservoir, resulting in decades-time lower training costs than a conventional neural network. This work paves the way for ultralow-power machine vision using photonic devices.

Electric-Field-Induced Room-Temperature Antiferroelectric-Ferroelectric Phase Transition in van der Waals Layered GeSe

Searching van der Waals ferroic materials that can work under ambient conditions is of critical importance for developing ferroic devices at the two-dimensional limit. Here we report the experimental discovery of electric-field-induced reversible antiferroelectric (AFE) to ferroelectric (FE) transition at room temperature in van der Waals layered α-GeSe, employing Raman spectroscopy, transmission electron microscopy, second-harmonic generation, and piezoelectric force microscopy consolidated by first-principles calculations. An orientation-dependent AFE-FE transition provides strong evidence that the in-plane (IP) polarization vector aligns along the armchair rather than zigzag direction in α-GeSe. In addition, temperature-dependent Raman spectra showed that the IP polarization could sustain up to higher than 700 K. Our findings suggest that α-GeSe, which is also a potential ferrovalley material, could be a robust building block for creating artificial 2D multiferroics at room temperature.

Novel 2D CaCl crystals with metallicity, room-temperature ferromagnetism, heterojunction, piezoelectricity-like property and monovalent calcium ions

Under ambient conditions, the only known valence state of calcium ions is +2, and the corresponding crystals with calcium ions are insulating and nonferromagnetic. Here, using cryo-electron microscopy, we report direct observation of two-dimensional (2D) CaCl crystals on reduced graphene oxide (rGO) membranes, in which the calcium ions are only monovalent (i.e. +1). Remarkably, metallic rather than insulating properties are displayed by those CaCl crystals. More interestingly, room-temperature ferromagnetism, graphene-CaCl heterojunction, coexistence of piezoelectricity-like property and metallicity, as well as the distinct hydrogen storage and release capability of the CaCl crystals in rGO membranes are experimentally demonstrated. We note that such CaCl crystals are obtained by simply incubating rGO membranes in salt solutions below the saturated concentration, under ambient conditions. Theoretical studies suggest that the formation of those abnormal crystals is attributed to the strong cation-π interactions of the Ca cations with the aromatic rings in the graphene surfaces. The findings highlight the realistic potential applications of such abnormal CaCl material with unusual electronic properties in designing novel transistors and magnetic devices, hydrogen storage, catalyzers, high-performance conducting electrodes and sensors, with a size down to atomic scale.

A proof-of-concept study of an automated solution for clinical metagenomic next-generation sequencing

AIMS

Metagenomic next-generation sequencing (mNGS) has been utilized for diagnosing infectious diseases. It is a culture-free and hypothesis-free nucleic acid test for diagnosing all pathogens with known genomic sequences, including bacteria, fungi, viruses and parasites. While this technique greatly expands the clinical capacity of pathogen detection, it is a second-line choice due to lengthy procedures and microbial contaminations introduced from wet-lab processes. As a result, we aimed to reduce the hands-on time and exogenous contaminations in mNGS.

METHODS AND RESULTS

We developed a device (NGSmaster) that automates the wet-lab workflow, including nucleic acid extraction, PCR-free library preparation and purification. It shortens the sample-to-results time to 16 and 18·5 h for DNA and RNA sequencing respectively. We used it to test cultured bacteria for validation of the workflow and bioinformatic pipeline. We also compared PCR-free with PCR-based library prep and discovered no differences in microbial reads. Moreover we analysed results by automation and manual testing and found that automation can significantly reduce microbial contaminations. Finally, we tested artificial and clinical samples and showed mNGS results were concordant with traditional culture.

CONCLUSION

NGSmaster can fulfil the microbiological diagnostic needs in a variety of sample types.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study opens up an opportunity of performing in-house mNGS to reduce turnaround time and workload, instead of transferring potentially contagious specimen to a third-party laboratory.

MGa2B2O7:Bi3+,Al3+ (M = Sr, Ba) blue phosphors with a quantum yield of 99% and negative thermal quenching

The quantum yields of non-rare-earth blue phosphors SrGa2B2O7:Bi3+,Al3+ and BaGa2B2O7:Bi3+,Al3+ reach record high values of 96% and 99%, respectively. The SrGa2B2O7:Bi3+,Al3+ phosphor exhibits negative thermal quenching.

The effect of in-hospital high-dose vs. low-dose intensive statin in patients with non-ST segment elevation acute coronary syndrome

Background

Statins remain a standard treatment for acute coronary syndrome (ACS) patients. We aimed to determine the association between different dosages of in-hospital statins and the prognoses among patients receiving percutaneous coronary intervention (PCI).

Methods

NSTE-ACS patients were retrospectively enrolled from January 2010 to December 2014 from five centres in China. Patients receiving either atorvastatin or rosuvastatin during their hospitalizations were included. All the patients were categorized into high-dose statin group (40mg atorvastatin or 20mg rosuvastatin) or low-dose statin group (20mg atorvastatin or 10mg rosuvastatin). In-hospital events and long-term all-cause death was recorded.

Results

Of the 7,008 patients included in the study, 5,248 received low-dose intensive statin (mean age: 64.28±10.39; female: 25.2%), and 1,760 received high-dose intensive statin (mean age: 63.68±10.59; female: 23.1%). There was no significant difference in in-hospital all-cause death between the two groups (adjusted OR, 1.27; P=0.665). All-cause death was similar between the two groups during the long-term follow-up period (30-day: adjusted HR, 1.28; P=0.571; 3-year: adjusted HR, 0.83; P=0.082). However, there was a robust association between the high-dose statin and the reduction in in-hospital dialysis (adjusted OR, 0.11; P=0.030).

Conclusions

The in-hospital high-dose intensive statin is not associated with lower risks of in-hospital or follow-up all-cause death in NSTE-ACS patients undergoing PCI. Considering the robust beneficial effect of in-hospital dialysis, an individualized high-dose intensive statin can be rational in specified populations.

Univariate and multivariate analyses

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Science and Technology Planning Project of Guangzhou City athe China Youth Research Funding

Coronavirus disease 2019 among pregnant Chinese women: case series data on the safety of vaginal birth and breastfeeding

OBJECTIVE

To assess whether vaginal secretions and breast milk of women with coronavirus disease 2019 (COVID-19) contain severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

DESIGN

Single centre cohort study.

SETTING

Renmin Hospital of Wuhan University, Wuhan, Hubei province, China.

POPULATION

We studied 13 SARS-CoV-2-infected pregnant women diagnosed between 31 January and 9 March 2020.

METHODS

We collected clinical data, vaginal secretions, stool specimens and breast milk from SARS-CoV-2-infected women during different stages of pregnancy and collected neonatal throat and anal swabs.

MAIN OUTCOMES AND MEASURES

We assessed viral presence in different biosamples.

RESULTS

Of the 13 women with COVID-19, five were in their first trimester, three in their second trimester and five in their third trimester. Of the five women in their third trimester who gave birth, all delivered live newborns. Among these five deliveries, the primary adverse perinatal outcomes included premature delivery (n = 2) and neonatal pneumonia (n = 2). One of nine stool samples was positive; all 13 vaginal secretion samples, and five throat swabs and four anal swabs collected from neonates, were negative for the novel coronavirus. However, one of three samples of breast milk was positive by viral nucleic acid testing.

CONCLUSIONS

In this case series of 13 pregnant women with COVID-19, we observed negative viral test results in vaginal secretion specimens, suggesting that a vaginal delivery may be a safe delivery option. However, additional research is urgently needed to examine breast milk and the potential risk for viral contamination.

TWEETABLE ABSTRACT

New evidence for the safety of vaginal delivery and breastfeeding in pregnant women infected with SARS-CoV-2, positive viral result in a breast-milk sample.

Enhanced and Balanced Charge Transport Boosting Ternary Solar Cells Over 17% Efficiency

Ternary architecture is one of the most effective strategies to boost the power conversion efficiency (PCE) of organic solar cells (OSCs). Here, an OSC with a ternary architecture featuring a highly crystalline molecular donor DRTB-T-C4 as a third component to the host binary system consisting of a polymer donor PM6 and a nonfullerene acceptor Y6 is reported. The third component is used to achieve enhanced and balanced charge transport, contributing to an improved fill factor (FF) of 0.813 and yielding an impressive PCE of 17.13%. The heterojunctions are designed using so-called pinning energies to promote exciton separation and reduce recombination loss. In addition, the preferential location of DRTB-T-C4 at the interface between PM6 and Y6 plays an important role in optimizing the morphology of the active layer.

Ferroelectric-like Behavior Originating from Oxygen Vacancy Dipoles in Amorphous Film for Non-volatile Memory

Traditional ferroelectric devices suffer a lack of scalability. Doped HfO₂ thin film is promising to solve the scaling problem but challenged by high leakage current and uniformity concern by the polycrystalline nature. Stable ferroelectric-like behavior is firstly demonstrated in a 3.6-nm-thick amorphous Al₂O₃ film. The amorphous Al₂O₃ devices are highly scalable, which enable multi-gate non-volatile field-effect transistor (NVFET) with nanometer-scale fin pitch. It also possesses the advantages of low process temperature, high frequency (~GHz), wide memory window, and long endurance, suggesting great potential in VLSI systems. The switchable polarization (P) induced by the voltage-modulated oxygen vacancy dipoles is proposed.

ZrO2 Ferroelectric Field-Effect Transistors Enabled by the Switchable Oxygen Vacancy Dipoles

This paper investigates the impacts of post-rapid thermal anneal (RTA) and thickness of ZrO₂ on the polarization P and electrical characteristics of TaN/ZrO₂/Ge capacitors and FeFETs, respectively. After the RTA ranging from 350 to 500 °C, TaN/ZrO₂/Ge capacitors with 2.5 and 4 nm-thick amorphous ZrO₂ film exhibit the stable P. It is proposed that the ferroelectric behavior originates from the migration of the voltage-driven dipoles formed by the oxygen vacancies and negative charges. FeFETs with 2.5 nm, 4 nm, and 9 nm ZrO₂ demonstrate the decent memory window (MW) with 100 ns program/erase pulses. A 4-nm-thick ZrO₂ FeFET has significantly improved fatigue and retention characteristics compared to devices with 2.5 nm and 9 nm ZrO₂. The retention performance of the ZrO₂ FeFET can be improved with the increase of the RTA temperature. An MW of ~ 0.46 V is extrapolated to be maintained over 10 years for the device with 4 nm ZrO₂.

Research progress on solutions to the sneak path issue in memristor crossbar arrays

Since the emergence of memristors (or memristive devices), how to integrate them into arrays has been widely investigated. After years of research, memristor crossbar arrays have been proposed and realized with potential applications in nonvolatile memory, logic and neuromorphic computing systems. Despite the promising prospects of memristor crossbar arrays, one of the main obstacles for their development is the so-called sneak-path current causing cross-talk interference between adjacent memory cells and thus may result in misinterpretation which greatly influences the operation of memristor crossbar arrays. Solving the sneak-path current issue, the power consumption of the array will immensely decrease, and the reliability and stability will simultaneously increase. In order to suppress the sneak-path current, various solutions have been provided. So far, some reviews have considered some of these solutions and established a sophisticated classification, including 1D1M, 1T1M, 1S1M (D: diode, M: memristor, T: transistor, S: selector), self-selective and self-rectifying memristors. Recently, a mass of studies have been additionally reported. This review thus attempts to provide a survey on these new findings, by highlighting the latest research progress realized for relieving the sneak-path issue. Here, we first present the concept of the sneak-path current issue and solutions proposed to solve it. Consequently, we select some typical and promising devices, and present their structures and properties in detail. Then, the latest research activities focusing on single-device structures are introduced taking into account the mechanisms underlying these devices. Finally, we summarize the properties and perspectives of these solutions.

Characterization and Application of PVDF and Its Copolymer Films Prepared by Spin-Coating and Langmuir-Blodgett Method

Poly(vinylidene fluoride) (PVDF) and its copolymers are key polymers, displaying properties such as flexibility and electroactive responses, including piezoelectricity, pyroelectricity, and ferroelectricity. In the past several years, they have been applied in numerous applications, such as memory, transducers, actuators, and energy harvesting and have shown thriving prospects in the ongoing research and commercialization process. The crystalline polymorphs of PVDF can present nonpolar α, ε phase and polar β, γ, and δ phases with different processing methods. The copolymers, such as poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)), can crystallize directly into a phase analogous to the β phase of PVDF. Since the β phase shows the highest dipole moment among polar phases, many reproducible and efficient methods producing β-phase PVDF and its copolymer have been proposed. In this review, PVDF and its copolymer films prepared by spin-coating and Langmuir-Blodgett (LB) method are introduced, and relevant characterization techniques are highlighted. Finally, the development of memory, artificial synapses, and medical applications based on PVDF and its copolymers is elaborated.

Timing Dissociative Ionization of H_{2} Using a Polarization-Skewed Femtosecond Laser Pulse

We experimentally observe the bond stretching time of one-photon and net-two-photon dissociation pathways of singly ionized H_{2} molecules driven by a polarization-skewed femtosecond laser pulse. By measuring the angular distributions of the ejected photoelectron and nuclear fragments in coincidence, the cycle-changing polarization of the laser field enables us to clock the photon-ionization starting time and photon-dissociation stopping time, analogous to a stopwatch. After the single ionization of H_{2}, our results show that the produced H_{2}^{+} takes almost the same time in the one-photon and net-two-photon dissociation pathways to stretch to the internuclear distance of the one-photon coupled dipole-transition between the ground and excited electronic states. The spatiotemporal mapping character of the polarization-skewed laser field provides us a straightforward route to clock the ultrafast dynamics of molecules with sub-optical-cycle time resolution.

[Clinical characteristics and prognosis of high-risk neuroblastoma with bone marrow metastasis in children]

Objective: To analyze the clinical characteristics of newly treated high-risk group neuroblastoma (NB) patients with bone marrow metastasis and to explore the prognostic factors. Methods: The clinical features (sex, age, stage, risk group, pathological type, metastatic site, etc.) of 203 newly treated high-risk NB patients with bone marrow metastasis admitted to Hematology Oncology Center, Beijing Children's Hospital from January 2007 to December 2016 were analyzed retrospectively. There were 118 males (58.1%) and 85 females (41.9%). Kaplan-Meier method was used for survival analysis and Cox regression was used to analyze the prognostic factors. Results: The age at onset of the 203 patients was 41 months (9-147 months). The metastatic sites at diagnosis were as follows: bone in 195 cases (96.1%), distant lymph nodes in 104 cases (51.2%), skull and endomeninx in 61 cases (30.0%), orbit in 30 cases (14.8%), pleura in 16 cases (7.9%), liver in 13 cases(6.4%), canalis spinalis in 13 cases (6.4%), other sites in 11 cases (5.4%) and skin and soft tissue in 10 cases (4.9%). In all, 194 cases were enrolled for prognostic analysis. The follow-up time was 36 months (1 day-138 months) , and the 5-years event free survival (EFS) and overall survival (OS) were 36.1% and 39.7%, respectively. A total of 118 patients (60.8%) had events (first relapse or death) with the time to event occurrence was 15 months (1 day-72 months), whereas 112 patients (57.7%) died with the event occurrence to death time was 3 months (1 day-21 months). There was no significant difference in 5-years OS between radiotherapy group and non-radiotherapy group (42.3% vs. 38.3%, χ(2)=3.671, P=0.055). The 5-years OS in transplantation group was significantly better than the non-transplantation group (44.3% vs. 35.5%, χ(2)=8.878, P=0.003), and the radiotherapy combined transplantation group also had a better 5-years OS rate than the non-radiotherapy combined transplantation group (45.8% vs. 37.3%, χ(2)=5.945, P=0.015). Univariate survival analysis showed lactate dehydrogenase ≥ 1 500 U/L, the amplification of MYCN, the metastatic sites of orbit, canalis spinalis and pleura were associated with poor prognosis of newly diagnosed high-risk NB patients (χ(2)=21.064, 13.601, 3.998, 6.183, 15.307, all P<0.05). The amplification of MYCN and the metastatic sites of pleura were risk factors for prognosis of newly diagnosed high-risk NB patients by Cox regression models (HR=1.896,1.100, 95%CI: 1.113-3.231, 1.020-1.187, both P<0.05). Conclusions: The prognosis is unfavorable in high-risk group NB patients with BM metastasis. Radiotherapy combined with transplantation can further improve the prognosis of these patients. The amplification of MYCN and the metastatic sites of pleura were the poor prognostic factors for high-risk NB patients with bone marrow metastasis.

[Clinical and prognostic analysis of single-center multidisciplinary treatment for rhabdomyosarcoma in children]

Objective: To summarize the clinical characteristics, treatment response and prognostic factors of rhabdomyosarcoma (RMS) in children. Methods: The clinical characteristics such as age at diagnosis, primary tumor site, tumor size, pathological type, clinical stage, and risk grouping of 213 RMS patients (140 males and 73 females) treated in Hematology Oncology Center of Beijing Children's Hospital, Capital Medical University, from May 2006 to June 2018 were analyzed retrospectively. The clinical characteristics, overall survival (OS), event free survival (EFS) and prognostic factors of children treated with the Beijing Children's Hospital-Rhabdomyosarcoma (BCH-RMS) regimen were analyzed. Survival data were analyzed by Kaplan-Meier survival analysis, and single factor analysis was performed by Log-Rank test. Results: The diagnostic age of 213 cases was 48.0 months (ranged 3.0-187.5 months), of which 136 cases (63.8%) were younger than 10 years old. The head and neck region was the most common primary site of tumor (30%, 64 cases), followed by the genitourinary tract (26.8%, 57 cases). Among pathological subtypes, embryonal RMS accounted for 71.4% (152 cases), while alveolar RMS and anaplastic RMS accounted for only 26.8% (57 cases) and 1.9% (4 cases), respectively. According to the Intergroup Rhabdomyosarcoma Study Group (IRS), IRS-Ⅲ and Ⅳ accounted for 85.0% (181 cases) of all RMS patients. In all patients, 9.4% (20 cases) patients were divided in to low-risk group, 52.1% (111 cases) patients in to intermediate -risk group, 25.8% (55 cases) patients in to high-risk group, and 12.7% (27 cases) patients in to the central nervous system invasion group, respectively. All patients with RMS received chemotherapy. The cycles of chemotherapy were 13.5 (ranged 5.0-18.0) for patients without event occurrence, while 14.2 (ranged 3.0-30.0) for patients with event occurrence. Among the 213 patients, 200 patients had surgical operation, of whom 103 patients underwent surgery before chemotherapy and 97 patients at the end of chemotherapy, 21 patients had secondary surgical resection. Radiotherapy was performed in 114 patients. The follow-up time was 23.0 months (ranged 0.5-151.0 months) . There were 98 patients with relapsed or progressed disease and 67 patients with death. The median time to progression was 10 months, of which 67 (68.4%) relapse occurred within 1 year and no recurrence occurred after follow-up for more than 5 years. The 3-year EFS and 5-year EFS were (52±4) % and (48±4) %, while the 3-year OS and 5-year OS were (65±4) % and (64±4) % by survival analysis. The 5-year OS of the low-risk, intermediate-risk, the high-risk were 100%, (74±5) %, (48±8) %, and the 2-year OS of the central nervous system invasion group was (36±11) % (χ(2)=33.52, P<0.01). The 5-year EFS of the low-risk, intermediate-risk, the high-risk were (93±6) %, (51±5) %, (36±7) % and the 2-year EFS of the central nervous system invasion group was (31±10) % (χ(2)=24.73, P<0.01) . Survival factor analysis suggested that the OS of children was correlated with age(χ(2)=4.16, P=0.038), tumor TNM stage (χ(2)=22.02, P=0.001), IRS group (χ(2)=4.49, P<0.01) and the risk group (χ(2)=33.52, P<0.01). Conclusions: This study showed that the median age of newly diagnosed RMS patients was 4 years. The head and neck and the genitourinary tract were the most common primary origin of RMS. The OS was low in single-center RMS children. The median time to recurrence was 10 months, and recurrence was rare 3 years later.

Extremely Low-Cost and Green Cellulose Passivating Perovskites for Stable and High-Performance Solar Cells

The fast evolution of metal halide perovskite solar cells has opened a new chapter in the field of renewable energy. High-quality perovskite films as the active layers are essential for both high efficiency and long-term stability. Here, the perovskite films with enlarged crystal grain size and decreased defect density are fabricated by introducing the extremely low-cost and green polymer, ethyl cellulose (EC), into the perovskite layer. The addition of EC triggers hydrogen bonding interactions between EC and the perovskite, passivating the charge defect traps at the grain boundaries. The long chain of EC further acts as a scaffold for the perovskite structure, eliminating the annealing-induced lattice strain during the film fabrication process. The resulting devices with the EC additive exhibit a remarkably enhanced average power conversion efficiency from 17.11 to 19.27% and an improvement of all device parameters. The hysteresis index is found to decrease by three times from 0.081 to 0.027, which is attributed to suppressed ion migration and surface charge trapping. In addition, the defect passivation by EC significantly improves the environmental stability of the perovskite films, yielding devices that retain 80% of their initial efficiency after 30 days in ambient air at 45% relative humidity, whereas the pristine devices without EC fully degrade. This work provides a low-cost and green avenue for passivating defects that improves both the efficiency and operational stability of perovskite solar cells.

Oxygen- and Water-Induced Energetics Degradation in Organometal Halide Perovskites

Organometal halide perovskites are under rapid development, and significant focus has been placed on their stability that currently presents a major obstacle for practical application. Energetics plays a vital role in charge injection/extraction and transport properties in devices. Here, we in situ investigate oxygen- and water-induced energetics degradation in organometal halide perovskite films. Oxygen gas induces an upward shift of the vacuum level of the perovskite films because of the formation of an oxygen-induced surface dipole, water vapor causes a significant vacuum-level downshift, and the valence band binding energy referenced to the Fermi level simultaneously increases so as to keep the ionization potential of the perovskite films unchanged. Moreover, the chemical compositions, crystalline structures, surface morphologies, and dynamical properties also are monitored and analyzed in detail. These results are indispensable to understand the degradation mechanisms and to perform the optimizations of stable materials and devices in the future.

Family History of Melanoma and Lifetime Patterns of Daytime Hours Spent Outdoors in Melanoma-prone Families

Longer daytime hours spent outdoors reflect higher ultraviolet radiation exposure, which is a modifiable risk factor of melanoma. Among individuals of melanoma-prone families, we sought to describe lifetime patterns for hours spent outdoors, and to investigate whether having an affected family member with melanoma from an older generation was associated with patterning. Methods: Information on hours spent outdoors on weekdays, weekends, and holidays beginning at age 10 was obtained from individuals from melanoma-prone families. We determined time-weighted average hours outdoors for warmer months, colder months, and the entire year. K-means for longitudinal data was used to identify lifetime patterns. We created a variable to indicate whether there was an existing melanoma in a prior generation of an individual's family. Multinomial logistic regression models were used to examine the association between family history of melanoma and lifetime patterns of daytime hours spent outdoors, adjusting for covariates. Results: We analyzed 2540 individuals from 669 families ascertained across 15 countries, and four lifetime patterns were identified. Three patterns began with moderate hours that (B) decreased slowly (n = 1014); (C) decreased sharply until age 20 and then remained low (n = 572); or (D) increased at age 20 and remained high (n = 173). One pattern, (A) began with few hours that decreased at age 20 then remained very low (n = 781). Compared to individuals with the high (D) pattern, individuals with an existing melanoma in a prior family generation were more likely to have the low (A) pattern (OR = 1.92, 95% CI: 1.34–2.76), the moderate and slowly decreasing (B) pattern (OR = 1.72, 95% CI: 1.15–2.57), or the sharply decreasing (C) pattern (OR = 2.01, 95% CI: 1.40–2.87). Similar associations were observed separately in warmer and colder months. Examining lifetime patterns of hours spent outdoors during holidays, we noticed a stronger relationship with family history of melanoma in warmer months than in colder months. Conclusions: As expected, the diagnosis of a melanoma in a prior generation may impact family members' awareness of UVR exposure leading to reduced daytime hours spent outdoors.

The Effect of Oxygen Uptake on Charge Injection Barriers in Conjugated Polymer Films

The energy offset between the electrode Fermi level and organic semiconductor transport levels is a key parameter controlling the charge injection barrier and hence efficiency of organic electronic devices. Here, we systematically explore the effect of in situ oxygen exposure on energetics in n-type conjugated polymer P(NDI2OD-T2) films. The analysis reveals that an interfacial potential step is introduced for a series of P(NDI2OD-T2) electrode contacts, causing a nearly constant downshift of the vacuum level, while the ionization energies versus vacuum level remain constant. These findings are attributed to the establishment of a so-called double-dipole step via motion of charged molecules and will modify the charge injection barriers at electrode contact. We further demonstrate that the same behavior occurs when oxygen interacts with p-type polymer TQ1 films, indicating it is possible to be a universal effect for organic semiconductors.

Energy Level Alignment of N-Doping Fullerenes and Fullerene Derivatives Using Air-Stable Dopant

Doping has been proved to be one of the powerful technologies to achieve significant improvement in the performance of organic electronic devices. Herein, we systematically map out the interface properties of solution-processed air-stable n-type (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl) doping fullerenes and fullerene derivatives and establish a universal energy level alignment scheme for this class of n-doped system. At low doping levels at which the charge-transfer doping induces mainly bound charges, the energy level alignment of the n-doping organic semiconductor can be described by combining integer charger transfer-induced shifts with a so-called double-dipole step. At high doping levels, significant densities of free charges are generated and the charge flows between the organic film and the conducting electrodes equilibrating the Fermi level in a classic "depletion layer" scheme. Moreover, we demonstrate that the model holds for both n- and p-doping of π-backbone molecules and polymers. With the results, we provide wide guidance for identifying the application of the current organic n-type doping technology in organic electronics.

Interfacial memristors in Al–LaNiO3heterostructures

Self-assembled interfacial memristive systems in Al–LaNiO₃heterostructures.

Extraction of structural and chemical information from high angle annular dark-field image by an improved peaks finding method

With the development of spherical aberration (Cs) corrected scanning transmission electron microscopy (STEM), high angle annular dark filed (HAADF) imaging technique has been widely applied in the microstructure characterization of various advanced materials with atomic resolution. However, current qualitative interpretation of the HAADF image is not enough to extract all the useful information. Here a modified peaks finding method was proposed to quantify the HAADF-STEM image to extract structural and chemical information. Firstly, an automatic segmentation technique including numerical filters and watershed algorithm was used to define the sub-areas for each atomic column. Then a 2D Gaussian fitting was carried out to determine the atomic column positions precisely, which provides the geometric information at the unit-cell scale. Furthermore, a self-adaptive integration based on the column position and the covariance of statistical Gaussian distribution were performed. The integrated intensities show very high sensitivity on the mean atomic number with improved signal-to-noise (S/N) ratio. Consequently, the polarization map and strain distributions were rebuilt from a HAADF-STEM image of the rhombohedral and tetragonal BiFeO3 interface and a MnO2 monolayer in LaAlO3 /SrMnO3 /SrTiO3 heterostructure was discerned from its neighbor TiO2 layers. Microsc. Res. Tech. 79:820-826, 2016. © 2016 Wiley Periodicals, Inc.

A meta-analysis of reflectance confocal microscopy for the diagnosis of malignant skin tumours

Early diagnosis is extremely important for treatment and prognosis of skin cancer. Reflectance confocal microscopy (RCM) is a recently developed technique used to diagnose skin cancer. This meta-analysis was carried out to assess the accuracy of RCM for the diagnosis of malignant skin tumours. We conducted a systematic literature search of EMBASE, PubMed, the Cochrane Library and Web of Science database for relevant articles in English published up to 24 December 2015. The quality of the included studies was assessed using the QUADAS-2 tool. Statistical analyses were conducted using the software Meta-Disc version 1.4 and STATA version 12.0. A total of 21 studies involving 3108 patients with a total of 3602 lesions were included in the per-lesion analysis. The corresponding pooled results for sensitivity and specificity were 93.6% (95% CI: 0.92-0.95) and 82.7% (95% CI: 0.81-0.84) respectively. Positive likelihood ratio and negative likelihood ratio were 5.84 (95% CI: 4.27-7.98) and 0.08 (95% CI: 0.07-0.10) respectively. Subgroup analysis showed that RCM had a sensitivity of 92.7% (95% CI: 0.90-0.95) and a specificity of 78.3% (95% CI: 0.76-0.81) for detecting melanoma. The pooled sensitivity and specificity of RCM for detecting basal cell carcinoma were 91.7% (95% CI: 0.87-0.95) and 91.3% (95% CI: 0.94-0.96) respectively. RCM is a valid method of identifying malignant skin tumours accurately.

Low nanomolar concentrations of Cucurbitacin-I induces G2/M phase arrest and apoptosis by perturbing redox homeostasis in gastric cancer cells in vitro and in vivo

Cucurbitacin-I (Cu-I, also known as Elatericin B or JSI-124) is developed to inhibit constitutive and abnormal activation of STAT3 in many cancers, demonstrating a potent anticancer activity by targeting disruption of STAT3 function. Here, we for the first time systematically studied the underlying molecular mechanisms of Cu-I-induced gastric cancer cell death both in vitro and in vivo. In our study, we show that Cu-I markedly inhibits gastric cancer cell growth by inducing G2/M phase cell cycle arrest and apoptosis at low nanomolar concentrations via a STAT3-independent mechanism. Notably, Cu-I significantly decreases intracellular GSH/GSSG ratio by inhibiting NRF2 pathway to break cellular redox homeostasis, and subsequently induces the expression of GADD45α in a p53-independent manner, and activates JNK/p38 MAPK signaling. Interestingly, Cu-I-induced GADD45α and JNK/p38 MAPK signaling form a positive feedback loop and can be reciprocally regulated by each other. Therefore, the present study provides new insights into the mechanisms of antitumor effects of Cu-I, supporting Cu-I as an attractive therapeutic drug in gastric cancer by modulating the redox balance.

Association of Resting Heart Rate with Infrarenal Aortic Diameter: A Cross Sectional Study in Chinese Hypertensive Adults

OBJECTIVE

Elevated resting heart rate (RHR) has been shown to be a risk marker for cardiovascular disease. Results from studies on the effects of RHR in large arteries are limited to the functional changes of those arteries, while the association between RHR and aortic diameter remains largely understudied.

METHODS

This was a cross sectional study of hypertensive Chinese adults from rural areas. The maximum infrarenal aortic diameter (maxIAD) from renal arteries to the iliac bifurcation was obtained by ultrasound. MaxIADs in different RHR groups were compared in males and females separately because of the significant differences between sexes. Multiple regression analysis was used to determinate the correlation between RHR and maxIAD. Further interactions between three factors (BMI, smoking, and anti-hypertensive regimens) and RHR for maxIAD were examined using subgroup analysis.

RESULTS

19,200 subjects were enrolled in the study, with an average age of 64.8±7.4 years and 61.6% females. Only 22 cases (0.11%) were detected with AAA, with males (n = 17) presenting a higher AAA incidence than females (n = 5). In subjects ≥65 years, there were 18 (0.19%) AAA, and 15 (83.3%) had a history of smoking. In the total subjects, the mean maxIAD ranged from 15.7±2.1 mm to 15.2±2.2 mm as RHR changed from the lowest quartile to the highest (≥84 bpm) in males, with a similar tendency observed in females. The correlation coefficient of RHR on maxIAD was -0.17 in males and -0.12 in females. Further subgroup analysis revealed that smoking exaggerated the correlation between RHR and maxIAD, but only in females.

CONCLUSIONS

A low AAA incidence was observed in this hypertensive Chinese population. There was a negative association between RHR and maxIAD, potentially exaggerated by smoking, especially in females.

Photothrombosis combined with thrombin injection establishes a rat model of cerebral venous sinus thrombosis

OBJECTIVE

Cerebral venous sinus thrombosis (CVST) is a rare but life-threatening disease and an animal model for in-depth study of CVST is needed. This study aimed to develop a rat model suitable for studying clinically relevant aspects of CVST and investigating its dynamic pathophysiological changes during a 7-day period.

METHOD

A photothrombosis method was used to create a rat sinus-vein thrombosis model. A spot size-adjustable Diode Pumped Solid State laser (DPSS) combined with thrombin injection occluded the rostral and caudal superior sagittal sinus (SSS). The model was used to evaluate pathophysiological changes at different time points over 7 days. Evans Blue dye injection was used to detect alterations in blood-brain barrier (BBB) permeability. Brain water content was also measured. Moreover, we examined changes in brain infarct volume, neurological function, as well as histology after induction of CVST.

RESULT

CVST in rats significantly altered BBB permeability, consistent with the development of brain edema. It was accompanied by an increase in brain infarct volume and deficits in neurological function that began on day 1, peaked on day 2, and typically improved by day 7 due to the neuroprotective effects of angiogenesis and gliocyte proliferation.

CONCLUSION

In this study, we describe a rat model that produces clinically relevant pathophysiology and pathology that will facilitate evaluation of therapeutic regimens for CVST. Furthermore, our results indicate a period of optimal clinical intervention for patients with CVST, which may reduce the probability of dependency and death.